Teknik Etsa kimia untuk logam dan kaca

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DAFTAR ISI

Pasal Etsa Kaca BAB I PENDAHULUAN

BAB II CONTOH KREASI-KREASI ETSA GELAS

BAB III APLIKASI GLASS ETCHING

1. METODE CELUP 2. METODE SANDBLASTING 3. METODE OLES

BAB IV FORMULASI ETCHANT KONVENSIONAL

1. (Formula I) Etching konvensional 2. Formula II

BAB V FORMULASI ETCHANT MODERN BAB VI FORMULASI ETCHANT MODERN LAINNYA Pasal etsa Logam 1.Pengantar 2. Seputar etsa logam 3.Komponen etsa logam

3.1. Substrat ( logam ) 3.2. Etchant 3.3. Resist 3.4. Container 3.5. Safety equipment

4. Prosedur pengetsaan 4.1 . Pembuatan desain grafis. 4.2 . Persiapan larutan etsa 4.3 . Formula etsa

4.3.1 Etsa Kuningan dan Tembaga 4.3.2 Besi dan Stainless Steel 4.3.3 Alumunium

5.How to make a printed circuit board. 5.1. EXPOSING THE BOARD 5.2. DEVELOPMENT AND ETCHING 5.3. DRILLING

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Pasal Etsa Kaca BAB I PENDAHULUAN

Glass etching adalah suatu teknik untuk melukai permukaan gelas dengan bahan kimia atau dengan teknik sanblasting sehingga permukaan kaca atau gelas tersebut menjadi kabur atau seperti bersalju (frosted). Aplikasi teknik ini adalah untuk layar televisi, bola lampu dan untuk karya seni diatas permukaan kaca. Bahan kimia yang digunakan untuk etching dinamakan etchant. Bahan etchant yang digunakan dalam glass etching secara garis besar ada 2 yaitu Hidrofluoric Acid (dalam bentuk cairan) dan garam fluoride (dalam bentuk serbuk/powder). Kedua bahan inilah yang menjadi bahan aktif yang dapat melukai permukaan kaca/gelas.Dalam hal ini tentu saja diperlukan zat aditif-aditif lain untuk menunjang proses etching. Saat ini etching kaca dengan menggunakan hydrofluoric acid telah banyak ditinggalkan karena masalah keselamatan kerja.

ETCHING

KONVENSIONAL

ETCHING MODERN

Bahan aktif hidrofluoric acid Bahan aktif garam fluoride

Memerlukan peralatan keselamatan

kerja seperti sarung tangan, penutup

muka dan exhaust fan.

Selama tidak mendapat kontak

dengan alkali sehingga tidak

membentuk gas hidrogenfluoride dan

gas amoniak, walaupun terjadi kontak

dengan kulit tak akan ada masalah.

Aplikasi spesial/khusus Dapat diaplikasikan sehari-hari

Memerlukan bahan masking yang

tahan etchant seperti asphaltum,

paraffin yang sulit handlingnya.

Metode maskingnya bisa memakai

pena minyak, cat resin, cat akrilik,

selotip, silk screen printing, dll.

Sama seperti metode etching konvensional, metode sandblasting juga memerlukan peralatan keselamatan kerja yang banyak karena dapat menyebabkan masalah paru-paru karena debu yang ditimbulkannya. Cara meng-etching juga bervariasi, bisa dengan pencelupan (jika etchant dalam bentuk cair), bisa juga dengan cara dioleskan atau dikuaskan pada permukaan (jika etchant dalam bentuk pasta). Dalam buku ini akan dibahas bagaimana membuat bahan etchant dalam bentuk cair dan pasta dan juga cara-cara aplikasinya baik cara konvensional dan cara modern.

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BAB II

CONTOH KREASI-KREASI ETSA GELAS

1. Contoh I (Frosted etched glass)

2. Contoh II (Etched Color Filled)

3. Contoh III (Frosted etched, black filled, frosted background)

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BAB III

APLIKASI GLASS ETCHING

2. METODE CELUP

3. METODE SANDBLASTING

4. METODE OLES

Letakkan gelas yang akan di-etching ke dalam holder/tatakan

Rekatkan stensil di atas gelas dengan menggunakan selotip atau double tape

Oleskan etchant ke permukaan gelas dan biarkan selama beberapa waktu

Pindahkan stensilnya dan …….. jadi.

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BAB IV

FORMULASI ETCHANT KONVENSIONAL

2. (Formula I) Etching konvensional

Cara etching dengan me-masking/menutupi permukaan gelas dengan bahan

yang tahan asam seperti asphaltum, paraffin lalu mengaplikasikan acid /etchant dan

kemudian menghapus wax tersebut adalah lama dan kurang akurat.

Cara baru yang dibahas disini adalah dengan cara membentuk

karakter/leter/huruf/gambar sesuai dengan betuk dan ukuran yang diindinkan dengan

lembaran tembaga. Kemudian disusun keatas permukaan kaca sehingga membentuk

suatu kata atau kalimat. Huruf ini direkatkan ke permukaan dengan menggunakan

beban atau klip atau kayu panjang. Kemudian sisa permukaan yang tidak terkover

ditutupi dengan lelehan paraffin, segera setelah paraffin mengeras, karakter/huruf tadi

diangkat. Hal ini akan meninggalkan lubang di kaca. Kemudian lubang tersebut diisi

dengan hidrofluoric acid dan dibiarkan selama beberapa menit. Setelah selesai, asam

dipindahkan dan permukaan dibersihkan dengan air.

3. Formula II

MASKING Kaca dimasking dengan material tahan etchant, dalam hal ini : Bitumen judea + turpentine

PRE-ETCHING Kaca dietching dengan hidrofluoric acid yang telah dilarutkan, selama beberapa detik, kemudian dibersihkan dengan air.

JADI

ETCHING Kaca dietching dengan campuran hidrofluoric acid dan sodium carbonate selama 30 menit, kemudian dibersihkan dengan air.

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3. Formula III a. Formulasi : - HF (70%) 3 gallon

- H2SO4 (96%) 2 gallon - Ammonium Sulfat 12 pound - Glycerin 3 gallon - Air 2 gallon Note: * HF : 0.78 part/w * H2SO4 : 1.10 part/w * Ammonium Sulfat : 0.42 part/w * Glycerin : 1.17 part/w * Air : 1 part/w * temperatur formula diatas akan naik pada saat mixing, sehingga harus didinginkan dahulu sebelum dipakai.

b. Objek : - panel kaca flat c. Caranya : - objek tersebut diatas dicuci dengan air

mengalir kemudian sisa air dikeringkan. - objek tersebut dimasking

- formula diatas didinginkan dulu sampai suhunya 65o F, lalu objek dicelupkan ke dalamnya selama 30 detik. - kemudian objek-objek tadi diangkat dan dicuci dengan air.

d. Hasil : area yang tidak dimasking telah nonrflektif, tetapi masih ada sisa transparansinya.

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BAB V FORMULASI ETCHANT MODERN MENURUT

FRANK LUTFIE PENDAHULUAN

Resep berbasis Ammonium Bifluoride tanpa HF ini, metode maskingnya bisa memakai : pena minyak, cat resin, cat akrilik, selotip, silk screen printing, dll.

Pada metode frosting/etching menggunakan etchant konvensional yang mengandung fluorine, peralatan keselamatan kerja seperti sarung tangan, penutup muka dan exhaust fan sangatlah mutlak diperlukan. Dengan komposisi yang baru, selama ammonium bifluoride tidak mendapat kontak dengan alkali sehingga tidak membentuk gas hidrogenfluoride dan gas amoniak, walaupun terjadi kontak dengan kulit tak akan ada masalah. KANDUNGAN DALAM FORMULASI ETCHANT

1. Bahan Aktif Berfungsi meng-etch permukaan kaca/gelas Contoh : sodium fluoride, potassium fluoride, ammonium fluoride, sodium bifluoride, potassium bifluoride, dan ammonium bifluoride.

