JPH0386508A - Manufacture for windowpane with frame body - Google Patents

Abstract

PURPOSE:To enable mass production of molded products whose external appearance is favorable, by a method wherein a surface part and rear part of a frame body or a molding are made respectively with molding methods, which are different from each other, that is, an extrusion molding or an ordinary injection molding and foam molding. CONSTITUTION:A surface side part 1 of a frame body which is, for example, injection-molded or extrusion-molded separately is arranged within elastic top and bottom forces 4, 5, for example, of silicone rubber elastic molds so that the surface side part becomes the surface side of the frame body. Then a windowpane with a frame is manufactured by molding a rear side part 2 where a glass plate 3 and a surface side part are integrated with foam molding by casting resin stocks, through which the frame body made of resin is moldable with removal of paper and the foam molding, into the top and bottom forces 4, 5, in also a circumferential part of the glass plate 3 also. Vinyl chloride resin, polyamide resin, polystyrene resin, polypropylene resin, polyethylene resin containing, for example, a foaming agent are available as a foaming resin material performing injection molding of the rear side part with the foam molding. The frame body is molded integrally with the circumferential part of the glass plate 3 with the extrusion molding or the ordinally injection molding, in the surface side part of the frame body becoming a polyurethane design surface.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing frame-attached window glasses such as frames and moldings used as vehicle, industrial, and architectural window glasses.

[Prior Art] A method for manufacturing window glass in which a frame body such as a frame body or a molding body is integrated with a glass plate is to set the glass plate in a mold and inject resin into the mold to integrally mold the window glass. Are known. There are roughly two types of resins to be injected at this time. One is the so-called RIM method, in which two types of reactants, such as urethane, are simultaneously injected and mixed to react and form a resin within a mold. In the RIM method, the pressure inside the mold is low, on the order of several kg/cm2 to 10 kg/cm", so the glass plate is difficult to break. Furthermore, a fairly thick elastic material is used in the sealing part to prevent dimensional errors in the curvature of the glass plate. However, on the other hand, (
1) Material prices are high, (2) Products need to be painted to compensate for poor weather resistance of the materials, and (3) demolding time is long due to reaction within the mold, both in terms of cost and productivity. It has disadvantages and is not widely used. The other method is to heat and melt a thermoplastic resin such as vinyl chloride and then inject it, which is widely used because of its good cost and productivity. However, since molten resin is injected, the resin temperature is 180℃ or higher and the pressure is 300kg/cm.
It is often used under the above conditions.

Therefore, when laminated glass or double-glazed glass is used as the glass plate set in the mold, the heat and pressure of the injected resin may cause the glass plate to crack, interlayer film (laminated glass), sealant ( This may cause problems such as deterioration or damage to double-glazed glass. In an attempt to solve the above-mentioned problems, using a resin composition that melts at a relatively low temperature for thermoplastic resin, or a resin composition that has low viscosity when melted, has extremely good fluidity, and can be injection molded at low pressure, is necessary as a wind molding material. Another problem occurred in that basic physical properties such as tensile strength, elongation, and cold resistance deteriorated significantly.

Therefore, with conventional technology, the method of integrally molding moldings on laminated glass such as automobile or vehicle windshields, or double glazing used in various types of vehicle and industrial windows is limited to the RIM method. ,R
There has been a desire for a method that can be manufactured more cheaply and efficiently than IM.

[Problems to be Solved by the Invention] An object of the present invention is to overcome the above-mentioned drawbacks of the prior art.

[Means for Solving the Problems] The present invention has been made to solve the above-mentioned problems,
In a method of placing a glass plate in a mold and integrally molding a frame, a seal, etc. around the glass plate using injection molding, only the front side, which is the design surface of the frame, is placed in a separate mold. Manufacturing of a window glass with a frame body, characterized in that the glass plate is injection molded in advance, placed together with a glass plate in an elastic mold having a predetermined cross-sectional shape of the frame body, and at least the remaining back side portion is formed by foam molding. It's a method.

In the present invention, the foamable resin material for injection molding the back side of the frame in a foamed ffl shape includes, for example, vinyl chloride resin containing a foaming agent, polyamide resin, polystyrene resin, polypropylene resin, polyethylene resin, and polyurethane resin. The front side of the resin frame, such as the frame, molding, weather strip, etc., which forms the surface, is integrally formed around the glass plate by extrusion molding or ordinary injection molding. It is molded in a separate mold for the front part.

