THE GUIDE TO HOT STAMPING

AND FOIL SELECTION

A Note on the downloadable PDF version of the Milford Astor Guide to Hot Stamping and Foil Selection.

This version of the foil catalogue does not include any foil or colour swatches as colours and finishes can not be replicated on a computer screen. If you are interested in getting samples of the foils mentioned in this catalogue please contact your Milford Astor Sales Representative or email us: sales@astor.com.au.

THE INTERNATIONAL CERTIFICATION NETWORK

MEMBER

CERTIFICATE OF REGISTRATIONMilford Astor Printing Systems

2 Rothschild Avenue ROSEBERY NSW 2018 AUSTRALIA

Milford Astor Pty Ltd

21 Temple Drive THOMASTOWN VIC 3074 AUSTRALIA

ABN 70 004 321 322

complies with the requirements of

AS/NZS ISO 9001:2000Quality management systems Requirements

for the following capability

Registered by:

Originally certified to AS/NZS ISO 9002 on 20 August 1993

Milford Astor Foilmakers

Certificate No.: QEC2098Issue Date: 11 November 2005

Certified Date: 09 February 2004Expiry Date: 24 November 2006

Alex EzrakhovichGeneral Manager Certificationfor and on behalf ofSAI Global Limited Authorised Local Signatory, SAI Global

Assurance Services

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The registration covers the Quality Management System for the manufacture, procurement, warehousing, slitting and distribution of pigmented and metallised hot stampig foil; procurement, warehousing, slitting and distribution of thermal transfer ribbon, the purchase and distribution of machines for marking, coding and product embellishment and associated equipment and supplies; the servicing and technical support of supplied machines; the production of artwork, manufacture and supply of printing elements.

SAI Global Certification Services Pty Ltd (ACN 108 716 669) 286 Sussex Street Sydney NSW 2000 Australia with SAI Global Limited(”SAI Global”) and subject to the SAI Global Terms and Conditions for Certification. While all due care and skill was exercised in carrying out

this assessment, SAI Global accepts responsibility only for proven negligence. This certificate remains the property os SAI Global and must bereturned to SAI Global upon request.

Assurance Services ACCREDITED

www.jas-anz.com.au/register

M

EMBER OF MULTILATERAL

R

ECOGNITION ARRANGEMENT

standardsassuranceinnovation

Milford Astor Foilmakers

MELBOURNE

21 Temple Drive

Thomastown VIC 3074

Ph: (03) 9465 0166

Fax: (03) 9464 1024

SYDNEY

2 Rothschild Avenue

Rosebery NSW 2018

Ph: (02) 9663 3911

Fax: (02) 9662 1020

ADELAIDE

1A West Thebarton Road

Thebarton SA 5031

Ph: (08) 8234 5466

Fax: (08) 8352 3712

Milford Astor

www.astor.com.aue-mail: sales@astor.com.au

Contents

Basic Hot Stamping Information

Hot Stamping History, Manufacture & Stamping Equipment

Foil & Shade Selection Guides

Metallic Foils for Graphics, Plastics, Leather & Fabrics

Matt Pigment Foils

Gloss & Semi-Gloss Foils for Plastics

Pearl Foils

Metallic Foils for Rotary & Cylinder Presses

Specialty Foils

Quick Application Reference

Hot Stamping Operation

Bottle Stamping & Roll-on Stamping

Hot Stamping Substrates

Stamping Dies

Make-Ready Materials & General Supplies

Tips to Save Pains & Strains

Weights & Measurements of Master Rolls

Foil Requirements Calculator

Table of Cuts

Common Problems and Solutions

Glossary of Hot Stamping Terms

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Milford Astor

Basic Hot Stamping Information

Selection of Foils

This catalogue has been published to illustrate and describe our hot stamping foils available for

marking and decorating a wide variety of materials. It includes essential product specifications

to guide and assist in the selection and application of foils.

Milford Astor offers the widest selection of grades, colours and finishes, and maintain the industry's

largest stock in strategically located warehouses to ensure prompt delivery. Recommendations for

usage are to help in selecting the correct foil to meet a particular application.

Please request samples for testing and evaluation in your own plant. When requesting

samples, please specify or submit materials to be stamped.

Our foil testing facilities together with technical sales people are at your service for consultation

and assistance.

The following pages are designed to assist in the selection of foils for particular applications.

However, the information given is intended purely as a guide.

In many cases more than one grade of foil has been recommended for a particular application.

This is because of the wide range of hot stamping machines in use and the variations

encountered in substrates and print requirements. For these reasons it is essential that

customers carry out their own tests to ascertain the most suitable grade for their application.

Metallic Shades

Shade references should be checked against the colour cards before ordering. However, owing

to variations in formulas from one grade to another, each has its own distinctive characteristics,

giving a slightly different appearance between shades with the same reference numbers.

Pigment Shades

The colour charts show shades obtained when a solid area is stamped onto a white gloss card.

NOTE: Some pigments such as red and maroon can smudge if rubbed. It is the responsibility

of the customer to test for abrasion and smudge resistance.

Shades may appear slightly darker if stamped:

a) at too high a temperature

b) with too much pressure

c) with too much dwell

d) in fine detail work

e) on a very dark or contrasting background

They may appear slightly lighter if stamped:

a) at too low a temperature

b) with too little pressure

c) with a rubber die

d) with insufficient dwell

e) on a similar coloured background

f) onto clear plastic

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Milford Astor

If required, we can supply foils that are non-toxic according to standards laid down by health

authorities. Our technical staff will assist you in making your choice.

Toxicity

Metal Corrosion

When metallised foils are stamped onto ink, plastic surfaces, or materials that contain certain

chemicals, there is a possibility that the metallic layer may be attacked. This possibility is even

more likely if the substrate is moist at the time of stamping, e.g., from a gluing operation, or if

stored after blocking in an atmosphere of high humidity.

It is essential that before any stamping programme is carried out on such substrates, test

stampings are made and prints subjected to high humidity for a period of two or three days.

Migration (Plasticisers)

When foils are stamped onto soft flexible plastics, such as PVC, there is a possibility that the

plasticisers used in such substrates will migrate into the foiled area. The surface of this area

may become 'tacky' or smudge and in the case of coloured metallic and gold foils the colour will

gradually fade. This may occur after blocking where work is stacked. In our range there are

foils designed to reduce this possibility. However, because circumstances at the time of

blocking are beyond our control, we cannot assume any liability and would stress that tests for

plasticiser migration be carried out before any blocking is attempted on such substrates, and

test prints be subjected to heat and pressure for a period of two or three days.

Oxidation

Some metallic foils and imitation bronze powder foils when blocked onto natural leathers may

eventually be affected by oxidation. They can also corrode when in contact with any acidity on

the substrate. Imitation bronze foils may also have a tendency to smear slightly.

Foil Storage Conditions

Most standard foils can be stored safely under normal conditions, i.e., at temperatures between

5 degrees C (40 degrees F) and 20 degrees C (68 degrees F) and a relative humidity of between

30% and 70%. Care should be taken to avoid storage close to heating pipes and radiators, or in

direct sunlight.

Special care should be taken when storing low temperature grades. Rolls should not be

subjected to high temperature, or pressure, which could result in delamination. Rolls should be

stood on end, avoid stacking rolls horizontally.

Core Sizes

Foil is normally wound onto a 25mm (1") internal diameter cardboard core. Foils can be

supplied on 17mm (5/8"), 40mm (1.57"), 76mm (3") and 152mm (6") cores on special request.

Roll Widths and Lengths

Standard widths are 610mm, 640mm (depending on grade) and 1280mm. Standard lengths are

61m, 122m, 244m and 305m. Other lengths are available on request such as 183m, 500m,

1000m, 1500m and 2000m.

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Milford Astor

Ultra Violet (UV) cured varnishes are varnishes from the acrylate resin family that include a

photo-initiator. This reacts with the light from UV lamps, triggering a reaction which causes the

varnish to cure and dry instantaneously.

UV varnishes give a high gloss, abrasion-resistant finish. The instant drying also reduces

process time and makes coating much more compact.

For foil blockers, however, UV cured surfaces present particular problems owing to their

relatively low surface energy. Also, there is a tendency to include additives such as waxes and

silicones to increase the gloss or to act as a slip aid. Such additives can further reduce the

surface energy below that level necessary for successful foil blocking.

Another related problem is that of differential curing over coloured inks. Lighter coloured inks

will reflect back more UV light than dark ones, with the effect that the coating over a lighter

printed area cures faster. On a sheet with, for example, black ink and white areas, the varnish

can be properly cured over the white area and under cured on the black.

It is usually easy to get an indication of the degree of cure of a UV varnish. Simply wipe a

cotton wool swab moistened with an aggressive solvent such as MEK over the lacquer surface

and note the number of wipes taken to break through the lacquer. A properly cured varnish

should resist 10 double wipes.

A useful field method is to fold a piece of UV coated card in two and rub the surfaces together.

If they slip over each other without friction or resistance, it is likely that the surfaces are too

glossy for foil blocking. If there is some sticking or friction, the surface should be reasonably

foil-receptive, although other factors can, of course, prevent successful blocking.

Foiling Ultra Violet Cured Varnishes

Under Cured Varnishes

Blockers need to ensure that UV surfaces are properly cured. A UV varnish that is normally

blockable can give problems if it is under cured. In extreme cases, the varnish will be tacky, or

will smell strongly. In less obvious situations the foil will give poor adhesion or will blister,

known as "gassing".

Under curing can result from:

inadequate level of photo-initiators in the varnish. (They are expensive and economies *may have been attempted by the coater.)

excessive web speed, giving too little curing time.*

too few or dirty UV lamps, providing insufficient light for curing.*

too high a coating weight of varnish being applied.*

Recommendations for Successful Foil Blocking

Where difficulties are encountered, we suggest:

turning the sheet over and printing on the reverse. If the foil prints well, it confirms that *the UV surface is the problem.

oturning the sheet through 180 and print again to show up any differential curing and to *check if the problem lies with the dies or the press.

putting the sheet through the curing process again - this could well correct any fault due *to under curing.

