j. michael rivera - k laser · j. michael rivera vice president of ... troubleshooting guide 36...
TRANSCRIPT
The information contained in th is handbook i s a compilation of data collected in more than six years of research and development. To ensure success with cold foil printing, we strongly suggest that you follow the recommended guidelines and avoid any shortcuts. We currently have a 10" wide, four-color UV flexographic press at our training facility that is available for job proofing, training, and seminars. We urge you to use our facility to familiarize yourself with the cold foil printing process. We at A m a g i c a n d B e a c o n Adhesives want to help you succeed!
J. Michael Rivera Vice President of Sales
IC COLDOIL
Introduction 1
Why Use Cold Foil Printing? 1
To Whom Do I Sell? 3
Cold Foil Printing Offers Many Opportunities 4
How Does Cold Foil Printing Work? 6
Types of Cold Foil Printing 7
Equipment Required 8
What Process Should I Use? 8
Dry Lamination (Conventional)
Press Set-Up 10
Suggested Web Paths 11
Process Guidelines 15
Foils 21
Troubleshooting Guide 22
Wet Lamination (Cure Thru)
Press Set-Up 24
Suggested Web Paths 26
Process Guidelines 31
Foils 35
Troubleshooting Guide 36
Afterword 37
Any part of this handbook cannot be reproduced without the written consent of Beacon Adhesives
TABLE OF CONTENTS
AUTHOR
Amagic Holographics,INC.
A member of K Laser Group
Throughout history, foil has been used to decorate many important as-pects of our lives. It was used on temples, palaces and, most impor-tantly, in manuscripts. Pure gold was the primary source of foil. It signi-fied prosperity and splendor. After the painstak-ing task of pounding gold into thin layers, the foil was then formed onto armors, caskets, statues and shields. It was also used on important docu-ments as a seal or certification.
Today, gold foil is still being used extensively as it was long ago. Foil is a valuable tool used to en-hance illustrations, packaging, and labels. Look through today’s aisles and you will see that the most noticeable products are imprinted with foil.
TIPS:
FOIL INTENSIFIES THE PRINTED IMAGE. FOIL SIGNIFIES PROSPERITY AND SPLENDOR. FOIL PRINTING HAS A HIGH PERCEIVED VALUE.
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INTRODUCTION
WHY USE COLD FOIL PRINTING?
TYPICAL FOIL CONSTRUCTION The majority of foil used today is not pure gold, but is a construction of thin film, release coating, lacquer, aluminum, and adhesive as illustrated below. Although the basic construction is the same, each foil manufac-turer has their own proprietary manufacturing techniques and compo-nents. Therefore, each brand of foil has its own strengths and weak-nesses.
TIPS:
ALTHOUGH THE BASIC CONSTRUCTION IS THE SAME, EACH FOIL MANUFACTURER HAS THEIR OWN PROPRIETARY MANUFACTURING TECHNIQUES AND COMPONENTS. THEREFORE, EACH BRAND OF FOIL HAS ITS OWN STRENGTHS AND WEAKNESSES.
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COLD FOIL
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ROTARY HOT STAMP Foil is widely used today on a rotary hot stamp system. It provides fine edg-ing and a smooth foiled image. This system is used in-line on a web press that utilizes an engraved cylinder in which the image is heated either electrically or through heated oil. Narrow web presses typically incorporate an electric system while wide web presses employ an oil-heated unit. The heat causes the foil to transfer onto the substrate. The width of the job and the amount of coverage af-fects the maximum running speed. Rotary hot stamping involves a high cost of initial investment and, since it uses an engraved cylinder, is inflexible to design changes and impractical for job testing. Also, the high cost of the engraved cylinder makes it inefficient for short runs.
PLATEN HOT STAMP The second most common use of metallized foil is with a platen hot stamp system. This system is mostly used off-line where foil is required on a pre-printed substrate. It is widely used in the offset printing industry and in the manufacture of special occasion ribbons. This process utilizes interchange-able flat plates which are heated electrically. The heated plate then de-scends and applies pressure onto the substrate. The substrate is either hand fed or webbed through the machine. A platen hot stamp system is quite economical, but runs at a very slow speed. Due to its slow speed, in-stallation for an in-line process can be complicated. The types of graphics are usually limited to text and bold images. Since this process is time con-suming, it’s suitable only for very short runs. METALLIZED SUBSTRATES For years, metallized substrates have been widely used in the gravure printing of gift wrapping papers. This application is now gaining acceptance in the packaging industry. Typically, the printer will print on top of the metallized substrate to cover the areas that do not require a foiled image. Although metallized substrates accept water-based, solvent-based, and UV-curable inks, there are still some issues regarding adhesion and foil in-tegrity in the blister packing industry. Since overprinting is re-quired, this application is quite limited. Metallized substrates can be purchased in sheet or web form but the additional expense sub-stantially increases the final cost of the job.
WHY USE COLD FOIL PRINTING?
TIPS:
ALTHOUGH THE BASIC CONSTRUCTION IS THE SAME, EACH FOIL BRAND HAS ITS OWN STRENGHTS AND WEAKNESSES. THE HIGH COST OF AN ENGRAVED CYLINDER MAKES ROTARY HOT STAMPING INEFFICEINT FOR SHORT RUNS. A PLATEN HOT STAMP SYSTEM IS QUITE ECONOMICAL, BUT RUNS AT VERY SLOW SPEEDS. METALLIZED SUBSTRATES CAN SUBSTANTIALLY INCREASE THE COST PER LABEL.
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COMPETITION Cold foil printing was never designed to entirely replace the hot stamp sys-tem, although cold foil printing allows for greater flexibility and lower oper-ating cost. Rather than competing against hot stamping, cold foil printing allows the printer to expand his foil market.
CANDIDATES Typically, any product requiring a high level of shelf appeal is a good candi-date for cold foil printing. Household consumables, cigarette cartons, wine labels, and cosmetic packaging are usually the heavy hitters. With the ad-vent of holographic, diffractive and refractive foils, foil has broadened its use to include packaging and board applications. While rotary hot stamp dominates the long run market and platen hot stamp has the very short run market, cold foil printing can prevail over the “medium run” market. A “medium run” can be defined as a foil application in which the size of the job cannot justify the cost of an engraved cylinder and would be too time consuming to run on a platen hot stamp system. Cold foil printing is a perfect fit for low cost jobs such as children’s stickers and gift tags. Jobs that were printed with gold or metallized ink also fall into this category. These jobs have a tendency to appear as a matte color and do not have the brilliance of foil.
Process Comparison
Process Maximum Speed
Initial Cost
Job Cost
Graphics Design Changes
Ideal Run
Cold Foil Printing
700 fpm None Low (photo polymer
plates)
Half tone to full flood
Flexible Long and Short Runs
Rotary Hot Stamp
150 fpm High High (engraved die)
Limited to Text and Bold
Images
Inflexible Long Runs
Platen Hot Stamp
120 cycles/min Medium Low (plates)
Limited to Text and Bold Im-
ages
Flexible Short Runs
Metallized Substrates
700 fpm None High (substrate)
Limited to Trapping
Flexible Long Runs
TO WHOM DO I SELL?
TIPS:
COLD FOIL PRINTING CAN PREVAIL OVER THE “MEDIUM RUN” MARKET. TYPICALLY, ANY PRODUCT REQUIRING A HIGH SHELF APPEAL IS A GOOD CANDIDATE FOR COLD FOIL PRINTING. COLD FOIL PRINTING IS A PERFECT FIT FOR LOW COST JOBS.
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Cold foil printing is suitable for the packaging industry. Large printed areas with a small foil image, printed logos over a square, oval, or a special shape foiled image, and security strips for DVD and CD covers are but a few applica-tions for this industry. Although these are long run jobs, a printer can expect substantial savings with cold foil printing.
An exciting new application is also available with cold foil printing. In the past, halftone metallic effects were impossible with the use of foils. Now such ef-fects can easily be achieved with cold foil printing and open many different options in the design of labels and packaging. The end-users must be made aware of this new application which can give a printer the competitive edge.
Cold Foil Market Industry Type of Job
Cosmetic Labels for lipstick, make-up, nail polish, sample products,
Food & Drug Shampoo labels, toothpaste boxes
Wine Labels for local wineries
Pharmaceutical Label for nutritional supplements
Beverage Labels for local beverage companies
Consumer New products geared for market testing
Packaging Security strips, holograms on blister packs
Miscellaneous Children’s stickers, gift tags
TO WHOM DO I SELL?
TIPS:
COLD FOIL PRINTING CAN ALSO BE ACCOMPLISHED WITH A ROTARY LETTER-PRESS OR WEB OFFSET PRESS.
