The hottest screen printing technology decorates f

Silk printing technology decorates flat glass

according to the principle of silk printing, ink is printed on the surface of flat glass, and then ink curing measures are adopted to make the pattern firm and durable. The process is as follows: stretching → sizing → drying → plate printing → developing → drying

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flat glass → cutting → edging → cleaning and drying → printing

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sintering

suitable for printed glass

cut the glass according to the user's requirements, which can be regular or irregular shape, then reverse edge grinding, cleaning and drying for use. Special attention should be paid here that there should be no water stains on the surface of flat glass

selection of silk

the screen printing plate for flat glass printing is the same as the general screen printing plate. The glass screen printing plate adopts synthetic fiber, stainless steel wire and natural fiber. When printing general color materials, the above silk can be used. Generally, cheap synthetic fiber silk is selected; When it is used as gold and silver decoration, stainless steel wire cannot be selected. The specification of silk is generally 270 ~ 300 mesh

selection of frame

at present, the relatively regular frame with little deformation is aluminum alloy frame, and its size should be larger than the pattern. The specific size should be that the outer edge of the pattern should be between 70 ~ 100mm from the frame. In addition, the strength of the selection box is very important, and the key is the sufficient rigidity in the horizontal direction

taut

selected silk and box, and combined the two, which is taut. There are many ways to stretch, including manual, motorized and pneumatic methods. At present, the more advanced one that can stretch the high-quality version is the pneumatic stretching machine. The tension is required to be uniform, the yarn warp and weft remain vertical, and the viscose should be firm and not loose

choose photosensitive adhesives

at present, the photosensitive adhesives on the market include dichromate system, diazonium salt system and iron salt system. The requirements for photosensitive glue in screen printing plate making are: good plate making performance and easy coating. The photosensitive spectrum range is 340 ~ 440nm, with good development performance, high resolution, good stability, easy storage, economy, sanitation, non-toxic and pollution-free. The requirements of printing on photosensitive materials are that the plate film formed by photosensitive materials can meet the performance requirements of different kinds of inks. It has considerable printing resistance and can withstand the scraping pressure of the doctor blade for a considerable number of times; It has good adhesion with silk, and there is no film failure during printing; It is easy to peel, which is conducive to the recycling of silk plates. The DS Series photosensitive adhesive produced by Beijing Taipingqiao Printing Material Factory has good effect and basically meets the requirements of flat glass fiber printing

print

after selecting the above material, apply photosensitive glue in the darkroom; It is required to be uniform, and then dry. Generally, it is required to apply twice. It is required to expose the light on the cold light source printer, which can be used to control the light of DC electromechanical or pneumatic, hydraulic and other power devices. The exposure time should be determined according to the pattern, generally between 12 and 30 minutes. After exposure and development, a silk screen version is made

printing

there are manual, semi-automatic and full-automatic printing machines for flat glass. The manual printing machine is suitable for small batch and small specification flat glass. The semi-automatic and full-automatic printing machine is suitable for large batch, large-scale multi chromatic printing, with the advantages of accuracy and speed. The largest semi-automatic printing machine can print 2000 × 1500mm size glass. The full-automatic printing machine is generally used for the printing of automobile windshield, and several foreign companies can provide this kind of equipment

ink

decorative ink for flat glass is divided into organic ink and inorganic ink. The colorant and connecting material of organic ink are organic. The effect of this ink on decorating flat glass is also good, but the firmness of the film is poor, and the chemical stability is not good. It is a short-lived decoration method. Inorganic ink is composed of colorants, fluxes and bonding agents. Colorants are inorganic colorants such as chromium oxide and cobalt oxide. The flux is low melting point glass, and the common ones are lead oxide and borosilicate glasses. The most important thing about the performance of flux is that it is not too different from the thermal expansion coefficient of printed glass. The composition of typical flux: SiO2 19182% the auxiliary equipment of plastic extrusion unit mainly includes setting out device, straightening device, preheating device, cooling device, traction device, meter counter, As2O3 2113%, MgO 0146%, PBO 62110%, Cao 0127%, K2O 1183%, B2O3 10175%, Al2O3 1163%, Na2O 1176%. Scraper oil, the connecting agent in inorganic ink, is an organic substance, which is completely burned in the sintering process, but has no effect on the decorative effect

the composition of scraper oil is: 3G ethyl cellulose, 100ml terpineol, 10ml turpentine, 5ml alkyd resin. The proportion of pigment and connecting agent of inorganic ink is 10g ∶ 8ml, which can be obtained by stirring and grinding

sintered

glass is an amorphous inorganic material, which softens with the increase of temperature. When heated to the softening temperature of glass, the glass will deform. The colored glaze of glass is decorated on the surface of flat glass through silk screen printing and needs to be consolidated on the surface of glass through high-temperature sintering, but the sintering temperature must be lower than the softening temperature of the decorated glass to ensure that the decorative glass does not deform. Generally, the sintering temperature of glass glaze is not higher than 520 ℃, which is usually controlled at 480 ~ 520 ℃

low temperature glass glazes are produced by several manufacturers in China, which can effectively avoid the emission of toxic gases containing fluorine and chlorine and slag when refining with flux, and the price is relatively low. Several international companies can also provide similar products, but the price is ten or twenty times higher than that of domestic ones. The domestic consumption level has not reached the level of using this kind of glaze, but the glaze provided by foreign countries is indeed much better than the domestic color and level. It is inevitable to improve the quality of decorative glass and the grade of glaze. Sintering equipment includes flame furnace and resistance furnace. Resistance furnaces are divided into vertical hanging type and horizontal roller table type according to the hanging mode of glass. The vertical hanging sintering furnace has the advantages of small sintering deformation, independent investment projects, and a yield of more than 95%, but the equipment is complex. In addition, it is also feasible to use the horizontal tempering furnace to produce decorative glass. The grade of the product is improved and the safety is guaranteed. It is an ideal sintering method

source: Chinese silk screen printing profession