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Milford Astor

Corona Treatment

Hitherto unprintable surfaces can be made blockable by Corona discharge treatment. However,

on UV surfaces, the effects of this treatment dissipate very quickly and the sheets should be

blocked within 12 hours at the most.

resisting the urge to increase blocking temperature as this usually exacerbates *the problem.

* that, if problems persist, samples are submitted to MILFORD ASTOR for evaluation.

Over Varnishing / Printing

With the increased use of foils for such applications as magazine covers, foil stampers should

be aware that not all foils will accept after varnishing be they conventional or UV. It is always

wise to test.

Venting of Dies

A common problem associated with the flat stamping die is flashing. Flashing occurs as a

natural process when all elements come together and causes the foil to transfer in unwanted

areas of your image. A common spot is the middle of an O or trapped area forming a

compressed air pocket.0

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0"

When the flat stamping die is etched to its common depth of 0.889mm, the inside of type may

be as shallow as 0.127mm. When air is heated and trapped, it will transfer one ton of pressure

per square inch, and transfer foil in undesirable locations.

Venting these areas by drilling a hole will let the heated air escape into the honeycomb.

How to Order Foils

Having selected the colour of your choice, refer to the industry application section for the grade

most suitable for your application.

Caution

The information in this catalogue is based on our experience and research as well as that of our

customers and is correct to the best of our knowledge. However, as we have no control over

user conditions, we cannot accept liability. You are advised to carry out your own testing.

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Milford Astor

Hot Stamping History, Manufacture &

Stamping Equipment

Hot stamping is the method of transferring a metallic or pigment finish from a

carrier strip, known as a foil, onto a substrate using heat, pressure and time.

Described here is the history of this process, the types of hot stamping foils

available today, the method of manufacture and other important factors to be

considered when foiling a product.

History

thOn July 24 , 1892, Dr Ernest Oeser first patented the production of both gold and

coloured stamping foils using 23 carat gold or bronze (copper and zinc) powder with

a dye to obtain the necessary colour. Both these foils were supported by a glassine

(paper) carrier strip.

This process had some limitations. Real gold was too expensive, being approx-

imately eight to ten times more costly than the vacuum metallised type foils used

today; and also bronze powder foils tarnished. Tarnishing is caused by the copper

oxidising, also the dyes available at that time were not completely light stable and

so the foils faded.

Other alternatives were considered and in the early 1950's vacuum metallised foils,

using aluminium were developed. This method is still used today and there is no

foreseeable change.

Foils Available Today

The range today includes genuine gold (23 carat), bronze powder, imitation golds

and metallic colours (vacuum metallised) pigments (flat, semi-gloss and gloss)

psychedelic, multi-colour, woodgrain and marble effects, brushed finishes,

chrome, leather look, clear, pearlescents and holographic.

Foil Selection

In hot stamping, a pigmented or metallised coated foil is transferred from a carrier,

usually polyester film, and fused to a substrate. Therefore, it is essential that the

pigmented or metallised coat be compatible with the material to be stamped. For

this reason, hot stamping foils are manufactured in various formulations designed

to give quality prints on a specific material. Also incorporated in the foils are

qualities such as abrasion resistance, oil and grease resistance, and chemical

resistance. Gloss, semi-gloss and matt finishes are available in a wide range of

colours.

Where formulation or colour is not satisfactory, custom made foils are obtainable.

Method of Manufacture

Vacuum metallised foils are commonly used today. A production roll of polyester

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Milford Astorcoating machine to have the wax release coating applied. This is then dried by radiant

heat before the film continues to the next coating to have the colour lacquer applied, after

which it is re-rolled and then placed into a continuous vacuum metallising machine. It

then goes to the third coating machine to have the adhesive coat applied. The foil is

inspected for pin holes and defects and is re-rolled into the length required by the end

user, normally 122m or 305m rolls.

The only difference between the manufacture of metallised and pigment foil is that

pigment foils do not have a vacuum metallised coating. Instead of the lacquer used for

gold and other metallic finishes a pigmented coating similar to ink is used.

From the diagram it may be seen that a foil comprises up to five layers and in each case

these may be varied to achieve the optimum result for different applications. Refer to

Diagram A below.

Carrier Film: There are basically six types, namely paper, cellulose, polypropylene,

acetate, polythene and polyester film. These vary in thickness from 12 micron (most

commonly used today) up to 50 micron. Most popular is 12 micron polyester. The heavier

carrier is used for stamping complicated plastic parts where a thin carrier tends to tear or

distort. Heavy carriers are also used when stamping large areas as this enables the foil to

lay flat on the job, thus facilitating the operation.

Release Coating: This is generally a wax which, as the heat is applied to the carrier, melts

and releases the other layers from the carrier. Many wax releases are available, ranging

from very easy to very tight. This can mean the difference between coverage on large

areas and obtaining fine detail.

Colour Coating: This varies in thickness. For fine definition a thin colour coat is

necessary; for large areas and where opaqueness is required a thick colour coat is used.

Vacuum Metallised Coating: Generally this does not vary, although in extreme cases a

heavier coating may be required.

Adhesive or Size Coating: This is probably the most important layer in the manufacture

of foil as it varies according to the substrate being stamped. For example, the adhesive

required for stamping paper is completely different from that needed when stamping

plastic bottles.

It is obvious that one foil cannot be selected to do all jobs. There is no universal foil that

will stamp all substrates. All the above details should be taken into consideration if the

best results are to be obtained.

Diagram A

CARRIER FILM

RELEASE COATING

COLOUR COATING

SIZE COATING

MATERIAL TO BE

HOT STAMPED

HOT STAMPING DIE

CARRIER FILM

RELEASE COATING

COLOUR COATING

METALLISED COATING

SIZE COATING

MATERIAL TO BE

HOT STAMPED

HOT STAMPING DIE

PIGMENT FOIL VACUUM METALLISED FOIL

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Milford Astor

Equipment Selection: Equipment selection will be determined by the design of

the article to be stamped, and production rate required.

Hand fed presses hot stamp up to 1200 parts per hour. Production from 1200 to

3000 parts per hour can be expected from a turntable equipped press, and even

greater output is possible from a clam action press, cylinder or roll-on press. The

basic types of presses are shown in Diagram C on page 39.

Vertical air-operated presses with a capacity of 0.25 to 6.0 tonnes. These are

mainly used for light duty stamping with metal dies or silicone pads. Vertical

presses compensate for variations in part thickness as they do not have a

fixed stop or mechanical linkage, the head of the press continues to travel

until it reaches the stamping surface and then builds up pressure to transfer

the foil to the part.

Air toggle presses with a capacity of 3 to 16 tonnes. The primary purpose of the

air cylinder on these presses is to actuate a mechanical linkage which exerts

greater pressure. Toggle action presses are capable of stamping parts up to

1200mm long x 600mm wide and have become popular owing to their capacity

and versatility. Another advantage of these presses is that with a fully opened

toggle, the head always descends to a pre-set position for uniform stamping.

This is dependent on a uniform wall thickness of the part.

Roll-on presses make possible a partial or complete stamping of the periphery

of cylindrical objects and also large flat contoured areas. These presses are air-

operated and incorporate a mechanical adjustment for die pressure. Air

ejection is available as optional equipment. Output of 800 to 2000 parts per

hour can be expected. Multiple colour stampings can be achieved on this

equipment providing the colours are on separate lines and a separation of 1.5

3mm is maintained between colours. This type of equipment is recommended

for hot stamping odometer and counter wheels, lipstick tubes, knobs,

television escutcheons, auto dash panels, plastic bottles and air conditioning

grills.

Clam shell mechanically operated presses with automatic feeding and

restacking of the product. These presses are used for such products as

greeting cards, letterheads and cartons.

Cylinder presses, based on the cylinder letterpress machine where the hot

plate is mounted to the moving bed usually have autofeed and restacking

facilities. These presses are used for foiling large sheets of paper and board.

Rotary letterpress machines, used for reel to reel pressure sensitive label

making are capable of running up to speeds of 300 meters per minute.

1.

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B 8.

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Milford Astor

HAND OPERATED PRESS CLAM ACTION PRESS TOGGLE ACTION PRESS

ROLL-ON PRESS FOR PLASTICS & MDF

FOILING SECTION

OF ROTARY LABEL

PRESS

CYLINDER HOT FOIL PRESS

WITH AUTO FEED

DIRECT ACTION

AIR OPERATED PRESS

Diagram CB

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Milford Astor

Foil Selection Guide

Metallic Foils - For GraphicsIt is always advisable to check availability of stock

Grade EDJAvailable in shades 000, 001, 027, 029

Easy Release FoilSuitable for coated and uncoated papers and boards, acetate, blockable UV inks and varnishes on platen and cylinder machines.Temperature range 100 - 120 degrees C.

Grade EFAAvailable in shades 001, 002, 006, 013, 017, 027, 028, 029

Tight Release FoilFine detail foil for smooth and coated paper stocks, leather and wood.Temperature range 110 - 140 degrees C.

Grade EFEAvailable in shades 000, 001, 003, 006, 013, 017, 025, 027, 029, 036, 091, 095, 097, 266

Easy Release FoilGeneral purpose foil for large areas, suitable for dry and smooth papers and boards. Ideal for fast running machines such as Bobst, Gietz and Heidelberg cylinder machines.Temperature range 80 - 130 degrees C.

Grade EFFAvailable in shades 000, 001, 006, 017, 027, 029, 036, 241, 257, 260, 261, 262, 266, 267, 268, 269, 299, 308

Medium Release FoilFine detail to medium solid work on plain papers and boards. Also suitable for blockable UV inks and varnishes.Temperature range 110 - 125 degrees C.