COLD FOIL PRINTING OFFERS MANY OPPORTUNITIES! Below is a list of other opportunities possible with cold foil printing: ♦ Traditional hot stamp jobs, particularly the type that has multiple sizes
and are short run. ♦ Security strips, such as CD or DVD, concert and sport tickets. ♦ Product identification system (random image). ♦ Pattern flood with overprint images using opaque or transparent inks. ♦ In-house converting of holographic substrate. ♦ Opaque pigmented foils or preprinted image (without metal). ♦ Cold Foil Printing can also be accomplished with a rotary letterpress or
web offset press. ♦ Combination embossing and foil transfer without the use of heat. ♦ Can be used with a foil saver system. ♦ Ideal for wide web applications.
TIPS:
COLD FOIL IS SUITABLE FOR THE PACKAGING INDUSTRY...ALTHOUGH THESE ARE LONG RUNS, A PRINTER CAN EXPECT SUBSTANTIAL SAVINGS WITH COLD FOIL PRINTING. AN EXCITING NEW APPLICATION IS ALSO AVAILABLE WITH COLD FOIL PRINTING...HALFTONE METALLIC EFFECTS.
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COLD FOIL PRINTING OFFERS MANY OPPORTUNITIES
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Below are some examples of cold foil opportunities:
Dietary Supplements, ideal for multiple label size
Traditional Wine Labels, ideal due to short run requirements
Return labels for special occa-sions and non-profit organizations
Holographic random
image for product identification
Small Price Tags
In-house converting
of holographic substrates for bumper
sticker, license plates, and high-end packaging
Holographic image for anti-
counterfeit applications
Labels for the health and beauty aids, cosmetics and shampoo products.
Transfer opaque white for single bump printing.
Toothbrush Packaging
NOT JUST FOR FLEXO PRINTING! The idea behind cold foil printing is quite simple: using a standard print-ing plate, an image is printed onto a substrate with the use of a UV-curable cold foil adhesive. A UV dryer then activates the adhesive. The extracted foil is affixed to the printed adhesive and an image is created. There are two types of processes of cold foil printing available - wet or dry lamination. Each process uses a specially formulated adhesive that is not inter-changeable with the other. It is important that each application is care-fully reviewed to determine which one is best suited for the printer’s needs. Although the following process was originally designed for use on a flex-ographic press. Further tests have proven suitability on other printing processes such as rotary letterpress, web offset printing and screen printing. It is important to remember that positive control of the sub-strate is required to ensure success.
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HOW DOES COLD FOIL PRINTING WORK?
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Future Applications of Cold Foil Printing
Type of Printing Process
Web Offset
Sheet-Fed Off-Line Cold Foil Printing Machine
Web-Fed Off-Line Cold Foil Printing Machines
Cold Foil Printing with Foil Saver Option
Converting Machines For Converting of Holographic Substrates
Specialty Machine for the Transfer of Pre-Printed Images
Magnetic Strip Applications
Lamination of Opaque Substrates
TIPS:
EACH PROCESS USES A SPECIALLY FORMULATED ADHESIVE THAT IS NOT INTERCHANGEABLE WITH THE OTHER. IT IS IMPOR-TANT THAT EACH APPLICATION IS CAREFULLY REVIEWED TO DETERMINE WHICH ONE IS BEST SUITED FOR THE PRINTER’S NEEDS.
IS CURRENTLY WORKING WITH VARIOUS MACHINE MANUFACTURERS FOR POSSIBLE APPLICATION OF OFF-LINE COLD FOIL PRINTING, SHEET-FED OFFSET AND THE WIDE WEB FLEXO PRINTING INDUSTRIES.
K LASERTECHNOLOGY INC.
K LASER TECHNOLOGY INC. is curently working with various machi-ne manufacturers for possible applicationof off-line cold foil printing,sheet-fed offset and the wide web flexo printing industries.
DRY LAMINATION (CONVENTIONAL) For dry lamination, Beacon’s cationic adhesive, Magna-Cryl 4503, 4505 and 4520 can be used. Using a standard printing plate, an image is printed onto a substrate from a standard print station. The UV dryer acti-vates the adhesive which makes the adhesive tacky. The foil is then nipped onto the substrate with a nip roll or a spare anvil in a die station, and then is immediately pulled away to the waste wind-up. The extracted foil is af-fixed to the printed adhesive and an image is created.
WET LAMINATION (CURE TRU) For wet lamination, Beacon’s free radical adhesive, Magna-Cry 4520 can be used. Using a standard printing plate, an image is printed onto a sub-strate from a standard print station. The foil is then laminated onto the sub-strate, which is then passed under a UV lamp station. The printed adhesive is cured thru the foil, bonding the foil onto the substrate. The foil is then stripped and wound to a waste wind-up.
TYPES OF COLD FOIL PRINTING
TIPS: FOR DRY LAMINATION, BEACON’S CATIONIC ADHESIVES, MAGNA-CRYL 4505, 4503 OR 4512 CAN BE USED. FOR WET LAMINATION, BEACON’S FREE RADICAL ADHESIVE, MAGNA-CRYL 4520 CAN BE USED. A STANDARD PRINTING PLATE CAN BE USED FOR PRINTING THE COLD FOIL ADHESIVE. BEACON’S COLD FOIL ADHESIVES HAVE BEEN SPECIALLY FORMULATED TO CURE WITH A STANDARD 400 WATT UV DRYER.
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Printed image
UV light
foil
Wet Tacky Hard
Printed image
UV dryer
foil
Wet Hard
Cold foil printing has allowed many printers to enter a new market with minimal investment. The following industry standard equipment is required:
□ standard print station
□ die station or a high pressure nip station for dry lamination/laminating station for wet lamination
□ UV dryer with variable output control
□ laminating arm and waste wind-up
□ Standard printing plate mounted on a print cylinder
□ 80 durometer (or higher) nip roll or a spare anvil
EQUIPMENT REQUIRED
TIPS: AS WITH ANY PROCESS, THE INDUSTRY IS ALWAYS LOOKING FOR THAT “ONE” COLD FOIL PROCESS THAT CAN ACCOMPLISH EVERYTHING. WE HIGHLY RECOMMEND THAT YOU FAMILIARIZE YOURSELF WITH BOTH THE WET AND DRY LAMINATION PROCESS
WHAT PROCESS SHOULD I USE? THE BIG QUESTION! As with any process, the industry is always looking for that “ONE” cold foil process that can accomplish everything. In the past, while printers have been successful with cold foil printing, many have had difficulties in re-creating their success on their second job. Remember, each process has it’s own advantages, it also has it’s own individual limitation. Using just “ONE” process has resulted in many “Hit or Miss” results.
We highly recommend that you familiarize yourself with both the wet and dry lamination process and their advantages and limitations. This will enable you to decide which process is more suitable based on the type of your printed job.
TIPS: COLD FOIL PRINTING HAS ALLOWED MANY PRINTERS TO ENTER A NEW MARKET WITH MINIMAL INVESTMENT.
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Type of Job Wet Lamination Dry Lamination
Cold Foil on Top of Water-Based Inks
Compatible Not Compatible
Cold Foil on Top of UV-Curable Inks
Compatible Compatible
Cold Foil in any Print Station Easy Complicated
Medium to Large Images Excellent Poor
Small Amount of Images Poor Excellent
Small Open Circles Poor Excellent
Fine Line Reverse Poor Excellent
Paper Substrates Medium Excellent
Film Substrate Excellent Excellent
Easy to Operate Yes Medium
Post Cure None 24 Hours
TIPS: RELOCATION OF THE UV DRYER TO A HORIZONTAL POSITION IS MANDATORY TO ENSURE SUCCESS. THE UV DRYER MUST BE INSTALLED AS CLOSE AS POSSIBLE TO THE DIE OR NIP STATION. CAM AND AIR ACTUATED NIPS USUALLY CANNOT PROVIDE THE SUFFICIENT AMOUNT OF PRESSURE NEEDED FOR GOOD FOIL TRANSFER. THE PRINTED SIDE OF THE SUBSTRATE CANNOT MAKE CONTACT WITH ANY IDLER ROLLS. APPLYING MORE ADHESIVE WILL ONLY INCREASE DOT GAIN AND CREATE A BUMPY IMAGE
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DRY LAMINATION (CONVENTIONAL) PRESS SET-UP
[1] It is important that a die station is located immedi-ately after the print station that will be printing the adhe-sive. The nip process requires high pressure. Cam and air actuated nips usually cannot provide the sufficient amount of pressure needed, resulting in pinholes and rough edges. Since all flexographic presses have multiple die stations, it is best to use the first die station immediately after the print station.
[2] Re-web the press so that the substrate enters the first die station immediately after the print station. The printed side of the substrate cannot make contact with any idler rolls between the impression cylinder and the
first die station. This will smear the printed image.
