JPH0444887B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a molding or gasket around the periphery of sheet glass for vehicles or architecture, and in particular, a method for forming a molding or a gasket around a sheet glass for use in vehicles or architecture, and in particular a method for forming a synthetic resin raw material into a mold in which the sheet glass is placed by a reaction injection molding method. This invention relates to a method of forming a molding or gasket around the periphery of a glass sheet by injection.

BACKGROUND OF THE INVENTION Synthetic resin moldings and gaskets (hereinafter collectively referred to as moldings) are usually attached to the periphery of sheet glass for vehicles such as automobiles or sheet glass for construction for the purpose of decoration or sealing. This synthetic resin molding is usually attached to a glass plate by using a pre-formed molding and attaching it to the periphery of the glass plate by means of gluing, fitting, or the like. However, this conventional method is complicated and not economical because it requires molding in advance and attachment to the sheet glass. Further, it has been difficult to manufacture moldings having complicated shapes or moldings with uneven patterns formed on the surface using conventional molding methods such as extrusion molding.

As a result of various research studies on methods for attaching synthetic resin moldings to sheet glass for vehicles or construction, the inventor directly molded a synthetic resin molding around the glass sheet using a reaction injection molding method, thereby creating a synthetic resin molding. 1 sheet glass with attached
We found a way to manufacture it in a process. In this method, molding of the synthetic resin molding and attachment to the peripheral area of the glass sheet are performed simultaneously, so the number of steps is omitted and economical efficiency is improved. Furthermore, by molding the synthetic resin around the periphery of the sheet glass, it becomes possible to easily mold moldings with more decorative and complex shapes. The present invention is a method for producing a sheet glass in which a molding made of polyurethane resin is formed on the periphery of a sheet glass by integral molding, that is, a method for manufacturing a sheet glass in which a molding made of polyurethane resin or a gasket is formed on the periphery of sheet glass for use in vehicles or architecture. The inner surface of the sheet glass is placed in a mold coated with a release agent, the mold is closed, a cavity space is formed by the peripheral surface of the sheet glass and the inner surface of the mold coated with the release agent, and then polyurethane resin is molded by reaction injection molding. Forming a molding or gasket made of polyurethane resin around the periphery of a sheet glass for vehicles or architecture, characterized in that raw materials are injected into the cavity space and solidified, and after the polyurethane resin has solidified, the sheet glass is taken out from the mold. It's a method.

An example of the method of the present invention will first be explained using the drawings. FIG. 1 is a partial sectional view of a closed mold with a glass plate placed inside. The mold consists of an upper mold 1 and a lower mold 2, and a glass plate 3 is located between the upper mold 1 and the lower mold 2. The peripheral portion of the glass plate 3 is composed of an upper peripheral surface 4, a lower peripheral surface 5, and an end surface 6, and the widths of the upper peripheral surface 4 and the lower peripheral surface 5 are designated as a and b, respectively, as shown. As described later, there are cases where the molding is not formed on the entire peripheral area of the glass sheet, so the surface where the molding is formed in the peripheral area is called the molding forming surface, and the peripheral area of the glass sheet including the surface where the molding is not formed in the peripheral area is called the molding forming surface. The other surfaces will be referred to as non-molding surfaces.
Therefore, the peripheral upper surface 4, peripheral lower surface 5, and end surface 6 in the figure are molding forming surfaces, and the other surfaces 7, 8 of the sheet glass
is the non-moulding surface. The mold inner surface surrounded by the inner surface 9 of the upper mold 1, the inner surface 10 of the lower mold 2, and the molding forming surface of the sheet glass that are not in contact with the non-molding forming surface becomes a cavity space 11, and in this space 11 there is a parting line 12 between the upper and lower molds. The synthetic resin raw material is injected through the injection hole provided in the.