Grade 537Available in shades 002, 008, 029,And others on request.

Easy Release FoilGeneral purpose foil for large areas, suitable for dry and smooth surfaces. Ideal for fast running machines such as, Bobst, Gietz and Heidelberg cylinder machines.Temperature range 80 - 130 degrees C.

Grade GPAvailable in shades 385, 428, SM, SBR

Medium Release FoilVersatile foil offering medium release whilst producing fine clean impressions. Suitable for coated and uncoated stocks, most inks, lacquers and OPP laminates. Suitable for rotary, cylinder and platen machines.Temperature range 110 - 180 degrees C.

Grade UNCAvailable in shades 385, 425, 428, SM, SBR

Easy Release Foil (Overstampable)Versatile foil offering easy release, produces clean, sharp impressions. Suitable for coated stock and very suitable for uncoated stocks. Overstamps most coatings, inks and UV varnishes.Suitable for rotary, cylinder and platen machines.Temperature range 110 - 200 degrees C.

Grade OVPAvailable in shades 385, SBR

Medium Release Foil (Overprintable)Versatile foil offering easy release, produces clean, sharp impressions. Suitable for coated and uncoated stocks. Overstamps most coatings, inks and UV varnishes.Suitable for rotary, cylinder and platen machines.Temperature range 110 - 180 degrees C.

Grade LCFAvailable in shades 000, 385

Cold Foil (Free Radical Type)Fast release up to 300m/minute. Requires special “adhesive” which is readily available.

Milford Astor

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Milford Astor

Metallic Foils - For Graphics(continued)

Grade 700 SeriesAvailable in shades 385, SBR

Medium Release FoilSuitable for many types of papers and boards. Will print on most inks, lacquers and blockable UV varnishes. Suitable for use on platen and cylinder machines.Temperature range 120 - 160 degrees C.

Grade 045Available in shades 10, 23, 33, 46, 64, 70

Medium Release FoilSuitable for all types of smooth papers and boards. Will print on most inks and UV varnishes, for fine to medium print definition.Temperature range 110 - 150 degrees C,

Grade 100Available in shade 000Grade 101Available in shade 001

Medium Release FoilGeneral purpose foil for most types of stocks including plastic coated, Cello-glazed varnished & UV varnished papers and boards. General purpose foil for most plastics including PP, PE and ABS.Temperature range 110 - 130 degrees C.

Grade 140 000Available in shade 000Grade 140 300Available in a shade similar to 001

Easy Release FoilSuitable for parchment, leather, nylon polymer, satin acetate, all types of papers and boards for medium to large detail.Temperature range 100 - 130 degrees C.

Grade 030Available in shades 10, 14, 23, 26, 33, 60, 62, 64

Medium Release FoilSuitable for credit card tipping. General purpose, will suit most stocks.Temperature range 110 - 140 degrees C.

Grade GFEAvailable in shades 095, 098, 107, 108, 123, 127, 241, 257, 260, 261, 262, 267, 268, 269, 277, 299, 308

Easy Release FoilGeneral purpose foil for large areas, suitable for dry and smooth papers and boards. Developed for scuff resistance of embossed image areas. Ideal for fast running machines such as Bobst, Gietz, and Heidelberg cylinder machines.Temperature range 80 - 120 degrees C.

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Milford Astor

Metallic Foils - For Plastics, Leathers & FabricsIt is always advisable to check availability of stock

Grade EFFAvailable in shades 000, 001, 006, 017, 029, 036, 241, 257, 260, 261, 262, 266, 267, 268, 269, 299, 308

Medium to Tight Release FoilSuitable for ‘tipping’ conventional plastics such as styrene and PVC.Temperature range 110 - 130 degrees C.

Grade 591Available in shades 000, 001

Medium Release FoilSuitable for PVC, leather and some fabrics.Temperature range 110 - 125 degrees C.

Grade 595Available in shades 000, 001, 011

Easy Release FoilSuitable for PVC, leather and some fabrics.Temperature range 110 - 125 degrees C.

Grade 100Available in shade 000Grade 101Available in shade 001

Medium Release FoilAn extremely flexible foil suitable for most plastics including polypropylene, polyethylene, ABS and styrene. Excellent high temperature performance.Temperature range 130 - 150 degrees C.

Grade 140 000Available in shade 000Grade 140 300Available in a shade similar to 001

Easy Release FoilSuitable for parchment, leather, nylon polymer, grained book cloth, satin ribbons and all types of papers and boards for medium to large detail.Temperature range 100 - 130 degrees C.

Grade M 160 SeriesAvailable in shade 000 and a shade similar to 029

Medium Release FoilVery flexible foil for rigid plastics such as ABS and styrene, but especially for polypropylene and polyethylene. High resistance to diluted acids. Fine to medium coverages, metal die.Temperature range 120 - 200 degrees C.

Grade YSAvailable in shades 000, 001

Medium Release FoilSuitable for some PVC and polyolefins.Temperature range 110 - 130 degrees C.

Grade PS GG2Available in a shade similar to 001

Medium Release FoilVery universal quality for the plastics industry. Suitable for use on PS, PVC, ABS, SAN and PET. Excellent for ‘tipping’ eg. Shampoo bottles.Temperature range 110 - 200 degrees C.

Grade PT SLIAvailable in shade 000

Tight Release FoilSuitable for roll on application using metal or rubber dies for blown bottles, PE and PP.Temperature range 120 - 200 degrees C.

12

Milford AstorMatt Pigment FoilsIt is always advisable to check availability of stock

Grade CDFAvailable in shades 1, 3, 4, 6, 9

Date Coding FoilVersatile product. Applications include packaging films such as polyethylene, cellophane, right through to some label stocks.

Grade CDF A SeriesAvailable in shades 1, 9

Date Coding FoilSpecially formulated, gives extra adhesion for foil tablet packs, foiled Easter egg packs, for use when other coding foils scratch off.

Grade CDF P SeriesAvailable in shades 1, 6, 9

Date Coding FoilHigh speed application ideally suited to low melt packaging films. Polyethylene, vinyl and frozen food bags.

Grade CDF 4 SeriesAvailable in shades 1, 6, 9

Date Coding FoilFine detail, suitable for varnished pharmaceutical labels, cheese packs and other vacuum packed foods.

Grade CDF 5 SeriesAvailable in shades 1, 6, 9

Medium Release FoilSuitable for large area prints, gives this series a wide scope of applications, including date coding.

Grade CDF PH SeriesAvailable in shades 6, 9

Cold Stamping FoilUsed by bakeries to mark styrene bread bag seals.

Grade DAGAvailable in shades 023, 024

Scratch Off FoilSuitable for gloss boards, inks, UV varnishes, plastics such as credit cards, phone cards and game cards. Temperature range 110 - 130 degrees C.

Grade DAHAvailable in shade 023

Medium to Soft Release FoilBronze foil that can be overprinted. Resistant to smudge. Suitable for a very wide range of substrates. Temperature range 110 - 150 degrees C.

Grade DBAAvailable in shades 001, 016, 017, 018, 021, 025

Tight Release, Fine to Medium DetailSuitable for most coated or smooth papers and boards. Also suitable for nylon, styrene and PVC.Temperature range 110 - 150 degrees C.

Grade DBFAvailable in shade 021

Tight Release FoilExtra fine detail foil. Ideal for coated papers and boards.Temperature range 110 -150 degrees C.

Grade DBJAvailable in shades 023, 024

Medium to Soft Release FoilBronze powder type. Suitable for a very wide range of substrates, including polyurethane and polypropylene. Take care, this foil could corrode and rub off if in contact with carbon and acidic substrates.Temperature range 110 - 130 degrees C.

Grade DCBAvailable in shades 001, 005, 010, 012, 018, 021, 025, 031, 073, 171, 178, 180, 184, 205, 206, 625, 626, 632

Easy Release FoilSuitable for a large range of substrates including coated and uncoated stocks, ABS, acetate, acrylic, cellophane and styrene.Temperature range 100 - 150 degrees C.

Grade DHEAvailable in shades 001, 012, 018, 021

Easy Release FoilSuitable for a large range of substrates including coated and uncoated papers, boards and plastic films. Temperature range 100 - 150 degrees C.

Grade LTAvailable in shades 1, 3, 4, 6, 9

Easy Release FoilSuitable for a large range of substrates, including coated and uncoated stocks.Temperature range 100 - 130 degrees C.

13

Milford AstorGloss Pigment Foils For PlasticsIt is always advisable to check availability of stock

Grade A SeriesAvailable in B12A White, B10A Black, B24A Yellow

Medium Release FoilSuitable for polyethylene, PVC, acrylic, ABS, acetate, polypropylene, metal or rubber dies.

Grade B SeriesAvailable in B233PR Black

Fine Release FoilDesigned for polypropylene and polyethylene, metal dies.

Grade DFJAvailable in shade 021 Black

Tight Release FoilSuitable for ABS, styrene, acetate, nylon and PVC.Temperature range 110 -130 degrees C.

Grade PP1Available in shades1016 White4728 Dark Red6721 Dark Blue7028 Dark Green9110 Black

Medium Release FoilSuitable for polyethylene, polypropylene, vertical and roll on presses.Temperature range 120 -155 degrees C.

Grade PS1Available in shades1041 White4088 Dark Red6061 Light Blue6237 Dark Blue9001 Black

Medium Release FoilSuitable for acrylic, styrene and ABS.Temperature range 135 -155 degrees C.

Grade Y SeriesAvailable in shades064 White93 Black

Tight Release FoilDesigned for polypropylene and polyethylene but also suitable for styrene, ABS, metal dies.Temperature range 110 - 150 degrees C.

Grade SV SeriesAvailable in shades59724 Black56759 Blue54757 Red

Quick Release FoilDesigned for stamping onto soft vinyl, such as IV bags and blood bags.