2. Gelling agent Berfungsi membentuk gel pada komposisi etchant Contoh : hydroxypropyl celullose, hydroxyethyl celullose, methyl celullose, carboxymethyl celullose, sodium carboxymethyl celullose, sodium alginate, arabic gum, gum tragacanth, xanthan gum, bentonite, veegum, gelatin, dll.

3. Surfactant Berfungsi sebagai wetting agent, sehingga komposisi etchant dpt tersebar merata pada permukaan gelas. Contoh : - anionic : dodecylbenzene sodium sulfonate, alkylbenzene sodium sulfonate, dll. - nonionic : polyoxyethylene nonylphenyl ether, sorbitan monolaurate, sorbitan monopalmitate, dll. - amfoteric : dimethyl alkylbetain, imidazoline, dll. - cationic : quartenary ammonium salt, dll.

4. Pengatur pH Contoh : acetic acid, citric acid, phosphoric acid, dll.

5. Sucrose Berfungsi sebagai stabilizer dan flow modifier

6. Dye/pewarna 7. Solvent organik larut air

Juga berfungsi seperti surfactant Contoh : - glikol grup : propylene glycol, ethylene glycol, diethylene

glycol, dll. - alkohol grup : methanol, ethanol, isopropyl alcohol, dll. - gliserin.

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1. RESEP I e. Formulasi : - Am. Bifluoride 12 gram

- Air 100 ml - Brilliant Blue FCF 0.5 mg - Propylene Glycol 200 ml

Note: * komposisi total : 300ml * Am. Bifluoride : 4 w/v% * Air : 33.3 v/v % * propylene glycol : 66.7 v/v%

f. Objek : - panel kaca flat panjang 100mm, lebar 100mm, tebal 2mm. - sebuah gelas mempunyai diameter luar 50mm, tinggi 95mm, dan tebal 1mm. - sebuah cermin dengan diameter luar 900mm

g. Caranya : - semua objek tersebut diatas dicuci dengan air mengalir kemudian sisa air dikeringkan. - objek tersebut dimasking dengan cara melukis area yang diinginkan dengan pena minyak warna

biru. - objek tersebut dicelupkan kedalam formula diatas selama 5-15 menit. - kemudian objek-objek tadi diangkat dan dicuci dengan air.

h. Hasil : area yang tidak dimasking telah ter-FROSTED i. Catatan

1. Kerapatan kekeruhan (frosted density) akan bertambah jika konsentrasi ammonium bifluoride dinaikkan, begitu pula dengan waktu pencelupan, waktu pencelupan semakin cepat jika konsentrasi ammonium bifluoride dinaikkan.

2. Telah ditemukan bahwa tingkat kerapatan dan keseragaman kekeruhan (frosted image) yang paling baik adalah jika konsentrasi ammonium bifluoride adalah 3-5w/v% dan waktu pencelupan 10 menit.

3. Jika konsentrasi ammonium bifluoride lebih dari 5w/v% kerapatan kekeruhan yang baik tidak dapat dicapai karena permukaan kaca dimakan oleh asam secara parsial.

4. Dibandingkan dengan glycols, glycerin dapat menyebabkan turunnya tingkat (kerapatan) kekeruhan.

2. RESEP II j. Formulasi : - Am. Bifluoride 12 gram

- Air 100 ml - Brilliant Blue FCF 0.5 mg - Glycerin 300 ml Note: * komposisi total : 400ml * Am. Bifluoride : 3 w/v% * Air : 25 v/v % * Glycerin : 75 v/v%

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k. Objek : - panel kaca flat panjang 100mm, lebar 100mm, tebal 2mm. - sebuah gelas mempunyai diameter luar 50mm, tinggi 95mm, dan tebal 1mm. - sebuah cermin dengan diameter luar 900mm

l. Caranya : - semua objek tersebut diatas dicuci dengan air mengalir kemudian sisa air dikeringkan. - objek tersebut dimasking dengan cara melukis area yang diinginkan dengan pena minyak warna

biru. - objek tersebut dicelupkan kedalam formula diatas selama 10 menit. - kemudian objek-objek tadi diangkat dan dicuci dengan air.

m. Hasil : area yang tidak dimasking telah ter-FROSTED n. Catatan

1. Telah ditemukan bahwa tingkat kerapatan dan keseragaman kekeruhan (frosted image) yang paling baik adalah volume rasio antara aq. solution (ammonium bifluoride, dye, dan air) dan glycols atau glycerin adalah 1:2 sampai 1:3.

2. Dibandingkan dengan glycols, glycerin dapat menyebabkan turunnya tingkat (kerapatan) kekeruhan.

3. RESEP III o. Formulasi : - Am. Bifluoride 16 gram

- Air 100 ml - Brilliant Blue FCF 0.5 mg - Propylene Glycol 200 ml - PEG 200 100 ml Note: * komposisi total : 400ml * Am. Bifluoride : 4 w/v% * Air : 25 v/v % * propylene glycol : 50 v/v% * PEG 200 : 25 v/v%

p. Objek : - panel kaca flat panjang 100mm, lebar 100mm, tebal 2mm.

q. Caranya : - semua objek tersebut diatas dicuci dengan air mengalir kemudian sisa air dikeringkan. - objek tersebut dimasking dengan cara melukis area yang diinginkan dengan pena minyak warna

biru. - objek tersebut dicelupkan kedalam formula diatas selama 5-10 menit. - kemudian objek-objek tadi diangkat dan dicuci dengan air.

r. Hasil : area yang tidak dimasking telah ter-FROSTED

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s. Catatan 1. Kerapatan kekeruhan (frosted density) akan berkurang jika konsentrasi PEG

dan berat molekul rata-rata PEG (keduanya) dinaikkan. 2. Pada teknik glass etching, dipilih PEG yang mempunyai berat molekul antara

200 sampai 400, selama bentuknya masih likuid/cair. 3. Sebagaimana jika konsentrasi glycerin dinaikkan, tingkat (kerapatan)

kekeruhan akan menurun, seperti pada kasus PEG. Hasil yang sama dapat terjadi jika propylene glycol diganti dengan diethylene glycol.

4. RESEP IV t. Formulasi : - Am. Bifluoride 15 gram

- Air 100 ml - Brilliant Blue FCF 0.5 mg - Propylene Glycol 300 ml - Isopropyl Alcohol 100 ml

Note: * komposisi total : 500ml * Am. Bifluoride : 3 w/v% * Air : 20 v/v % * propylene glycol : 60 v/v% * Isopropyl alcohol : 20 v/v%

u. Objek : - panel kaca flat panjang 100mm, lebar 100mm, tebal 2mm.

v. Caranya : - semua objek tersebut diatas dicuci dengan air mengalir kemudian sisa air dikeringkan. - objek tersebut dimasking dengan cara melukis area yang diinginkan dengan pena minyak warna

biru. - objek tersebut dicelupkan kedalam formula diatas selama 5-10 menit. - kemudian objek-objek tadi diangkat dan dicuci dengan air.

w. Hasil : area yang tidak dimasking telah ter-FROSTED x. Catatan : Kerapatan kekeruhan (frosted density) akan berkurang jika

konsentrasi alkohol dinaikkan, hasil yang serupa didapat dengan menggunkan alkohol jenis lainnya, tetapi sulit untuk mencapai densitas kekeruhan yang uniform.