In the present invention, a mold release agent is applied in advance to the inner surface 9 of the upper mold 1 and the inner surface 10 of the lower mold 2 facing the cavity space 11. In some cases, a mold release agent is also applied in advance to the surfaces of the elastic bodies 13 and 14 having sealing properties, which will be described later, and which face the cavity space 11. Furthermore, this elastic body 13,
A mold release agent may also be applied to the surface of 14 that contacts the glass plate 3, and if the elastic bodies 13 and 14 are not fixed to the inner surface of the mold, the mold release agent is also applied to the surface that contacts this mold. You can leave it there. As a mold release agent,
wax-based mold release agent, silicone oil-based mold release agent,
Fluorine-containing mold release agents and other mold release agents can be optionally employed. As will be described later, the synthetic resin raw material injected into the cavity space 11 reacts and solidifies in this cavity space to become a synthetic resin. Many of these materials adhere more firmly to the mold surface than molten synthetic resins, rubber, etc. used in normal injection molding. Therefore, unless the non-stick properties of the mold surface are improved, sufficient mold release is likely to be difficult.

In FIG. 1, it is undesirable that the synthetic resin raw material enters from the cavity space 11 into the contact surfaces between the non-molding surfaces 7 and 8 of the glass plate 3 and the upper mold 1 and the lower mold 2. Therefore, it is preferable to adopt a method of sealing this part. One method is to combine the non-molding surfaces 7, 8 of the glass sheet 3 with the upper mold 1.
And/or there is a method in which an elastic body having sealing properties is provided on the contact surface with the lower die 2. This elastic body may be a thin film or relatively thick. Moreover, this elastic body may be attached in advance to the inner surface of the mold, or may be attached to the non-molding surface of the sheet glass by adhesive or the like. Of course, it is not necessary to attach it to both of them in advance, but it may be something that can be fixed by compression between the sheet glass and the mold. The elastic body having this sealing property can be present over the entire non-molding surface, but it is often sufficient to have only the portion in contact with the cavity space.

FIG. 2 is a partial cross-sectional view of a closed mold with a glass plate placed inside, similar to FIG. 1, and shows an example in which the elastic body having the above-mentioned sealing properties is used. 1st
The same parts as in the figure are indicated by the same numbers. The elastic bodies 13 and 14 having a sealing property are respectively provided only on the portions of the non-molding surfaces 7 and 8 of the glass plate 3 that are in contact with the cavity space 11, and have a width that allows the sealing property to be achieved. Both elastic bodies 13, 14 also have the role of holding the glass plate 3 within the mold. The non-molding surface of the glass plate that is not in contact with the elastic bodies 7 and 8 may be in contact with the mold, but it can also be made so that it does not come into contact with the mold as shown in FIG.

FIG. 3 is a partial sectional view similar to FIGS. 1 and 2 for explaining yet another embodiment of the present invention, and the same parts as in FIGS. 1 and 2 are designated by the same numbers. This feature resides in that an operating rod 15 that can be driven by external hydraulic pressure or the like presses down the elastic body 14 having sealing properties, thereby making the seal more complete and, in some cases, also positioning the glass plate 3. Operating rod 1
5 or the length direction of the elastic body (direction perpendicular to the paper surface)
It may also be a plate extending to . Further, the actuating rod may be provided in a portion of the elastic body 14 having other sealing properties, or may be provided in both elastic body portions. In addition, when the purpose is only to position the glass plate 3, a similar actuating rod can be used for the elastic body 13 of the glass plate 3,
14 may also be provided to contact a non-contacting, non-molding surface.

The molding needs to cover at least the end face 6 of the glass plate. However, if the molding and the glass plate are bonded only to the end surface 6 of the glass plate, the bonding strength between the two tends to be insufficient, so preferably at least one of the upper peripheral surface 4 and the lower peripheral surface 5 of the glass sheet,
More preferably, both are bonded. Therefore, the cross-sectional shape of the molding is the cavity space 11 shown in the figure.
It is preferable that the cross-sectional shape is U-shaped. The widths a and b of the upper peripheral surface 4 and the lower peripheral surface 5 may be different lengths or may be the same length. Also,
Although the lengths of a and b are not particularly limited,
Preferably, both are at least 1 mm.