For Shades Available Request Samples

14

Milford AstorSemi-Gloss Pigment Foils For PlasticsIt is always advisable to check availability of stock

Grade Semi-GlossAvailable in shadesSI9 230 WhiteSH9 231 BlackSA 9232 RedSC9 234 YellowSB9 237 OrangeSD9 238 Dark GreenSD9 233 Light GreenSE9 239 Dark BlueSE9 240 Light BlueSG9 241 Brown

Easy Release General Purpose FoilThis low temperature foil shows excellent results on soft PVC and polypropylene but is also suitable for most other plastics using metal dies. Rubber dies can be used when required. This grade is ideal for a second surface on clear plastic. Also suitable on some leathers.Temperature range 110 - 200 degrees C, depending on the type of plastic being stamped.

Grade DFJAvailable in shade 021

Easy Release FoilSuitable for coated and uncoated papers, credit card tipping, styrene and ABS. Not suitable for plasticised surfaces. Can be used as an alternative to DFD. Temperature range 110 - 130 degrees C.

Grade DFDAvailable in shades 021, 094, 096, 191, 192, 193, 194, 226, 227, 228, 479

Medium Release FoilTransparent gloss foil, excellent fine detail and large area properties on gloss white paper and acetates. Substrate colours cause colour change owing to transparent nature of foil, therefore it is suggested for use on gloss white substrates only. Can be used with other colours to give special effects. Temperature range 110 -130 degrees C.

Grade FFFAvailable in shade 000 (clear)

Medium Release FoilUsed to increase gloss level on printed surface, for highlighting.Temperature range 110 - 130 degrees C.

Grade CCAvailable in shade 021

Tight Release FoilSuitable for credit card tipping.Temperature range 110 - 130 degrees C.

Gloss Pigment Foils (for a variety of applications)It is always advisable to check availability of stock

For Shades Available Request Samples

15

Milford Astor

Grade DFEAvailable in shades 109, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 125, 214, 220, 471, 472, 474, 475, 621, 622

Medium Release FoilSuitable for coated and uncoated papers and boards.Temperature range 110 -120 degrees C.

Grade DFFAvailable in shades 125, 214, 474, 475, 621

Easy Release FoilSuitable for coated and uncoated papers and boards.Temperature range 110 -120 degrees C.

Pearl FoilsIt is always advisable to check availability of stock

16

Milford Astor

Metallic Foils for Rotary & Cylinder PressesIt is always advisable to check availability of stock

Grade GPAvailable in shades 385, 428, SM, SBR

Medium Release FoilVersatile foil offering medium release while producing fine clean impressions. Suitable for coated and uncoated stocks, most inks, lacquers and OPP laminates. Suitable for rotary, cylinder and platen machines.Temperature range 110 - 180 degrees C.

Grade UNCAvailable in shades 385, 425, 428, SM, SBR

Easy Release Foil (Overstampable)Versatile foil offering easy release, produces clean, sharp impressions. Suitable for coated stock and very suitable for uncoated stocks. Overstamps most coatings, inks and UV varnishes.Suitable for rotary, cylinder and platen machines.Temperature range 110 - 200 degrees C.

Grade OVPAvailable in shades 385, SBR

Medium Release Foil (Overstampable)Versatile foil offering easy release, produces clean sharp impressions. Suitable for coated and uncoated stocks. Overstamps most coatings, inks and UV varnishes.Suitable for rotary, cylinder and platen machines.Temperature range 110 - 180 degrees C.

We have a seperate article written on “Rotary Hot Stamp Process”. It is available on request.

17

Milford Astor

We are specialist suppliers of optical variable devices (OVD’s) for brand authentication

and security applications. Bank note and high security markets include passports, ID

systems, government documents, stamps, travellers’ cheques, gift vouchers, travel

tickets, event tickets and cheques. Brand protection markets include licensed

merchandise, pharmaceuticals, automotive parts, fashion industry and software

industry.

Products include holograms-2D, 3-D, transfer foils and labels, tamper evident

holographic labels, holographic tear tapes, holographic hot stamp foils and holographic

thread.

Specialty Foils

Security - Holographic

Packaging - Holographic

Holographic film, laminates and papers find applications in label manufacture,

packaging, confectionery, snackfood, detergent, health care, cosmetics, wine and

spirits, display, point of sale and publishing.

Foils for Timber / Medium Density Fibreboard

Specialty foils for timber products such as picture frames, trophies, furniture, kitchen

cabinets, etc, are available in a range of patterns and colours including solid colours,

woodgrains, marbles and special effects. Pattern and colour matching service is also

available.

Washable Foils for Textiles and Apparel

Cold Foil

For the textile and apparel industries, there is a range of washable hot stamp foils for

garment care labels.

A range of fabrics for garment care labels is also available. These include white, pearl

and black nylon, pearl and matt white non-woven polyester.

This series of metallic foils requires no heated die. Requires application in conjunction

with a free-radical cold foiling adhesive which is UV activated. Generally used on web

fed machinery such as Gallus, Nilpeter, or any UV curing printing machine.

We have a separate article written on “Cold Foil Application”.

It is available on request.

We have a seperate article written on “Cold Foil Application”. It is available on request.

18

Milford Astor

Quick Application Reference

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19

Milford Astor

Hot Stamping Operation

The hot stamping operation is a function of four variables: die temperature, dwell time,

pressure and stripping time. (Stripping time is not so important in graphic arts

application).

Die Temperature is generally controlled by a thermostat or temperature controller,

which is capable of maintaining head heat under normal cycle speeds in a range of 100

- 170 degrees C. Fluctuations from the set temperature should not exceed plus or

minus 5 degrees C.

The temperature control should be set only high enough to bring the foil and the part to

a plastic state. Excessive heat will cause decomposition of the resin used in the foil

and prevent its adhesion to the part. Other indications of excessive heat are flaking

where the foil bridges between borders (or leaves fuzzy edges which flake off when

rubbed), discolouration, and dullness of the stamping. Since the correct plastic

temperatures of resins are a known factor, charts have been compiled giving the

proper temperature settings for the various foil formulations and plastic materials to be

stamped. These charts should be used in setting temperatures on new jobs.

Normally, only minor adjustments from these temperatures will be necessary on a

specific job. Experience gained with these settings will indicate that slight variations

from the standard settings can be controlled by the dwell timer rather than by changing

the temperature control.

Care should be taken to ensure good contact between the die and the head of the

press to prevent heat loss and maintain adequate heat flow. Use of higher

temperatures to increase the depth of penetration of the die, to complete transfer

on an uneven or improperly supported part, or to increase wear resistance should be

avoided. Depth of penetration should be a function of pressure, not heat.

Dwell Time is the second variable. To determine the proper dwell setting, start with

the shortest dwell and increase the time in small increments until a full transfer is

achieved. The shortest dwell should be measured from the time the die comes in

contact with the part and not from the zero reading on the timer, since the timer starts

when the head begins its downward stroke. In recording dwell time for future use, the

dwell time should be measured from initial contact, since head speeds vary from press

to press.

As dwell time is a factor in determining the rate of production, it is obvious that the

fastest dwell setting is desirable. To accomplish this, heat should be raised by

increments of 5 - 10 degrees C. Once the heat has stabilised at the new setting,

reduce the dwell time to just above the point of incomplete transfer.

Pressure determines the depth of penetration of the stamp below the surface of the

part. Of equal importance is the matter of head velocity which controls die impact.

Also to be considered is a mechanical depth stop control.

On toggle presses the depth of penetration is set by raising or lowering the work-

table. When the toggle is closed, the head will always stop at the same point.

20

Milford Astor

On direct-acting air presses, the depth of penetration is set by raising or lowering the

work table (on some presses of this type, the entire head of the press can be lowered

to achieve the same effect).

With metal dies, use of low head pressure to control depth of penetration results in

changing dwell times and erratic transfer. To obtain a mechanical stop and minimise

head speed variations, which affect dwell time, close to the maximum recommended

air pressure should be used. This is normally 80 - 100 p.s.i. and in most cases never

below 50 p.s.i. Note that air pressure at the press should be set approximately 10

p.s.i. below line pressure to eliminate fluctuations due to the on-off cycle of the

compressor. Such fluctuations would result in erratic timing. Speed applications

should be set high enough to achieve the penetration and slow enough to prevent

damage to the part and die.

Rules for tipping raised areas with silicone rubber pads are different to those for

metal dies because the head velocity must be reduced to give a light 'kiss'

impression. Head stop control also is extremely important since excessive repetitive

compression of the silicone pad at high velocities will result in poorer quality

stamping and more rapid breakdown of the silicone pad. Use of make-ready to build

up areas of no transfer once the head stop control has been set, enabling the silicone

pads to just contact the part, is preferable to a pressure increase. This is extremely

important with plated metallic foils since excessive pressure will result in a dull finish.

Stripping Time is the fourth variable. After the hot die has lifted off the part,

sufficient time must be allowed for the transferred material to cool and harden on the

part. The carrier is now stripped from the part and the transfer is complete.

Obviously, stripping the carrier while the resin is still in the plastic state will result in

incomplete transfer or pulling the pigment and even some resin away. Proper

adjustment of the foil stripper bars can assist this situation.

In the case of a travelling foil feed, as the die starts its downward motion, the stripper

bars push the foil ahead of the die onto the part. As the die continues downward, the

stripper bars hold the foil onto the part until the head returns. As the compressed

springs are released, the stripper bars rise, separating the foil from the part. Most

machines now have foil feed delay timers fitted.

If longer cooling time is required, the foil feed delay time should be increased. On

machines without foil feed delay timers, the stripper bars must be set lower. The

proper cycle should be set by laying the foil onto the part by hand. Then, the foil

should be threaded through the press with the stripper bars adjusted so that the foil

passes 12mm below the die. After making a test stamping, the stripper bars should

be lowered until transfer is complete. In extreme cases where stripper bars cannot

be lowered sufficiently, the foil feed should be slowed down.

