Plastic and nonmetallic article shaping or treating: processes – Optical article shaping or treating – Composite or multiple layer
Patent
1996-07-25
1998-11-10
Vargot, Mathieu D.
Plastic and nonmetallic article shaping or treating: processes
Optical article shaping or treating
Composite or multiple layer
264 25, 362 61, 362 831, B29D 1100
Patent
active
058338896
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a method of manufacturing resin components having a light reflector surface as well as to a light reflector component manufactured by the method.
The chief material of parts having a light reflective surface, such as lamp reflectors, has been changed from metal to synthetic resin. At present, most of such light reflector components include a base member composed of a bulk molding compound (hereinafter referred to as BMC) and an aluminum or another metal deposit or coat formed on the light-reflecting surface of the base member.
According to one proposed method of manufacturing a light reflector component, the base member is composed of a thermoplastic resin and the light-reflecting surface of the base member is coated with a metal. This method has been noted because of the good moldability and workability of thermoplastic resins and potential recovery and recycling of the resins.
Another method disclosed in JAPANESE PATENT PUBLICATION GAZETTE No. 3-45688 applies an aluminum sheet previously formed to a shape of reflective surface onto a base member.
In the conventional method of manufacturing a light reflector component by making the base member out of a BMC and coating the light-reflecting surface of the base member with a metal, application of a primer is required prior to the process of coating the base member with a metal. The primer reduces the roughness of the light-reflecting surface so as to improve the reflecting properties and enhance the adhesive properties of the base member with the metal coating.
Thermoplastic coating material is generally used for the primer, which consumes time for the drying process. The liquid primer often causes sags after coating. As shown in FIG. 5, this may result in uneven coating of a primer 7 on the stepped portions and edges of a base member M, thereby lowering the accuracy of the shape of light reflective surface.
In the proposed method of manufacturing a light reflector component by making the base member out of a thermoplastic resin instead of the BMC and coating the light-reflecting surface of the base member with a metal, application of a primer is generally required prior to the process of coating the base member with a metal. This method is also not free from the drawbacks accompanied with the application of a primer as discussed above.
In the method of making the base member out of a thermoplastic resin, it is rather difficult to balance the properties required for light reflector components, that is, the heat resistance, strength, and rigidity, with the light reflecting properties. Variation in composition of the thermoplastic resin has been studied for improving the balance. The technique for enhancing the heat resistance, strength, and rigidity is generally in conflict with the technique for improving the light reflecting properties. No practical technique for settling the balance has been completed yet.
The method disclosed in JAPANESE PATENT PUBLICATION GAZETTE No. 3-45688 forms a thick coating, whose merit is that the light reflecting properties are not affected by the surface of resin components. For the small and simple-contoured components, such as stroboscopes for photography, no problems arise in the process of shaping an aluminum sheet to the light reflective surface. Components having the large and long light reflective surface of complicated shape, such as lamp reflectors of automobiles, have a problem of relatively low accuracy in shape, especially on the stepped portions and edges.
The object of the present invention is to provide a light reflector component manufactured by a simple process to have excellent reflecting properties and good heat resistance and mechanical properties. The first invention is characterized by a method of manufacturing a light reflector component, which includes the steps of: placing a thermoplastic resin film having a shape of light reflective surface closely onto an inner wall of a closed mold; injecting a molten resin into a cavity of the closed mold to form a molded object havin
REFERENCES:
patent: 3337660 (1967-08-01), Bagby et al.
patent: 3839129 (1974-10-01), Neumann
patent: 4154788 (1979-05-01), Hockensmith et al.
patent: 4406045 (1983-09-01), Schweb
patent: 4570203 (1986-02-01), Daniels et al.
patent: 4781870 (1988-11-01), Talbert
patent: 5275764 (1994-01-01), Hettinga
patent: 5413743 (1995-05-01), Prophet
patent: 5614131 (1997-03-01), Mukerji et al.
Fusamoto Akira
Tanikita Masumi
LandOfFree
Method of manufacturing light reflector component and light refl does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of manufacturing light reflector component and light refl, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of manufacturing light reflector component and light refl will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1513436