The needle is also the collective name for the micropores on the screen. It can produce print sticky, local ink layer deposition, thinning the drawbacks. Due to the uneven surface area of ​​the photosensitive adhesive on the surface of the screen, the level printing becomes more unstable, and the color difference becomes more apparent, which will also greatly reduce the service life of the screen.
Analysing the causes of pinholes and taking countermeasures in the entire process of screen printing will greatly benefit the quality of screen printing.
First, the reasons for pinholes After the development of screen pinholes, often caused by the following reasons:
1) Incorrect screen degreasing treatment.
2) Debris residues remain before rinsing and dry on the screen surface.
3) The method of drying the paste after coating 4) The method of drying the paste after coating 5) Put the screen with the developed screen or degreasing screen after drying 6) The screen is not completely dry yet Exposure 7) Dust and dirt adhered to the printing plate 8) Dust adhered to the platen glass of the printing machine 9) Dust particles in the plate making room air fell on the sensation 10) Dust was adhered to the rubber hopper 11) Coating speed Not 12) Inadequate mixing of latex and diazo sensitizer 13) Sensitized photoemulsion is left for too long 14) Water source is not clean enough 2) Pinhole solution method 1) Make sure that the correct degreasing treatment method is used. When degreasing, defatted continents are evenly coated on the screen surface and brushed thoroughly with a brush. Start with the printing surface, and then brush the plate making surface for about 3-5 minutes.
2) The presence of chemicals such as degreasing agents on the screen will damage the screen. Manufacturers have detailed instructions for them. Before performing the next process, be sure to wash with pressure water to ensure that the screen is thoroughly cleaned. The standard of screen washing is that the screen surface can be evenly adhered to a layer of water suede, otherwise it must be re-degreased.
3) Appropriately increase the coating thickness. For layer printing, direct film or indirect film adhesion method should be adopted. For direct method, the thickness must reach 7-8μm, otherwise pinholes may easily occur.
4) Drying after screen coating should be done in the correct way. The screen should be placed horizontally for drying. The drying temperature should be below 40 degrees Celsius. Otherwise, pinholes may appear on the upper part of the screen. (To be continued)
Analysing the causes of pinholes and taking countermeasures in the entire process of screen printing will greatly benefit the quality of screen printing.
First, the reasons for pinholes After the development of screen pinholes, often caused by the following reasons:
1) Incorrect screen degreasing treatment.
2) Debris residues remain before rinsing and dry on the screen surface.
3) The method of drying the paste after coating 4) The method of drying the paste after coating 5) Put the screen with the developed screen or degreasing screen after drying 6) The screen is not completely dry yet Exposure 7) Dust and dirt adhered to the printing plate 8) Dust adhered to the platen glass of the printing machine 9) Dust particles in the plate making room air fell on the sensation 10) Dust was adhered to the rubber hopper 11) Coating speed Not 12) Inadequate mixing of latex and diazo sensitizer 13) Sensitized photoemulsion is left for too long 14) Water source is not clean enough 2) Pinhole solution method 1) Make sure that the correct degreasing treatment method is used. When degreasing, defatted continents are evenly coated on the screen surface and brushed thoroughly with a brush. Start with the printing surface, and then brush the plate making surface for about 3-5 minutes.
2) The presence of chemicals such as degreasing agents on the screen will damage the screen. Manufacturers have detailed instructions for them. Before performing the next process, be sure to wash with pressure water to ensure that the screen is thoroughly cleaned. The standard of screen washing is that the screen surface can be evenly adhered to a layer of water suede, otherwise it must be re-degreased.
3) Appropriately increase the coating thickness. For layer printing, direct film or indirect film adhesion method should be adopted. For direct method, the thickness must reach 7-8μm, otherwise pinholes may easily occur.
4) Drying after screen coating should be done in the correct way. The screen should be placed horizontally for drying. The drying temperature should be below 40 degrees Celsius. Otherwise, pinholes may appear on the upper part of the screen. (To be continued)
Plastic Cosmetic Bottles,Acrylic Plastic Cosmetic Bottles,Cosmetic Bottles
Beautypacking International Trade Co., Ltd. , http://www.shacryliccreamjar.com