5. RESEP V y. Formulasi : - Am. Bifluoride 12 gram

- Sorbitol 20 gram - Air 100 ml - Brilliant Blue FCF 0.5 mg - Propylene Glycol 300 ml

Note: * komposisi total : 400ml * Am. Bifluoride : 3 w/v% * Sorbitol : 5 w/v% * Air : 25 v/v % * propylene glycol : 75 v/v%

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z. Objek : - panel kaca flat panjang 100mm, lebar 100mm, tebal 2mm.

aa. Caranya : - semua objek tersebut diatas dicuci dengan air mengalir kemudian sisa air dikeringkan. - objek tersebut dimasking dengan cara melukis area yang diinginkan dengan pena minyak warna

biru. - objek tersebut dicelupkan kedalam formula diatas selama 5-10 menit. - kemudian objek-objek tadi diangkat dan dicuci dengan air.

bb. Hasil : area yang tidak dimasking telah ter-FROSTED cc. Catatan

1. Kerapatan kekeruhan (frosted density) akan bertambah jika konsentrasi sorbitol dinaikkan.

2. Tetapi jika setengah atau sepertiga bagian propylene glycol diganti dengan solven organik lain yang larut air, tingkat (kerapatan) kekeruhan bisa berkurang. Jadi tingkat (kerapatan) kekeruhan tidakk selalu tergantung pada konsentrasi sorbitol.

6. RESEP VI dd. Formulasi : - Am. Bifluoride 12 gram

- polyoxyethylene octylphenyl ether** 1.5 gram - Air 100 ml - Brilliant Blue FCF 0.5 mg - Propylene Glycol 200 ml

Note: * komposisi total : 300ml * Am. Bifluoride : 4 w/v% * polyoxyethylene octylphenyl ether : 0.5 w/v% * Air : 33.3 v/v % * propylene glycol : 66.7 v/v% ** or polyoxyetthylene nonylphenyl ether, polyoxyethylene sorbitan monolaurate, lignin calcium sulfonate, and dodecyl benzene sodium

sulfonate. ee. Objek : - panel kaca flat panjang 100mm, lebar 100mm,

tebal 2mm. ff. Caranya : - semua objek tersebut diatas dicuci dengan air

mengalir kemudian sisa air dikeringkan. - objek tersebut dimasking dengan cara melukis area yang diinginkan dengan pena minyak warna

biru. - formula etchant diatas disemprotkan ke objek, kemudian dibiarkan selama 5 menit. - kemudian objek-objek tadi dicuci dengan air.

gg. Hasil : area yang tidak dimasking telah ter-FROSTED

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hh. Catatan 1. Surfactant tidak terlalu berpengaruh pada tingkat kerapatan kekeruhan, tetapi

menaikkan daya rekat etchant ke kaca. Masing-masing surfaktan dapat menghasilkan efek tersebut tentu saja dengan kekuatan yang berbeda-beda.

7. RESEP VII ii. Formulasi : - Am. Bifluoride 12 gram

- Sucrose 15 gram - Air 100 ml - Brilliant Blue FCF 0.5 mg - Propylene Glycol 300 ml

Note: * komposisi total : 400ml * Am. Bifluoride : 4 w/v% * Sucrose : 5 w/v% * Air : 33.3 v/v % * propylene glycol : 66.7 v/v%

jj. Objek : - panel kaca flat panjang 100mm, lebar 100mm, tebal 2mm.

kk. Caranya : - semua objek tersebut diatas dicuci dengan air mengalir kemudian sisa air dikeringkan. - objek tersebut dimasking dengan cara melukis area yang diinginkan dengan pena minyak warna biru. - objek tersebut dicelupkan kedalam formula diatas selama 5-10 menit

- kemudian objek-objek tadi diangkat dan dicuci dengan air. ll. Hasil : area yang tidak dimasking telah ter-FROSTED

mm. Catatan 1. Kerapatan kekeruhan (frosted density) akan bertambah jika konsentrasi

sucrose dinaikkan. 2. Tetapi jika setengah atau sepertiga bagian propylene glycol diganti dengan

solven organik lain yang larut air, tingkat (kerapatan) kekeruhan bisa berkurang. Jadi tingkat (kerapatan) kekeruhan tidak selalu tergantung pada konsentrasi sucrose.

8. RESEP VIII nn. Formulasi : - Am. Bifluoride 20 gram

- Air 100 ml - Brilliant Blue FCF 0.5 mg - Propylene Glycol 100 ml

Note: * komposisi total : 200ml * Am. Bifluoride : 10 w/v% * Air : 50 v/v % * propylene glycol : 50 v/v%

oo. Objek : - panel kaca flat panjang 100mm, lebar 100mm, tebal 2mm. - sebuah gelas mempunyai diameter luar 50mm, tinggi 95mm, dan tebal 1mm. - sebuah cermin dengan diameter luar 900mm

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pp. Caranya : - semua objek tersebut diatas dicuci dengan air mengalir kemudian sisa air dikeringkan. - objek tersebut dimasking dengan cara melukis area yang diinginkan dengan pena minyak warna biru.

- objek tersebut dicelupkan kedalam formula diatas selama 5-10 menit. - kemudian objek-objek tadi diangkat dan dicuci dengan air.

qq. Hasil : area yang tidak dimasking telah ter-FROSTED rr. Catatan

1. Kerapatan kekeruhan (frosted density) akan bertambah jika konsentrasi ammonium bifluoride dinaikkan, begitu pula dengan waktu pencelupan, waktu pencelupan semakin cepat jika konsentrasi ammonium bifluoride dinaikkan.

2. Walaupun begitu, densitas kekeruhan yang istimewa kadang tidak dapat dicapai karena permukaan kaca dimakan oleh asam secara parsial.

9. RESEP IX ss. Formulasi : - Am. Bifluoride 12 gram

- dodecylbenzene sodium sulfonate 1.2 gram - Air 200 ml - Brilliant Blue FCF 0.5 mg - Propylene Glycol 100 ml Note: * komposisi total : 300ml * Am. Bifluoride : 8 w/v% * dodecylbenzene sodium sulfonate : 0.8 w/v% * Air : 66.7 v/v % * propylene glycol : 33.3 v/v%

tt. Objek : - panel kaca flat panjang 100mm, lebar 100mm, tebal 2mm. uu. Caranya : - semua objek tersebut diatas dicuci dengan air

mengalir kemudian sisa air dikeringkan. - objek tersebut dimasking dengan cara melukis area yang diinginkan dengan pena minyak warna biru. - objek tersebut dicelupkan kedalam formula diatas selama 5-10 menit.

- kemudian objek-objek tadi dicuci dengan air. vv. Hasil : area yang tidak dimasking telah ter-FROSTED ww. Catatan

1. Kerapatan kekeruhan (frosted density) akan bertambah jika konsentrasi ammonium bifluoride dinaikkan, begitu pula dengan waktu pencelupan, waktu pencelupan semakin cepat jika konsentrasi ammonium bifluoride dinaikkan. Walaupun begitu permukaan kaca bisa dimakan oleh asam secara parsial, dan pada permukaan yang keruh terdapat bagian yang kasar. Dengan adanya surfaktan, problem tersebut dapat diatasi.

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10. RESEP X xx. Formulasi : - Am. Bifluoride 12 gram

- Air 100 ml - Light Green SFY 0.5 mg - Propylene Glycol 200 ml - Hydroxypropyl celullose 10.5 gram Note: * komposisi total : 300ml * Am. Bifluoride : 4 w/v% * Air : 33.3 v/v % * propylene glycol : 66.7 v/v% * Hydroxypropyl celullose : 3.5 w/v%

yy. Objek : - panel kaca flat panjang 100mm, lebar 100mm, tebal 2mm. - sebuah gelas mempunyai diameter luar 50mm, tinggi 95mm, dan tebal 1mm. - sebuah cermin dengan diameter luar 900mm

zz. Caranya : - semua objek tersebut diatas dicuci dengan air mengalir kemudian sisa air dikeringkan. - objek tersebut dimasking dengan cara melukis area yang diinginkan dengan pena minyak warna

biru. - formula diatas dioleskan atau dikuaskan ke permukaan kaca dan didiamkan sampai 5-10 menit. - kemudian objek-objek tadi diangkat dan dicuci dengan air.

aaa. Hasil : area yang tidak dimasking telah ter-FROSTED bbb. Catatan

1. Untuk aplikasi etchant gel dengan kuas, konsentrasi hydroxypropylcelullose yang paling baik adalah 1 sampai 3.5w/v%. Untuk aplikasi dengan pengolesan konsentrasi hydroxypropylcelullose yang paling baik adalah 4 w/v% atau lebih. Tingkat kekentalan rata-rata hydroxypropyl celullose dipilih antara 150-400 mps (2% sol. pada 20o C) untuk mendapatkan tingkat kekeruhan yang pas dan untuk kemudahan dalam aplikasinya.

