Melt glue is a new type of adhesive developed and applied in the world in recent years. The product itself is solid, easy for packaging, transportation, storage; solvent-free, non-polluting, non-toxic type; and the production process is simple, high added value, viscosity and strength, speed and other advantages favored.

status quo

Since the mid-1970s, China began to research hot melt adhesives. At present, major types such as EVA, polyamide, polyester, SBS, SIS, and polyurethane can all be produced, and some have already reached a certain scale.

In the past five years, the domestic hot melt adhesive industry has entered a period of rapid development. The output of hot-melt adhesives grows at a rate of about 25% per year. In 2000, the annual output of hot-melt adhesives in the country exceeded 40,000 tons, and more than 60 production companies were involved. The total output value of the market is about 700 million yuan. The scope of application of hot-melt adhesives is also expanding, from traditional sanitary products, packaging, bookbinding and other fields to clothing, tapes, footwear and even refrigerators, cables, automobiles and other industries.

Hygiene products for sanitary products

This type of hot melt adhesive is mainly used in women's sanitary napkins, baby diapers and elderly patients with lost products. It is currently the most widely used category and tops the list with a ratio of 32.7%. Nearly 30 domestic manufacturers produce hot-melt adhesives for sanitary products. Among them, National Starch, Huida, and Fule occupied the majority of hot melt adhesives for high-end sanitary napkins and all share of hot melt adhesive for diapers.

Hot melt adhesives for the apparel industry

China's textile industry has always been in a relatively developed position. In the ancient times, there was a famous "Silk Road." In recent years, the use of hot melt adhesives for garments and adhesive liners has also rapidly expanded with the increase in the quality requirements of garments and the large increase in apparel exports. It can be predicted that there will be more demand in this area after joining the WTO. There are many types of hot-melt adhesives such as PA, PES, EVA, and PE. However, high-grade hot-melt adhesives (mainly PAs) that are really high-temperature-resistant and washable are not yet available in China.

Glue stick with hot melt adhesive

Hot melt glue sticks are products that have been developed in recent years, but they have developed rapidly and have been recognized and mastered by many people. It uses electric heating to melt the glue. The glue extrudes and sticks the adherends from the gun mouth. The operation is convenient, the curing speed is fast, and the adhesive strength is reached after a few seconds. It has been applied to the splicing of floorboards, production of arts and crafts, insulation of household appliances, decoration of plaques, and production of speakers. Mainland China and Taiwan Province have global leadership in this industry.

Book binding wireless hot melt adhesive

This kind of glue was used earlier in China, but due to the limited price of books, its application has been very sluggish. Low adhesive strength, brittleness at low temperatures, and short life span are also issues that afflict vast numbers of booksellers. In recent years, with the rapid economic development, more people have begun to move towards books, and this situation has improved.

Hot melt adhesives for other industries

The use of plastics for footwear, construction and electrical appliances is still rare in China, but with the entry of China into the WTO, the international trend of hot melt adhesives will surely drive demand in this area. As a manufacturer must realize this and make corresponding countermeasures.

Although the application of hot-melt adhesives continues to expand, domestic development and production in this area is also growing, but there are too many domestic hot-melt adhesive companies and the scale is too small. More than half of the more than 60 hot-melt adhesive manufacturers have annual sales of less than 500 tons, and there is almost no scale benefit. At the same time, the utilization rate of the total production capacity of hot-melt adhesives companies is only about 50%, and the production capacity is in excess, resulting in fierce market competition. The low level of price war is not only unfavorable for enterprises to carry out technological innovation, but also undermines manufacturers' production enthusiasm.

Direction of development

Modification of existing species

The existing varieties are modified by blending and grafting to improve the performance of the hot melt adhesive. For example, stabilizers are used to prevent oxidation; tackifiers improve bonding strength; paraffins reduce viscosity to change surface properties; various fillers can increase viscosity, melting point, and bond strength.

Study the variety and dosage of various compounding agents and optimize the formulation to meet different requirements.

Accelerate the development of new products

Curing hot melt adhesives and functional hot melt adhesives are currently two major new products on the market. The former main feature is to improve the hot-resistance characteristics of hot-melt adhesives, increase the softening point to more than 120 °C, thereby expanding its scope of use; functional hot-melt adhesives are for specific occasions, can achieve specific functions to meet the needs of various aspects of a Plastic. Such as water-soluble or dispersible hot melt adhesive, hot melt sealant, hot melt pressure sensitive adhesive and so on.

Develop high performance hot melt adhesive

In addition to the more common EVA and TPR hot-melt adhesives, companies should also focus on research and development of some of the high-tech hot melt adhesives currently used in the West and have huge potential for application, including: reactive hot melt adhesives, water-dispersible heats Melt, high-grade PA hot-melt lining rubber and high-strength hot melt pressure sensitive adhesives. At the same time, relevant domestic raw material manufacturers should also recognize the potential of hot melt adhesive industry, speed up the increase of the localization rate of raw materials, and reduce the loss of foreign exchange caused by large amounts of imported raw materials.

As a national macro-control, one should strengthen industry management and technical supervision, complete national or industry quality standards as soon as possible; Second, strengthen market norms, carry out orderly competition, and urge the industry to develop in a benign direction.