The mold used in injection molding is a conventionally used general mold made of metal such as cast iron or stainless steel. In addition, silicone rubber, ethylene propylene rubber, urethane rubber, silicone rubber, ethylene propylene rubber, urethane rubber, Rubber elastic bodies such as nitrile rubber and various synthetic resin elastomers are used. Regarding the structure of the mold, not only is the entire mold made of the above-mentioned rubber elastic body or synthetic resin elastomer, but also the rubber elastic body or synthetic resin elastomer is used partially on the surface that contacts the glass plate. It can also be a type of structure. Furthermore, these elastic molds may be used for both the upper and lower molds. The mold for the front part is the usual gold M type for bonito fish, and a synthetic resin mold can be used, and an elastic mold can be used only for the front part.

For example, as shown in FIG. 1, a front part 1 of a separately injection-molded or extrusion-molded frame is placed in upper and lower elastic molds 4 and 5, for example, a silicone rubber elastic mold, so that the front part becomes the front side of the frame. At the same time, the peripheral parts of the glass plate 3 are placed in the upper and lower molds 4.5, and a resin frame is formed by foam molding.A resin raw material is injected and the glass plate 3 and the front part are integrated by foam molding. The resulting back side part 2 is molded to produce a window glass with a frame.

[For production]

Glass plates such as laminated glass and double-glazed glass, which have the same strength as ordinary unreinforced glass plates, are easily broken by mold clamping even if there is a slight curvature error during the glass plate bending process. Furthermore, during injection molding, it is easy to crack due to heat and high injection pressure, and at the same time, problems such as deterioration and alteration of the interlayer film and sealing material occur. Furthermore, even with tempered glass, when the shape is complicated and deep bending is performed, the bending accuracy is poor, the curvature error becomes large, and cracks are likely to occur during mold clamping.

Therefore, regardless of whether the glass is reinforced or unreinforced, in order to prevent the glass from breaking during mold clamping, it is necessary to use a mold that has elasticity that can absorb the curvature error of the glass plate. However, such an elastic mold inevitably has low strength and cannot withstand high injection pressure, so it can only be molded at low injection pressure. On the other hand, it is necessary to mold laminated glass or double-glazed glass at a low injection pressure in order to prevent glass cracking and deterioration and deterioration of the interlayer film and sealing material during molding.

Foam molding is a method for molding thermoplastic resin at low injection pressure. Although foam molding allows the use of elastic molds, the surface finish of molds made of rubber or synthetic resin elastomers is not always sufficient, and small scratches may occur on the mold surface during repeated molding. Defects such as cracks and chips are likely to occur, and this is reflected in the design of the molded frame or molding frame, resulting in product defects.

As in the present invention, the front side corresponding to the design surface is molded in advance by extrusion molding method or injection molding method using a metal mold, and this is inserted into an elastic mold together with a glass plate and only the back side is foam-molded. Low-pressure molding becomes possible without causing product defects such as. This results in
It is possible to prevent glass from breaking during mold clamping and molding, and also to prevent deterioration and deterioration of the interlayer film and sealing member.

Furthermore, as a secondary effect, the molded part on the front side acts as an elastic body, so that it is also possible to use a metal mold as a mold that comes into contact with the front side during foam molding.

[Effect of the invention J] By manufacturing the front side and back side of a frame body such as a frame body or a molding using different molding methods, that is, extrusion molding or ordinary injection molding and foam molding, as in the present invention, Low-pressure molding using thermoplastic resin enables mass production of molded products with good appearance. Furthermore, this can prevent glass breakage during mold clamping and molding, as well as deterioration and deterioration of interlayer films and sealing members when laminated glass or double-glazed glass is used.

Furthermore, the weight of the frame body, molding, etc. can also be reduced by foam molding.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view showing a mold used in one example of the present invention. 1...Front side part of the frame (injection molded part) 2...Back side part of the frame (foam molded part) 3...Glass plate 4...Upper mold 5...Lower mold diagram

Claims (1)

[Claims] A method in which a glass plate is placed in a mold and a resin frame is integrally molded around the glass plate using an injection molding method, in which only the front side, which is the design surface of the frame, is molded by extrusion molding or injection molding. 1. A method for producing a window glass with a frame, which comprises placing the glass plate together with a glass plate in an elastic mold having a predetermined cross-sectional shape of the frame, and forming at least the remaining back side portion by foam molding.