Conclusion: The hot stamping process is ideally suited to the decoration of many

products. Being a dry printing process, parts can be packed immediately at the

machine. Stampings are permanent and inexpensive. As it is a simple process,

Operator training is minimised. By following the procedures outlined in this

catalogue, trouble-free hot stamping can be achieved.

21

Milford Astor

Bottle Stamping & Roll-on Stamping

The technology matches the workpiece

The mechanics of the stamping process vary depending on the type and shape of the

workpiece to be enhanced. The most important difference between the various

design principles is the method by which the pressure is transferred from the

stamping tool to the workpiece. On this basis the various methods are vertical

stamping, circumferential marking, inflation stamping for bottles and similar hollow

bodies and roll-on stamping.

� Vertical Stamping

The presses for this process, in which the stamping tool moves vertically up and

down at each stroke, are generally termed “vertical presses” in enhancement of

plastics. Depending on the system used to generate the pressure they are

divided into mechanically, pneumatically and electromagnetically operating

vertical presses.

In the pure vertical stamping process

flat parts can be stamped using a

flat tool, convex parts using a

corresponding shaped concave tool

and concave parts using a convex tool

to match the workpiece. With

curvatures, the stamping angle should o

not exceed 90 . Up to 25% of the

circumference of a cylindrical part

can be enhanced using vertical

stamping provided the tools match the

workpieces. These are maximum

figures which only apply if the radii are

sufficiently large.

� Circumferential Marking

Hot stamping can be performed “all around the workpiece” on presses which

are similar in their basic design to vertical presses. Special holding fixtures,

rotating supports and horizontal guides for the workpiece complete the

stamping presses for circumferential marking. The special feature of this

process is that a cylindrical workpiece (can, sleeve, tube, screw cap) is rolled

under a flat stamping tool and the foil is stationary.

The back pressure is produced by two support rollers on which the cylindrical

workpiece rotates. The support rollers and the workpiece holding fixture

(location pin) together form the rolling device and are carried forwards

horizontally by means of a drive system (support). The forward

1.

2.

22

Milford Astor

drive is controlled pneumatically or electrically while the roll-on movement is

usually mechanically controlled.

Numbering wheels, too, are normally stamped by this method. Special

equipment allows extremely accurate automatic positioning of the injection

moulded part.

Using this process it is also easy to stamp

slight conical parts, the die being shifted

somewhat on the workpiece to even out

the difference in the roll-on speed of the

large and small diameters.

o oParts with a conical angle of over 1 to 2

must be positioned on a special roll-on

device, which permits the workpiece to

rotate around the imagined apex of the

cone. Parts which are strongly conical

cause difficulties for circum-ference

mark ing, because the d i f ferent

circumferential speeds of the large and

small diameters make it almost

impossible to foil.

In circumferential marking the location of

the stamping die must always be in

register with the hartline of the moulding.

The lowest temperature for the platen and stamping tool during the working

stroke is accurately determined by the depth stop. This device restricts the

downward motion of the pump rod in pneumatic systems when pressure builds

up in the cylinder by means of a mechanical stop.

In circumferential marking the roll-on device is moved from one end setting to the

other end setting. The roll-on speed is controlled and the distance rolled by a

time switch or limit switch. The stamping process begins, as soon as the front

edge of the heated tool comes into contact with the circumference of the

workpiece. It continues until the rear end of the stamping tool is reached.

When the workpiece makes initial contact or leaves the stamping tool,

excessively deep or insufficiently deep stamping may occur, depending on the

stamped image. This can be counteracted by attaching a front or end piece

made from thermally insulating material (laminated plastic) at the beginning and

end of the stamping tool. A corresponding lateral mask of insulating material

helps to support the stamping die on the workpiece and also prevents the tool

sinking too deeply into the surface of the workpiece.

Parts which need to have the stamped image matched precisely with a functional

edge or another printed image, are rolled under positive drive. For this a pinion is

attached on the axle of the workpiece holding fixture. The diameter of the

pitched circle of this pinion coincides with the diameter

23

Milford Astor

under the stamped image. When

the roller device is moved forward

the pinion meshes in a gear rack

and drives the workpiece.

With positive drive as with rolling

under friction, the line connecting

the axes of the supporting rollers o

should form an angle of approx 90

with the axis of the workpiece.

Bottle Stamping

This variation of hot stamping was

developed for hollow bodies, in

which the back pressure required

for hot stamping cannot be

produced by mechanical means

Hot stamping is carried out in this case in a two part mould, which fits exactly

round the external contours of the plastic bottle. The bottle is laid in the lower

half of the open mould. The upper half of the mould contains the stamping tool,

which must also be matched exactly to the contours of the bottle, and the guides

for the stamping foil.

The hot stamping process is as follows: the two halves of the shroud are closed,

and the bottle is inflated through a mouthpiece via a control valve using

compressed air at approx. 8 to 10 bar. The expansion of the bottle causes the

wall of the bottle to be pressed against the stamping foil and the stamping tool

located above the bottle. The internal pressure in the bottle thus generates the

printing pressure for the hot stamping. The contact is ended by letting out the

compressed air. The shroud can now be opened and the hollow body removed.

Roll-on Stamping

In this process a stamping tool in the form of a (normally externally) heated

silicone rubber roller is rolled over a workpiece on which stamp foil has been laid;

in this way lines, letters and decoration, which are embossed on the moulded

parts (relief injection moulded parts) can be coated with stamping foil as also can

flat surfaces and continuous sections.

A typical example of the roll-on method is the rotation of a round roller over a flat

surface, in which only a narrow continually moving zone is in contact (“line

contact”). The contact time is usually very short and has to be compensated for

by higher operating temperatures, and by the use of particularly easily releasing

stamping foils.

The workpieces are placed on a moving table or on a conveyor belt and are

moved forward at constant velocity under the stamping roller or stamping wheel.

4.

3.

because of their shape and elasticity.

24

Milford Astor

The roll-on method is not limited, however, to flat objects. This process is

suitable, in principle, for any workpieces on which a stamping foil can lie

without creasing. This includes, for example, cylindrical, oval, square edged

and other convex bodies with parallel side lines running in the direction of the

stamping roller axis.

Using appropriately fitted stamping roller or wheels, even grooved profile

strips or external radii can be continuously stamped by the roll-on method. In

such cases excessive differences in the diameters in stamping wheels

should be avoided, since large differences in the circumferential speeds

cause folding in the stamping foil. With workpieces of this kind it is

recommended that very deep and raised parts of the cross section be

enhanced in separate operations. The same applies for very pronounced o

curvatures, where a stamping angle of 120 would be obtained, for example, o

by using two stamping wheels in series each at 65 . The applicability of this

technique depends naturally on the

decoration of the stamping foil

selected.

Typical examples of the use of the

roll-on process are housings for

sound and television equipment,

frames and furniture str ips,

windscreens for motor vehicles and

other similar parts. In other words,

workpieces which are not suitable

for vertical stamping because of

their shape or for which the

necessary printing pressure cannot

be economically achieved in vertical

printing presses because of their

large surface area.

In this variation of the hot stamping

process the design of the workpiece

holding fixture requires

much care.

Workpiece holding fixture for the roll-on

stamping of the front panel of an

instrument with windows: 1 – front

piece, 2 – core pieces, 3 – end piece,

each at the height of the workpiece, set

2mm away from the workpiece.

much care.

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Milford Astor

Thus, for example, front pieces must be positioned in front of the tool so that

the stamping roller is set down on a connected surface and not on the edge of

the workpiece. In this way a clear imprint is obtained and the silicone

stamping tool is protected. Front pieces also result in the longitudinal folds in

the stamping foil, which form when the stamping roller descends, being first

rolled flat. End pieces behind the workpiece have the effect of shifting the

problem zone when the stamping roller is lifted from the workpiece. Front and

end pieces must be at the exact height of the workpiece, as must the so-called

core pieces in the workpiece holding fixture which are used to fill large cutouts

(“Windows”) in the workpieces. Core pieces also help to prevent folds

forming in the stamping foil.

A particular variation of this process is roll-on stamping using a cylindrical

stamping tool, the circumference of which is covered with characters,

symbols, numbers, etc. This is used in particular for marking cables, plastic

pipes, for hot stamping continuously running packaging sheets, or for

decorative purposes.

TOOLING

2Part

Nest

Part

Support

5

Die

Top Shroud

Bottle

Bottom

Shroud

Air

1

3

Part

Mandrell

Top surfaces

horizontal

Diagram B

Part

Lay

4

C

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Milford Astor

Hot Stamping Substrates

Printing techniques concern the reproduction of written, pictorial and ornamental

images on paper, cardboard and similar materials. But hot stamping however is an

application well outside this definition. All wettable materials paper and board,

thermoplastics and duroplastics, leather and textiles, wood and many other materials

can be printed, stamped, coated, or refined with hot stamping foils: In brief, they can

be finished to a specification.

Cast Coated and Machine Coated Papers and Boards

These are among the least troublesome of print carriers and do not restrict the choice

of stamping foil. With cast coated types, pressure and temperature activate

adhesion of the surface coating, which benefits hot stamping. This intrinsic adhesive

action only has an undesirable effect in types coated both sides by causing the

printing sheet to stick to the packing. In such cases, easy release stamping foils,

which permit low stamping temperature, must be used in order not to activate the

intrinsic adhesive effect of the material. The make-ready should be covered, if it

consists of a plastic material such as Makrolon, etc., with a protective sheet. Easy

release types of stamping foil have proved more suitable for stamping solid areas

since compression force applied to the cardboard coating can be reduced. It can be

observed that the coating is pressure sensitive particularly in the case of cast coated

types with a relatively high unit weight, which can produce poor results in stamping

solid areas due to the formulation of shadows and small blemishes.