As mentioned above, the molding can be formed not only on the entire peripheral part of the glass sheet, but also in a part of the peripheral part. For example, if we take a rectangular glass plate as an example, moldings can be formed not only on all four sides, but also on only one to three sides. Furthermore, it is also possible to form moldings only on the four corners or only on part of the sides of a rectangular sheet of glass. The cross-sectional shape of the molding is preferably U-shaped as described above, but
Based on this, we further created irregularities on the surface,
It is also possible to change the thickness and width of the three sides of the U-shape. As described below, in the reaction injection molding method,
Even if the length of the molding becomes longer (that is, the length of the cavity space becomes longer), the polyurethane resin raw material can be sufficiently distributed throughout the cavity space by simply injecting the polyurethane resin raw material from one injection hole. Is possible. However, in some cases, when forming a molding around the entire circumference of a rectangular glass plate, it may be preferable to provide two or more injection holes, such as injection holes at the four corners. Fourth
The figure is a partial cross-sectional view of a glass plate on which a molding is formed, and the molding 16 is made of a synthetic resin formed by injecting a polyurethane resin raw material into the cavity space 11 of FIG. 1 or 2 and solidifying it. .

Various types of sheet glass can be used as sheet glass for vehicles or architecture. For example, it may be a simple flat glass, a processed glass sheet, or a reinforced glass sheet. Processed sheet glass includes, for example, bent sheet glass such as windshields, rear glass, and door glass for automobiles, and these may also be laminated glass with an interlayer film, and may be heat-treated or chemically treated. It may also be a tempered glass reinforced by. The glass sheet may be an architectural glass sheet. Examples include architectural flat glass, double-layer glass, and molded glass.
In the present invention, it is possible to form a molding that tightly adheres to the surface of sheet glass, such as sheet glass, which has an uneven surface.

The surface of the glass sheet may also be subjected to various treatments. For example, it may be plated with heat ray reflective glass or coated with ceramics. Alternatively, it may be a sheet glass that has undergone a suitable treatment to form the molding. For example, it is possible to use a glass plate coated with a primer on the periphery of the glass plate where the molding is formed (mold forming surface) in order to improve the adhesive strength with the molding. Conversely, a removable protective coating can be applied to the non-molded surface after molding is formed, or a removable film can be adhered to the surface. Similarly, a paint serving as a sealing elastic body may be applied to the portion of the non-molding surface that is in contact with the molding forming surface, or a sealing elastic body may be adhered thereto.

The material of the mold is not particularly limited, but may be a metal mold or a so-called resin mold made of epoxy resin, polyester resin, or the like. In the case of a relatively soft resin mold, there is less risk of damaging or breaking the glass plate when it is pressed, and as long as it has sealing properties, it is not necessary to use the elastic body with the above-mentioned sealing properties. However, in the case of a mold made of a hard material such as a metal mold, it is preferable to interpose an elastic body in the contact portion with the sheet glass. It is preferable that this elastic body is interposed not only in the part having sealing properties but also in other contact parts where there is a risk of damaging or destroying the glass sheet. The dimensional accuracy of the mold is preferably high so as not to apply strong force locally to the glass sheet, and it is also preferable that the dimensional accuracy of the glass sheet is similarly high.

Preferably, the mold is a temperature adjustable mold.
In particular, it is preferable to be able to adjust the temperature of at least the mold portion in contact with the cavity space. This is because it is often necessary to control the solidification of the solidifiable synthetic resin raw material injected into the cavity space. The degree of heating or cooling of the mold depends on the type of solidified synthetic resin raw material being poured.
It is usually preferable to be able to heat up to about 150°C. The surface of the mold that is in contact with the non-molded surface of sheet glass often does not require particular temperature control, but it is necessary to adjust the temperature to prevent the intrusion of synthetic resin raw materials that can solidify into this area. may be preferable.

