Common quality problems and solutions of melamine paper impregnated paper lamination factory lamination
1、 Dry flower on the board surface.
Dry flowers, also known as white flowers, are opaque white spots on the surface of products. The main reasons for this defect are poor resin flowability or insufficient resin impregnation, which can be caused by various factors:
1) The substrate inspection is not strict, the surface is uneven, and local depressions are too deep. Insufficient pressure at the depressions during pressing affects the resin flow and produces dry flowers;
2) The local pre cured layer on the surface of the substrate is not sanded clean, resulting in a low density of the board surface and a large resin absorption amount. Therefore, the resin amount is insufficient during pressing, resulting in poor resin flowability and dry flowers on the board surface;
3) The adhesive film paper used for pressing and pasting is not evenly impregnated during the impregnation process, and there are adhesive clusters or obvious uneven coating in the surface paper.
4) The pressing temperature is too high, the pressing pressure is too low, and there are pollutants on the surface of the hot pressing plate;
5) The buffer pad is partially damaged, resulting in excessive temperature in the local area of the pressure plate, resulting in dry spots, and uneven heat transfer between the steel plate and pressure plate;
6) The storage period of adhesive film paper is too long, the pre curing degree is too high, or the pH value of the substrate is too low, which affects the resin flow and causes dry flowers;
7) Excessive soaking of adhesive film paper can lead to steam bubbles on the board surface during pressing, which can also cause dry spots.
8) The balance paper shows severe bottom penetration locally, resulting in excessive temperature difference and local dry spots.
2、 Wet flower on the board surface.
Wet flowers, also known as water marks, are foggy marks on the surface of a product. Causes of wet flowers
1) The volatile matter content of the adhesive film paper is too high, which cannot be discharged during pressing and accumulates on the board surface, or the adhesive film paper becomes damp;
2) The pre curing of the adhesive film paper is too low, the hot pressing temperature is too low, or the hot pressing time is too short;
3) The moisture content of the substrate is too high, resulting in excessive moisture generation during pressing.
3、 The product is layered and bubbling.
The main reasons for layered bubbling are:
1) The hot pressing temperature is too high and the hot pressing time is too long;
2) If the moisture content of the substrate is too high or the thickness of the substrate is too thin, the core layer of the sheet will generate significant steam pressure during pressing;
3) Low substrate density, poor compressive performance of the board, or excessive hot pressing pressure;
4) The substrate contains impurities (such as plastic film or agglomerated paraffin, etc.)
4、 Stick the template.
Sticking the template refers to the process of partially or completely sticking the board to the template during the pressing process,
The main reasons are as follows:
1) Short hot pressing time, low or locally low temperature of the hot pressing plate, resulting in incomplete curing of the resin and poor demolding;
2) The high moisture content of the substrate or the high pH value of the substrate affect the resin curing, resulting in poor demolding;
3) The surface of the template is not clean, there is no release agent in the resin, or the release agent is ineffective or unevenly applied;
4) The soaking amount of adhesive film paper is too large, and the volatile matter content is too high;
5) Inaccurate positioning of the slab during hot pressing;
6) The partial damage of the buffer pad causes uneven surface temperature of the template, resulting in poor demolding.
5、 Uneven gloss on the board surface.
Caused by improper control of the printing quality and lamination process of decorative paper. The main reasons are:
1) The resin impregnation amount of impregnated paper is large, and the distribution of impregnation amount is uneven. During the pressing process, bubbles appear locally on the board surface, resulting in uneven gloss on the board surface.
2) The surface of the template is contaminated and not smooth, or the surface temperature of the template is uneven and demoulding is poor, resulting in uneven surface gloss;
3) The residual volatile matter of impregnated paper is relatively high, or the moisture content of the substrate is too high, the hot pressing temperature is too low, or the hot pressing time is too short, resulting in water stains on the surface of the board and uneven luster;
4) Factors such as low hot pressing pressure, long storage period of impregnated paper, high pre solidification degree of impregnated paper, and low pH value of the substrate can lead to poor resin flowability and uneven surface gloss.
6、 The physical performance of the product is poor.
The main reasons are:
1) Low hot pressing temperature or short hot pressing time, resulting in incomplete resin curing and affecting the physical properties of the product;
2) Excessive hot pressing temperature, uneven surface temperature of the template, long storage period of the impregnated paper, and high pre solidification degree of the impregnated paper result in poor resin flow spread and affect the physical properties of the product;
3) Low weight of impregnated paper, low resin impregnation amount of impregnated paper, or uneven distribution of resin impregnation amount affect the physical properties of the product.
7、 The moisture content of the substrate has a significant impact on the quality of the decorative panel.
1) If it is too low, it may cause the surface to not be well wetted during hot pressing, resulting in cardboard separation, insufficient bonding strength and adhesion, and affecting the effective flow of resin, resulting in poor surface smoothness of the board;
2) If it is too high, there will be too much moisture vaporized inside the substrate during pressing, which not only fails to achieve the required bonding strength, but also easily causes bubbles and delamination during hot pressing.
