As a material for architectural decoration, glass has the advantages of being flat and transparent and easy to scrub. The pattern of glass after screen printing is exquisite and beautiful, and it can be colorless or colored. It is more popular for building decoration and substantially meets people’s aesthetic needs. People use screen printing to print images directly onto the glass surface. Screen printing could also be used to make preservatives, etc., on parts of the glass surface, so that they are not affected by etching or sanding. It is also possible to directly print special inks to create an engraving or matte effect. You can see screen-printed glass everywhere of your life, such as display windows, building partitions, building exteriors, car windshields, glass bottles and more. At the same time, they are also widely used in furniture decoration and game tools, as well as in countless decorations and artistic creations.
So, how to screen printing on the glass?
Traditional screen printing has been circulating for so many years, although the process of glass screen printing has undiversified. The process of glass screen printing is as follows.
Glass cutting → edging → punching → cleaning → Making screen printing plates → glaze preparation → screen printing → drying → sintering → finished product
The glazes of screen printing flat glass are generally 240 mesh, and the screen printing mesh 220 mesh is commonly used for glass screen printing.
The screen for glass printing is the same as the conventional screen printing screen. The silkscreen fabrics which to be used depends on the printing purpose. Higher mesh count 300 to 360 mesh is required for high precision fine glass products. The synthetic mesh includes polyester & nylon can be used for infrared hot stamping glaze printing. This type of screen printing extensively used because its economical for a small number of varieties of glass screen printing.
To get the desired printing effect on the glass, first, create a design on the screen to block the silk mesh that does not need to be printed. When the glazes ink spread evenly by the squeegee on the screen, it will not pass through the part of the stencil. In other areas where there is no blocking, the glazes will adhere onto the glass through the silk mesh to obtain a high-quality image. The image screen printing on the glass can be precise, and transparency is adjustable.
Glass is an amorphous inorganic material that softens as the temperature increases, it will deform and when heated to the softening temperature. During the colored glass screen printing, each color requires a separate film design. After decorating the ink screen on the glass, sometimes they need to heat and sinter the ink to “burn” the ink onto the glass to fix the image and get a colorful decorative pattern. However, the sintering temperature must be lower than the softening temperature of the glass to be printed to make sure that the glass will not be deformed. Generally, the sintering temperature for the glass glazes should be lower than 520 ° C, usually between 480 ° C to 520 ° C.
Combine glass screen printing with other processing methods, you will get better artistic effects. For example, etching, ice patterned, frosting, and defogging, etc could achieve by glass surface process and accomplish a variety of artistic effects and practical functions.
The production process of embossed glass is to print the cosolvent on the glass surface first, then sprinkle the glass particles and fuse the then by 500 ° C – 590 ° C high-temperature sintering, to obtain empaistic glass.
The silkscreen etching process is to screen print the anticorrosion material on the glass surface in the designed pattern to form a resist membrane. The portion out of the resist membrane is exposed to be etched, and the etching is performed by hydrofluoric acid.
The production method of frosted glass by screen printing is as follows — screen printing the pattern on the glass surface with a refractory agent. After high-temperature baking, the area out of the screen printed refractory pattern will melt and become transparent, and the printed part will form a special frosted image.
Electric heat defogging glass also realizes by screen printing. To prevent the condensation of water vapor on the window glass, screen print the electrically conductive ink in lines on the glass, and fix them by heating. When the window is foggy, the lines generate heat through the current, increase the temperature of the glass surface, and remove the water vapor.
The glass screen printing application will continue developing and expanding its appeal in glass decoration. In addition to its suitability for substrates of various glass materials, another important reason is screen printing could meet glass substrates in different sizes and weights. Moreover, due to the absolute superiority of screen printing in ultra-large format image printing, it has strengthened its leading position in the development of the entire glass printing industry. In particular, in recent years, the demand for large-format flat glass printing has risen sharply.