Status and Development Trend shoes Adhesives

Scientific and technological progress makes the new material constantly emerging, provides a number of useful material for the traditional shoe industry, the application of new materials not only support the development of footwear fashion trends generation function, but also on the performance of adhesives put forward new demands . Therefore, with the development of the footwear industry, but also correspondingly promote technological progress and development of industrial adhesives.

China's shoe industry basic 1.

Footwear production is labor-intensive industries, with the increase in labor costs, the former major footwear producing countries have to shift their production bases in Europe and America to Asia in the early 1980s, when China adopted the reform and opening Qiayu, abundant, inexpensive labor and political stability, both economically active environment to attract a large number of foreign investment in factories, but also spawned a large number of private shoe business. By the late 1980s, China has become the world's largest footwear producer, exporter and consumer. Footwear industry statistics for the most recent figures in 1997, the year China's footwear exports 4.072 billion pairs, for the first time exports exceeded 100 billion mark, reaching $ 10.096 billion.

In recent years, very different from the previous statistical footwear, industry-wide production has not been announced. However, both domestic and foreign footwear authority believes that the current Chinese domestic consumption of footwear in about 2.5 billion pairs, therefore, Based on projections, China's output of 6.5 billion pairs of shoes a year or so, accounting for half of global footwear production . China is a big country shoe, not a shoe-making power, the industry has long been aware of the Chinese footwear industry insight development, must rely on the growing number of transfer to enhance the quality, grade, brand name, increase the added value up, so , our footwear production growth will not be much.

Situation 2 shoe adhesives

Shoe adhesives used in the production of varieties greatly improved production efficiency and product quality. Currently, the type of shoe adhesives are used in many industries, according to the chemical composition of points may include: natural rubber, starch, rubber, neoprene, polyurethane rubber, cellulose gum, polyvinyl formal rubber, EVA plastic, polyolefin plastic , polyester plastic, polyamide plastic, SBS rubber, etc.; divided by form may include: solvent glue, water (milk) glue, adhesives, etc.; according to zoning may include: glue together, sip side glue, rubber coated Baotou , stretch last glue, sticky outsole rubber, stick with the main header glue.

Adhesive shoes

Shoes and cloth shoes in the Whole shoes, shoes are mainly used in adhesive latex rubber and gasoline. Judging from the use of the maximum amount of the glue together the past, the whole fabric glue glue mainly gasoline, for reasons of environmental protection, safety and cost price, and later as a multi-use latex glue together. Many manufacturers to reduce costs in which a certain amount of starch glue, resin emulsions, etc., but still latex category overall. Latex is also used strips of cloth shoes around the bonding process, the whole circumference of the adhesive shoes typically use gasoline glue. Some Jiaoxie Chang in the production of cloth shoes also have the use of gasoline and other parts of adhesive around the practice.

Our 1997 production reached 1.248 billion pairs of shoes, our shoes production is estimated that 14-15 million pairs, the annual consumption of natural latex rubber approximately 30,000 tons of gasoline.

Shoes with glue

Shoes including injection shoes, shoes and seam adhesive Shang shoes. Our 1997 production was 1.644 billion pairs of shoes, the current annual production is estimated at 15-16 million pairs of shoes produced in the largest amount of adhesive is combined glue, glue together the main starch, modified starch or carboxymethylcellulose (CMC) as a raw material. Some manufacturers in order to improve the adhesion of stiff resistance and uppers of shoes, adding a certain amount of cloth in starch gel latex, but still with starch-based. Starch gum, CMC plastic parts are also used shoes uppers, midsole adhesive, such adhesives annual consumption is around 50,000 tons. Adhesive shoes for general use neoprene or neoprene be modified to help end the adhesive, the annual consumption of about 10,000 tons.

Adhesive plastic shoes

For a long time, is not adhesive plastic shoes, because the previous multi-use disposable plastic shoes injection molding or insert a combination of upper belt and shoe soles molding production. In recent years, plastic slippers have begun to focus on style, the upper with printed patterns, symbols, etc., then the soles and uppers with adhesive tape bonding. With EVA, PE and other modified foam sheet production slippers also used adhesive, making plastic shoes has increased in recent years, with the amount of glue. 1997 China's plastics production was 931 million pairs of shoes, the current production of about one billion pairs / year, estimated that about half of the use of the adhesive process, used mainly for polyurethane glue or adhesive modified neoprene, the annual amount of about kiloton .

