Screen printing methods and requirements for special products (2)

Fourth, stainless steel products silk screen

There are many methods of processing on stainless steel surfaces, which can be roughly divided into two types. One is to treat stainless steel with surface gloss, and to use art processing to form a pattern using luster contrast; the other is to assign color to the composition of patterns. Art processing. Typical examples of the use of the screen printing method include etching and spray painting.

Etching processing method is to screen the acid-proof protective film on the stainless steel surface by screen printing, and then etch it with ferrous chloride solution to form an artistic pattern. The spray color method sprays pigment particles after screen printing to form a pear-like surface and form an artistic pattern.

In recent years, in order to adapt to the diversification of the use of stainless steel and higher and higher artistic requirements, the “color art” processing method with color has been developed and has become the mainstream in this field. Among the methods for imparting the color of stainless steel include a method of performing firing after screen ink printing and a chemical coloring method.

The process of chemical coloring of stainless steel products is: stainless steel products → screen printing → oxidation coloring → alkali treatment → Finished Products.

The etching art process of stainless steel products is: stainless steel products → silk screen → etching → alkali treatment → oxidation coloring → finished products.

The process of spray painting of stainless steel products is: stainless steel products → silk screen → etching → alkali treatment → screen printing → oxidation coloring → alkali treatment → finished products.

The stainless steel chemical coloring method does not use pigments and dyes, but soaks the stainless steel in a warm concentrated chromium sulfate solution to perform chemical coloring, which is characterized by good resistance to food. The ink used in this processing method must have a very strong acid resistance, and UV curing inks having special properties suitable for the processing process are generally used.

Fifth, the silk screen of the light reflector

The light reflector is a kind of silk screen that is irradiated by the headlights or other lights of a car and the light is reflected by the irradiated object in the direction of the light source without being affected by the angle of irradiation or the weather. Reflective is a hollow glass particle with a diameter of about 40 μm, with a reflective layer at the other heart. Its flexible sheet-like support has an adhesive layer and a release layer on its surface. A reflection layer is generally provided on an acrylic resin plate, and a reflection layer is formed by adding a certain amount of hollow glass particles with a transparent resin and printing by a screen printing method. When printing, we must carefully select the mesh number, hole width (opening degree), and the type of hollow glass particles. The hollow glass particles are regularly arranged.

This type of printing is used for various signs, commercials, etc. so that it can be confirmed in dark places. In addition, printing for road signs, air navigation signs, lifesaving appliances, security helmets, etc. can also be considered.

Six, with silk screen printing transfer aluminum

Gorgeous and beautiful, bright aluminum color hot stamping through the hot stamping machine, on the substrate, its beautiful color has won wide appreciation. However, sometimes the bronzing machine will also encounter products that are not suitable for mechanical bronzing. However, the customers are stubbornly not using screen printing gold. In the dilemma, the unique screen printing plate transfer galvanized aluminum shows its superiority. Hot stamping machine is mainly based on the temperature and pressure of the electro-aluminum stamping, and the screen-printed electro-aluminum is dependent on the role of the adhesive. The reason why adhesives can transfer anodized aluminum is because the outermost layer of anodized aluminum consists of a glue layer.

In the electro-aluminum transfer printing operation, the printed text must first be made into a screen plate, and the graphic requirements on the plate are clear. Then use a silk screen plate to print a layer of adhesive on the substrate, and then put the aluminum foil on it, and then use cotton or sponge to lightly press in the graphic area, wait until dry, tear off the anodized aluminum (strongly sticky Dry, torn off faster, there is a clear and bright picture of anodized aluminum.

Adhesive formulation is the key to transfer. The formulation shall be formulated as appropriate according to the nature of the printed material, the nature of the anodized aluminum layer, and the suitability of the screen plate. The formulation's viscosity and concentration should be properly formulated. For example, in the case of transfer cloths and polyvinyl chloride, polystyrene plastic products and wood products, the adhesive formulation is:

Perchloroethylene resin 100g

Xylene 50ml

Cyclohexanone 350ml

Perchloroethylene resins can also be used instead of or in combination with polyvinyl chloride resins. PVC resin with low molecular weight. When transclamming plastic products, xylene can be replaced with acetone in the above adhesive formulation. When transferring plexiglass products, some chloroform may be added. When transferring metals, ceramics, and glass products, the adhesive formulation is: 100% epoxy resin. (Ortho) dibutyl benzoate 3% to 5%, ethylenediamine 12% to 15% (concentration too high can add thinner).

