Signage screen printing technology question and answer (19-29)

19. How to make a plate printing plate plate?
A: The production of signage panel screen printing plate is mainly considered to solve the problem of the neat edge of the word line, and the following points should be noted.
1. The quality of the film is better, the edges of the word lines are neat, the darker the black areas, the more transparent the better.
2. Use mesh with high mesh number and filament diameter, commonly used 300T, 350T, 420S polyester mesh.
3. Select a high-resolution diazo photosensitive or capillary photosensitive film.
4. Control the thickness of the photoresist, generally about 10 ~ 12μm is better. If there is no thickness gauge, the film thickness can be judged by watching the color depth or whether the printed surface film reflects light.
5. To expose the feet, rinse thoroughly.
6. The small-character thin line should adopt a 22.5° angle or a 45° angle, which is beneficial to the neatness of the word line edge.
7. Platemaking room and utensils should be clean.

20. What are the methods for making etching resists for etching signs?
A: 1 using glue and ammonium dichromate solution made of photosensitive adhesive coated on a metal plate, after printing, development, coloring, drying, and then baked, so that the adhesive layer was chestnut skin color, you can Etch the sign's resist layer.
(2) The photosensitive dry film produced by the circuit board is heated and attached to the metal plate, and then subjected to the printing plate and the development can be used as the etching resist of the etching plate.
3 It can be directly used as etching resist for etching signs by using computer lettering and stickers on metal plates.
(4) Print the resist ink on the metal plate with a screen printing method to form a text pattern. After drying, the resist layer can be etched.
(5) Using screen printing method, the photosensitive circuit board printing ink is printed on the metal plate, the printing is a large field, and after drying, the printing plate can be used as a resist film for etching signs.

21. What are the etching methods?
Answer: 1 manual etching includes brushing, splashing, shaking and so on. The etch is to brush the solution back and forth on the metal plate with a row of pens. The splash is to use a spoon to continuously spray the solution onto the surface of the metal plate for etching. The shaker is to make a plastic groove under the arc, put the etching solution, put into the metal plate, manually press the side of the groove, so that the etching liquid on the metal plate flows back and forth.
(2) Etching the water wheel impeller with a sputter etching machine, and continuously etching the etching liquid onto the metal plate for etching.
3 Etching with a stir-etcher A vertical shaft with a blade is placed in the middle of a large porcelain jar to make a mixer. The etching solution is constantly stirred and the metal plate is placed on the edge of the cylinder for etching.
4 Etching with a spray etcher Spray the etchant from above with several water jets. Place the metal plate on the conveyor belt below to move forward. Control the speed. After it has been removed, it is etched.
5 etching with an electrolytic etching machine The metal plate to be etched is connected to the positive pole of the power source. After laying flat, the shower device is connected to the negative pole of the power source, and the sprayed salt water is the conductive liquid for electrolysis to achieve the purpose of etching.

22. What are the commonly used etching solutions?
1 etching aluminum plate ferric chloride liquid Baume degree 36 ~ 42, 3 parts copper sulfate Baume degree is 16, 7 copies of the two mixed with water transferred to Baume degree 16 ~ 18.
2 brass plate ferric chloride Baume degrees 36 ~ 38
3 stainless steel plate
(a) FeCl3 38-42
(b) Copper chloride 200 g/L hydrochloric acid 200 mL/L
(regenerated with hydrogen peroxide)
4 titanium plate electrolytic etching (brine electrolyte)
Or remove the titanium gold by etching the stainless steel chemical etching method.
The new formula can refer to the 4th issue of Screen Printing in 1996 and the Practical Guide to Screen Printing.

23. What is Baume degree?
A: There is a certain relationship between the concentration and the specific gravity of the solution. The method of checking the concentration of the specific amount of the solution in the production is easy to use with the Baume weightmeter. Baume was invented by a French chemist. The Baume table weights the table and the light table two kinds. Heavy gauges are used for the measurement of solutions heavier than water, and light gauges are used for the determination of lighter organic solvents. Baume watches are available at glassware stores.