Papers and Boards with Smooth or Rough Surfaces

Untreated papers and boards are suitable for hot stamping as long as they are not

synthetic papers. A smooth surface structure permits great latitude in the use of

tight release or easy release stamping foils. The rougher the surface, the less the

latitude with the tight release types and the greater the latitude with the easy release

types of stamping foils. Easy release types of stamping foil come away from the

carrier under relatively slight temperature changes. Their adhesive layer is in most

cases formulated to produce a high bonding effect. Of the easy release types of

stamping foil, those with a thick, elastic coating, such as grade EFE and 140 should

be selected, to cover rough surfaces well. The degree of fineness of hot stampings

can suffer from rough surfaces, and the easy release types are necessary for this

purpose.

Lacquered, Coated or Foil-laminated Papers and Boards

Papers and boards with metallic plastic coatings, particularly involving the use of

polyolefins such as polyethylene, accept stamping foil only with great difficulty.

Particularly high demands are placed on the adhesion of the stamping foil by boards

that have been foil-laminated or specially coated with polypropylene, particularly with

areas of solid print or similar decoration. However, other surface coatings, such as,

eg. Chromolux Metallic or Chromolux Colour, also limit the use of hot stamping. Such

print carriers tend to gas quickly. Solid areas stamping should therefore be applied

preferably with rotary or cylinder stamping machines.

However, on all these print carriers hot stamping in the form of lettering, lines and

small ornamental areas can be generally done without trouble using any machine.generally be

Chromolux Metallic or Chromolux Colour, also limit the use of hot stamping. Such print carriers tend to gas quickly. Solid areas stamping should therefore be applied preferably with rotary or cylinder stamping machines.

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Milford Astor

It should also be borne in mind that subsequent damage from plasticisers can occur

not only with soft PVC foils, but also with PVC coated self-adhesive papers (plasticiser-

resistant stamping foils).

Leather Fibrous Substrates, Soft PVC Foils

Leather fibrous substances are normally less problematic printing materials. The

fineness of the hot stamping that can be executed is largely governed by the grain of

the surface. A rough surface of coarse grain refracts light, which can make fine

lettering illegible (“filling”). It should also be remembered that a good surface

covering is extremely difficult to obtain on coarse-grained materials since the grain

cannot be smoothly printed in the normal stamping procedure. Although very fine

lettering can be produced with tighter release stamping foils, it should not be done

below a certain limit. Soft PVC can also be hot stamped without much difficulty with

selected foils. With the normal stamping method the same restrictions apply as in the

case of leather, fibrous substances and grained, nitrocoated papers. For grained PVC

materials embossing is by high-frequency stamping methods, in which the area is

previously smoothed by high frequency embossing.

Creasing of Hot Stamped Impressions

If a crease or fold extending over the hot stamping impression is to be made in the

substrate, eg. in the production of folding boxes, it is absolutely essential to check

the “creasability” of the applied stamping foil in each case. It is not sufficient to

test the creasing behaviour of the “cardboard or paper” base material on principle.

All further finishings, such as offset printing, lacquering or foil lamination, affect the

creasability of a material. The same comments also apply to the “hot stamping”

finishing stage. We recommend that you check the creasability of the hot stamped

impression and substrate, at the beginning and during the production run. An

optical evaluation is not enough to ensure quality given the extreme stresses to

which a surface is subjected during folding and creasing, and in the carton gluing

machine after treatment. For this reason creasability must be supplemented by

passing the specimen through a gluing machine. Hot stamping near an area which

has to be later folded or creased must be subjected to the most thorough care and

quality checks.

28

Milford Astor

Magnesium Die

Stamping Dies

The collective term is used to cover all functional parts which transfer heat and

compressive force to the stamping foil and the workpiece during the hot stamping

process and whose surface layout determines the stamping image. In the wider

sense this also includes die plates, stamping rollers and wheels for large area transfer.

In the narrow sense we mean by stamping tools (so-called stamping dies), plates with

a surface design in three dimensions, the raised parts of which transfer the active

layers of stamping foil on to the surface of the workpiece.

Depending on the type of hot stamping process used (vertical stamping,

circumferential marking, bottle stamping, roll-on stamping) and the surface design of

the workpiece (plain, convex, concave), the stamping components on the stamping

die can lie on a flat, convex or concave plane. The difficulties in manufacturing curved

stamping tools do indeed have an effect on the price, but the basic demands placed

by hot stamping on the tools are much the same for all the different types.

Depending on the material used, the tools are divided into metal stamping dies and

silicone stamping dies.

Metal Stamping Dies

There are two different basic

manufacturing methods: etching

and engraving of stamping tools.

The materials suited for the

manufacture of etched stamping

tools are copper, magnesium, brass

and steel. The particular advantage

of etched stamping tools is that

the manufacturing method is

inexpensive, based on etching from

a photographically reproduced

original. Since the costs are based on

the size of the surface area of the

tool, it is an inexpensive method for

producing difficult motifs, eg.

ornaments, lines, large blocks of text.

Subsequent engraving work is

sometimes necessary.

Etched Coper Die

of text.

Etched Copper Die.

Etched Magnesium Die.

29

Milford Astor

Engraved Metal Stamping Tools

Engraved steel stamping die matched to

the workplace on two planes.

Stamping tools on which are placed strict requirements for accuracy and stability

are manufactured by precision engraving from brass or steel.

The hardness of brass is sufficient to make this material suitable for hot stamping

even in large runs. On the other hand brass is not as hard as steel and can be

worked more easily and is therefore also suitable for tools where a lot of material

has to be cut away from the blank, because of the design, eg. stamping tools for

vertical stamping and convex and concave parts and for bottle stamping.

Steel is becoming increasingly popular as a material for engraved stamping tools.

Steel stamping tools should be made from low distortion tool steel so that they

remain true to size even after hardening.

A hardened steel stamping die shows hardly any wear under normal load and is

therefore suitable for large runs. Since steel can be worked with particular

precision, special stamping tools for geometrical instruments, rulers and number

wheels should also be made in steel, as should stamping equipment with

interchangeable parts, such as type brackets.

Any slight damage on metal stamping tools, eg. caused by foreign bodies, can be

repaired by the specialist.

Where dies are purchased, the die vendor should be supplied with a sample, a print

or drawing of the part, and black and white artwork of the impression. The print

should be used for reference only and the part for matching. Artwork should be

drawn 1:1 for large dies and 2:1 for smaller dies. Photographic positive can be

substituted for black and white artwork. It should be noted that the sharper the

artwork, the sharper the die.

Engraved steel stamping die matched tothe workpiece on two planes

30

Milford Astor

Silicone Rubber Pads

Silicone Rubber Pads are used to hot stamp onto raised surfaces of plastic

mouldings, this process is called “tipping”. Silicone rubber is used because it can

withstand heat, and being elastic it will compensate for variations in the height of the

moulding. The raised surface may be a logo, lettering or a surround of a panel.

These are formed by engraving the plastic moulding die and should allow the raised

surface to be a minimum of 1.5mm high. Silicone rubber is available in thicknesses

from 1/32 to 1/4 inch bonded to either steel or aluminium of 1/32 or 1/8 inch

thickness. The thickness of the silicone selected will depend on the amount and

height of the raised area and the degree of distortion of the part. The following guide

to maximum desirable penetration by the part is suggested.

Rubber Thickness Penetration

0.794mm (1/32 inch) 0.254 - 0.397mm (1/100 - 1/64 inch)

1.588mm (1/16 inch) 0.397 - 0.794mm (1/64 - 1/32 inch)

3.175mm (1/8 inch) 0.794 - 1.588mm (1/32 - 1/16 inch)

The deeper the penetration, the shorter the life of the silicone rubber. Sharp edges

on the plastic part should be avoided as they will cut into the pad and reduce its life.

Die temperatures of 150 - 200 degrees C (thermostat setting 200 - 250 degrees C) are

necessary. It should be noted that excess heat will cause delamination of the rubber

from its aluminium base and mechanical abuse will quickly damage the rubber face.

Correct usage of silicone rubber will result in a life of up to 20,000 - 30,000

impressions, increased brilliance of gold and silver foils, improved adhesion and

surface hardness, lower rejects, increased production and more uniform and

attractive prints.

Note that rubber pads should not be used carelessly to overcome poor alignment

between die and fixture bed; or to compensate for excessive sinks and distortions

caused by poor design and moulding techniques.

Moulded Silicone Rubber Dies

Moulded Silicone Rubber Dies are also used for first and second surface stamping of

plastic items, which are unusual in design, and where a 'laid on' foil effect rather than

an 'embossed' effect is required. They can also compensate, to a degree, for

irregularities in the part being stamped.

Tooling

Three basic materials are used for fixtures: epoxy, aluminium and steel (not

hardened). Fixtures serve two purposes. The first is to position the part

accurately under the stamping die. The second is to support the part properly

when pressure is applied by the die. Lack of proper support will allow the part to

shift out of position, causing stamping of uneven depth and missing prints. Poor

support may also result in cracking or crazing of the plastic and / or foil shown in

diagram B on page

see

.See diagram C on page 39.

31

Milford Astor

Epoxy Fixtures are used mostly by stampers who must contend with short runs or

complex shapes. These fixtures usually are cast directly from the part to be stamped

and the back is either sanded or milled flat. They are also used to match irregular

surfaces or contours. Epoxy fixtures require continuous 'make-ready' throughout the

production run because they continually flatten due to the pressure and heat exerted

by the die. The term 'make-ready' refers to the use of tape, cork, rubber or other

materials to build up depressed areas of the fixture to properly support the part when

die pressure is exerted. See Make-ready, page

Aluminium Fixtures are often used in the industry because of their ease of

workability, and because of reduced machining cost when compared to steel. One

disadvantage of aluminium is that the steel die will make an imprint on the fixture if

the operator lowers the head without placing a part on the fixture. In this case, the

fixture must be reworked to properly support the part.

