DNP Develops Curved Resin Glass for Automobiles

Light with superior transparence, weather and wear resistance

Dai Nippon Printing Co., Ltd. (DNP) has improved the workability of its hard coat transfer film with superior weather and wear resistant properties, and has developed a curved resin glass suitable for use in the sun roofs of automobiles and other applications.


DNP has positioned Living and Mobility as a business growth area, and has made efforts to expand the automobile related business area. Apart from offering decorative film for interior purposes and a viewing angle control film targeting in-vehicle displays, in August, 2015, Tamura Plastic MFG Co., Ltd., which maintains a substantial domestic share in side visors attached to automobile doors, also became a DNP subsidiary. In this way, DNP is moving to strengthen new product development of automobile related components.

In recent years, amidst the rise in consumer awareness regarding the environment and safety, there has also been a trend towards tightening CO2 emission controls, and automobile makers have been pressed to come up with responses. Lighter auto bodies are effective in reducing emissions and improving fuel efficiency, while plastic resin glass, such as polycarbonate, maintains superior impact resistance and thermal insulation properties. In addition, plastic resin glass weighs approximately half the weight of silicic acid based general glass, leading to increased demand for its use in automobiles where weight savings are required.

In order to satisfy these needs, DNP has used original technology to develop a ultra-weather resistant hard coat transfer film for use with resin glass. By transferring the super-weather resistant hard coat to the surface of resins, such as polycarbonates, it has been possible to improve weather resistance, from sunlight and the elements, as well as wear and scratch resistance.

DNP launched the resin glass with this hard coat in February 2016, and it has been placed on the market for industrial uses.

In this latest development, the hard coat layer of the film has been further modified in answer to the needs for curved surfaces in automobiles, and curved surface follow-ability that had been a challenge with existing products also improved as the Company developed a curved resin glass capable of use with the sun roofs of automobiles. As a result of these developments it has been possible to create a bending process capable of producing arcs with a minimum diameter of up to 160mm, or a radius of 80mm, based on original DNP methodology.

[Features of Curved Resin Glass]

  • The film is transferred at the same time as the extruding of the polycarbonate resin, then bent. As a result, it is not only possible to reduce processing costs compared to existing methods that form the hard coat layer by spray coating and so forth following molding, but the manufacturing process can also be shortened.
  • The weight is approximately half that of general silicic acid based glass.
  • It holds transparency equivalent to general glass.
  • It has been possible to create a bending process capable of producing arcs with a minimum diameter of up to 160mm, or a radius of 80mm facilitating use in the sun roofs of automobiles.
  • The newly developed product exhibits superior impact resistance, and as it is more difficult to break compared to ordinary glass, also means that it maintains superior safety features.

Curved resin glass product

Photographic comparisons (weather resistance tests)

 Photographic comparisons (wear resistance tests)

[Forward Looking Developments]

DNP will market the curved resin glass product based on the newly developed film for mobility uses, including automobiles, busses and railway carriages, aiming for sales of 5.0 billion yen in FY 2020.

DNP has positioned Lifestyle and Mobility as a growth area, and aims to provide comfort in a variety of spaces, beginning with housing, offices, schools, commercial facilities, and including automobiles and trains, at the same time as endeavoring to ensure secure information services that can be used anywhere, anytime.

* Product prices, specification and service contents mentioned in this news release are current as of the date of publication. They may be changed at any time without notice.