[3] Relocate the UV dryer between the print station and the first die sta-tion. UV dryers are typically installed in a vertical position right after the hot air dryers. Relocation to a horizontal position is mandatory to ensure success. Once the UV dryer has been relocated, it can be used in that same position for UV printing and coating.
[4] For ease of operation, the laminating arm and waste wind-up must be located within the immediate vicinity of the first die station.
Ideal set-up, with the right
amount of adhe-sive for the job
When less adhesive is required for the job, the adhesive will cure faster resulting in a bad foiled image. Applying more adhesive will only in-
crease dot gain and create a bumpy image.
Nip Location:
Printed image
UV light
foil
Wet Tacky Hard
Printed image
UV light
foil
Wet Tacky Hard
DRY LAMINATION (CONVENTIONAL)
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The ideal solution is to locate the nip point immediately after the UV dryer. This will enable the printer to perform a wide variety of print jobs.
Most “Hit and Miss” results are caused by this problem.
Move nip point close to the UV
CHOOSING THE RIGHT NIP: Choosing the correct type of nip station is very critical. It must the incorpo-rate the following features: ♦ Aluminum or hardened steel Base Roll. Hardened steel is preferred for
easy clean up. ♦ It is recommended that the Base Roll is driven with the press especially
with presses that runs at low web tension. Since a high degree of pres-sure is required for full foil transfer, this can cause a drag on the web re-sulting in poor registration. A driven Base Roll will help maintain web ten-sion.
♦ An 80 durometer (or higher) nip roll or a spare anvil can be used to lami-nate the foil onto the substrate. A low durometer nip roll will cause pin-holes. When using a nip roll, try to get the highest durometer possible. A gear driven nip or a spare anvil is preferred to ensure that the foil will travel the same speed as the substrate.
♦ It is important that the foil comes in contact with the substrate at the nip point to prevent air entrapment. This can result in a faded foil image. Make sure that the nip roll or spare anvil and the bottom anvil are com-pletely clean. Any contamination will transfer to the foil image.
♦ A non-heated engraved cylinder can be used to transfer the foil and to
emboss the image at the same time. The engraved cylinder MUST not have a recess at the inside part of the image.
Foil
Substrate
Foil
Substrate
Foil
Substrate
INCORRECT CO R RE C T
TIPS:
THE IDEAL SOLUTION IS TO LOCATE THE NIP POINT IMMEDIATELY AFTER THE UV DRYER. THIS WILL ENABLE THE PRINTER TO PERFORM A WIDE VARIETY OF PRINT JOBS. MOST “HIT AND MISS” RESULTS ARE CAUSED BY THIS PROBLEM. MAKE SURE THAT THE NIP ROLL OR SPARE ANVIL AND THE BOTTOM ANVIL ARE COMPLETELY CLEAN. ANY CONTAMINATION WILL TRANSFER TO THE FOIL IMAGE. IT IS IMPORTANT THAT THE FOIL COMES IN CONTACT WITH THE SUBSTRATE AT THE NIP POINT TO PREVENT AIR ENTRAPMENT.
Printed image
UV light
foil
Wet Tacky Hard
ALLIED GEAR
SUGGESTED WEB PATH All of the flexographic and rotary letterpress manufacturers now offer a cold foil option for new press purchases. For existing flexo presses, please refer to the recommended web paths below.
DRY LAMINATION (CONVENTIONAL)
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Print Station UV Dryer
Foil Unwind
Foil Rewind
Die Station
For Allied Gear Flexomaster 3, Flexomaster 4, 300 and 500 Series, the UV dryer must be relocated into a horizontal position. Position the UV dryer as close as possible to the first die station. For 500 Series presses, bypass the middle nip assembly prior to the first die station.
Press Set-Up on an Allied 300 Series Press
AQUAFLEX/CHROMAS For Aquaflex LC, DBX, BX, LX, Instraprep and Instaflex, the UV dryer must be relo-cated in a horizontal position. The middle nip station can be used as a cold foil nip station providing that the rubber nip is re-placed with a high durometer (85 durome-ter or higher) nip and a pressure bar is in-stalled on top of the nip assembly. Note
that the air cyl-inders in a standard nip assembly will not be able to apply enough pressure to at-tain a good quality of foil transfer.
Press Set-Up on an Aquaflex DBX Pressure Bar avail-able through Aquaflex
Print Station
UV Dryer
Foil Unwind Foil Rewind
DRY LAMINATION (CONVENTIONAL)
SUGGESTED WEB PATH
GIDUE
ARPECO ENGINEERING
Print Station
UV Dryer
Foil
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For Arpeco presses, a nip station must be installed after the UV dryer. This nip station is available as an option from Arpeco Engi-neering.
Press Set-Up on an Arpeco press
Press Set-Up on a Gidue press
For Gidue presses, a cold foil module can be purchased from Gidue. This cold foil module is a complete system with a UV dryer, unwind, re-wind and a nip station.
Print Station
UV Dryer
Die Module
An accessory module or a similar extension must be installed
Foil
MARK ANDY 2200
For Mark Andy 2200, an accessory or a similar extension must be installed between the last print station and the first die station. The UV dryer must be relocated in a horizontal position and must be installed as close as possible to the first die station.
DRY LAMINATION (CONVENTIONAL)
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Print Station
UV Dryer
Die Module
Foil MARK ANDY 4150 & 4200 For Mark Andy 4150 & 4200, re-
locate the UV dryer on a horizon-tal position and install the dryer as close as possible to the first die station. Due to the die station frame, the UV dryer will be posi-tioned 16” away from the first die station. This will limit the printers capability to using aniloxes with 500 line count or lower. Remember, for dry lamina-tion, a high capacity UV dryer is NOT required. Tests have shown that a small portable UV dryer can provide sufficient amount of curing and is easier to install be-tween the die frames.
For Nilpeter flexo and letterpresses, a cold foil module is avail-able through Nilpeter. This module includes an infinite variable output UV dryer, a nip assembly, a rewind and an unwind. Due to the compact design of the Nilpeter presses, this module is required to accomplish cold foil printing. Notice that this mod-ule has been designed with a longer dwell to allow the printer to use foils with tighter release properties.
Press Set-Up on a Nilpeter press
Infinite variable UV output dryer system
NILPETER
SUGGESTED WEB PATH
Print Station
UV Dryer
Foil
Die Module
ROTOPRESS 3500 & 4000
Print Station
UV Dryer Foil
Die Module
WEBTRON 1000, 1600 & 1800
DRY LAMINATION (CONVENTIONAL)
TIPS:
THE UV DRYER MUST BE INSTALLED AS CLOSE AS POSSIBLE TO THE DIE OR NIP STATION. THIS WILL ENSURE THAT THE COLD FOIL ADHESIVE IS AT ITS HIGHEST TACK LEVEL AT THE NIP POINT. FOR FLEXO AND LETTERPRESSES THAT ARE NOT LISTED, PLEASE PROVIDE A WEB PATH AND WE WILL NOTIFIY YOU OF OUR RECOMMENDATIONS.
SUGGESTED WEB PATH
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Line Speed: To attain a good cold foil image, it is important that the adhesive is cured to a point where it can provide the highest level of temporary tack. This can be achieved by varying the press speed. A low press speed can over-cure the adhesive and a high press speed can under-cure the adhesive. The cure rate can also vary depending on the color of the substrate. If the cold foil image is being over-printed on top a pre-printed ink, the color of the ink can also change the cure rate.
When performing cold foil printing on top of a white (or light colored) substrate, the UV light bounces off the substrate and cures the
adhesive twice resulting in high press speeds.
UV Light
Light Colored Substrate
Printed Adhesive
UV Light
Printed Adhesive
Clear or Dark Colored
Substrate
When performing cold foil printing on top of a clear (or dark colored) substrate, The UV light goes through the substrate, or is absorbed by the dark color, and cures
the adhesive once resulting in low press speeds.
TIPS:
ALL OF OUR COLD FOIL ADHESIVES HAVE BEEN DESIGNED TO BECOME HARD WHEN FULLY CURED. THIS PROVIDES THE PROPER ADHESION TO PASS THE STANDARD TAPE AND SCRATCH TESTS. SINCE IT IS POSSIBLE TO UNDER-CURE OR OVER-CURE THE COLD FOIL ADHESIVE, THE FOLLOWING FACTORS ARE OF GREAT IMPORTANCE: NIP LOCATION RELATIVE TO THE UV DRYER AND LINE SPEED. TO ATTAIN A GOOD COLD FOIL IMAGE, IT IS IMPORTANT THAT THE ADHESIVE IS CURED TO A POINT WHERE IT CAN PROVIDE THE HIGHEST LEVEL OF TEMPORARY TACK
PROCESS GUIDELINES: CURING DRY LAMINATION COLD FOIL ADHESIVE In the past, most printers performing cold foil printing utilized a pressure sensitive adhesive. These adhesives remained tacky and provided a foiled image which can be scratched. This required an overcoat or lamination to protect the foiled image.