Steel Fixtures offer the best results in quality stamping and provide protection

against damage due to accidental operation of the press. Steel fixtures can be silver

soldered or welded and hand filed to match the contour of the part. All fixtures must

match the contour of the part and support the stamping area. Proper selection and

use of fixtures will reduce downtime and rejects, resulting in increased production.

Make-Ready is the term used to ensure that the product to be stamped and the

stamping die are exactly in contact to ensure a perfect result. To help correct these

irregularities, various materials such as cardboard, rubber or a mixture of cork and

rubber supplied in sheet form are available. In the graphic arts area, where an

embossed or raised effect is required, specialty products such as pour-a-counter are

available. See page 32.

32.

32

Milford Astor

Make-Ready Materials and General Supplies

Milford Astor has developed a comprehensive range of made-ready materials. These

have been selected to enable the user to achieve a high consistency in quality print

performance with increased productivity. The following information details each

product and its uses.

Black Printing Underlay

This product is used extensively throughout the foiling industry for flat stamping,

suitable for most platen presses. Quite resilient and yet soft enough to compensate

for minor variations. Supplied in sheets.

Die Mounting Tape

A heat activated tape for adhering dies to the press. Also used for adhering foam

support on cylinder presses. Currently stocked in: 38mm x 50m (1.5” x 150'), 310mm

x 50m (12” x 150'), 75mm x 50m (3” x 150').

Epoxy Glassboard

For flat stamping and foil embossing. Extremely strong and durable make-ready base

providing very clean and sharp prints. Can be used with other make-readies, such as

Coverboard and Pragotherm. Epoxy Glassboard is very flat giving correct pressure

across the make-ready.

Recommended for all type of work from fine detail to solid areas and can be used on

both Platen and Cylinder presses.

Epoxy Glass is very resilient and the fact that it is extremely difficult to dent makes it

ideal for very long production runs so reducing make-ready times. Epoxy Glass has

also been designed for repeated use on different jobs without any detrimental effect

on quality. Main advantages, very strong, even thickness across the board, cost

effective, availability. Available in: 914mm x 1220mm, 25mm x 55m, 100mm x 55m,

.5mm (.020”), .8mm (.031”), 1.0mm (.040”), 1.6mm (.062”), 2.4mm (.093”).

Pertoid

For flat stamping and flat embossing. When flat stamping, is extremely good for fine

detail printing, giving crisp, clean prints. Pertoid is recommended for Geitz and

Bobsts presses. It is extremely durable, allowing longer press runs without stopping.

Designed for repeated use. Currently stocked in 610mm x 610mm.

Polyurethane Sheets

For flat stamping. It is recommended for use as a unique make-ready board for flat

stamping large, solid areas. Despite its flexibility, it is hard enough to resist

indentation on large stampings. Its soft cushioning effect prevents bruising, even on

thin, foil edged paper labels. It can be used repeatedly, by simply replacing the

33

Milford Astor

polyurethane tape with which it is adhered to the platen. It springs back to its original

shape after stamping. Acts as a self levelling board, therefore minimising spot make-

ready. Suitable for Geitz and other large platen presses. Limitations: needs special

tape to adhere to machine bed. Not for use when doing fine detail work. Not for use on

Heidelberg presses. Currently stocked in 610mm x 610mm sheets.

Pour-A-Counter Liquid and Powder

For combination foiling and embossing. This is a two part mix system for making a

counter for the female embossing die. Shelf life of the product is 24 - 30 months.

Benefits to the Printer: Pour-a-Counter is very durable and good for use with deep

sculptured dies. Limitations: can be slightly messy.

Presspahn

Foil flat stamping. A good standard make-ready base board with a smooth surface.

Excellent for short to medium runs. Currently stocked in 1000mm x 1067mm.

Printing Base Self Adhesive

This product is used extensively throughout the foiling industry for flat stamping,

suitable for most platen presses. Quite resilient and yet soft enough to compensate for

minor variations and has the convenience of pressure sensitive application. Supplied

in sheets 690mm x 1020mm.

Yellow Cover Board

Used for blind embossing. It provides a quick, clean and very effective method for

forming a male counter for blind embossing. It can also be used on top of a Liquid and

Powder formed counter to give extra depth and aid in smoothing out stock. The board is

fixed to the machine bed and moistened with a damp cloth, or spray. A few impressions

are made and the coverboard conforms precisely to the die producing a durable blind

embossing counter. Coverboard can significantly reduce make-ready time over powder

techniques which involve prolonged drying time. Currently stocked in 61cm x 48cm

sheets.

34

Milford Astor

Tips to Save Pains and Strains

� Check the realistic registration tolerances of your printer and stamper to decrease

rejects and ensure a quality piece.

� If designing large solid areas and fine intricate areas in the same design, expect to foil

stamp it with two passes.

� Have your printer and foil stamper talk before beginning the job. COMMUNICATION

CAN SAVE EVERYONE TIME AND MONEY.

� Ink must be wax free and not rubber-based if you are foil stamping over an inked area.

� Be careful to try to avoid wet trapping your inked area by varnishing before these areas

are dry.

� Stamping over UV coatings on some applications can present a challenge. Therefore,

try to use an aqueous coating or wax free varnish whenever possible, or stamp prior to

UV coating. If you must stamp over UV varnish ask Milford Astor to advise the

appropriate UV varnish.

� Check with your printer to help determine the dyne count (surface tension) of a

laminated sheet. The dyne count should be higher than 40 for the sheet to be foil

stamped.

� Keep within your customer's budget. Foil is a very economical addition when planned

correctly. You may be able to save an entire run through the press with one slight

adjustment of your design.

� Call Milford Astor to check if the foil shade you have chosen is available in the correct

grade for your stock you are using and the coverage you are trying to achieve.

� Many pigment and pearl foils are translucent. This can drastically change the

appearance on coloured stocks. Check the opacity of your chosen foil before

specifying.

� When stamping dry, textured stocks, be sure to specify the correct foil to prevent

dulling.

� When designing foil for letterheads to be used through laser printers, it is essential to

have your customers test a stamped sample through their laser printer before running

the entire job.

� For a quality stamp of areas designed with intricate detail, be sure the space between

the lines in the design is no less than half the thickness of the stock you are using.

�

� As a general rule with hard plastics, it takes one tonne per 25mm x 25mm of stamped

area. Choice of stock, die construction and make-ready can decrease tonnage

needed. Check with your stamper for his equipment capabilities regarding your

particular design.

35

Milford Astor

Weights and Measurements of Master Rolls

Approximate weights and measurements (diameter) of Master Rolls 61cm (24”) wide on standard 25mm

(1”) diameter cores on 12 micron polyester.

Length Diameter Weight

The printing temperature range of Milford Astor Foilmakers foils is approx 100 - 170

degrees C. It is not possible to recommend a given temperature for any particular

surface to be stamped because of the varying production conditions that are

encountered. The controlling factors are as follows:

Characteristics of the foil.

Type of machine in use (hand, mechanical or air-operated and whether

semi or fully automatic).

Action of machine - time in contact with blocking surface, i.e., dwell.

Surface to be blocked - receptive or non receptive.

Type of die to be used and total area of print.

Heat source.

Variation between heater block and die face temperatures.

Ambient conditions.

1.

2.

3.

4.

5.

6.

7.

8.

The ideal foiling temperature for metallics is the lowest possible temperature

at which maximum coverage, adhesion and cleanliness is obtained.

