1. Urea-formaldehyde glue, melamine-formaldehyde glue, and phenolic glue. From the words, it can be seen that formaldehyde participates in the reaction, specifically: urea + formaldehyde + water = urea-formaldehyde glue; melamine + formaldehyde + water = melamine-formaldehyde glue; phenol + formaldehyde + water = phenolic glue.
2. White latex. White latex is a water-soluble adhesive, a thermoplastic adhesive produced by polymerization of vinyl acetate monomer under the action of an initiator. Usually called white latex or PVAC emulsion for short, the chemical name is polyvinyl acetate adhesive. It is synthesized from acetic acid and ethylene to vinyl acetate, and titanium dioxide is added (low-end ones add light calcium, talc, and other powders). It is then made by emulsion polymerization. A thick milky white liquid.
3. Neoprene solution glue. Often called universal glue. In indoor and outdoor decoration, it is often used to paste decorative panels. Due to the use of organic solvents, it has certain toxicity. Apply the neoprene adhesive to the surface of the decorative board, let it dry properly, and it will crystallize instantly after close contact, producing a large initial bonding force. Therefore, compared with white latex, this glue does not need to be clamped for a long time and is more convenient to use.
4. Isocyanate adhesive (MDI). The boards made of it are non-toxic, relatively expensive and rarely used. At present, the big brands on the market have begun to gradually promote this type of plate products.
5. Formaldehyde-free resin. Formaldehyde-free adhesive is a polyurethane adhesive, such as natural resin, synthetic resin, etc. Formaldehyde-free resin is mainly used for this kind of adhesive and is widely used in all aspects of life. This type of adhesive is used in shoes and clothes, and in wood processing of artificial boards. Industry, it is a new type of green and environmentally friendly adhesive. But formaldehyde also exists in nature, and the wood itself also contains formaldehyde to some extent, so there is no absolute zero-formaldehyde board.