Adhesives for leather shoes

Shoes, sneakers 90% using craft glue, glue large varieties, including: sip edge polyamide hot melt adhesive glue or gasoline; PU leather and EVA foam sheet composite with modified neoprene; stretch last natural latex, neoprene latex, chloroprene solvent or hot melt adhesive (including a polyester, polyamide, polyolefin-based hot melt adhesive material). EVA midsole and composite fiberboard with neoprene; bag with with neoprene or latex; leather upper, lining bonded with acetal plastic, EVA hot melt adhesive, glue or gasoline neoprene; sneakers upper composite with neoprene glue, hot melt adhesive, hot melt pressure sensitive adhesives which use increased rapidly in recent years; bonding outsole and upper, midsole and outsole with neoprene adhesive, modified neoprene or polyurethane glue.

1997 China's production of leather shoes, sneakers 2.473 billion pairs, yield little change in recent years, estimated that the annual production of 2.5 billion pairs about 1-2 million tons per year of gasoline consumption rubber, latex 2-3 tons, hot melt adhesive 05,000 tons, neoprene (including modified neoprene) 7-8 tons, polyurethane rubber 6-7 tons.

Adhesives used in the shoe business, cloth shoes, shoes of cloth used shoe glue basically self-preparation, the vast majority of the remaining adhesive outsourcing. Currently, the country has produced shoes with adhesive manufacturers more than 200, including more than 100 located in coastal areas, is generally accompanied by a shoe factories base. Guangdong is China's largest footwear production base, the current annual output of 3 billion pairs of footwear export two billion pairs. Guangdong shoe factory is also the country with the largest adhesive, a total of more than 70, most of them are foreign-funded enterprises in these adhesive factory which has about half the production of export goods (and export shoe matching). Guangdong shoes with firm size on the glue has more than 30 levels, for example Haenam light, the South China Sea tyrants, Zhongshan Weiming other companies were more than 10,000 tons of production scale, a few dozens of varieties, including Haenam Light Company production capacity of several tons, and its products into almost all the major footwear production base, leather products production base. Fujian Province, Zhejiang Province, each with about 40 companies producing shoes with adhesive. Jiangsu Province, Shandong Province, Tianjin, each with more than 10 companies producing shoes with adhesive.

Among all kinds of shoes with adhesive to stick gum outsole is crucial, adhesive highest performance requirements, but also footwear companies, manufacturing enterprises are most concerned adhesive adhesive varieties. Currently sticky adhesive outsole whether at home or abroad, basically polyurethane, neoprene-based. In view of the shoe for other purposes adhesives low-tech and technology is more mature, less impact on the industry, therefore, the following main comments sticky rubber outsole.

Adhesive performance outsole

In all shoe adhesives, adhesive performance requirements of external bottom up, so it should have the following properties:

1) of the heterogeneous material having sufficient adhesive strength to adapt to the application of new materials;

2) proper drying speed, good tack to accommodate high-speed production needs;

3) to reach the final (maximum) time is shorter adhesive strength;

4) layer (film) has sufficient resistance to bending properties, heat resistance, water resistance, cold resistance, used for light-colored rubber outsole shoe also requires yellowing resistance, resistance requirements for bonding plasticized PVC material agent;

5) low toxicity, in order to meet the requirements of relevant laws and regulations;

6) sizing process is simple, easy to operate, flexible and adjustable cycle.

Development rubber outsole

The earliest adhesive sticky outsole is used nitrocellulose glue, can only be used leather uppers and leather bottom bonding. With the synthesis of new materials used in footwear, plastic is not suited to the nitrocellulose.