All of our cold foil adhesives have been designed to become hard when fully cured which provides the proper adhesion to pass the standard tape and scratch tests. An overcoat or lamination is NOT required to protect the foiled image.
♦ Since it is possible to under-cure or over-cure the cold foil adhesive, the following factors are of great importance:
♦ Line Speed ♦ Nip Location relative to the UV dryer
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DRY LAMINATION (CONVENTIONAL)
DRY LAMINATION (CONVENTIONAL)
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TIPS:
TO ATTAIN A GOOD COLD FOIL IMAGE, IT IS IMPORTANT THAT THE ADHESIVE IS CURED TO A POINT WHERE IT CAN PROVIDE THE HIGHEST LEVEL OF TEMPORARY TACK. JUST LIKE STANDARD PRINTING, COLD FOIL PRINTING WILL REQUIRE A SKILLED OPERATOR TO CONSISTENTLY P RODUCE HIGH-QUALITY PRODUCTS AND PROFITABILITY. SINCE THE COLD FOIL ADHESIVE HAS A TENDENCY TO CURE FASTER ON HALFTONE AND FINE TYPE COMPARED TO LINE WORK AND SOLIDS, BOTH CANNOT BE RUN ON THE SAME PHOTOPOLYMER PLATE.
Printed Adhesive Dark Colored Ink
UV Light
Substrate
UV Light
Printed Adhesive Light Colored Ink
Substrate
When performing cold foil printing on top of a white (or light colored) pre-printed ink, the UV light bounces off the ink and cures the adhesive twice resulting in
high press speeds.
When performing cold foil printing on top of a black (or dark colored) pre-printed ink, The UV light is absorbed
by the dark color and cures the adhesive once resulting in low press speeds.
CHOOSING THE RIGHT JOB: Cold foil printing can be achieved with any type of job that is normally printed on a printing press. As with any new process, you must carefully review the job and consider the current capabilities of your press. Remember that cold foil printing will take up a print station and a die station. Just like standard printing, cold foil printing will require a skilled operator to consistently pro-duce high-quality products and profitability. PRINTED DESIGN: One of the exciting development in cold foil printing is the capability of print-ing screen work and halftone. But as with flexographic printing, dry lamina-tion cold foil printing has limitations regarding the types of printed design. Since the cold foil adhesive has a tendency to cure faster on halftone and fine type compared to line work and solids, both cannot be run on the same photopolymer plate.
DRY LAMINATION (CONVENTIONAL)
TIPS: EACH MAGNA-CRYL ADHESIVE HAS BEEN DESIGNED FOR A PARTICULAR SUBSTRATE FOR ADHESION AND SCRATCH RESISTANCE AND ARE NOT INTERCHANGEABLE. BEACON ADHESIVES MANUFACTURES THREE VERSIONS OF MAGNA-CRYL 4505 TO GIVE THE FLEXO-GRAPHIC PRINTER EASE OF CONTROL OVER THE PRESS SPEEDS. THE MAGNA-CRYL 4500 SERIES HAS BEEN DESIGNED TO WITHSTAND THE STANDARD TAPE AND SCRATCH RESISTANCE TESTS. WE RECOMMEND THE USE OF A DOCTOR BLADE TO MAINTAIN CONSISTENCY AND THE EVEN DISTRIBUTION OF ADHESIVE.
CHOOSING THE ADHESIVE: Select the type of cold foil adhesive depending on the type of substrate that will be printed. Note that each Magna-Cryl adhesive has been designed for a particular substrate for adhesion and scratch resistance and are NOT inter-changeable. There are three types of Magna-Cryl adhesives that are currently available; Magna-Cryl 4505 - use for paper substrates: Beacon Adhesives manufactures three versions of Magna-Cryl 4505 to give the flexographic printer ease of control over the press speed. The Magna-Cryl 4505 has a “window” in which the foil will transfer with the highest qual-ity and adhesion. Each grade can also be mixed to attain running speeds be-tween the original grades. The Magna-Cryl 4505 can be printed over free radical UV inks and coatings, but not over water or solvent based inks. Magna-Cryl 4505 can be printed next to an image printed with water or sol-vent based ink as long as trapping does not occur.
Magna-Cryl 4505S Slow Color: Red
Press Speed: 60-120 fpm Viscosity: 1200 cps
Magna-Cryl 4505M Medium Color: Blue
Press Speed: 150-250 fpm Viscosity: 900 cps
Magna-Cryl 4505F Fast Color: Green
Press Speed: 300-400 fpm Viscosity 500 cps
Magna-Cryl 4503 - use for paper or film substrates: There is only one version of Magna-Cryl 4503, which has been specially for-mulated for use with paper, polypropylene, OPP and BOPP. Magna-Cryl 4503 can be printed over free radical UV inks and coatings, but not over water or solvent based inks. It can be printed next to an image printed with water or solvent based inks as long as trapping does not occur.
Magna-Cryl 4580 - use for letterpress on paper or film substrates: There is only one version of Magna-Cryl 4580. It has been formulated for use on letterpress machines. It is a free radical adhesive and can be printed on top of water-based and UV-curable inks. Note that the Magna-Cryl 4580 may not be able to provide full adhesion to the substrate and an overcoat or lamination might be required to protect the foil image.
Magna-Cryl 4503 Color: Blue
Press Speed: 60-400 fpm Viscosity: 900 cps
Magna-Cryl 4580 Color: Blue
Press Speed: 100-350 fpm Viscosity: 1200 cps
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Other types of film substrates: We are constantly testing new adhesives for other film applications. Please contact us to get an update on new developments. For specialty and cus-tom film applications, we can perform a test run to investigate the compati-bility of the adhesive to the substrate. SPECIAL NOTATION: When using cationic UV products, formation of benzene as a by-product during photo initiation and polymerization process is possible. Small amounts have been detected during the curing process. Due to many varia-tions related to formulation and pressroom options, and exact quantifica-tion of the benzene level is difficult to confirm. OVERCOAT AND LAMINATION: The Magna-Cryl 4500 Series has been designed to withstand the standard test for scratch resistance and the standard tape test. Over-coating or lami-nation are not required to protect the printed image. CHOOSING THE RIGHT ANILOX: Start with a ceramic anilox with 300 line, 6.5 bcm. The logic line count is the same as when printing UV inks. Fine detail will require higher line count while large block areas need lower line counts. We recommend the use of a doctor blade to maintain consistency and the even distribution of adhe-sive. For uncoated paper stock, use a lower line count to compensate for absorption. For film substrate, use a higher line count. PREPARING THE PRINT STATION: The Magna-Cryl 4505 and 4503 are cationic adhesives. They are incom-patible with water and solvent based inks. If the print station was used with water or solvent based ink, it must be washed with vinegar before cold foil printing. If there is any dried ink in the anilox cells, clean with Xylene and then dry with acetone. Make sure that the solvents have sufficiently evapo-rated prior to pouring the adhesive. LAMINATING ARM AND WASTE WIND-UP: Set the tensions on both the laminating arm and waste wind-up to “low”. Maintain a low tension setting to avoid any slack on the foil. High tension will cause the foil to travel faster or slower than the substrate and will re-sult in rough edging or cracks in the image. PRINTING PLATES: Cold foil printing does not require a special printing plate. A standard print-ing plate can be used. Standard sticky-back tapes, magnetic print cylinders or trail edge mount systems can be used.
DRY LAMINATION (CONVENTIONAL)
TIPS:
START WITH A CERAMIC ANILOX WITH 300 LINE, 6.5 BCM. THE LOGIC LINE COUNT IS THE SAME AS WHEN PRINTING UV INKS...FINE DETAILS WILL REQUIRE HIGHER LINE COUNT WHILE LARGE BLOCK AREAS NEED LOWER LINE COUNTS. FOR UNCOATED PAPER STOCK, USE A LOWER LINE COUNT TO COMPENSATE FOR ABSORPTION. THE MAGNA-CRYL 4505 AND 4503 ARE CATIONIC ADHESIVES. THEY ARE INCOMPATIBLE WITH WATER AND SOLVENT BASED INKS. COLD FOIL PRINTING DOES NOT REQUIRE A SPECIAL PRINTING PLATE. A STANDARD PRINTING PLATE CAN BE USED.
