Wuhan Handern low-pressure laminate
DATE：2020/5/25 9:01:36 / READ： / SOURCE：This station
Wuhan Handern low-pressure laminate
A low-pressure veneer 2 with production costs lower than the high-pressure laminate and appropriate protection and decoration has been developed. When using the low-pressure laminate, the resin-impregnated paper and the substrate are placed in a cotton press. The resin is polymerized directly on the surface of the substrate and a laminate is formed. The low lamination pressure used in this process prevents the matrix from being crushed. www.handern.com Laminating equipment
The substrates commonly used in low-pressure laminates include particle boards, which have been sanded with 100-mesh grit and have a density of 650-680 kg / cm ’. It is also useful for medium density fiberboard and hard fiberboard. www.handern.com Laminating equipment
The covering material is mainly decorative paper impregnated with melamine. Some polyester-treated paper is also used. The decorative paper is made of a cellulose with a quantitative range of 80 ~ 120g / m2. They are impregnated and saturated to a resin content of 56% to 59% (including 6% to 7% volatiles). www.handern.com Laminating equipment
The other paper used on the surface of the low-pressure laminate is impregnated with urea-formaldehyde resin to a content of 35% to 45%. This type of paper may be monochromatic or white, or may be decorative paper such as melamine impregnated. In the latter case, the paper is usually coated with nitrocellulose varnish or polyacetal resin before lamination. www.handern.com Laminating equipment
Most low-pressure laminates have only one sheet of resin-impregnated paper on their surface. Only use two sheets of paper to solve the problem of light transmission or to hide the roughness or porosity of the substrate surface. www.handern.com Laminating equipment
For particle board and medium density fiberboard, laminates are added on both sides to prevent curling. Rigid fiberboard is only laminated on the smooth side. When the rigid fiberboards come off the press, they are moisturized on the bottom side to prevent the tendency to curl.
The surface texture of low-pressure laminates, like high-pressure laminates, can be achieved with reliable release paper. But from an operational point of view, it is difficult to do. The surface is usually realized by the surface of the polishing plate used, and the surface of the panel is a replica of the polishing plate used. Because the press usually has only one opening, the specially processed polished surface is not a major expense. www.handern.com Laminating equipment
The press is a single-port short-cycle press with a normal operating rate of 70 to 120 cycles / h. The pressure, pressing time and temperature vary with the specific paper and substrate used. For particle board and medium density fiberboard, the pressure is (1964 ~ 2480kPa). For hard fiberboard, the pressure used is (2963 ~ 3962kPa). The temperature of the hot plate is about 33.3C higher than the temperature required to cure the resin. The melamine impregnated paper needs a temperature of 140 ~ 150'C for a fast curing time of 35s. This requires a hot plate temperature of 200 ~ 210C. Including loading and unloading time, the press cycle is 70 times per hour. The temperature used to impregnate saturated paper with urea-formaldehyde resin is similar. It takes about 14 seconds for the dry glue line to set. The setting time for the wet glue line is about the same, but the temperature is lower. If you only need to set the glue line, the cycle may be up to 120 times per hour. www.handern.com Laminating equipment
For low-pressure laminates, the carrier of the press is a single laminate composed of a base plate plus decorative paper on the top and bottom surfaces. Dealing with decorative paper on the underside of the substrate is a problem. Sometimes the paper is applied to the bottom surface of the board with a wet glue line. www.handern.com Laminating equipment
Enenbergrlod introduced a method in which the substrate is charged with static electricity to attract the paper through the charged static electricity. Since low-pressure laminates include substrates, they are more loose than high-pressure laminates. This makes them less convenient to transport to very long distances. Therefore, they are generally produced near furniture manufacturing plants. www.handern.com Laminating equipment
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