Melamine impregnated paper is the paper that is soaked in melamine-formaldehyde resin and urea-formaldehyde resin. According to the application, melamine paper mainly has 3 types – melamine decorative paper, melamine balance paper, and melamine overlay paper. Among them, melamine decorative paper is the most widely used type in the wood industry.
As the decorative paper is without impregnating glue, it cannot be laminated on the wood-based panel directly. In order to join the decor paper to wood materials, paper impregnation is an essential process. Today we will share what procedures are used in making the impregnated melamine paper.
1. Mixing the glue (adding the hardener, release agent, penetrating agent, anti-dust agent etc.)
2. First impregnation for MF resin & UF resin mixture
3. First oven drying
4. Second coating for MF resin
5. Second oven drying
6. Cooling and Cutting
The above procedure can be divided into 2 parts – The resin part and the impregnation part. The impregnation process is relatively simple because one advanced melamine paper impregnation line can solve the problem. The only thing that needs to be paid attention to is to ensure uniformity when coating the glue. However, the resin section is not as easy as imagined, only experienced engineers know how to complete it. The impregnation glue for melamine paper is mixed with urea powder, formaldehyde powder, and melamine powder. When the temperature reaches a certain degree, the powder can be melt. Therefore, what percentage of each powder is required and how many degrees is suitable is extremely important. In addition, we also need to add the substrate like hardener, release agent, Penetrating agent, etc. into the glue. The content and rate of these additives are also a science.
The melamine solid content determines the abrasion resistance, moisture resistance, stain resistance of the impregnate decorative paper. Theoretically, the paper impregnated with 100% melamine resin is the best, but pure melamine resin has no viscosity and the melamine paper cannot be stuck on the laminate boards. Thereby, the current melamine decorative paper in the market is all added with urea resin. To ensure high quality, VIIKAN melamine impregnated paper factory usually uses the rate of 90% MF resin and 10% UF resin to produce the overseas orders.
In the meantime, the glue mixing ratio is not a fixed data. It is adjusted according to different regions, climates, raw panels, and applications, For example, the glue ratio for Russian melamine paper buyers and Indian importers are different; the glue additives rate to melamine MDF factories and melamine plywood manufacturers are different; the glue content to furniture paper users and floor laminating production are different. Generally, the resin content is around 130%~150%, volatile content is about 6%~7%, the moisture is 55%~65%. The detailed data depends on the customer’s demand.
VIIKAN not only produces impregnated decorative paper but also non-impregnated decorative paper and melamine paper face boards. We are the expert in the paper printing, impregnation and lamination field. If you want to know the detailed information about the melamine paper impregnation, welcome to contact us, we are pleased to offer help or discuss this subject with you.