2. Jika gelling agent digunakan selain hydroxypropylcelullose, dibutuhkan jumlah yang lebih banyak untuk membuat komposisi gel homogen seperti yang dilakukan oleh hydroxypropylcelullose. Dan juga dengan gelling agent selain hydroxypropylcelullose, sulit didapat tingkat kekeruhan dan keseragaman kekeruhan yang pas.

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BAB VI FORMULASI ETCHANT MODERN LAINNYA

1. Menurut Armour Product Corporation

Nama Produk : “Armour Etch”

RESEP : 1. Campuran Fluoride : 30-60% 2. Titanium Dioxide : 1-5% 3. Citric Acid : 10-30%

2. Menurut McKay Chemical Company

Nama Produk : “Velvet etch corossive liquid un. No. 1760”

RESEP : 1. Ammonium Bifluoride : 6% 2. Sodium Bifluoride : 28% 3. Filler Solids : 22% 4. Air : 41% 5. Filler lainnya : 3%

3. Menurut Rafael Benitez RESEPNYA A. Formulasi cairan pembersih

- sodium carbonate (dehydrated) 46 gram - air 1 liter - amoniak 17 gram - dishwashing deterjen 2 gram - etanol 50 gram - polyethylene oxide sorbitan monooleate (polysorbate 80) 5 gram caranya : larutkan sodium carbonate dalam air, masukkan amoniak. setelah larut masukkan deterjen, etanol dan polysorbate 80.

B. Formulasi cairan penetralisir - potassium carbonate 1000 gram - air 1 liter caranya : larutkan potassium carbonate dalam air yang sudah dipanaskan pada suhu 80oC, biarkan sampai campuran mencapai suhu kamar, dan disaring.

C. ormulasi pasta etchant - ammonium bifluoride … - air (deionized) …

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- barium sulfat (99%, 200mesh) … caranya : larutkan ammonium bifluoride pada air yang sudah dipanaskan sampai 95oC, sampai mencapai saturasi. Larutan ini kemudian dibiarkan mencapai suhu kamar hingga membentuk larutan

bening dan terdapat residu kristal. Pisahkan kristal tersebut dan campurkan serbuk barium sulfat ke dalam larutan bening itu sampai bentuk pasta yang dapat dikuaskan ke permukaan verti- kal tanpa ndlewer.

Percobaan III

Glass Etching Pasta tanpa Filler ccc. Formulasi : - ammonium bifluoride 22 %(sebagai bahan aktif )

- propylene glycol 24 % (sebagai dispersing dan wetting agent)

- xanthan gum 4 % (sebagai thickener) - air 50% (sebagai carrier)

ddd. Caranya : - panaskan air sampai mencapai suhu 50o C - larutkan ammonium bifluoride dengan air

- panaskan propylene glycol sampai suhu 50o C masukkan xanthan gum dan aduk sampai rata - campur kedua larutan tersebut, aduk sampai rata Percobaan IV Glass Etching Pasta tanpa Filler dengan Pewarna Titanium Dioxide

a. Formulasi: - ammonium bifluoride 22 %(sebagai bahan aktif ) - propylene glycol 24 %(sebagai dispersing dan wetting agent) - xanthan gum 4 %(sebagai thickener) - air 45% (sebagai carrier) - pasta titanium dioxide 5%(sebagai pewarna)

b. Caranya : - panaskan air sampai mencapai suhu 50o C - larutkan ammonium bifluoride dengan air - panaskan propylene glycol sampai suhu 50o masukkan xanthan

gum dan aduk sampai rata lalu masukkan pigmen pasta, aduk sampai rata

- campur kedua larutan tersebut, aduk sampai rata Percobaan V Glass Etching Pasta dengan Filler Barium Sulfate

c. Formulasi : - ammonium bifluoride 22 %(sebagai bahan aktif ) - propylene glycol 24.5 % (sebagai dispersing dan wetting agent)

- xanthan gum 0.5 % (sebagai thickener) - air 45 % (sebagai carrier) - barium sulfate 8% (sebagai pewarna)

a. Caranya : - panaskan air sampai mencapai suhu 50o - larutkan ammonium bifluoride dengan air

- panaskan propylene glycol sampai suhu 50o C masukkan xanthan gum dan aduk sampai rata lalu masukkan barium sulfate, aduk sampai rata - campur kedua larutan tersebut, aduk smpai rata

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Pasal etsa Logam 1.Pengantar Metal etching, also known as "milling" or "machining," is the production of a depressed design on a metal plate by cutting lines through a protective coating and then applying corrosive acid that removes the metal under the lines. Sometimes, the plates are smoked so that the lines will be more visible. Etching is used to create metal industrial parts, which may have many small grooves or holes. It is also used as a decorative finish on many metals. It allows a metal to meet weight demands, as well, by dissolving an appropriate layer of the surface. While metal etching using acid remains the most common method, there are now many others that do not employ the use of acid. The acid used in the metal etching process is controlled in several ways. Most often, a hard, waxy, acid-resistant ground is applied to the plate. A design is scratched into the surface with a sharp point, exposing lines that are attacked by the acid. A soft ground is sensitive to pressure. Paper is placed on the part. A pencil is then used to make the lines of varying densities, which allows more or less acid through, depending on the pressure applied. Faux-bite results from small amounts of acid leaking through the ground, creating minor pitting and burning on the surface. It can be removed by burnishing, polishing or smoothing the surface.

A broad range of metals can be used during the acid-based processes, such as stainless steel, copper, brass, nickel and silver alloy. Other metals can be etched using gas or electric-based processes. If a metal piece is in need of fine grooves, laser etching is often used. Abrasive etching with high-compression air is another option. In this process, abrasives, such as aluminum oxide or sand, are sometimes blasted in place of laser technology, when isolated areas are being worked on. Photo chemical etching, which is the most common etching method, is a low-cost process that provides high quality, fast turnaround and precision accuracy unavailable in other etching processes. This process also allows flexibility in the design of parts, as changes can be made quickly, simply and cost-effectively. Examples of etched metal products in the medical field are stents, cathodes and implants. Brake rotors and fuel cell plates are made for the automotive industry. The sign and plaque industry heavily relies on the use of etched metals. Jewelry production and other artistic portions of industry use metal etching to create fine lines for intricate details. Photochemical etching produces business cards, logo name plates, panel covers and

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promotional items for the commercial sector. Metal etching is also used to create longer lasting stencils for the woodworking and art fields.

