Market and Technical Progress of Polyurethane Adhesives for Domestic Composite Films

1 Introduction

The composite film obtained by adhering together film materials of different properties with an adhesive has many advantages such as high strength, good airtightness, light-shielding property, excellent water and moisture resistance, good heat-sealing property and breakage resistance, and the like. According to actual requirements, it can highlight certain aspects. Therefore, it has been widely used in the packaging industry. At present, the packaging of foods, detergents, and other daily necessities has basically been used as packaging materials with excellent performance and beautifully printed composite films. In the processing of composite films, adhesives are one of the key factors affecting product quality. Currently in the domestic and foreign markets, polyurethane adhesives have become the main adhesives for composite film processing with its excellent overall performance. This article will discuss the market conditions, prospects and technological development trends of polyurethane adhesives for composite films.

2 Domestic market conditions

In the domestic adhesive market, polyurethane adhesives are one of the more rapidly developed varieties. The use of polyurethane adhesives in composite film manufacturing ranks second only to the footwear industry. According to the statistics of China Polyurethane Industry Association, in 1998, the annual amount of polyurethane adhesive for composite films was 0.8 million tons, accounting for about 7.8% of the total amount of polyurethane adhesives. In 2000, the annual usage of polyurethane adhesives reached 15,000 tons. The total dosage is about 12%. In 2002, the annual dosage was nearly 20,000 tons, accounting for about 13% of the total dosage. It is estimated that by 2005 it will use more than 30,000 tons, and the estimated proportion is about 15%.

There are many domestic manufacturers of polyurethane adhesives for general-purpose composite films, among which are Zhejiang Huangyan Ink Factory, Beijing Chemical Industry Research Institute, and Henan Chemical Research Institute. In addition to other manufacturers, the current output can already meet domestic demand. Market demand, and in the past two years showed the phenomenon of oversupply; and in the resistance to cooking adhesives, the size of the manufacturers only Beijing Chemical Industry Research Institute, Dalian Light Chemical Research Institute and a few other, the production capacity still can not meet the domestic Demand, most of the products rely on imports. China Polyurethane Industry Association at the 2002 annual meeting made it clear that such research and development work should be strengthened to achieve product performance to the same level in foreign countries, and strive to build 1000t a-1 production facilities, and gradually meet the growing market demand.

3 Domestic technological progress

The production technology of polyurethane adhesives for domestic composite films was improved in the 1980s based on the introduction of foreign technologies. With the in-depth research work of domestic scientific research units and the improvement of related raw material production processes and technology, the quality of products has also been improved. Great improvement. Its technological development process has gone through the following steps:

3.1 High solid content of products

In the early market, adhesives were mainly based on 30% and 50% solids, but as the country’s environmental protection requirements became more stringent, by 2002, the varieties sold in the market had been mainly 75%. Solid content products, only some products with 50% solid content, 30% solid content products are few.

3.2 Localization of cooking resistant adhesives

At present, domestic retort-type adhesives are still mainly dependent on imports, but some of the company's products have occupied a certain market share. For example, the product performance of Beijing Research Institute of Chemical Industry has reached a higher standard, and it is produced and sold on a scale; the composite film produced from the XK 908 cooking resistance adhesive developed by the Dalian Light Chemical Research Institute can withstand 121°C at 35 minutes and has been built to 300 tons. The a-1 production line; Dawning Chemical Research Institute has also developed products that can achieve the level of Japan's Toyo Ink AD 502, and is undergoing pilot test; meanwhile, many units such as Henan Chemical Research Institute and China Ordnance Industry No. 53 Research Institute are also Conduct related research work. It is estimated that in the next few years, the market share of homemade cooking-resistant adhesives will gradually increase.

3.3 Solid content 100% adhesive research

Due to the requirement of environmental protection, adhesives with 100% solid content were developed in foreign countries in the 1970s. The products were immediately put into use in the 1980s. At present, the amount of adhesives has accounted for more than 50% of the total.

Due to reasons such as composite machinery and production technology in China, research work has been carried out late. Prior to 1995, there was only one solventless laminator. In recent years, it has developed rapidly. By the year 2002, there were more than 20 solvent-free laminating machines in China, and the demand for 100% solids adhesives also increased year by year. The Beijing Chemical Industry Research Institute has produced technology through the introduction of German Henkel company's technology, and this type of product has been put on the market. We believe that other domestic companies and research institutions should quickly carry out relevant research and development work in order to have a place in the international market.

3.4 Research of Waterborne Polyurethane Adhesives

Water-based polyurethane adhesives for composite films are also one of the development directions in the future, but the current development trend lags behind 100% solids adhesives. Some large Western chemical companies such as BASF have conducted a lot of research work in this area. They have studied in detail the various performance differences between composite films made from waterborne and solvent-based polyurethane adhesives, and have obtained some satisfactory results. result. However, its progress in practical applications is still relatively slow. Many domestic research institutes are engaged in the development of water-based polyurethane adhesives, but there is no official report on the application of composite film production.

4 Conclusion

Polyurethane adhesives for composite films are one of the more rapidly developed adhesives. Domestic related companies and research institutions should actively pay attention to the development of domestic and foreign markets and technologies. In the case that the ordinary adhesive market is saturated, it is resistant to cooking. High-value-added products such as plastics with 100% solids content have been put into more research and development work to further improve the technological level and product quality of related industries.

Source: China glue network