Requirements of food packaging bags for liquid resin plate making process

Liquid photosensitive resin plate, referred to as liquid resin plate. Before photosensitivity, the resin is not viscous and transparent liquid. After photosensitivity, the resin is cross-linked into a solid. The resin is the main component of the photosensitive resin, which is generally the unsaturated resin obtained by polycondensation of aliphatic and aromatic saturated and unsaturated polyols. Liquid resin plate, a ready to coat plate, is cheap, and its flexibility has a great impact on the temperature. It is suitable for making line or character plates with small size. The plate making process of liquid resin plate generally goes through such processes as flow laying, exposure, washing, drying and post exposure. 1. Flow laying: the function of the crosslinking agent is to make liquid or solid resin polymerize Crosslinking to become a solid or increase the hardness of a solid. When the photosensitive resin flows out of the hopper, the scraper at the top of the hopper will hang the photosensitive resin to a certain thickness. The uniformity of the thickness is the key to this process. 2. Exposure: It is to cover transparent film on the flow sensitive resin, and then place the positive negative paper. The front exposure is first performed, and then the back exposure is generally 10 times as long as the back exposure. High voltage silver lamps rich in ultraviolet light are commonly used as light sources. The light energy output of the exposure machine is determined by the new and old types of light sources. The exposure of different batches of plates is also different. The determination of front exposure requires a test strip, and the determination of back exposure requires one or two experiments. 4. Drying and post exposure. It is to put the washed photosensitive resin plate into the infrared ray for drying, and expose it again after the photosensitive resin plate is dried. The purpose is to increase the mechanical strength of the printing plate, improve the printing resistance. The liquid resin belongs to the instant coating plate, which is cheap, has poor dimensional stability, has a large impact on the temperature and humidity of the plate surface scalability, and is suitable for making line or text printing plates with small size.