Seven, silk screen prints

In recent years, silk screen printing has been promoted and popularized in China, and many high-level works have appeared. The artistic level of screen printing is close to woodcut prints, but the production of screen printing is much simpler than the production of woodcut prints. In addition to the commonly used paper, silk screen printing substrates include cloth, plexiglass, wood, porcelain, and metal plates. This has broadened the road for the development of practical use of silk screen printing, such as the production of posters, decorative paintings, clothing, headscarves and the like in the form of screen printing. The printmaker can fully design and produce practical art and improve its artistic level. Wall hangings, screens, curtains, sofa covers, cushions, etc. are areas in which screen printing prints can play a role. On the one hand, pure artistic prints are produced. On the one hand, it is of great significance to open up positions for prints in practical art and to play a role in beautifying people's lives.

Eight, lacquer silk screen

Silk screen printing has been introduced into the traditional industry. One of them is the lacquerware industry. Representative lacquerware products such as bowls, drawers, boxes, etc. can also be adapted to modern lifestyles. Nowadays, lacquerware products have been developed to meet various purposes. The implementation of a variety of printing methods has increased the value of the product. Among these decorative methods, the more commonly used is silk screen printing of gold powder and silver powder on lacquerware.

1. Screen printing and lacquer slush technology. Lacquerware lacquer technology is to apply black paint and lacquer on wood and plastic substrates first, then draw a pattern on the surface with lacquer, and then apply gold and silver before the paint is dried and hardened. Painted, polished gold paint.

Mud process, when printing with screen, there are two kinds of manual and automatic, generally based on manual. The first step of the slush is to make the printing plate of the design pattern. In screen printing, this process belongs to plate making, so it is omitted. The following is a description in order.

2. Printing Equipment. Plane printing equipment for pots, drawers, and boxes. First place the plate on the stage, then place the lacquerware on the stage and position it, and fix the lacquerware after positioning. In mass printing, there must be a positioning and fixing device (for example, a convex wooden table in which the substrate can be inserted), and the gap between the layout and the printing surface is 1 to 2 mm. The surface printing of cans and bowl substrates is centered on a circular screen plate. The blade is down and the substrate runs upwards. When the scraper, screen and substrate come into contact, the rotary force of the screen plate presses the blade to make printing. Rotate and print.

3. Modulation of printing lacquer. Here is just a brief introduction to the paint method. The paint itself cannot be used as an ink. The viscosity of the paint is low, air bubbles are easily mixed in, and the printing surface is blistering, failing to meet precise printing requirements. Therefore, to make the paint reach a good ink state, it needs to be modulated. Compared with other coatings, the drying conditions of paints are completely different and they are dried by oxidation. Therefore, it is necessary to control the temperature and humidity. Viscosity adjustment of printing lacquer: mix ferric oxide, titanium oxide, protein, anhydrous silicic acid, etc. with lacquer, mix thoroughly, and seal it for 4 to 5 days. The viscosity can be adjusted to approximately 500 poise. It can be used for printing. Ink.

4. Drying and puddle time of paint (ink). The drying of the paint is greatly affected by temperature and humidity. The optimum drying temperature is 30 to 35°C and the humidity is 75% to 80%. The time of puddle is directly proportional to the drying time. The greater the viscosity of the paint (ink), the faster the drying.

5. The precision of printing. Adjusting the lacquer of the paint (ink) to 65% or more or 40% or less is not preferable as a printing condition. That is, a lot of liquid paint, off the bad, leaving traces of paint. Especially on the surface of the substrate, it can be clearly seen in the direction of printing. In addition, when the amount of paint is low, the flowability of the paint is poor, the surface of the printed pattern is unstable, and traces of the screen are left, especially when gold or silver powder is printed. Screen-making screens generally use nylon meshes of 250 to 300 meshes, and have good precision. Because the paint requires special drying conditions, it is not easy to cause screen hole blocking phenomenon, and the printing operation is good.