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DRYER SETTINGS: Although the Magna-Cryl 4500 Series adhesives were tested with a 600 watt UV lamp in the 32nm range, most UV dryers installed on flexo presses will easily cure Magna-Cryl 4500. The UV light that cures Magna-Cryl 4500 MUST NOT vary in energy output as the press changes speed. Variations will make it difficult to find the “window” of foil transfer. If your UV dryer has an auto ramp, turn this option “OFF”. In addition to varying the running speed by mixing different grades of our Magna-Cryl 4505, you can also vary the running speed by changing your dryer setting to low, medium or high. For ex-ample: using the Magna-Cryl 4505M (medium) with a 400 watt UV dryer at “High” setting, your average running speed will be about 165 fpm. By chang-ing your dryer setting to “Medium”, you can reduce your speed to about 125 fpm, and a dryer setting of “Low” will reduce your speed to about 80 fpm. Note that these figures are estimates and can change depending on the UV lamp output, lamp life and overall condition of your UV dryer. IDLER ROLLS: It is important that the printed side of the substrate does not make any con-tact with an idler roll between the print station and the die station. When webbing the press, make sure that all idler rolls are bypassed in this area. We recommend that the idler rolls, immediately after the first die station, are coated with Teflon to prevent “picking” the image after the foil transfer. At this point, the adhesive is still tacky and will require up to 12 hours to fully cure. DIRT CONTAMINATION: Dirt contamination from the substrate is an important issue with cold foil printing. Unlike conventional ink printing, cold foil printing is not forgiving when the photopolymer plate and the substrate have been contaminated with dirt. The contamination usually stays in the plate until it is manually re-moved. Dirt contamination causes large holes in the foil image which are visible to the naked eye. It is highly recommended that a web cleaner, or other means of contamination removal, is used to prevent this problem.
DRY LAMINATION (CONVENTIONAL)
TIPS:
THE UV LIGHT THAT CURES THE MAGNA-CRYL 4500 MUST NOT VARY IN ENERGY OUTPUT AS THE PRESS CHANGES SPEED. IT IS IMPORTANT THAT THE PRINTED SIDE OF THE SUBSTRATE DOES NOT MAKE ANY CON-TACT WITH AN IDLER ROLL BETWEEN THE PRINT STATION AND THE DIE STATION. WE RECOMMEND THAT THE IDLER ROLLS, IMMEDIATELY AFTER THE FIRST DIE STATION, ARE COATED WITH TEFLON TO PREVENT “PICKING” THE FOIL IMAGE. UNLIKE CONVENTIONAL INK PRINTING, COLD FOIL PRINTING IS NOT FORGIVING WHEN THE PHOTOPOLYMER PLATE AND THE SUBSTRATE HAVE BEEN CONTAMINATED WITH DIRT.
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READY, GET SET… GO COLD!: 1) Mount the photopolymer plate onto the print
cylinder and position the print cylinder into the print station.
2) Prepare the print station using the same pro-
cedure when printing inks. Adjust the plate cyl-inder with a “check gauge” or you can do it manually.
3) Set the fountain roll and doctor blade and pour the adhesive into the ink tray. Make sure that the adhesive is metered correctly. 4) Load the foil onto the laminating arm and web as described in the Recommended Web Path. 5) Position the nip roll or the spare anvil into the first die station and apply a slight pressure. 6) Make sure that the UV dryer is “on”, the auto ramp option is “off” and the heat setting is on “LOW”.
7) Run the press at around 50 fpm and activate the
impression. Set the print cylinder fine adjustment as you would using standard procedures. The cold foil adhesive has been tinted to enable the operator to see the image.
8) Increase the nip pressure at the die station until
an image appears. Make sure that even pressure is applied to prevent the substrate from tracking. It is typical to apply a high degree of nip pressure to attain a fine edge on the image.
9) Increase the speed until the image becomes clearer and full foil transfer is achieved. 10) If the resulting speed is too low, increase the UV dryer output to
“Medium” or “High” until the desired speed is at-tained. 11)Do not perform a tape or scratch test until post cure is complete (within 12 to 24 hours).
DRY LAMINATION (CONVENTIONAL)
TIPS:
A STANDARD PHOTOPOLYMER PLATE CAN BE USED FOR PRINTING THE COLD FOIL ADHESIVE. SET THE PRINT CYLINDER FINE ADJUSTMENT AS YOU WOULD USING STANDARD PROCEDURES. INCORRECT PLATE CYLINDER ADJUSTMENT CAN RESULT IN CROWNING AROUND THE FOIL IMAGE. MAKE SURE THAT THE AUTO RAMP OPTION IN THE UV DRYER IS ‘OFF”. MAKE SURE THAT THE NIP ROLL OR SPARE ANVIL AND THE BOTTOM ANVIL ARE COMPLETELY CLEAN. ANY CONTAMINATION WILL TRANSFER TO THE FOIL IMAGE. IF RESULTING SPEED IS TOO LOW, INCREASE THE UV DRYER OUTPUT UNTIL THE DESIRED SPEED IS ATTAINED.
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DRY LAMINATION (CONVENTIONAL)
FOIL
♦ Conventional Colors (Color matching is available) ♦ Holographic ♦ Security Images. ♦ Pigmented It is mandatory to use specific foils for the cold foil printing process. A stan-dard hot foil will not transfer when using a cold foil adhesive. When choosing the right foil, remember that although the basic construction is the same, each foil manufacturer has their own proprietary manufacturing techniques and components. Therefore, each foil has its own strengths and weak-nesses. We have tested samples from all of the major manufacturers of foil and found that each one behaved differently depending on the printing job. Each foil has its own properties regarding release, porosity, adhesion, and printability. These factors must be taken into consideration when choosing the right foil for a specific job. There is no one foil construction that can be used for all types of cold foil printing. We recommended that you test the foil for each specific print job.
BASIC COLD FOIL CONSTRUCTION
ADHESION:
PRINTABILITY:
TIPS:
IT IS MANDATORY TO USE SPECIFIC FOILS FOR THE COLD FOIL PRINTING PROCESS. A STANDARD HOT FOIL WILL NOT TRANSFER WIHEN USING COLD FOIL ADHESIVE. ALTHOUGH THE BASIC CONSTRUCTION IS THE SAME, EACH FOIL BRAND HAS ITS OWN STRENGTHS AND WEAKNESSES. TO ENSURE SUCCESS, WE NOW PROVIDE OUR
OWN THIS FOIL HAS BEEN SPECIALLY FORMULATED TO WORK IN CONJUNC-TION WITH ALL OF Magna-Cryl COLD FOIL ADHESIVES.
Page 21
To ensure success. we now provide our own This foil has beenspecially formulated to perform with all of our Magna-Crtyl cold foil adhes-ives. Our will work on both dry and wet lamination process and are interchangeable.They are avaiable in:
Issues regarding printability occur when a job requires ink to be printed ontop of a foil image. Our have shown sufficient adhesion to bothwater-based and UV-curable inks. On certain applications,such as blisterpackaging, adhesion requirements are more stringent and will require agood combination of foil, priners, and inks. Consult with suppliers beforecommitting to the job.
Foil adhesion is generally tested with a tape, scratching, or by rubbing thefoil image. When a foil image has poor adhesion, it's generally due to theconstruction of the foil. Our have been formulated to providepermanent adhesion. Remember to perform a tape and scratch resistancetest after the assigned 24 hour post-cure.
TROUBLESHOOTING GUIDE:
DRY LAMINATION (CONVENTIONAL)
Problem Possible Cause Solution
Foil does not transfer at all
Wrong web path
Adhesive is over cured
Adhesive is contaminated
Incorrect foil (hot stamp foil)
Follow recommended web paths from previous pages
Move dryer setting to low and/or increase press
speed
Wash down the print station with Xylene, acetone and vinegar. Let dry before using. Do not
re-use the adhesive in the ink pan
Make sure that foil being used has been config-ured for cold foil
Foil transfers for about 30 minutes and then stops to transfer
Contamination from the anilox cells Wash down the print station with Xylene, acetone and vinegar.
Let dry before using. Adhesive in ink pan can be re-used
Foil transferring at very low speeds
Contamination from the anilox cells Wash down the print station with Xylene,
acetone and vinegar. Let dry before using.
Adhesive in ink pan can be re-used
Foil transfer not even across the web
Nip pressure uneven
Nip roll worn or grooved
Adjust nip pressure until foil transfers evenly
Replace nip roll
Lines showing across the web
Stripping angle not correct
Web is touching the dryer frame
Change stripping angle
Check web path and make sure that the web does not touch the dryer frame.
Cracks across the image
Foil tension is too high
Foil is too loose
Foil is slipping through the nip roll
Foil is sticking to the nip roll.
