Like glue, in the glue spraying process, the flame retardant is added to the density board, and then heated to form. Fire shutters are mainly used for the decoration of public places, and no one knows much about it. The following is an introduction to the difference between flame-retardant MDF and ordinary MDF and common problems.
1. Flame retardant board is different from ordinary density board.
Flame retardant board belongs to density board, which is a kind of functional density board. The appearance is red, mainly because the fiber is dyed red according to international practice to distinguish it from ordinary density boards. However, red MDF boards are not necessarily flame retardant boards, and flame-retardant test identification is also required.
2. Identification method of flame retardant MDF.
(1) Water absorption rate measurement: the addition of flame retardant will affect the water swelling performance of the board. After taking the number, use a micrometer to measure the thickness of the sample, and then soak it in water for 24 hours. Measure the thickness again, and calculate the percentage of thickness change before and after immersion, which is the expansion rate of the water-absorbing thickness. If it is changed, the possibility of fireproof mdf board is very high.
(2) Combustion performance test: flame retardant mdf is a density safety board with flame-retardant and fire-proof functions. A simple burning test can tell: Use a blade with a diameter of 2-3 mm (2-3 mm in diameter) to burn for 5 seconds away from the fire. After leaving the fire, it will self-extinguish within 10 seconds and there is no spark, which can reach CVT level of C level;
3. Common problems of flame retardant MDF.
(1) The board surface is rough and uneven, which affects the reprocessing of the board.
(2) There are stains, oil stains and other pollution on the surface of the board, which affect the reprocessing of the board.
(3) The thickness deviation is large.
(4) The board has high bark.
(5) Water resistance cannot meet the requirements of some applications at present.
(6) The middle-layer board is soft, the nail clamping force is large, the internal bonding strength is low, and the edge of the board is rough.
(7) The amount of formaldehyde that affects human health exceeds the standard.