After 1932 there neoprene, rubber-based adhesives have been widely used, it can not only be bonded leather and leather, but also be able to rubber and leather bonded together, in 1939 the company first performed in Germany COMPO rubber sole and leather the bonding process was slow crystallization neoprene, poor tack accordingly, to achieve the ultimate bond strength long time, resulting in the application is not widespread in shoe production. After the 1957 Bayer introduced rapid crystallization neoprene, neoprene adhesive makes widely used bonding outsole possible. The early 1960s, Bayer invented the polyurethane adhesive, neoprene unable to solve the sticky PVC, PU shoe problem. The late 1960s, thermoplastic rubber (TPR) to enter the footwear industry, which is a hard sticky material, then in addition to (halogenated) after treatment with polyurethane adhesive TPR at the end, there had been direct bonding adhesive with SBS SBS (TPR) bottom and vulcanized rubber sole. SBS is a hot glue because activated, the operation inconvenient to use, and its vitality is not long, rubber outsole market has always been occupied by a neoprene and polyurethane. Primer foreign countries choose different varieties, mainly in Western Europe and the United States to use polyurethane rubber, Asian countries, Eastern Europe and Australia, and multi-purpose neoprene. Whether neoprene or polyurethane glue, basically solvent. Organic solvents on rubber, plastic material has a very good penetration, but toxic, flammable, polluting the environment. The early 1970s to the mid-1980s, there have been attempts to study the climax of hot melt adhesive to bond the outsole, however, a serious lack of respect due to the adaptability of the material, adhesive strength and sizing equipment, etc. exist, this attempt has failed to achieve industrialization. 1980s, the German research and development with a polyurethane adhesive dispersion. Mid-1980s, the European launch of solvent-free reactive polyurethane hot melt adhesives, also for various reasons over the years is still not able to achieve industrialization. Therefore, solvent-based dominance outsole rubber is not shaken.

Neoprene Adhesives

The molecular structure of regular neoprene adhesive, cohesive and strong, is a crystalline polymer, with a strong polarity, for a variety of materials with good adhesion properties, widely used. Neoprene adhesive has the following characteristics:

1) without curing has a good cohesion, good initial tack, after being dried glue stick material upon contact there a strong adhesive strength;

2) bonding the soft material, the expansion can alleviate the stress concentration caused by contraction;

3) there are good water resistance, aging resistance, flex, for a variety of materials have good adhesion and reliable performance;

4) solvent-based neoprene manufacturing process is simple, easy to operate, low prices.

Because of neoprene inexpensive, used in the production of footwear outsole with neoprene rubber has long been based. However, since the 1980s, with the shoes with diverse materials, the quality of bonding have higher requirements, the first generation of ordinary neoprene adhesive can not fully meet the requirements of the substrate adhesion, appears the grafted neoprene, the requirements for different materials, there is a dollar graft neoprene, binary, ternary and quaternary copolymers, basically solved the various vulcanized rubber sole, TPR bottom and upper bond issue of . However, for bonding PVC and PU bottom of the die, still have to use PU glue to fix the problem.

The solvent used in the first neoprene benzene, excellent solubility, adhesive properties are more easily controlled, but the considerable toxicity of benzene, after the user in a number of toxic deaths instead of toluene as solvent. Toxicity of benzene toluene, although much smaller than, but still serious poisoning if inappropriate measures the operator and the pollution of the environment. In the 1980s, was once gasoline, ethyl toluene mixed solvent instead of the majority or all instead of Toluene, but increased costs, adhesive performance is unstable, irritating odor heavier workers are not willing to use, plus the time environmental, labor laws and no special emphasis must not use toluene, therefore, no benzene solvents neoprene has not promote open. The mid-1990s, in some footwear production base many times the workers affected by "BTX" poisoning, even after an accident resulting in the death of leukemia, limit the use of "BTX" increasingly strong voice gum. Fujian Provincial Environmental Protection Agency to develop and publish the Fujian Provincial Environmental Protection product approval technical conditions - shoes with adhesive, defined by the product of the raw materials into benzene, halogenated hydrocarbon content; China Green environmental certification mark established by the Committee shoes with adhesive green flag standards, restrictions on the use of BTEX. In this context, there are a number of units produced another free "BTX" of neoprene, polyurethane rubber. Because free "BTX" glue used is higher than the price of a mixed solvent containing "BTX" price, making the finished adhesive 10-20% price increase, many manufacturers, especially small and medium sized shoe still containing "three benzene, "the adhesive, workers poisoning still occur. March 2002, Hebei baigou bags containing business due to "BTX" adhesive (adhesive composition and shoes with plastic almost), plus poor ventilation, or no ventilation, causing many workers appear leukemia, paralysis, the case was disclosed after the death of CCTV, causing the central leadership attaches great importance to instruct relevant departments of the National luggage, footwear and related businesses to investigate the situation with plastic rectification, including "BTX" adhesive has been greatly restricted, some companies the product was ordered out of the market. Therefore, with the enhancement of environmental protection, pollution poisoned intensified, including "BTX" The neoprene will become less and less, or even be eliminated.

The early 1980s to the early 1990s, some of our units have been carried out research chloroprene latex used in footwear production, bonding footwear parts, stretch last, sip side, including heel, etc., but trying to stick outsole efforts have not been successful.