The material of the elastic body having sealing properties is as follows:
Synthetic resins, synthetic resin elastomers, rubber, etc. are preferred, but are not limited to these.
It may be made of elastic material such as soft synthetic resin or foamed synthetic resin. It is preferable that these materials have at least more elasticity than the material of the mold. It is preferable that the parts of the elastic body with sealing properties that may come into contact with the solidified synthetic resin raw material be made of a material with a non-adhesive surface, but even if this is not the case, preventive measures such as applying a mold release agent may be applied. A material with an adhesive surface may be used. As for the specific material,
For example, synthetic resins and synthetic rubbers with non-adhesive surfaces such as fluorocarbon resins, fluorocarbon rubbers, silicone resins, and silicone rubber, soft or semi-rigid polyurethane foams and other foamed synthetic resins, and hollow bodies of relatively soft synthetic resins. , composite materials such as resin-impregnated paper, etc. are preferred. In addition, relatively soft synthetic resins such as polyethylene, elastomers and rubbers other than those mentioned above may also be used. Further, as the elastic body for protecting the non-molded surface of the sheet glass, it is not particularly necessary to have a sealing property, but it is possible to use an elastic body having the above-mentioned sealing property, as well as other synthetic resins, elastomers, etc. , rubber, paint, film or sheet of paper, and various other materials can be used.

In the present invention, reaction injection molding (Reaction injection molding)
The Injection Molding method is a method in which a multi-component fluid synthetic resin raw material is mixed under pressure, the mixture is injected into a mold, and the synthetic resin raw material mixture is rapidly reacted in the mold to form a synthetic resin. A method for obtaining molded synthetic resin. This method is also called the "RIM method." The synthetic resin raw material is usually a liquid, and may be in the form of a slurry of liquid containing solids such as fillers. The method of reaction injection molding using synthetic resin raw materials mixed with reinforcing materials is sometimes called the "R-RIM method", but below:
This is considered to be one type of reaction injection molding method.

In the reaction injection molding method, the synthetic resin raw material is 2
It consists of a combination of the above ingredients. These components are in a combination that rapidly reacts to form a synthetic resin when mixed, and the components forming the polyurethane resin are a combination of a compound having an active hydrogen-containing group such as a polyol and a polyisocyanate compound. In particular, a polyol component whose main components are a highly reactive high molecular weight polyol and a chain extender (or crosslinking agent), and an isocyanate component whose main component is a polyisocyanate compound are used. Highly reactive high molecular weight polyols include, for example, polyether polyols with a high proportion of primary hydroxyl groups, and chain extenders (or crosslinking agents) include low molecular weight polyols such as ethylene glycol and 1,4-butanediol. and low molecular weight polyamines. The components containing these polyurethane resin raw materials can be used as fillers, reinforcing agents, colorants, blowing agents, catalysts, stabilizers, and other various additives.

In reaction injection molding, the two or more components are mixed at relatively high pressure and immediately injected into the cavity space. For example, a method is employed in which two components are ejected at high pressure from facing nozzles to mix them by collision, and the mixture is immediately injected into the cavity space at that pressure. Although the injection pressure in the reaction injection molding method is high, it is usually about 3 kg/cm ² or less, which is much lower than the injection pressure normally employed in the injection molding method for molten synthetic resin. The mold may be heated or at room temperature. In particular, it is preferable that the mold portion in contact with the cavity space be heated to room temperature to 100°C.
In addition, when molding polyurethane resin, especially
Preferably, it is heated to 40 to 70°C. The mixture of polyurethane resin raw materials filled in the cavity space is solidified by increasing its molecular weight through these reactions, and becomes a polyurethane resin. In this way, the reaction injection molding method uses a low-viscosity polyurethane resin raw material, mixes it at relatively low pressure and high speed, and injects it into the cavity space in the mold to fill it. The mixture filled in the mold rapidly reacts and solidifies to form a molded polyurethane resin. For an overview of the reaction injection molding method, see, for example, the magazine "Plastics", Vol. 28, No. 4 (1977), pages 27 to 31, published by Kogyo Chosenkai Co., Ltd., and Vol. 29 of the same magazine. No. 9 (1978), pages 13 to 24.

