Problem solving in fireproof laminate manufacturing
Fireproof laminate is a refractory material for surface decoration, and it is made of kraft paper treated by melamine and phenolic resins impregnation, and applying high temperature and high pressure. There are defects in production of fireproof laminate, here are some solutions.
Surface cracking
Reasons
- Resin reaction time is not long enough;
- Resin curing is incomplete;
- Impregnated paper has too much resin.
Solutions
- Stop using unqualified resin;
- Increase hot-press temperature or extend hot-pressing time;
- Control impregnated paper with suitable resin content.
Layered phenomenon
Reasons
- Lacking of volatiles in the impregnated paper to cause local resin to cure in drying;
- Resin content on the impregnated paper is not enough;
- Pressure is too low, or hot pressing time is not enough;
- Impurities between impregnated papers.
Solutions
- By controlling the volatile content from being too low, drying temperature from being too high, drying time not too long will prevent resin from local curing;
- Improve resin content on the impregnated paper;
- Increase pressure and prolonged heating time properly;
- Remove impurities in operation.
Warping
Reasons
- Uneven thickness of raw paper;
- Uneven resin of impregnated paper, various pressures;
- Fail to adequately cool after heating in pressing process.
Solutions
- Ensure all kinds paper meets the process requirements;
- Maintain uniform resin concentration, adjust lap of the squeeze roller;
- Pressure removal after cooling below 50°.