The process of screen printing with screen printing and sandblasting is a traditional sign making process. This kind of product is silver white outside, the surface hardness is high, and the wear resistance is good. The process flow is as follows:
Screen printing, printing and blanking and prepress processing, screen printing, etching, piercing, anti corrosion, bright, sand blasting, chemical polishing, anodization, sealing, painting, punching, and finishing.
Preconditioning
A, bearing material: aluminum is usually semi - hard industrial pure aluminum, such as L1Y, L2Y2 and so on.
B. aluminum plate pre treatment: including mechanical polishing (or wiping machine, then brush machine brush) and alkaline solution deoiling.
After the aluminum plate is deoiling, it is washed in the water and stored in the water tank to be coated with photosensitive glue. Sometimes, in order to make the photosensitive glue adsorbed on the aluminum plate well, after removing the oil, we need to use water brush to touch the calcium carbonate powder (also called the double fly powder and the old powder), wash the aluminum plate by hand or machine, then wash it to be ready for use. After the aluminum plate is pretreated, the plug is dried to be dried to be printed.
Photochemical plate. Plate signs light chemical, refers to ultraviolet light through the film image, produce photochemical reaction, the surface of aluminum coating photographic film is developed, fixed film processing, the process of forming a resist film pattern Jiao.
Photogelatin generally consists of bone glue, gelatin, shellac, protein and polyvinyl alcohol film forming agent, and water as the solvent or ethanol after cooking, withered with adding amount of ammonium dichromate, photosensitizer, when necessary, appropriate to add some ammonia, twelve sodium, two dimethyl sulfoxide additives and etc..
Polyvinyl alcohol photoreceptor is used to protect the corrosion resistance of the graphic.
Photosensitive adhesive with good for spreading, dipping, spraying or glue coating method is evenly coated on the aluminum surface, dry heating in infrared light, and film stacked folder on the printer, using high pressure mercury lamp, lamp, xenon lamp exposure picks, iodine gallium lamp, carbon lamp or special UV light after remove the water, wash away the unexposed part of the film, and then immersed in 5 of rhyme about methyl violet in aqueous solution (protein emulsion by developing the inking method, some developing) can also be chemical solid membrane in chemical solution in particular, finally into the incubator.~140 250~ (constant temperature baking, about 2 of the surface to be baked brown can be taken out, after appropriate repair, back painted shellac or pink (mixture of rosin, ferric oxide and high fatty acids, etc.) can be corrosion after drying.
Now, photochemical plate can also directly paste the tartaric water-soluble photoresist dry film on the surface of the pretreated aluminum sheet with film machine. After UV exposure, it will be developed in 1 to 2gbNa2CO3 aqueous solution and fully cleaned and dried after developing, so that it will corrode.