Quality defects of melamine impregnated paper faced MDF (patterned board) ,quality assurance,inspection checklist ,factory auditing,sourcing service,Laboratory testing ,inspectors

Common quality defects of melamine impregnated paper faced MDF (patterned board) and their causes 1. Poor physical properties ① Low hot pressing temperature or short hot pressing time, incomplete tree curing, and easy adhesion of dust on the board surface during use, not easy to clean, resulting in dirty surface. ② The hot pressing temperature is too high, the surface temperature of the formwork is uneven or the degree of the base material is uneven, which is easy to form cracks on the board surface (commonly known as cracking). ③ Paper resin content is too low, resulting in low surface separation strength of the substrate. ④ Excessive unit pressure, uneven plate density, asymmetric structure and high hot pressing temperature cause panel warping. ⑤ The moisture content of the board is too high, the base material is broad, and the board density is too low. When pressing and pasting, the core layer will generate large steam pressure, which will make it bubble or delaminate. 2. Uneven gloss of the board surface ① The dipping amount of the impregnated paper is uneven, the water content of the board is too high, and bubbles appear locally on the board surface when pressing, resulting in uneven light selection of the board surface. ② The formwork surface is polluted, the surface is dirty or the cushion pad is damaged, and the temperature of the base plate is uneven, resulting in poor demoulding. ③ The water content of the board is too high, the hot pressing temperature is too low or the hot pressing time is too short, which leads to the water penetration of the board surface and uneven luster of the board surface. ④ Low hot pressing pressure or long storage time of impregnated paper. The resin has a high degree of pre solidification, and the resin fluidity is poor during hot pressing, resulting in poor board surface brightness. ⑤ Dirt or hand print on the surface of the board when assembling, paper, etc. 3. Board surface dry flowers (also known as dye white flowers or white spots) ① There is a local pre curing layer on the surface of the substrate, resulting in low board density at this place, resulting in large resin absorption, resulting in poor resin fluidity on the board. ② The base material is locally depressed Insufficient pressure at the concave during hot pressing affects resin flow. ③ The hot pressing temperature is too high, the hot pressing pressure is too low or the formwork surface is painted with dirt. ④ The buffer pad is partially damaged or has been used for a long time, which causes the local temperature of the pressing plate to be too high and uneven heating of the plate surface, resulting in dryness. ⑤ The storage period of impregnated paper is too long, the degree of pre solidification is too high, the fluidity of tree land is poor, or the resin impregnation amount is too large, resulting in steam bubbles on the board surface and dry flowers when pressing. 4. The water content of the base material is too high, and excessive blisters are produced when pressing. ② The volatile content in the impregnated paper is too large or the impregnated paper is affected with moisture. ③ The hot pressing temperature is low or the hot pressing time is short. 5. Die bonding electrode plate (that is, bad demoulding) ① The amount of impregnated resin is too large or there is dirt on the surface of the template. ② The hot pressing temperature is low, the time is short, and the resin is not completely cured. ③ The flushing pad is partially damaged, resulting in uneven formwork surface and low local temperature. ④ The high moisture content of the board affects the resin curing and leads to poor demoulding. To sum up, in order to produce high-quality products, we must select excellent impregnated paper and substrate, and adopt reasonable processing technology; In addition, operators and inspectors should cooperate with each other to control the quality of products, find out the causes of problems and solve them in time, so as to ensure the quality of products