Stamping Temperatures

Metallics

Golds, Silvers & Colours

Pigmented

Polyester

On 16mm CORES Polyester

metres feet mm inches kg lbs

61

122

183

305

200

400

600

1000

51

57

70

89

2 .90

1.72

2.35

3.06

2.00

3.80

5.20

6.70

61

122

183

305

200

400

600

1000

57

76

82.5

105

3

1.27

2.54

2.90

5.17

2.80

5.60

6.40

11.40

61 200 41.5 .90 2.00

2 1/4

2 3/4

3 1/ 2

2 1/4

3 1/4

4 1/4

1 5/8

36

Milford Astor

Foil Requirements Calculator - Imperial

Pull length

in inches

Roll 200

feet

Roll 400

feet

Roll 600

feet

Roll 1000

feet

5486

4800

4267

3840

10971

9600

8533

7680

16457

14400

12800

11520

27429

24000

21333

19200

3491

3200

2743

2560

6982

6400

5486

5120

10473

9600

8229

7680

17455

16000

13714

12800

2400

2133

1920

1745

1600

1477

1371

1280

4800

4267

3840

3491

3200

2954

2743

2560

7200

6400

5760

5236

4800

4431

4114

3840

12000

10667

9600

8727

8000

7385

6857

6400

1200

1129

1067

1011

960

914

873

835

2400

2259

2133

2021

1920

1829

1745

1670

3600

3388

3200

3032

2880

2743

2618

2504

6000

5647

5333

5053

4800

4571

4364

4174

800

768

738

711

686

662

640

619

1600

1536

1477

1422

1371

1324

1280

1239

2400

2304

2215

2133

2057

1986

1920

1858

4000

3840

3692

3556

3429

3310

3200

3097

600

565

533

505

1200

1129

1067

1011

1800

1694

1600

1516

3000

2824

2667

2526

480

457

436

417

960

914

873

835

1440

1371

1309

1252

2400

2286

2182

2087

400

384

369

356

800

768

738

711

1200

1152

1108

1067

2000

1920

1846

1778

343

331

320

310

300

686

662

640

619

600

1029

993

960

929

900

1714

1655

1600

1545

1500

/3 8

/1 2

/916

/5 8

/1116

/3 4

/78

/1516

1

1 /1 4

1 /1 2

1 /3 4

2

2 /1 4

2 /1 2

2 /3 4

3

3 /14

3 /1 2

3 /3 4

4

4 /1 4

4 /12

4 /3 4

5

5 /1 4

5 /1 2

5 /3 4

6

6 /14

6 /12

6 /3 4

7

7 /1 4

7 /1 2

7 /3 4

8

Foil Requirements Calculator - Metric

Pull length

in mmRoll 61m Roll 122m Roll 183m Roll 305m

10

12

14

16

18

20

6100

5083

4357

3813

3389

3050

12200

10167

8714

7625

6778

6100

18300

15250

13071

11438

10167

9150

30500

25417

21786

19063

16944

15250

25

30

35

40

45

50

2440

2033

1743

1525

1356

1220

4880

4067

3486

3050

2711

2440

7320

6100

5229

4575

4067

3660

12200

10167

8714

7625

6778

6100

55

60

65

70

75

1109

1017

938

871

813

2218

2033

1877

1743

1624

3327

3050

2815

2614

2440

5545

5083

4692

4357

4067

80

85

90

95

100

763

718

678

642

610

1525

1435

1356

1284

1220

2288

2153

2033

1926

1830

3813

3588

3389

3211

3050

110

120

130

140

150

555

508

469

436

407

1109

1017

938

871

813

1664

1525

1408

1307

1220

2773

2542

2346

2179

2033

160

170

180

190

200

381

359

339

321

305

763

718

678

641

610

1144

1076

1017

963

915

1906

1794

1694

1605

1525

210

220

230

240

250

290

277

265

254

244

581

555

530

508

488

871

832

796

763

732

1452

1386

1326

1271

1220

/1 81

/3 81

/5 81

/7 81

/1 82

/3 82

/5 82

/782

/1 83

/3 83

/5 83

/783

37

Milford Astor

Widths

mm

Widths

mm

Widths

mmInches Inches Inches

No.

cuts

No.

cuts

No.

cuts

Offcut Offcut Offcut

mm mm mminches inches inches

10

11

13

16

17

19

21

22

25

54

57

60

64

67

70

73

76

79

114

121

133

140

146

152

159

165

171

27

29

32

35

38

41

44

48

51

83

86

89

92

95

98

102

102

108

189

184

191

22

21

19

17

16

14

13

12

12

7

7

6

6

6

6

6

5

5

3

3

3

64

54

48

38

34

28

29

27

24

11

10

10

9

9

8

8

8

7

5

4

4

4

4

4

3

3

3

0.00

0.38

0.00

0.25

0.38

0.00

0.44

0.38

0.00

0.63

1.50

1.25

1.50

0.38

2.00

1.00

0.00

2.13

0.25

4.00

3.00

2.00

1.00

0.00

5.25

4.50

3.75

0.63

0.38

0.25

0.63

0.00

1.25

1.25

1.50

0.00

26.0

0

0.38

3.00

2.25

1.50

0.75

0.00

2.751.50

3.00

2.25

1.50

0

10

0

6

10

0

11

10

0

16

38

6

38

10

51

25

0

54

7

102

76

51

25

0

133

114

95

16

10

6

16

0

32

32

38

0

32

10

76

57

38

19

0

7

38

76

57

38

0.38

0.43

0.51

0.63

0.67

0.75

0.83

0.87

0.98

2.13

2.24

2.36

2.52

2.64

2.76

2.87

2.99

3.11

4.49

4.76

5.24

5.51

5.75

5.98

6.26

6.50

6.75

1.06

1.14

1.26

1.38

1.50

1.61

1.73

1.89

2.01

3.27

3.39

3.50

3.62

3.74

3.86

4.02

4.02

4.25

7.01

7.24

7.52

197

203

3

3

3.00

0.00

76

0

7.76

7.99

Table of cuts (from a 610mm wide roll)

Common Problems and Solutions

Reduce temperature and dwell.

SolutionProblem

Insufficient heat or dwell

1.

Reduce heat or dwell.

Bridging

2. Bad coverage

3. Foil carrier sticks to product being

stamped

4. Foil pre-heated by die or platen

5. Static electricity

6. Foil rainbows

7. Blushing on polystyrene

8. Tipping raised letter or surfaces in

plastics

9. Lines appear on printed product

Position foil guide bars in feed side down just above the

stamping surface and outfeed a little higher. This gives a

peeling action rather than a snatch. Use foil with a softer

release. Reduce temperature and / or dwell.

This causes bridging. Set foil by die guide bars so that foil is

not touching heated area.

On high speed machines this can cause foil feeding problems.

It can sometimes be reduced by placing a copper strip from

foil bars to earth.

This is caused by excessive pressure. Increase temperature

and /or dwell and reduce pressure.

Silicone rubber bonded to aluminium. In plastics higher

than normal temperature should be used as rubber is not a

good conductor of heat.

Check to ensure foil is not creased. Reduce foil tension on foil

off-take roll. On cylindrical machines, use sponge rubber.

.

38

Milford Astor

Glossary of Hot Stamping Terms

Air Press: A pneumatic cylinder applies the force.

Brass Die: A stamping die made from brass. Better and longer-lasting than

mag die (q.v.), but more expensive.

Blushing: See 'Clouding'

Bridging: See 'Filming'

Carrier: The film or paper on which foil is carried in roll leaf hot stamping.

Clouding: A milky or cloudy appearance of stamped areas. Sometimes

called blushing.

Copper Die: A stamping die etched in copper, very hard, good for long runs in

graphics.

Cork Rubber: An adhesive-backed cork sheet used as make-ready.

Detail Foil: Foil best suited for stamping fine detail, such as small lettering.

Dwell Time: Length of time the heated die is allowed to remain in contact with

the piece being stamped.

Fibre Board: Stiff paper board used as make-ready.

Filming: Excess particles of leaf around the edge of a stamped area. Also

called bridging or flooding.

First-Surface Impressions:

The stamping of foil on the top surface of a plastic part. See

'Second Surface Impression'.

Flooding: See 'Filming'.

Gassing: Caused by heated inks when stamping large areas, causing pin

holes in foil, as well as entrapment of air.

Blocking : Another word used to describe ‘Stamping’.

Cold Foil: A stamping foil that gives a similar result as hot stamping foil but

the foil does not incorporate an adhesive coat. The foil is laid

down onto a special adhesive, before UV curing and peeling off.

Corona Treatment: A method of changing the surface molecular tension of plastic

films to accept inks and varnishes.

Flashing: See ‘Filming’.

39

Milford Astor

nGlassine: A brittle, high-finish fibrous paper sometimes used as a carrier for a

imitation gold foil.

Hand Press: Pressure applied by hand to a mechanical lever.

Imitation Leaf: The dull golds and silvers made by dusting metal powders. Also

known as 'bronze powder', 'dusted leaf'.

Overprintable: A stamping foil once applied which allows over printing with ink.

Foil: The coating which is transferred from the carrier to the hot-stamped

item by a heated die. Sometimes also called 'roll leaf'. The term

derives from the original gold leaf, which was beaten into thin sheets

(leaves) by hand. Actually, leaf today is a coating or dispersion that is

applied to a carrier film.

Mag. Die: A stamping die etched in magnesium. Usually inexpensive but does

not wear well. Suitable only for relatively short runs on hard plastics

and longer runs on plasterboard.

Make-Ready: Material placed beneath the object to be stamped, usually to help in

correcting irregularities in either the piece itself or the stamping die.

Serves also as a counter for dies that are raised or embossed.

Moulded Silicone Dies:

A die moulded from silicone rubber. Used mostly for stamping

plastic objects of unusual design or material.

Oil Resistance: The ability of a stamped impression to withstand attack from any

aliphatic and most aromatic-based liquids, i.e., motor oil, benzene,

naphthalene, toluene, etc.

Opaque: A foil that permits no light to pass through the stamped impression.

Overstamp: A second stamping sometimes applied when the first is slightly

faulty.

Panel Foil: Foil that is best suited for stamping broad areas.

Picking: The effect of missing pieces of leaf from a stamped area.

Pigment Foil: Solid-colour roll foil made with organic and inorganic pigment.

Plated Foil: See 'Simulated Foil'.

Polyester: A strong, stable plastic film used as a carrier for foil.

Printability: a) The ability of a foil to be overprinted with ink,

b) As well as the ability of foil to over-stamp an ink surface.

Rainbowing: An iridescent effect in a stamped area. Usually caused by too much

heat in stamping metallic foils.

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Milford Astor

Rotary Press: The die is round, and foil is applied as the die rotates, or a flat die

and foil are applied by a rotating pressure roll which forces the

paper onto a heated die.

Second-Surface Impression:

The stamping of foil on the underside of a transparent part so that

lthe co our of the leaf shows through. Used as distinct from 'First-

Surface Impression'.

Silicone Rubber: A sheet of silicone rubber backed with steel or aluminium and

used as a hot-stamping die for raised and flat surfaces on plastics.

Made with various thicknesses of both face and backing. See

'Tipping'.

Simulated Foils: Foil of bright gold, silver and metallic colours manufactured by the

vacuum plating process.

Solids: Large or broad areas.

Stamping Press: Clamshell: A press that stamps foil with clamshell type of action,

ie. a Kluge, Thompson Heidelberg, etc.

Cylinder: A press which uses a flat die passing under an

impression cylinder.

Roll-On: A press that applies foil with a rolling action.

Rotary: A press where the die is round.

Vertical: A press that stamps with a straight up and down stroke.

Tipping: To hot stamp a raised plastic surface with silicone rubber.

Toggle Press: A pneumatic cylinder applies the force, which is multiplied by

toggle mechanism.

Top Rub: The resistance of a foil to sustained rubbing. Foil with poor top rub

will smear or break down rather easily.

Translucent: Foil stamping that allows a partial passage of light. Sometimes

used to colour a transparent plastic.

Woodgrain Foil: Foil with a woodgrain pattern.