Decrease tension in the laminating arm and waste wind-up
Replace with a tighter foil
Replace nip with a spare anvil or a driven nip roll
Clean or replace nip roll
Smeared image Incorrect web path Check web path and make sure that the printed image is not touching any idler roll
Rough edges Adhesive is over cured
Low nip pressure
Foil is too tight
Set UV lamp power to medium or low. Increase press speed
Increase nip pressure
Replace with loose foil. change foil path and let
the substrate and foil laminate for a longer period of time
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Problem Possible Cause Solution
Wrinkles Incorrect foil tension
Incorrect foil path
Adjust tension in the laminating arm and waste wind-up until
wrinkles disappear
Check web path and re-web the foil
Faded image Low nip pressure
Nip roll too soft
Increase nip pressure
Replace nip roll with higher durometer nip
Large holes in image Contamination in the plate
Contamination in the substrate
Contamination in the
anvil or nip roll
Clean plate cylinder
Install a web cleaner, a tacky roller or a tacky cloth
Clean anvil and nip roller
Pinholes in image Low nip pressure
Foil is too loose
Increase nip pressure
Replace with a tighter foil
Crowning around edges Incorrect plate cylinder adjustment
Re-adjust plate cylinder
Ghosting Incorrect plate cylinder adjustment
Incorrect web path
Re-adjust plate cylinder
Check web path and make sure that the printed image is not touching any idler roll
Foil filling in reverse Too much nip pressure Reduce nip dwell
Decrease nip pressure
Increase rewind tension
Replace nip with a harder durometer nip
Poor scratch resistance and foil adhesion
Adhesive is not fully cured
UV lamp power is too low
Bad foil
Untested substrate
Decrease running speed
Increase lamp power to high
Replace foil
Contact Beacon Adhesive for substrates not listed under section “Choosing The Right
Adhesive”
DRY LAMINATION (CONVENTIONAL)
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PRESS SET-UP: [1] It is important that a nip station is lo-
cated immediately after the print sta-tion that will be printing the adhesive. Manual and air actuated nips are ac-ceptable. Wet lamination nip station does not require a high degree of pres-sure. A die station will not be required for this application, but a secondary nip station must be located after the UV dryer.
[2] Re-web the press so that the substrate enters the nip station immediately after the impression cylinder. The printed side of the substrate cannot make con-tact with any idler rolls between the im-pression cylinder and the nip station. This will smear the printed image.
[3] Relocation of the UV dryer is not re-quired, but it is best to locate it as close as possible to the laminating arm. An idler roll located directly under the UV lamp is highly recommended. This will ensure that the sub-strate and the foil are perfectly laminated at the point of cure.
[4] For ease of operation, the laminating arm and the waste wind-up must be located within the immediate vicinity of the print station.
WET LAMINATION (CURE-THRU)
Page 24
TIPS: IT IS IMPORTANT THAT A NIP STATION IS LOCATED BEFORE AND AFTER THE UV DRYER, THIS WILL HELP MAINTAIN SUBSTRATE AND FOIL TENSION DURING PRODUCTION RUNS. SINCE THE WET LAMINATION PROCESS DOES NOT REQUIRE A HIGH DEGREE OF PRESSURE, MANUAL, CAM AND AIR ACTUATED NIPS ARE ACCEPTABLE.
Since the wet lamination process does not require a high degree of pressure, manual, cam and air ac-tuated nips are acceptable.
ENTRY NIP: An 85 durometer (or higher) nip roll can be used to laminate the foil onto the substrate. Install this nip roll between the print station and the UV dryer. The foil must be laminated onto the sub-
strate before the UV dryer. A bare idler roll can be used as an anvil under the nip roll. A secondary nip roll must be installed after the UV dryer to strip the foil away from the substrate. When using a nip roll, try to get the highest du-rometer possible. A low durometer nip roll will cause pinholes. It is important that the foil comes in contact with the substrate at the nip point to prevent air entrapment. This can result in a faded foil image. Make sure that the nip roll and the bottom roller are completely clean. Any contamination will transfer to the foiled image.
Page 25
WET LAMINATION (CURE-THRU)
Entry Nip: It is important that the foil enters the entry nip in a 45 degree (or higher) to prevent creasing. It is critical that the foil and substrate is perfectly laminated between the nip and the point of cure. Any crease, air pockets or foil lift will result in poor foil transfer quality. Do not feed the foil di-rectly from the roll, this will crease the foil. Make sure that the idler roll under the UV dryer is level. Any small amount of crease on the web will cause the foil to lift at the point of cure. Exit Nip: A secondary nip assembly must be installed after the UV dryer. This will help isolate the substrate and foil in the UV dryer and provide a consistent results job after job. Do not rewind the foil directly to the rewind roll, this will crease the foil. Make sure that there is an idler roll between the exit nip and the rewind roll. Stripping with the use of and idler roller after the UV dryer will work but the press operator will need to constantly adjust the waste wind up tension to keep the foil laminated onto the substrate. Stripping with the use of the bottom roller will re-sult in the foil “bunching up” right before the idler roll. The amount of foil “bunching up” will in-crease and will eventually ride up to the UV dryer. Remember, unlike standard lamination process, wet lamination cold foil printing uses a small of adhesive. You cannot rely on the adhesive to keep the foil laminated onto the substrate!
Substrate Foil
Entry Nip
UV Dryer
Foil must enter in 45 degree an-
Idler roll
Exit Nip
Foil
Foil
Substrate
Idler roller
Foil
Substrate
Bottom Idler roller
Foil “bunching up”
Correct Way
Wrong Way
Wrong Way
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WET LAMINATION (CURE-THRU) IDLER ROLLS: It is important that the printed substrate does not make any contact with an idler roll between the print station and the entry nip station. When webbing the press, make sure that all idler rolls are bypassed in this area. Since foil transfer is achieved at the point of cure, it is highly recommended that an idler roll is installed under the UV dryer lamp. Make sure that there is a good amount of wrap in this idler roll. This will assure that the foil and the substrate are completely laminated at the point of cure.
UV Lamp
Idler Roll Substrate
Foil
SUGGESTED WEB PATH All of the flexographic and rotary letterpress manufacturers now offer a cold foil option for new press purchases. For existing flexo presses, please refer to the recommended web paths below.
TIPS:
IT IS IMPORTANT THAT THE PRINTED SUBSTRATE DOES NOT MAKE ANY CONTACT WITH AN IDLER ROLL BETWEEN THE PRINT STATION AND THE ENTRY NIP STATION. SINCE FOIL TRANSFER IS ACHIEVED AT THE POINT OF CURE, IT IS HIGHLY RECOMMENDED THAT AN IDLER ROLL IS INSTALLED UNDER THE UV DRYER LAMP. IT IS IMPORTANT THAT THE FOIL ENTERS THE ENTRY NIP IN A 45 DEGREE (OR HIGHER) TO PREVENT CREASING. A SECONDARY NIP ASSEMBLY MUST BE INSTALLED AFTER THE UV DRYER.
ALLIED GEAR
For Allied Gear Flexomaster 3, Flexomaster 4, 300 and 500 Series, the UV dryer might need to be relocated in a higher position to allow room for the entry and exit nip station.
Print Station
UV Dryer
Entry Nip
Exit Nip
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WET LAMINATION (CURE-THRU) SUGGESTED WEB PATH:
Foil Unwind Foil Rewind
Print Station Entry Nip
Exit Nip
UV Dryer
AQUAFLEX/CHROMAS
For Aquaflex LC, DBX, BX, LX, Instraprep and Instaflex, the UV dryer might need to be raised up to allow room for the exit nip station. Install and entry nip station and use the impression roll as the base roll. Install a exit nip station after the UV dryer. Entry and Exit nip stations are available through Aquaflex/Chromas. Install additional idler rollers so that the foil can be webbed correctly. Wet lamination can be accomplished in any print station providing that there is an unwind and re-wind within the immediate vicinity.
GALLUS STACK PRESS For Gallus stack presses, the only location to perform cold foil is the top print station as shown below. Install an entry and exit nip sta-tion on top of the idler rollers before and after the UV dryer. Make sure that the idler rollers are clean and free of marks. If your press has a hot stamping option, use the existing unwind and rewind. If not, you will need to install an unwind and rewind for the foil.
Entry Nip
UV Dryer
Exit Nip
Foil Unwind
Foil Rewind
Print Station
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WET LAMINATION (CURE-THRU) SUGGESTED WEB PATH:
For Comco Commander and MSP, Comco’s laminating nip station is required which will be used as the entry nip station. Replace the nip roll with a hard durometer nip (85 du-rometer or higher). In-stall a exit nip station after the UV dryer. In-stall additional idler rollers so that the foil can be webbed cor-rectly. UV Dryer
Exit Nip
Entry Nip
COMCO WITH OVERHEAD CHILL DRUM
From Foil Unwind
To Foil Rewind
UV Dryer
Chill Drum
Print Station
Entry Nip
Exit Nip
COMCO COMMANDER & MSP From Foil Unwind
From Foil Unwind
Additional Idlers
To Foil Rewind
Entry Nip
Exit Nip
Foil Unwind
Foil Rewind
UV Dryer Exit Nip
Entry Nip Additional Idlers
COMCO CADET
SUGGESTED WEB PATH:
WET LAMINATION (CURE THRU)
Page 29
MARK ANDY
For Mark Andy Scout 2200, 4150 & 4200 install a nip station on top of the idler roller just before the UV dryer. Install an exit nip station after the UV dryer. Install additional idler roll-ers so that the foil can be webbed cor-rectly.
