What should be paid attention to in the brush stroke of artificial leather forming process

2018-11-18 10:06:39

　　First: there are traces on the leather surface. 1. There are foreign matter impurities in the paste or surface treatment agent. It should be completely removed. 2. The surface of the steel strip has deep scratches. New steel strips should be exchanged.

　　Second: the leather surface pattern is unclear 1. The embossing roller is not placed horizontally. Should be adjusted to a horizontal position. 2. The temperature of the roll surface is not uniform, and the temperature at both ends is low. An auxiliary heat source should be added at a low temperature to make the roll surface temperature distribution uniform.

　　Third: After the coiling and storage, there is a cloth on the leather surface. 1. After cooling, the cooling is insufficient. Cooling should be strengthened. 2. The storage environment temperature is too high. Store the finished product in a low temperature environment

　　Fourth: There are regular defects on the leather surface. 1. There are impurities on the surface of the rubber roller of the press roller or embossing machine. The impurities on the roll surface should be completely removed. 2. Roll surface defects. The roll surface should be ground to remove roll surface defects.

　　Fifth: the bubble on the leather surface 1. The foaming temperature is too high. The foaming temperature of the plasticizing oven should be appropriately lowered. 2. The moisture content in the paste is too high. • Remove moisture from the paste or switch to a paste with a lower moisture content. 3. The cloth base is wet. Should be dried

　　Sixth: foaming after foaming (1) Xiao lost 1. The nip of the embossing roll is too small. The pressure of the embossing roller should be appropriately reduced to increase the nip. 2. The traction is too large. The traction pull of foamed artificial leather should be appropriately reduced

　　Seventh: the leather surface is convex. 1. The raw material is moist. Pre-drying should be carried out. 2. The volatile content of the formula is too high. Volatile additives should be avoided in foaming formulations. 3. Improper use of additives. Fast gel plasticizers and slower accelerators should be used. At the same time, a higher starting temperature should be used.

　　Eighth: uneven foaming of the leather surface 1. The air content in the plastisol is too much. The paste should be degassed. 2. The foaming agent is poorly dispersed. The blowing agent should be ground together with the plasticizer

　　Ninth: The lateral thickness of the leather surface is not uniform 1. The lateral thickness of the coating is not uniform. The distance between the rollers of the coating machine should be properly adjusted to make the coating thickness uniform. 2. The temperature of the plasticizing foaming oven is not uniform. The oven temperature should be adjusted appropriately to distribute the temperature evenly.

　　Tenth: The foam layer is not firmly bonded to the cloth base or peeled off. The gel temperature is too high. The temperature of the preheating oven should be appropriately reduced. 2. The brush roller is too far from the cloth base. The distance between the roller surface of the brush roller and the cloth base should be properly adjusted. The foam layer cannot be peeled off from the steel strip when driving. The temperature of the steel strip is too high. Should be appropriately lowered

　　Eleventh: Deformation of steel strip deformation 1. The steel strip is unevenly deformed by heat. The steel belt should be operated before the temperature rises, and then the steel belt is cooled before stopping. 2. The tension rollers are not parallel, causing the steel strip to deflect when it is running. The tension of the steel strip should be adjusted in time to run in the middle of the tension roller.

　　Twelfth: Discoloration of the coating film 1. Improper use of the curing agent and stabilizer. Lead-containing priming agents should be avoided for use with sulphur-containing tin stabilizers. For example, a lead-containing initiator is used in the inner layer, and a sulfur-containing tin stabilizer is used in the surface layer, which causes discoloration of the coating film.

　　Thirteenth: cloth base oil 1. Preheating oven temperature is too low. The temperature of the preheating oven should be increased appropriately or the small exhaust vents should be closed. 2. The viscosity of the paste is too low. Should be properly improved