Bonding materials are one of the main materials for modern bookbinding. There are roughly four types of adhesive materials used in this book, including plants, animals, natural resins, and artificial synthetics. The plant starch bases used in the early days have basically been eliminated and replaced by artificial synthetic resins. At present, the use of cementitious materials is: synthetic resin: 80%, animal bone glue 10%, rosin in the animal category, gelatin in the animal category, and egg and egg glue account for 10%. Among them, the rapid development, more varieties are synthetic resin bonding materials, and now are commonly used in the following categories.

(1) Polyvinyl acetate adhesive (PVAC)

The adhesive made of vinyl acetate monomer is a cold glue. Mainly used for bonding paper, cardboard, cardboard, paper and fabric composites.

(2) Polyvinyl alcohol gel (PVA)

White floc or powdered polymeric thermoplastic adhesive. Its use range is the same as that of polyvinyl acetate.

(3) ethylene vinyl acetate copolymer hot melt adhesive (EVA)

Commonly referred to as EVA hot melt adhesive, it is a kind of hot-melt adhesive material. It is also the main adhesive material used in China's post-press binding. Its annual usage is about 14,000 tons, and it is mainly used for paperback binding and bag cover. The hot melt adhesive can be used by heating and melting to a certain temperature. The higher the temperature is, the higher the fluidity is, and if it is lower than the melting point, it becomes a solid. When using the glue temperature is strictly required, only in the standard temperature and humidity control, can get a good bonding effect. It is an adhesive suitable for modern production.

(4) Vinyl Acetate-Emulsion Adhesive (VAE)

It is a high-strength cold water-soluble adhesive, milky white, is a water dispersion system of vinyl acetate and ethylene copolymers, can bind a variety of paper, cardboard, cardboard and so on. It can be used for the bonding of paper and PVC. It is an ideal material for hardcover lining.

(5) Acrylate adhesives

A cold water soluble material derived from the copolymerization of acrylate and styrene. It has strong viscosity and strength and is mainly used for the bonding of paper and PVC and various films (such as BOPP film, PET film, etc.).

(6) Polyurethane (PUR) Adhesives

Polyurethane is a new type of adhesive material, which is divided into two types: cold water-soluble and hot-melt; bookbinding is mainly used hot melt adhesive, used in the binding production line on the linkage production line, can also be used for coating process. Compared with EVA hot melt adhesives, PUR has many advantages, such as high viscosity, low usage, good adhesive effect, and especially good flexibility of the adhesive layer. It is easy to read books and articles that are bonded with them, and it is not easy to drop pages or disperse them. The development direction of binding materials for book binding after printing.

Nowadays, some advanced countries have used PUR glue mostly in bookbinding, especially hardcover books. There are also a small number of manufacturers in China that have been used in the paperback binding line, and the usage will gradually increase.

Author / Wang Huaizhu Source: Printing Technology