Foil Unwind
Foil Rewind
UV Dryer Exit Nip
Entry Nip
Additional Idlers Exit Nip
Mark Andy Scout or 2200
Mark Andy 4150 or 4200
Additional Idlers
Print Station
Chill Drum
Entry Nip
UV Dryers Exit Nip
From Foil Unwind
To Foil Rewind
Substrate
ILMA 340 For Ilma 340, a lami-nating nip station must be purchased for use as the entry nip. Specify a hard du-rometer nip roll of 85 durometer or higher. Install an exit nip sta-tion between the UV dryers. There is no space available for in-stallation of the exit nip station after the second UV dryer.Install additional idler rollers so that the foil can be webbed cor-rectly.
WET LAMINATION (CURE THRU) SUGGESTED WEB PATH: TIPS:
INSTALL ADDITIONAL IDLER ROLLERS SO THAT THE FOIL CAN BE WEBBED CORRECTLY. MAKE SURE THAT THE NIP ROLL AND THE BOTTOM ROLLER ARE COMPLETELY CLEAN. ANY CONTAMINATION WILL TRANSFER TO THE FOILED IMAGE.
Page 30
NILPETER FA-2500 & FA-3300 For Nilpeter FA-2500 & FA-3300, an entry and exit nip station are avail-able though Nilpeter. Make sure that a high durometer nip roll is speci-fied when ordering the nip assembly. Install additional idler rollers so that the foil can be webbed correctly.
From Foil Unwind
To Foil Rewind
UV Dryer
Exit Nip
Entry Nip
Additional Idlers Press Set-Up on a Nilpeter FA-2500 & FA-3300
ROTOPRESS 3510 & 3513
For Rotopress 3510 and 3513 an entry and exit nip station are available though Rotopress. Make sure that a high durometer nip roll is specified when ordering the nip assembly. Install addi-tional idler rollers so that the foil can be webbed correctly.
Foil Unwind Foil Rewind
UV Dryer
Exit Nip
Entry Nip
Additional Idlers
SUGGESTED WEB PATH:
WET LAMINATION (CURE THRU)
TIPS: JUST LIKE FLEXOGRAPHIC PRINTING, COLD FOIL PRINTING WILL REQUIRE A SKILLED OPERATOR TO CONSISTENTLY PRODUCE HIGH-QUALITY PRODUCTS AND P ROFITABILITY. HALFTONE AND SCREEN WORK HAS A TENDENCY TO “FILL IN” IN THE WET LAMINATION PROCESS.
Page 31
WEBTRON 1000, 1013, 1618 & 1620 For Webtron 1000, 1013, 1618, &1620, a laminating station can be purchased through Webtron which can be used as an entry nip station. Make sure that the nip roll is replaced with a hard du-rometer roll. Install an exit nip station after the UV dryer. Install additional idler rollers so that the foil can be webbed correctly.
Foil Unwind Foil Rewind
UV Dryer
Exit Nip
Entry Nip
Additional Idlers
PROCESS GUIDELINES CHOOSING THE RIGHT JOB: Cold foil printing is possible for any type of job that is normally printed in a flexographic or letterpress. As with any new process, you must carefully re-view the job and consider the current capabilities of your press. Remember that wet lamination cold foil printing will take up a print station, laminating arm and waste wind-up. Just like flexographic printing, cold foil printing will require a skilled operator to consistently produce high-quality products and profitability. PRINTED DESIGN: Since the concept of wet lamination cold foil printing requires the adhesive to cure while it is laminated to the foil, it has its limitations. Halftone and screen work has a tendency to “fill in” in the wet lamination process. For ab-sorbent substrates, more adhesive lay down is required to compensate for the “soak-in”. CHOOSING THE ADHESIVE: There is only one type of adhesive that is currently available for wet lamina-tion. Note that the adhesives for wet and dry lamination are NOT inter-changeable.
Magna-Cryl 4520 - use for paper substrates: There is only one version of Magna-Cryl 4520. This has been tested for use on paper, PP, OPP and BOPP. Magna-Cryl 4520 is a free radical adhesive and can be printed over free radical UV-curable inks, coatings, and water or solvent based inks. Other types of substrates: We are constantly testing new adhesives for film applications. Please con-tact Beacon to get an update on new developments. For specialty and cus-tom film applications, we can perform a test run to study the compatibility of the adhesive to the substrate. OVERCOAT AND LAMINATION: The Magna-Cryl 4520 Series has been designed to withstand the standard tape and scratch resistance tests. Over-coating and lamination are not re-
quired to protect the printed image. CHOOSING THE RIGHT ANILOX: Starting point is a ceramic anilox with 300 line, 6.5 bcm. The logic in-line count is the same as for UV inks. Fine detail will require higher line count while large block areas need lower line counts. We recommend the use of a doctor blade to maintain consistency and even distribution of the adhesive. For uncoated paper stock, use a lower line count to compensate for absorp-tion. PREPARING THE PRINT STATION: The Magna-Cryl 4520 is a free radical adhesive. Although these adhesives are compatible with water and solvent based inks, the print station must be cleaned thoroughly to avoid any adhesive contamination. If the print station was used with water or solvent based ink, it must be washed with vinegar prior to use for cold foil printing. If there is any dried ink in the anilox cells, clean with Xylene and then dry with acetone. Make sure that the solvents have sufficiently evaporated prior to pouring the adhesive. LAMINATING ARM AND WASTE WIND-UP: Set the tensions on both the laminating arm and waste wind-up to “low”. Tension setting should be maintained just enough to remove the slack. High tension will cause the foil to travel faster or slower than the substrate and will result in rough edging and a smeared foil image.
Magna-Cryl 4520 Color: Green
Press Speed: 60-125 fpm Viscosity: 900 cps
TIPS:
REMEMBER THAT WET LAMINATION COLD FOIL PRINTING WILL TAKE UP A PRINT STATION, LAMINATING ARM AND WASTE WIND-UP. SINCE THE CONCEPT OF WET LAMINATION COLD FOIL PRINTING REQUIRES THE ADHESIVE TO CURE WHILE IT IS LAMINATED TO THE FOIL, IT DOES HAVE ITS LIMITATIONS. THE ADHESIVES FOR WET AND DRY LAMINATION ARE NOT INTERCHANGEABLE. THERE IS ONLY ONE VERSION OF MAGNA-CRYL 4520. IT IS A FREE RADICAL ADHESIVE WHICH CAN BE PRINTED OVER FREE RADICAL UV-CURABLE INKS, COATING, AND WATER OR SOLVENT BASED INKS.
WET LAMINATION (CURE THRU)
Page 32
PHOTOPOLYMER PLATES: Cold foil printing does not require a special photopolymer plate. A stan-dard .067 or .045 plate can be used. Standard sticky-back tapes and print cylinders are also required. DRYER SETTINGS: Although the Magna-Cryl 4520 was tested on a 600 watt UV lamp in the 32nm range, most UV dryers installed on flexo presses will easily cure Magna-Cryl 4520. The UV light that cures Magna-Cryl 4520 MUST NOT vary in energy output as the press changes speed. Variations will make it difficult to find the “window” of foil transfer. If your UV dryer has an auto ramp, turn this option “OFF”. You can vary running speed by changing your dryer set-ting to low, medium or high.
DIRT CONTAMINATION: Dirt contamination from the sub-strate is an important issue with cold foil printing. Unlike conven-tional ink printing, cold foil printing is not forgiving when the photopolymer plate and the substrate have been contaminated with dirt. The contamination usually stays in the plate until it is manually removed. Dirt contamination causes large holes in the foil image which are visible to the naked eye. We highly recommend that a web cleaner, or other means of contamination removal, is used to prevent this problem. GASSING: Gassing is a common problem with the wet lamination process and only oc-curs when printing water-based inks. Since water-based inks have alcohol and amines, these emissions can lift the foil and prevent it from laminating with the adhesive at the point of cure. The result is a foil image with small
to large holes. Since all water-based inks have different formula-tions, it is difficult to determine which inks system works best with cold foil printing. AIR POCKETS: Air pockets are the result of bad nip angle. This can be resolved by changing the angle of nip, please refer to page 25 for correct the nip angle.
