Rotary screen printing is a printing method in which the color paste in the rotary screen is printed on the fabric under the pressure of a scraper.
One, open type rotary screen printing machine structure
The open type rotary screen printing machine usually consists of four parts: cloth feeding device, printing head, drying device, and cloth dropping device. At present, open type rotary screen printing machines usually have eight-color, twelve-color, sixteen-color, and twenty-four-color open type rotary screen printing machines. There are mainly two types of printing machines, 640mm and 904mm. Among them, the open type rotary screen printing machine with 640mm flower back is mostly. The open type rotary screen printing machine has the advantages of simple operation, low labor intensity, and high output. It is suitable for printing various fabrics. At the same time, it is suitable for printing many varieties of small-batch fabrics.
(1) Cloth feeding device open type rotary screen printing machine There are two types of cloth feeding device: cloth car feeding and cloth roll feeding. When the cloth is rolled into the cloth, the oscillating cloth guiding roller can be pressed on the cloth roll, and the cloth can be guided into the printing device by the rotation of the cloth guiding roller. When the cloth is fed in, the fabric will move forward with the circulating rubber track to complete the printing. This crawler is first coated with a thin layer of thermoplastic resin on the surface of the rubber roller so that the fabric can be glued smoothly. An infrared radiant heater is installed next to the rubber roller to heat the resin on the track. Thermoplastic resin coating can process 200,000 to 1 million meters of fabric at a time. If you find that the viscosity is not good, you can recoat it.
(2) Printing device Rotary screen printing device includes rotary screen, scraper, pulp feeding device, etc.
1. Rotary screen is the pattern of the printing machine. It is made of nickel metal, also called nickel mesh, with hexagonal mesh. Both ends of the rotary screen are fixed with bulkheads to prevent deformation of the rotary screen during printing, which affects the accuracy of the flower, and can withstand the pressure of the color paste and the squeegee during printing. To improve the elasticity of the rotary screen and reduce the pressure it bears, the rotary screen should be installed off the centerline of the support roller, generally about 16mm. Each cylinder frame has a reading device, which can show the pressure of the scraper in all directions.
2. Scraper The squeegee of the open type rotary screen printing machine is installed on the squeegee frame on the centerline of the rotary screen. The scraper rack is equipped with both scrapers and slurry pipes. The scraper is made of chromium, molybdenum, vanadium, and steel alloys, and has the characteristics of a small friction coefficient and adjustable angle. When printing, the blade edge of the squeegee is tangent to the inner circle of the cylinder, and the squeegee applies pressure to the color paste mainly and scraping as a supplementary compound action.
The pressure and position of the scraper of the open type rotary screen printing machine can be adjusted to suit various patterns and fabric printing of various thick and thin color pastes.