1. Field of the Invention
The present invention relates to a functional product, particularly to a functional product excellent in durability and appearance.
2. Discussion of Background
Conventionally, a Low-E glass (low emissivity glass), or a heat ray shielding glass (normally called a heat ray reflecting glass) wherein a multi-layer film is formed on a glass substrate having a large area by the magnetron sputtering method, has been employed. Since the glass employed in construction is excellent in energy conservation effect and design performance, it has considerably been prevailing in recent years.
The Low-E glass made by a sputtering method, is normally composed of three layers of an oxide film/a silver film/an oxide film. Since this type of Low-E glass employing silver, has a problem in durability, it cannot be employed in a single plate glass, and is used in a form of double glazing or laminated glass. For a windshield glass and a rear glass of an automobile, a low emissivity glass coated with a three-layer film composed of zinc oxide film/silver film/zinc oxide film made by a sputtering method on the side of a surface thereof for adhesion to form a laminated glass, is reduced into practice.
The heat ray shielding glass is produced by a continuous production line including steps of cleaning the substrate, sputtering for film formation and post-cleaning. In recent years, mounting of the substrate on the line and withdrawal of the product from the line tend to be automated.
However, the Low-E glass employing silver is poor in the scratch resistance of the film, and a due care is required in its handling until it is assembled into a double glazing or laminated glass. Therefore, it has been difficult to automate its production. Specifically, in a usual automatic production, a resin powder is usually sprayed between the glass products to avoid adhesion of the glass products to each other at the time of withdrawal of the glass products. However, in the case of the Low-E glass employing silver, the film surface is likely to be scratched by this powder, since the scratch resistance of the film is poor. Accordingly, with the Low-E glass, it has been difficult to automate the withdrawal of the glass products, and such withdrawal has been manually carried out, and it has been common to insert paper or the like instead of the powder between the glass products. Therefore, it has been difficult to shorten the production time, and the production cost has been substantial.
It is an object of the present invention to solve such problems and to provide a Low-E glass employing silver, whereby the scratch resistance of the film surface is improved, and withdrawal of the glass products can be automated.