WET LAMINATION (CURE THRU)
TIPS:
COLD FOIL PRINTING DOES NOT REQUIRE A SPECIAL PHOTOPOLYMER PLATE. THE UV LIGHT THAT CURES MAGNA-CRYL 4520 MUST NOT VARY IN ENERGY OUTPUT AS THE PRESS CHANGES SPEED. SINCE FOIL TRANSFER IS ACHIEVED AT THE POINT OF CURE, IT IS HIGHLY RECOMMENDED THAT AN IDLER ROLL IS INSTALLED UNDER THE UV DRYER LAMP. COLD FOIL PRINTING IS NOT FORGIVING WHEN THE PHOTO-POLYMER PLATE AND THE SUBSTRATE HAVE BEEN CONTAMINATED WITH DIRT.
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Example of air pockets
READY, GET SET… GO COLD!: 1) Mount the photopolymer plate onto the print
cylinder and position the print cylinder into the print station.
2) Prepare the print station using the same pro-
cedure when printing inks. Adjust the plate cyl-inder with a “check gauge” or you can do it manually.
3) Set the fountain roll and doctor blade and pour the adhesive into the ink tray. Make sure that the adhesive is metered correctly. 4) Load the foil onto the laminating arm and web as described in the Recommended Web Path. 5) Apply a slight pressure on the nip roll. 6) Make sure that the UV dryer is “on”, the auto ramp option is “off” and the heat setting is on “high”.
7) Run the press at around 50 fpm and activate the impression. Set the
print cylinder fine adjustment as you would using standard procedures. The cold foil adhesive has been tinted to enable the operator to see the image.
8) Increase the nip pressure until an image appears. Make sure that even
pressure is applied to prevent the substrate from tracking. 9) Adjust the tension on the laminating arm and the waste wind-up and
make sure that the foil is traveling the same speed as the substrate. 10) Increase the speed until the image becomes clearer and full foil transfer is achieved. 11) When increasing speed during a production run, make sure that a sam-ple is tested to ensure that the adhe-sive has been fully cured. 12) Since the adhesive will be fully
cured, a tape or scratch test can be performed at this time.
WET LAMINATION (CURE THRU)
TIPS:
A STANDARD PHOTOPOLYMER PLATE CAN BE USED FOR PRINTING THE COLD FOIL ADHESIVE. SET THE PRINT CYLINDER FINE ADJUSTMENT AS YOU WOULD USING STANDARD PROCEDURES. INCORRECT PLATE CYLINDER ADJUSTMENT CAN RESULT IN CROWNING AROUND THE FOIL IMAGE. MAKE SURE THAT THE AUTO RAMP OPTION IN THE UV DRYER IS ‘OFF”. MAKE SURE THAT THE NIP AND IDLER ROLLS ARE COMPLETELY CLEAN. ANY CONTAMINATION WILL TRANSFER TO THE FOIL IMAGE. SINCE THE ADHESIVE WILL BE FULLY CURED, A TAPE OR SCRATCH TEST CAN BE PERFORMED AT THIS TIME.
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FOIL
♦ Conventional Colors (Color matching is available) ♦ Holographic ♦ Security Images. ♦ Pigmented It is mandatory to use specific foils for the cold foil printing process. A stan-dard hot foil will not transfer when using a cold foil adhesive. When choosing the right foil, remember that although the basic construction is the same, each foil manufacturer has their own proprietary manufacturing techniques and components. Therefore, each foil has its own strengths and weak-nesses. We have tested samples from all of the major manufacturers of foil and found that each one behaved differently depending on the printing job. Each foil has its own properties regarding release, porosity, adhesion, and printability. These factors must be taken into consideration when choosing the right foil for a specific job. There is no one foil construction that can be used for all types of cold foil printing. We recommended that you test the foil for each specific print job.
BASIC COLD FOIL CONSTRUCTION
ADHESION: PRINTABILITY:
TIPS:
IT IS MANDATORY TO USE SPECIFIC FOILS FOR THE COLD FOIL PRINTING PROCESS. A STANDARD HOT FOIL WILL NOT TRANSFER WIHEN USING COLD FOIL ADHESIVE. ALTHOUGH THE BASIC CONSTRUCTION IS THE SAME, EACH FOIL BRAND HAS ITS OWN STRENGTHS AND WEAKNESSES. TO ENSURE SUCCESS, WE NOW PROVIDE OUR
OWN COLD FOIL. THIS FOIL HAS BEEN SPECIALLY FORMULATED TO WORK IN CONJUNCTION WITH ALL OF Magna-Cryl COLD FOIL ADHESIVES.
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WET LAMINATION (CURE THRU)
Foil adhesion is generally tested with a tape, scratching, or by rubbing thefoil image. When a foil image has poor adhesion, it's generally due to theconstruction of the foil. Our have been formulated to providepermanent adhesion. Remember to perform a tape and scratch resistancetest after the assigned 24 hour post-cure.
Issues regarding printability occur when a job requires ink to be printed ontop of a foil image. Our have shown sufficient adhesion to bothwater-based and UV-curable inks. On certain applications,such as blisterpackaging, adhesion requirements are more stringent and will require agood combination of foil, priners, and inks. Consult with suppliers beforecommitting to the job.
To ensure success. we now provide our own This foil has beenspecially formulated to perform with all of our Magna-Crtyl cold foil adhes-ives. Our will work on both dry and wet lamination process and are interchangeable.They are avaiable in:
TROUBLESHOOTING GUIDE Problem Possible Cause Solution
Foil does not transfer at all Wrong web path
Adhesive is under cured
Incorrect foil
Follow-up recommended web paths from previous pages
Move dryer setting to high and/or decrease press speed
Make sure that the foil being used has been
configured for wet lamination cold foil printing
Foil transfers for about 30 minutes and then stops to
transfer
Contamination from the anilox cells Wash down the print station with Xylene, acetone and vinegar. Let dry before using.
Adhesive in ink pan can be re-used
Foil transferring at very low speeds (less than 50 fpm)
Contamination from the anilox cells
UV dryer capacity is too low and not able to penetrate through the foil
Foil is not configured for wet lamination
cold foil printing
Wash down the print station with Xylene, acetone and vinegar. Let dry before using.
Adhesive in ink pan can be re-used
Install a second UV dryer
Replace foil
Foil transfer not even across the web
Nip pressure uneven
Nip roll worn or grooved
Poor alignment of nip roll
Adjust nip pressure until foil transfers evenly
Replace nip roll
Re-install nip roll,
see page 25
Lines showing across the web Stripping angle not correct
Web is touching the dryer frame
Change stripping angle
Check web path and make sure that the web does not touch the dryer frame
Poor foil transfer Not enough nip pressure
Nip roll too soft
Poor alignment of nip roll
Increase nip pressure
Replace nip roll with a higher durometer nip
Reinstall nip roll,
see page 25
Large holes in image Contamination in the plate
Contamination in the substrate
Contamination in the anvil or nip roll
Clean plate cylinder
Install a web cleaner, a tacky roller or a tacky cloth
Clean anvil and nip roll
WET LAMINATION (CURE THRU)
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Problem Possible Cause Solution
Image looks smudgy Too much adhesive
Nip roll too soft
Re-adjust plate cylinder setting
Replace nip roll with a higher durometer nip
Cracks across the image
Foil tension is too high
Foil is sticking to the nip roll.
Decrease tension in the laminating arm and waste wind-up
Clean or replace nip roll
Foil prints in background
Dirt on idler or nip roll Clean the rolls
Smeared image Incorrect web path Check web path and make sure that the printed image is not touching any idler roll
Rough edges or crowning Incorrect print cylinder setting
Low nip pressure
Re-adjust print cylinder setting
Increase nip pressure
Wrinkles Incorrect foil tension
Incorrect foil path
UV dryer too hot
Idler roll not properly aligned
Adjust tension in the laminating arm and waste wind up until wrinkles disappear
Check web path and re-web the foil
Change UV dryer setting to
medium or low or increase running speed
Align idler roll
Faded image and fisheyes
Foil and substrate are not perfectly laminated at the point of cure
Install idler roll under the UV lamp. Adjust foil tension
Pinholes in image Low nip pressure
Not enough adhesive
Increase nip pressure
Replace anilox with a lower count anilox
Poor scratch resistance and foil adhesion
Adhesive is not fully cured
UV lamp power is too low
Bad foil
Untested substrate
Decrease running speed
Increase lamp power to high
Replace foil
Contact Beacon Adhesive for substrates not listed under
section “Choosing The Right Adhesive”
WET LAMINATION (CURE THRU)
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We like to take this opportunity to thank the following companies for their continued support in the further development of the cold foil printing process: FSEA Foil Stamping & Nilpeter, Inc. Chromas/Aquaflex Embossing Association Cincinnati, OH St. Bruno, PQ Canada Portland, OR Any part of this handbook cannot be reproduced without the written consent of Beacon Adhesives.