2. Seputar etsa logam Etching is an intaglio method of printmaking in which the image is incised into the surface of a metal plate using an acid. The acid eats the metal, leaving behind roughened areas, or if the surface exposed to the acid is very narrow, burning a line into the plate. The process is believed to have been invented by Daniel Hopfer (circa 1470-1536) of Augsburg, Germany, who decorated armour in this way, and applied the method to printmaking. Etching is also used in the manufacturing of printed circuit boards and semiconductor devices. There are many ways for the printmaker to control the acid's effects. Most typically, the surface of the plate is covered in a hard, waxy ground that resists acid. The printmaker then scratches through the ground with a sharp point, exposing lines of metal that are attacked by the acid. Once the drawing in the ground is finished, the plate is submerged in acid for a period of time; longer submersion means that deeper lines are etched. The ground may be removed, or the artist may continue drawing in it, etching it again in acid to deepen existing lines while adding new lines. The ground may also be reapplied to protect existing lines while adding new ones. The ground may be removed and the plate printed to see its current printing state, to be followed by more work (or other techniques, such as aquatint, drypoint, or engraving); thus, many of Rembrandt's etchings exist in several distinct forms, with the fin , "accepted" version apparently preceded by many artist's proofs. A "soft" ground may also be used--a ground that is sensitive to pressure. The soft ground is applied to the plate, and the artist removes it by putting paper on top and drawing on the paper. The varying pressure of the pencil on the paper lifts the soft ground in a likewise varying amount, in a particulate way--rather than removing the ground, its density is decreased, allowing more or less acid through. The effect is much like that of particulate media like chalk, charcoal, or pencil: the image burned into the plate is composed of greater and lesser densities of minuscule pitting, rather than sharp, continuous lines. Minor variations involve putting a soft ground on a plate along with some textured surface (such as fabric or crumpled plastic wrap or paper), and then running the combination through a press, transferring the texture to the plate. By the middle of the nineteenth century, the copper-engraving lost of importance due to the invention of the lithography. Nevertheless, even today it is a famous art form, which is still appreciated by it´s collectors. But also the of actinic etching is still applied today, when printing magazines and newspapers. Aquatint is a variation of the etching in which particulate resin is evenly distributed on the plate, then heated to form a screen ground of uniform but less than perfect density. After etching, the result is a uniformly roughened (i.e., darkened) plate that may then be drawn on by smoothing it, creating the image from dark-to-light rather than the reverse. The printing-procedure the plate is done by covering the surface with ink, then rubbing the ink off the surface with tarlatan cloth or newsprint, leaving ink in the roughened areas and lines. Damp paper is placed on the plate, and both are run through a printing press; the pressure forces the paper into contact with the ink, transferring the image (c.f., chine-collé). Unfortunately, the pressure also subtly degrades the image in the plate, smoothing the roughened areas and closing the lines; a copper plate is good for, at most, a few hundred printings of a strongly etched imaged before the degradation is considered too great by the artist. At that point, the artist can manually restore the plate by re-etching it,

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essentially putting ground back on and retracing her lines; alternately, plates can be electro-plated before printing with a harder metal to preserve the surface. Zinc is also used, because as a softer metal, etching times are shorter; however, that softness also leads to faster degradation of the image in the press. Faux-bite is common in etching, and is the effect of minuscule amounts of acid leaking through the ground to create minor pitting and burning on the surface. This incidental roughening may be removed by smoothing and polishing the surface, but artists often leave faux-bite, or deliberately court it by handling the plate roughly, because it's viewed as a desirable mark of the process. Drypoint is a printmaking technique of the intaglio family, in which an image is incised into a plate (typically copper, zinc, or plexiglas) by scratching the surface with a hard, sharp metal point. This technique is different from engraving, in which the incisions are made by gouging. While engraved lines are very smooth and hard-edged, drypoint scratching leaves a rough burr at the edges of each line. This burr gives drypoint prints a characteristically soft, and sometimes blurry, line quality. Because the pressure of printing quickly destroys the burr, drypoint is useful only for very small editions. To counter this, and allow for longer print runs, electro-plating can harden the surface of a plate The engraving process Engravers use a hardened steel tool called a burin to cut the design into the surface, most traditionally a copper plate. Gravers come in a variety of shapes and sizes that yield different line types. The burin produces a unique and recognizable quality of line that is characterized by its steady, deliberate appearance and clean edges. The angle tint tool has a slightly curved tip that is commonly used in printmaking. Florentine liners are flat-bottomed tools with multiple lines incised into them, used to do fill work on larger areas. Flat gravers are used for doing fill work on letters, as well as most musical instrument engraving work. Round gravers are commonly used on silver to create bright cuts, as well as other hard-to-cut metals such as nickel and steel. Burins are either square or elongated diamond-shaped and used for cutting straight lines. Other tools such as mezzotint rockers, roulets and burnishers are used for texturing effects coloured etching Etchings, being initially printed in one basic colour can be each individually hand-coloured after the printing process is finished. Colouring is done by using water colours and crayons coloured etching from the beginning Before printing the image, the plate is being prepared with different colours, so that the resulting print needs not to be coloured with water-colours or crayons. This process is very complex and takes much time. Therefore, it does not allow a unique production print. Printing on coloured paper When applying white ink on blue or black-coloured paper, the effect of a chalk-drawing can be achieved. Artists used this printing-technique to duplicate and imitate such. Montage-printing When separating their printing plates into several pieces, artists are able to colour them each individually and so to obtain a multi-coloured print, when they are printed together and next to each other.

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3.Komponen etsa logam Etching is where the excess copper is removed to leave the individual tracks or traces as they are sometimes called. Buckets, bubble tanks, and spray machines lots of different ways to etch, but most firms currently use high pressure conveyerised spray equipment. Spray etching is fast, ammoniacal etching solutions when sprayed can etch 55 microns of copper a minute. Less than 40 seconds to etch a standard 1 oz, 35 micron circuit board. 3.1. Substrat ( logam ) Merupakan bahan logam yang menjadi target teknik etsa, tergantung untuk keperluan apa dan fungsi apa, seandainya untuk keperluan teknis maka substrat menggunakan logam yang mempunyai sifat keras misalnya besi dan baja. Apabila hanya sebagai transfer gambar ke bahan yang tidak keras seperti kertas, kulit, imitasi dan lain lain, maka digunakan aluminium. Apabila diinginkan substrat yang mempunyai sifat daya hantar listrik maka menggunakan tembaga adalah pilihan terbaik., Semua logam dapat dietsa sesuai dengan kondisi dan sifatnya, karena mahalnya bahan tembaga saat ini etsa logam untuk kepentingan emboss, hot print menggunakan logam aluminium sebagai pengganti logam subtratnya. Untuk keperluan elektronik masih menggunakan tembaga sebagai bahan substraynya, disamping mempunyai daya hantar listrik dan daya hantar panas yang baik tembaga mempunyai sifat mudah untuk disolder. 3.2. Etchant Merupakan larutan kimia yang bersifat asam atau basa yang mana berfungsi untuk melarutkan logam yang mana efeknya untuk tiap logam berbeda. Etchant tersusun atas beberapa komponen seperti berikut ini agen oksidasi ( FeCl, CuCl, KClO3 ) agen korosi ( HCl, HNO3, H2SO4, H2O2, H2CrO2) agen levelling ( H3PO4 ) agen modifikasi ( ethylen glikol, DEG ) Many different chemical solutions can be used to etch circuit boards. Ranging from slow controlled speed etches used for surface preparation to the faster etches used for etching the tracks. Some are best used in horizontal spray process equipment while others are best used in tanks. Etchents for PTH work have to be selective and be non aggressive to tin / tin lead plating, which is used as the etch resist. Copper etching is normally exothermic, where high speed etching is carried out solution cooling is normally required. This is normally done by placing titanium water cooling coils into the etchent. Almost all etching solutions liberate toxic corrosive fumes, extraction is highly recommended. All etchents are corrosive and toxic, mainly due to the high metal content. P.P.E. Personal Protection Equipment must always be used, spent solutions should always be disposed of properly and not down local drains, where they pollute local sewage works and rivers. For a more detailed chemical look at the etchents please follow the section menu links to the different types of etchent. Ammoniacal Etchent:- Probably the main etchent used within the circuit board industry. Due to it's very smelly nature it is only used in spray etching applications. Normal copper etching reaction is:- Initial reaction, which results in a build up of cuprous ions,

Cu2+ + CuO >> 2Cu+

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Secondary reaction, oxygen is absorbed from the air which re-oxidizes the cuprous ions back to cupric ions,

2Cu+ + 1/2O2 + H2O >> 2Cu2+ + 2OH The basic etching reaction is the same as cupric chloride etching but to work the copper (II) ions require complexing with ammonium chloride and ammonia.