24. What kind of paint is used for etching signs?
Answer: The background color of the Braille aluminum plate is sprayed with nitro lacquer. The surface of the sign is sprayed with nitrocellulose varnish.
Aluminium oxide varnish panels are filled with alkyd enamel paint. Concave big copper brand paint with alkyd enamel paint. Bronze sprayed amino clear baking varnish, also used acrylic clearing paint.

25. What's new in the etching sign?
A: Etching signage is an old process, but it also has a new level due to the adoption of new technologies. Here are some common ones.
1 The surface of the metal plate is processed into a silk grain or a fine sand surface, so that the appearance is better.
2 Using a resist layer on the metal plate to form a text pattern, then electroplating other color metals. There are similar stereoscopic etch.
3Using imitation etching ink, printed on the titanium plate, bright stainless steel plate, gold and silver cardboard, and got the sign of etching effect.
4 Use a computer to engrave the two-color plate, such as a black plastic layer below the golden surface layer. The gold layer is engraved to form a text graphic, exposing the black bottom and the frame, without having to be etched, without having to fill the lacquer and spray the surface protective paint, and instead of the etching process, the sign can be made.
5 Use computer to engrave stickers and paste them on titanium plate. The text graphics part is sandblasted to remove the titanium layer and form a sand surface. There is also an etching sign effect.
6 Newly developed electrolytic etching process works well.
7 Newly developed chemical etching solution for environmental protection.

26. What are the characteristics and uses of aluminum oxidation signage?
A: The main features of aluminum oxidation signs are light, wear resistance and corrosion resistance. Mainly used in machine tool signs, sports device signs, advanced makeup boxes, ballpoint pen caps and so on.

27. What equipment is needed to make aluminum oxidation sign?
A: Aluminum plate pretreatment equipment: polishing machine, sandblasting machine, brushing machine, degreasing cleaning machine.
Aluminum oxidation equipment: chemical polishing, electrolytic polishing equipment, silicon rectifiers, oxidation tanks for plastics or porcelain, cooling equipment (freezers and lead tubes), compressed air mixing equipment, and exhaust equipment.
Aluminum oxide post-processing equipment: dyeing tanks, sealing equipment, screen printing equipment, etching equipment, three waste treatment equipment.
Other equipment: cutting machine, punching machine, molding and stamping equipment.

28. At present, which methods are commonly used to produce aluminum oxidation signs?
A: There are various methods for producing aluminum oxidation signs. The commonly used methods are secondary oxidation and combination processes.
Examples are as follows:
Secondary Oxidation: Slicing → Mechanical Polishing → Chemical or Electrochemical Polishing → Anodizing → Coloring → Sealing → Screen Printing Text, Graphics → Film Stripping (Oxide Film) → Second Oxidation → Coloring → Sealing → Mechanical Polishing → Cutting and stamping.
Combined process method: slicing → brushing → oxidation → gold → spray lacquer → chromatic offset printing → spray protection lacquer → protective film → cutting and stamping → convex high light cutting.
There are many methods for combination, which can be combined with screen printing, offset printing, electrophoretic paint, high-light cutting, etching, sandblasting, and brushing.

29. Aluminium Oxidation What are the oxidation methods for making signs and panels?
A: There are several ways to oxidize aluminum plate and panel:
1. AC oxidation coloring, oxide film soft for stamping embossing post processing;
2. Room temperature sulphuric acid oxidation is suitable for black dyeing;
3. Low-temperature sulfuric acid oxidation, fine and hard oxide film, suitable for printing ink, gold dyes, etc.;
4. H2SO4, oxalic acid mixed acid oxidation hard oxide film can be obtained under normal temperature conditions;
5. Porcelain oxidation is anodized with chromic acid and boric acid, with the same surface glaze.