Nippon’s innovation: reducing the curing temperature of automotive coatings from 140 to a minimum of 80

Nippon Paint (China) Co., Ltd. published an invention patent “One-component low-temperature cross-linked water-based paint and its preparation method” not long ago this year. The patent abstract shows that the invention provides a one-component low-temperature cross-linking water-based coating, which endows the coating with high elasticity and high elasticity through the cross-linking action of water-based acrylic resin, water-based polyurethane, elastic resin and one-component cross-linking agent. The dual characteristics of cross-linking provide a one-component low-temperature cross-linking water-based coating system that is especially suitable for original automobiles. The coating is used in the original automobile factory, which can meet the requirements of low temperature curing while taking into account other properties, and reduce the curing temperature of the original automobile coating from 140°C to 80-100°C.

In recent years, with the increasingly strict national and local environmental protection laws and regulations and the improvement of people’s awareness of environmental protection, energy saving and emission reduction technology has become an important direction of today’s development, and its development has prompted all walks of life to actively research and develop new materials to meet the increasingly stringent requirements. laws and regulations and environmental requirements. The auto industry shows the same obvious trend, and new opportunities and challenges emerge as the times require with the booming development of the auto industry. At the same time, in order to ensure sufficient cross-linking and curing of the coating system, the traditional baking conditions for automotive coatings are 140-160°C for 20-30min. The resulting high energy consumption and high emissions are unavoidable in traditional processes. Therefore, hard wax manufacturers, low-temperature (80-100°C) cross-linked coatings and coating processes with high performance, low emissions, and low energy consumption have received more and more attention.

At present, the research on automotive low-temperature cross-linking coatings mainly focuses on low-temperature two-component cross-linking systems, in which two-component polyurethane technology is mainly used to achieve cross-linking. However, the two-component polyurethane system cannot be stored for a long time after mixing due to the short pot life after mixing. Therefore, in the process of using the original car factory, it must be required to transform the original one-component paint feeding pipeline, thereby greatly increasing the operating cost of the car manufacturer. At the same time, since the two-component crosslinking agent itself is sensitive to moisture and humidity, special attention should be paid during storage and circulation to prevent the deterioration and failure of the crosslinking agent. Therefore, one-component automotive low-temperature cross-linked coatings have their natural advantages of stability and ease of use.

However, the low-temperature cross-linking process of one-component automotive coatings has not yet been realized, and the main limitation lies in the stability and curing effect of the low-temperature one-component cross-linking agent. At the same time, in the existing traditional technology, it is difficult for one-component water-based coatings to be cured at low temperatures while meeting the performance requirements of original automotive coatings. Therefore, the invention aims to solve the defects in the low-temperature cross-linking curing process, improve the stability and low-temperature cross-linking degree of the one-component cross-linking agent, and at the same time meet the performance requirements of the original automobile coatings.

It is reported that the purpose of the invention is to provide a one-component low-temperature cross-linked water-based paint, which can be used in the original automobile factory. The coating can meet the performance requirements of the original automobile coating under the condition of low temperature baking. Aiming at the particularity of low-temperature cross-linking of original automobiles, the invention provides sufficient cross-linking density and ensures paint film resistance through the cross-linking action of water-based acrylic resin, water-based polyurethane, elastic resin and low-temperature cross-linking agent. At the same time, because the elastic resin has the characteristics of small molecular weight, high hydroxyl content, strong fluidity, and strong chain stretchability, it can provide good leveling without reducing the crosslinking density during the low temperature baking process, thereby ensuring the paint The elasticity of the film and increase the adhesion between paint layers. Therefore, the prepared water-based paint is a low-temperature cross-linked paint especially suitable for the original automobile factory. The water-based low-temperature cross-linked coating provided by the invention has the performance of matching the traditional high-temperature automobile original coating while providing decorative effects, and has extremely low VOC and long-term stability, thereby ensuring good construction applicability.

Nippon Paint entered the Chinese market in 1992, with a wide range of businesses covering architectural coatings, commercial wood coatings, automotive coatings, powder coatings, general industrial coatings, coil coatings, marine coatings and auxiliary materials. At present, Nippon Paint has set up automotive coatings divisions or production bases in Shanghai, Guangzhou, Langfang, Chengdu and other places, and has established a professional automotive coatings company in Shanghai – KAI Bai Nippon Automotive Coatings (Shanghai) Co., Ltd. Several production bases have built automotive coating production lines. It is worth mentioning that Nippon Paint China also entered the field of passenger car coatings through the acquisition of Xinzhanwang in November 2017.

As a company that can provide complete coating systems for automobiles, Nippon Paint has three branches in China’s automotive coatings market: Auto Paint Division, Auto Refinish Division, and KAB In the interior and exterior decoration market, the products cover car body pretreatment coatings, electrophoresis, intermediate coatings, color coatings and parts coatings. Customers include Toyota, Honda, Nissan, Mazda, Geely, Changan, Great Wall, Chery, FAW, SAIC, Dongfeng, BAIC, Volkswagen, Xiamen Golden Dragon, Xiamen Golden Brigade, Shanghai Shenlong, Yutong, etc.

At present, the market share, market competitiveness and brand influence of Nippon Paint China’s automotive coatings business are all at the forefront of the domestic industry. According to the financial report, the sales revenue of Nippon China’s automotive coatings business from 2015 to 2021 was 1.65 billion yuan, 1.800 billion yuan, 2.050 billion yuan, 2.493 billion yuan, 2.139 billion yuan, 2.065 billion yuan, and 2.2456 billion yuan. According to the “2021 Top 25 Chinese Auto Paint Brands” list released by “Tujie”, Nippon Paint ranks No. 4 in the production list, and at the same time, it has entered the top 10 Chinese auto original paint brands and China’s passenger car original paint brands. Top 5 and China’s top 5 commercial vehicle coatings brands three sub-lists.

It is worth mentioning that although the demand in China’s auto market has been sluggish in recent years, Nippon Paint is still increasing the production capacity of China’s auto coatings. Among them, the Nippon Paint China Automotive Coatings Eco-Industrial Park project started construction in Tianjin Nangang Industrial Zone in July last year. After the completion of the project, the annual output of the project is 73,000 tons of water-based industrial coatings, 20,000 tons of oil-based industrial coatings, and 40,000 tons of industrial coatings per year. tons of resin; in addition, Nippon Paint China also plans to invest in the construction of automotive coatings projects in Qingyuan, Guangdong, Kaifeng, Henan and other places.

In order to better expand China’s automotive coatings market, Nippon Paint Co., Ltd. and Tianjin Economic and Technological Development Zone signed a cooperation agreement on the “Nippon Investment Co., Ltd. Nippon Automotive Coatings China Headquarters Project” in Shanghai last November. It is reported that after the establishment of the headquarters, it will undertake the functions of investment, global R&D and comprehensive management of Nippon Paint in China. After it is put into production, it is expected to have an average annual operating income of 1.6 billion yuan and an average annual tax payment of about 150 million yuan.

It is worth mentioning that Nippon Paint also announced on November 2 last year that its merged subsidiary Nippon Paint Co., Ltd. (NPAC) signed an equity transfer agreement with Toyo Holdings Co., Ltd., and planned to acquire China at a price of 5.9 billion yen. The remaining 40% of the five automotive coatings companies make them wholly-owned subsidiaries of NPAC. Nippon Paint said that through this transaction, we will consolidate and integrate China’s automotive coatings business to increase our market share.