Cu2+ + 2(NH4)Cl + 4NH3 >> 2NH4+ + Cu(NH3)4Cl2

To work free ammonia is present, which always finds it's way past any extraction equipment resulting in strong odors. Ammonia loss results in sludging, as do excess water or excess copper. Its an almost trouble free process when correctly run but can result in hours of machine cleaning if not. Chromic-Sulphuric Acid:- Used to be the preferred etchent for tin tin-lead plated boards but has been replaced by Ammoniacal and Sulfuric Peroxide etchents. Chromic-Sulphuric etchent has only a slow etch rate and low copper holding capacity. The solution is also a serious pollution concern and very expensive to dispose off. Normal copper etching reaction is:-

3Cu + 2HCrO4- + 14H+ >> 3Cu2+ 2Cr3+ + 8H2O

The hydrogen ions are normally provided by Sulphuric acid, beware Hydrochloric acid must not be used as toxic chlorine gas would be liberated. Standard makeup with the addition of sodium sulfate which increases the etch rate is, 240g/l Chromic Acid, 40g/l Sodium Sulfate, 180g/l 96% Sulphuric Acid. Oddly enough air agitation reduces etch rate. Cupric Chloride:- Cheap fast and easy to re-generate, either chemically or by electrolytic recovery. Not suitable for PTH work as it readily attacks tin lead. Normal copper etching reaction is:-

Cu + CuCl2 >> Cu2Cl2

Simple chemical re-generation is possible by adding HCL and enough H2O2 to re oxidize the cuprous chloride to cupric chloride. Excess free peroxide in solution, especially when combined with elevated temperature can result in liberation of toxic fumes. Given time or less time and air agitation the re oxidization will take place without the addition of the peroxide. Ferric Chloride. An old favorite, also very good at staining fingers, clothing, etc brown. Etch rate can be very high but is dependant on solution movement over the surface of the board and temperature. At 70C using Spray etching 1oz copper is removed in a little under a minute, normal etching temperature is more likely to be 45C. When etching circuits if up to 5% of HCL is added it, increases etch rate, helps to stop staining, and reduces the risk of the solution sludging. Ferric especially with extra HCL makes a very good stainless steel etchent. When Ferric crystals are mixed with water some free HCL produced through hydrolysis.

FeCl3 + 3H2O > Fe(OH)3 + 3HCL

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The basic etching reaction takes place in 3 stages. First the ferric ion oxidizes copper to cuprous chloride, which is then further oxidized to cupric chloride.

FeCl3 + Cu > FeCl2 + CuCl FeCl3 + CuCl > FeCl2 + CuCl2

As the cupric chloride builds up at further reaction takes place, CuCl2 + Cu > 2CuCl

The etch rate quickly falls off after about 17oz/gallon (100g/l of copper has been etched. For a typical solution containing 5.3lb/gallon (530g/l) of ferric chloride. Nitric Acid:- Not the safest of chemicals but a simple fast etchent. Often used as a quick fix for removing any remaining copper from a electroless copper tank prior to use. Adding by weight 2% of Potassium chlorate to a 10% Nitric Acid solution allows it to etch brass. Normal reaction as a copper etchent is:-

3Cu + 2NO3- + 4H+ >> 3Cu2+ + 2NO2 + 2H2O

Persulfate Etches:- Sodium, Ammonium, Potassium Persulfates all make good copper etches. They can even have catalysts added which then allow them to be used with tin tin-lead resists. When the salts are dissolved in water the Persulfate ion is formed, which then goes on to oxidize copper to the cupric ion. Std Reaction is :-

Cu +(NH4)2S2O8 >> CuSO4 + (NH4)2S2O4

Std makeup is 100-200g/l of Persulfate salt, 20ml/l 96% Sulphuric Acid. A mixed solution becomes exhausted in 3-5 days independent of usage. Hydrochloric acid must not be used as toxic chlorine gas would be liberated. Once done the use of the wrong acid is never repeated. This etch is commonly used as a micro etch (chemical sandpaper) before plating processes. Sulphuric-Peroxide Etches:- Cheap, easily recoverable etch used for etching PTH circuit boards, also used as a micro etch (chemical sandpaper) before plating processes. A straight mixture of Sulphuric and Peroxide makes a very fast etchent, but sadly is unstable and not safe to use. Additives are added such as Aryl Sulfonic acids to stabilize the peroxide in solution, and even Phosphoric acid which helps to retain a cleaner tin lead over the copper. Std Reaction is :-

Cu + H2O2 + H2SO4 >> Cu2SO4 + 2H2O

Copper can be recovered as copper sulphate by cooling and crystallization, or as metallic copper by electroplating. This is often done by plating onto stainless steel plates using lead or graphite anodes. After which the copper can be easily peeled off the stainless steel plates 3.3. Resist Merupakan bahan penutup substrat ( logam ) yang akan diproses dengan larutan etsa. Resist merupakan bahan kimia polimer tahan asam, dapat berasal dari polimer sintetis

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atau alam. Polimer alam atau resin antara lain kopal, sirlak, gum, dammar, aspalt powder, Sedangkan polimer sintetis yang dapat digunakan untuk bahan resis adalah; PVC, Acrylik, epoxy, nitroselulose dan lainnya. Solder resist is the usually green lacquer like coating which covers the major part of most modern circuit boards. It is specifically designed to both protect the surface tracks and prevent solder bridges during soldering. The surface often has traces of silicones or similar to promote these properties, which can occasionally lead to strange effects and deformations in the Comp Ref. layer when it is screened on top. All the types of Solder Resists used as best regarded as permanent and non removable. Although our tests have shown that quite a few of the normal production Resists are lacking strength to resist the new low clean fluxes. we are told that is due to the higher level of solids in the older fluxes, which used to provide some form of protection for Resist. Although the standard colours are green, red, blue, and black should you be after a unique colour we are always happy to oblige by mixing the resists. Results are a little unpredictable, but be guaranteed the outcome will be a unique colour! Two Pack Epoxy Solder Resist:- This is the standard type of solder resist we use. Being a thermally cured ink it is possible to have a very high level of pigmentation resulting in its easily distinguishable richer colour. Nick named Two Pack from the two components namely, Resin and Catalyst from which a working mix is made. To enable the best protection ink is used very thick and screened with a course silk screen mesh. This has the combined effect of increasing the thickness of the Resist layer. The main drawback with this type of Solder Resist is that it takes over a hour at 120C to fully cure. Can be used down to 6 thou clearance but to avoid problems more in the order of 12 to 15 thou is advised. With a tight clearance you risk bleeding of solder resist onto the pads. U.V. Solder Masks Traditionally used in high volume production especially on the cheaper punch and crunch phenolic paper laminates. The ink is very similar to Two Pack and is screened in much the same way. The big difference is that this ink can be quickly cured using ultra violet light [On a std UV curer the conveyer runs between 3-6m/min ]. Its for this reason that the pigmentation level tends to be lower. For the simple reason that the darker the ink the harder it is for the light to penetrate and cure the ink. Dry Film:- Not as common as it used to be. This type of resist is applied using a special high pressure laminator. After which it then requires the resist pattern exposing, followed by development and then hardening by either thermal baking or a quick passage through an infra red conveyer. Greatly replaced by the improvements made in the photo imageable ink systems.

