First, the glue spraying process caused by "blocking gun"
Reason analysis:
1, glue contains too much impurities;
2, the use of inferior spray gun;
3, the glue wetting, leveling poor.
The solution:
1, filter impurities;
2, choose high quality spray gun;
3, add appropriate additives to improve its wetting, leveling agent.
Two, the edge can not suck or shrink
Reason analysis:
1, blister, the side temperature is low or the vacuum degree is not enough;
2, the temperature resistance of glue is not enough;
3, after the blister molding, in the case that the temperature has not fallen, the pressure is withdrawn.
The solution:
1, increase the temperature or vacuum degree;
2, the use of curing agent;
3. After blister molding, the temperature is cooled to room temperature or slightly higher before the vacuum is withdrawn.
3. Local foaming
Reason analysis:
1, the spray glue is not uniform, resulting in less local glue, so that the bond strength is reduced;
2, the problem of PVC film, PVC film contains plasticizer, in the case of aging or heat, plasticizer is easy to migrate to the surface, affecting the bond strength;
3. There is a problem with the heating tube in the blister machine, resulting in uneven temperature.
The solution:
1, as far as possible to spray the amount of uniform;
2, use good quality PVC film;
3, timely maintenance of equipment.
4. Large area foaming
Reason analysis:
1, the temperature or pressure does not meet the requirements, resulting in false suction;
2, the amount of glue is not enough, the spraying amount is less or the plate is permeated;
3, preheating time is not enough (softening PVC film) or blister time (molding time) is not enough;
4, after the blister molding, in the case that the temperature has not fallen, the pressure is withdrawn.
5, the heat resistance of the glue itself is not enough.
The solution:
1, increase the temperature or vacuum degree;
2, increase the amount of sizing, choose good quality plate;
3, increase the preheating time or blister time;
4. After blister molding, the temperature is cooled to room temperature or slightly higher and then withdrawn from the vacuum.
5. Use 3-5% curing agent.
Five, not enough stickiness
Reason analysis:
1, the proportion of deployment of plastic suction is uneven;
2, add different additives caused by.
The solution:
1. Appropriately adjust or increase the content or composition of PUD;
2, check whether the additives or additives added have special reactions, and do more experiments in order to achieve the best production formula of plastic suction.
Six, there are pockmarks on the surface of the product
Reason analysis:
1, the size of the glue is large, the use of thin PVC film, easy to produce pitting, such pitting is characterized by uniform dispersion;
2, when the curing agent is used, the curing agent is not completely dispersed;
3, the surface of the plate is not treated clean, or after spraying glue, the workshop dust is large, glued on, this pitting point dispersion is very uneven, and the size is different;
4, the viscosity of the glue is too large, uneven dispersion;
5, the viscosity of the glue is too small or the solid content is low, causing the plate to fuzz, such pitting points generally appear in the corner of the groove, the block appears;
6, the air pressure of the spray gun is not enough, the atomization is not good;
7, the glue is not filtered (this situation refers to: a bucket of glue used in the end, if it falls into the stolen goods or conjunctival production, to filter with a filter).
The solution:
1, choose the glue with small particle size;
2, with curing agent, extend the mixing time, so that curing agent can be completely dispersed;
3. Clean the surface of the plate before spraying, and the spraying workshop should be separated separately;
4, choose the right viscosity of glue or high solid content of glue;
5. After the glue is dry, it can be polished with fine sandpaper.
6, increase the vacuum degree, adjust the atomization effect;
7, when in use, filter with a filter.