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Photo Imageable Solder Mask:- With the ever increasing drive towards miniaturisation the traditional wet screened resists couldn't provide the definition required. Photo imageable inks are fast becoming the most widely used type of solder mask. This range of inks can be coated in a few different ways, curtain coating, screening, and electrostatic spraying. Curtain coating is done on a machine in which the boards are fed on a conveyor through a Niagara Falls of the ink. Electrostatic spraying is like normal pain spraying, but a high voltage charge exists between the spray gun and panel. In all cases the solder resist pattern is then transferred by aligning a photographic master and exposing using U.V. The panels then require developing in a mild alkali solution followed by high temperature baking. More expensive than the two pack epoxy inks but very high definition. Photo-Imageable S/R masks can have zero clearance, and are available in a large range of colours. Oddly enough these colours include black, which to date has always worked without incident. Quite how the UV successfully polymerizes through the black ink is a mystery, obviously it's time to re write rules and laws of science. Peelable Resist Best described as a thick normally blue plastic covering which is resistant to soldering processes. It's designed to tent over component or mounting holes and prevent them from filling with solder during wave soldering. Another use is as an alternative to masking tape in order to protect edge connectors. The ink in the tin before use closely resembles window putty, and also requires a special silk screen covered with a very course mesh. Once applied it only takes an odd minute of baking to turn it into its solid dry form. Please note that on conventional non PTH circuits by either taking a small section out of a pad or creating a solder relief area using ink, it is possible to reduce the number of holes that fill with solder. The removed or covered section optimum shape is best described as a Packman mouth which is almost closed. 3.4. Container Merupakan tempat atau wadah yang digunakan untuk proses pengetsaan logam. Biasanya terbuat dari bahan yang tahan terhadap larutan asam atau basa. Plastik polipropliten, polivinyl clorida, gelas kaca adalah bahan yang tahan terhadap larutan etsa. 3.5. Safety equipment Peralatan untuk keamanan pada saat melakukan proses pengetsaan, sarung tangan tangan asam, kaca mata, kamar asam.

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4. Prosedur pengetsaan Etsa merupakan seni grafis kimia yang sudah sejak lama ada, zaman dulu digunakan untuk menandai peralatan kerajaan, peralatan militer, barang hak milik. Sekarang teknik etsa sudah sangat berkembang, peralatan IT sangat mendukung untuk kemudahan dalam pembuatan desain hingga prosedur etsa kimia itu sendiri.

a. Pembuatan desain grafis. Membuat gambar pola menggunakan komputer

Mencetak gambar pola menggunakan printer laser

Membuat film gambar pola diatas screen

Menyablon gambar pola diatas logam (substrat)

b. Persiapan larutan etsa Penimbangan bahan kimia Pencampuran bahan kimia dengan air dalam wadah (kontainer) tahan asam Larutan sudah siap digunakan Penggunaan larutan dalam jumlah pengerjaan tertentu mengharuskan

penggantian larutan yang baru.

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1. Etsa Kuningan dan Tembaga Formula : Air 6-7 bagian HCL 1 bagian H2O2 1 bagian

Resist: - Tinta sablon - Stiker - Cat - Lakban / isolasi (paling kuat tapi sulit dalam pembuatan motif) Proses Kerja Etsa 1. masukkan seluruh bahan etsa pada sebuah wadah plastik tahan kimia secara

berurutan dari air lalu HCL kemudian H2O2 secara hati-hati, lalu aduk hingga rata.

2. masukkan tembaga atau kuningan yang sudah di resist ke dalam larutan, amatilah sampai terlihat reaksi kimianya dan goyang-goyangkanlah agar tidak terjadi endapan kotoran pada daerah etsa. Lakukanlah hingga mencapai kedalaman yang diinginkan.

3. jika sudah memperoleh kedalaman yang sesuai, ambillah kuningan atau tembaga tersebut dengan penjepit plastik tahan kimia.

4. basuh dan bersihkan kuningan atau tembaga tersebut dengan air 5. lepaskan resist yang masih menempel hingga bersih.

Perhatian: • Jauhkan bahan kimia dan tempat proses kerja dari jangkauan anak-anak • Jika kena kulit segara bilas dengan air, jika kena mata bilas dengan air dan

segera bawa ke dokter. • Selalu gunakan masker,kaca mata, sepatu dan kaus tangan plastik tahan kimia

2. Besi dan Stainless Steel Formula 1 : Air 1 lt FeCl3 196 gr / lt H3PO4 71 % HCL 6 % EG 23 % Resist: - Tinta sablon - Stiker - Cat - Lakban / isolasi (paling kuat tapi sulit dalam pembuatan motif)

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Proses Kerja Etsa 1. masukkan seluruh bahan etsa pada sebuah wadah plastik tahan kimia secara

berurutan dari Air, FeCl3, H3PO4, HCL, EG secara hati-hati, lalu aduk hingga rata.

2. masukkan besi atau stainless steel yang sudah di resist ke dalam larutan, amatilah sampai terlihat reaksi kimianya dan goyang-goyangkanlah agar tidak terjadi endapan kotoran pada daerah etsa. Lakukanlah hingga mencapai kedalaman yang diinginkan.

3. jika sudah memperoleh kedalaman yang sesuai, ambillah besi atau stainless steel tersebut dengan penjepit plastik tahan kimia.

4. basuh dan bersihkan besi atau stainless steel tersebut dengan air 5. lepaskan resist yang masih menempel hingga bersih.

* resist bertahan agak lama, tapi proses etsa agak lambat

Formula 2 : Air 4-5 bagian HCL 1 bagian H2O2 1 bagian Resist: - Tinta sablon - Stiker - Cat - Lakban / isolasi (paling kuat tapi sulit dalam pembuatan motif) Proses Kerja Etsa 1. masukkan seluruh bahan etsa pada sebuah wadah plastik tahan kimia secara

berurutan dari Air, HCL, H2O2 2. secara hati-hati, lalu aduk hingga rata. 3. masukkan besi atau stainless steel yang sudah di resist ke dalam larutan,

amatilah sampai terlihat reaksi kimianya dan goyang-goyangkanlah agar tidak terjadi endapan kotoran pada daerah etsa. Lakukanlah hingga mencapai kedalaman yang diinginkan.

4. jika sudah memperoleh kedalaman yang sesuai, ambillah besi atau stainless steel tersebut dengan penjepit plastik tahan kimia.

5. basuh dan bersihkan besi atau stainless steel tersebut dengan air 6. lepaskan resist yang masih menempel hingga bersih.

* resist cepat terkelupas, tapi proses etsa cukup cepat.

Perhatian:

• Jauhkan bahan kimia dan tempat proses kerja dari jangkauan anak-anak • Jika kena kulit segara bilas dengan air, jika kena mata bilas dengan air dan

segera bawa ke dokter. • Selalu gunakan masker,kaca mata, sepatu dan kaus tangan plastik tahan kimia

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3. Alumunium Formula 1 : Air 5 bagian HNO3 2 bagian HF 2 bagian Resist: - Tinta sablon - Stiker - Cat - Lakban / isolasi (paling kuat tapi sulit dalam pembuatan motif) Proses Kerja Etsa 1. masukkan seluruh bahan etsa pada sebuah wadah plastik tahan kimia secara

berurutan dari Air, HNO3, HF secara hati-hati, lalu aduk hingga rata. 2. masukkan alumunium yang sudah di resist ke dalam larutan, amatilah sampai

terlihat reaksi kimianya dan goyang-goyangkanlah agar tidak terjadi endapan kotoran pada daerah etsa. Lakukanlah hingga mencapai kedalaman yang diinginkan.

3. jika sudah memperoleh kedalaman yang sesuai, ambillah alumunium tersebut dengan penjepit plastik tahan kimia.

4. basuh dan bersihkan alumunium tersebut dengan air 5. lepaskan resist yang masih menempel hingga bersih.

* resist bertahan lama hanya lakban dan aspal, dan proses etsa agak lama.

Perhatian:

• Jauhkan bahan kimia dan tempat proses kerja dari jangkauan anak-anak • Jika kena kulit segara bilas dengan air, jika kena mata bilas dengan air dan

segera bawa ke dokter. • Selalu gunakan masker,kaca mata,sepatu dan kaus tangan plastik tahan kimia

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5.How to make a printed circuit board.

I occasionally make small simple single sided printed circuit boards and thought it might

be helpful if I put down some of the things I have learnt.Firstly the manual method.

Gather your components so you have their dimensions then on some 1/10 inch graph

paper draw their positions and the tracks that are needed pretending you are looking

down on the component side of the board. You can print out your own graph paper using

free software (see my software page). You will find that most component leads fall on a

1/10 inch grid. If the pins on your components are closer than 1/10 inch you may find that

the process of drawing the tracks later on the actual PCB is difficult. Now fix the paper to

the component side of the board and mark each component lead hole by using a sharp

point. To drill the holes you will need .8mm or 1mm drill bits for most components.

Now you need to draw the tracks and you have the holes to guide you but your paper

layout is the reverse of what you will see when you are looking at the copper side of the

board. My solution is to sit near a window and stick the paper on it so that I can see

through it. Clean the board with a plastic scourer and detergent, a slightly rough surface

helps the resist to flow neatly. To make the tracks you can use a resist pen from an

electronics hobby store or you can try a mapping pen with some tar dissolved in

turpentine. I actually had a lump of tar that I used for 20 years but when it took a hike I

substituted it with some tar type roofing paint.Some other things to try:-

Buy some pre-punched board (1/10 inch perf board) and stick the components in it to to

help with judging the spacing and layout. This is what I usually do and it is why I do

most layouts looking from the component side.Print out the graph grid on some stout

tracing paper that you can usually buy in pads. You will be able to see through it when

you mark the copper side of the board and have a proper picture to follow when making

the tracks.The small surface mount device above required tracks thinner than I could

make manually but I got around the problem by hand making a board and using fine wire

for the final connections.The software and photo-resist method.The information below is

a report of what I have found works with the products I have available. If you deviate

from the suppliers recommendations that apply to any product it is your responsibility.

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The problem I had with the size of the above surface mount device prompted me to look

for a better way and I found it.I located some PCB pre-coated with positive photo-resist

from Dick Smith Electronics. The only clue that I have to the manufacturer is an "L" on

the board. I also purchased some KINSTEN branded board from

www.computronics.com.au it looks the same and it came with comprehensive

instructions. I also found a software programme that was free for non commercial use up

to a 200 pin number limit.Layo1 PCB from www.baas.nl is easy to use and can print

directly to your windows printer or to commercial board making equipment. I used it for

all the boards and layout pictures on this site. If you intend to draw the tracks by hand it

is still a good option to use software as it bypasses the graph paper stage. Layo 1 PCB

can handle many layers but you can turn off the layers you do not need and only print the

bottom copper layer. One hint is to make the minimum hole size to about .8mm. You do

not need the correct hole size on the print out because you will be drilling the holes your

self but if you adjust the size correctly then you will find the etched hole makes starting

the drill so much easier, too big and the drill drifts off centre and too small and they may

not etch. The software will also make any text you add mirrored as you view it from the

parts side so it will etch correctly.

Making the transparency

Watch out for options that change the size and quality of the printout as there are heaps of

them in PDF and laser printers, then do some experiments. If you have a laser printer you

can print on the special laser printer film for over head projectors. There is a common but

minor problem with pin holes as can be seen below.As you will be using a full page of

the film each time you should fit as many copies of your circuit as you can on the one

page while you are in the PCB software. Check the print out with a magnifying glass and

select the best result.With an ink-jet you can print on special ink-jet transparency film.

You may get a shock when you see the price so it pays to read the internet regarding the

best brand to use and to cut the sheets up. I print out on scrap paper first then attach the

film over the printout using the sticky part that I cut from post-it type notes. The only

media setting that I find satisfactory on my old Canon BJC-2000SP is "Fabric printing".

the best mode is "Graphics" . The "Fabric" setting really loads the film with ink, note

how it builds up.

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Any other setting on my printer results in the above result. Note that ink-jet transparency

film I used had some problems. It was dirty when I got it and it picked up lint etc. as it

was a little sticky. It tends to bleed ink away from the tracks over a period of some days

and this causes the holes to fill up. This bleeding problem does not occur with photo

gloss paper and I can not see why the same technology could not be used with a clear

backing for transparency film --perhaps it is on better brands.

You can also use an ink-jet with tracing paper. This is thick and translucent and it can be

bought in sheets or pads. The advantage is price and the ink will not bleed over time but

the tracks are not quite as clean and the fibres can be seen sometimes as clear in the

tracks.

The photo resist PCB is very forgiving and just as an experiment I made a board for the

above surface mount chip using a 90 g/m2 ( as thin as I could find at

www.inkme.com.au---) high resolution single sided coated paper printed using "standard

paper" printer settings

The above shows the difference between a good coated and a standard paper. With the

coated paper the result is limited by my old Canon BJC-2000SP and its 720V X 360H

resolution. With standard paper the result is limited mostly by the fibres in the paper.

I smeared the printout with cooking oil to make it transparent and blotted it dry. A board

exposed for 20 minutes, then given a spray with detergent and a rinse to completely

remove residual oil before developing gave excellent results and faithfully reproduced the

faults made by my old printer including the occasional almost invisible gap in a track.

Without the oil the board required 80 minutes of exposure.

Perhaps if I substituted artists linseed oil or some thinned varnish for the cooking oil it

would eventually set and give a permanent transparent result. A problem might be the

paper buckling when the oil sets and thus not remaining flat on the board during

exposure. This buckling problem would mainly affect larger boards and can also show up

with laser printer film if the heat used to fuse the toner in the printer buckles the film.

Basically I think you could use any paper that gives a good pattern and can be made

transparent with oil including light weight photo papers with no plastic backing. I tested a

sample described as "Mirror finished coated paper for 1440 dpi. 140gms Best seller, gloss

photo like finish" and it worked with a 25 minute exposure after oiling.

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With coated or photo paper you may find it easier to get good artwork but the residual oil

is a problem. Why not give it a try if you already have some on hand.

EXPOSING THE BOARD

It was a revelation when I found out that modern resist coatings could be exposed with a

normal fluorescent or low cost compact fluorescent tubes. This means almost anybody

can lash up some method of exposing a board. My fish tank light a sheet of glass from a

photo frame and the kitchen timer is all I need. With the board 55mm from the tube

exposure takes about 11 minutes with film and 13 minutes with tracing paper. I let the

light warm up for a couple of minutes then slide in the assembled stack on a sheet of

paper. You should have the printed side against the resist and you should be able to read

any lettering correctly through the film.A compact fluorescent and an old desk lamp will

also do the job.

DEVELOPMENT AND ETCHING

Development takes about 70-100 seconds in an agitated solution of 1 level teaspoon

(5ml) of caustic soda beads dissolved in 750ml water. Do not try to skimp by making up

some smaller quantity as measuring less than 5 ml is too inaccurate. It is fortunate that

caustic soda works with the board I use as it is available at supermarkets at low cost but

be aware that caustic soda is dangerous stuff so read and follow the precautions on the

package. I drill a hole in the board and loop some string through and etch in a ferric

chloride solution giggling the string occasionally.I then wash and dry the board then re-

expose it and re-develop it. This exposes and washes away the coating on the tracks.

DRILLING

I used to drill boards with a hand drill and have done some small ones with a pin chuck

and fingers. I now use a small rechargeable drill chucked onto the pin chuck. The only

special drills that I have needed are .8mm and 1mm that I get from a hobby electronics

shop.Above I am getting the last out of a broken drill. I hope the above encourages you to

have a go at making a simple PCB.

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