On the other hand, as a method for forming a molding around the periphery of a glass plate, molten synthetic resin, molten rubber, or other molten synthetic resin material is injected into the cavity space of a closed mold by placing the glass plate using a normal injection molding method. There is a method in which molding is formed around the glass plate by cooling and solidifying it. However, this method has various limitations during injection filling and cooling solidification due to the cavity space having a small cross-sectional area, long and curved shape, and also because the mold contains plate glass, which is easily broken. There are restrictions based on the existence of materials. For example, due to the shape of the cavity space and the high viscosity material being injected, it is likely to be difficult to sufficiently fill every corner of the cavity space with the material. To solve this problem, the injection pressure needs to be extremely high, and the temperature of the material needs to be raised to lower the viscosity. Furthermore, it is necessary to raise the mold temperature so that the injected material does not cool and solidify midway through the cavity space. For this reason, injection filling takes time and cooling and solidification of the material after filling also takes time, resulting in a longer molding time. Furthermore, since the injection pressure is high, the internal pressure in the cavity space increases, making it difficult to seal the portion where the mold and the glass plate contact each other, and material tends to leak from the sealed portion. On the other hand, in order to withstand the internal pressure of the cavity space, it is necessary to increase the mold clamping pressure. This increases the contact pressure between the mold and the glass sheet, increasing the risk of breaking the glass sheet. Further, since the temperature of the injected material and the mold is high, the glass sheet receives a large thermal shock, which increases the possibility that the glass sheet will break due to this thermal shock.

In the present invention, there is little possibility that the above problem will occur. Because the viscosity of the injected material is low, the material can be injected at high speed and with relatively low injection pressure, and because there are fewer restrictions due to the shape of the cavity space, it is easy to fill every corner of the space with the material. This is because. Also, due to the rapid injection filling and reaction solidification of the material, the molding time is extremely short. In addition, there is little mechanical and thermal shock to the glass sheet, and there is little risk of breaking the glass sheet.

In addition, in the present invention, as mentioned above, the term "mall" is used to include the gasket.
It cannot be said that the method of the present invention is particularly suitable for forming moldings. The distinction between moldings and gaskets used in the industry is generally not clear. In the present invention, gaskets are used for the purpose of sealing, and are made of elastic polyurethane resin such as elastomer or thermoplastic rubber. Molding refers to items used for decorative purposes, and refers to items made of elastomer and thermoplastic rubber, as well as other thermoplastic resins, thermoplastic and thermosetting polyurethane resins, and those with low elasticity. It's okay to be hot.

[Brief explanation of drawings]

FIG. 1 is a partial cross-sectional view of a mold in which sheet glass is arranged, showing one example of the method of the present invention, and FIG. 2 is a similar partial cross-sectional view showing another example. FIG. 3 is a partial cross-sectional view of a glass plate on which a molding is formed. FIG. 4 is a partial cross-sectional view of a glass plate on which a molding is formed. 1... Upper mold, 2... Lower mold, 3... Sheet glass, 9, 10...
Mold inner surface, 11... Cavity space, 13, 14...
Sealing elastic body, 14...Mall.

Claims (1)

[Claims] 1. In a method of forming a molding or gasket made of polyurethane resin around the periphery of a glass sheet for vehicles or architecture, the glass sheet is placed in a mold whose inner surface is coated with a release agent, the mold is closed, and the periphery of the glass sheet is formed. A cavity space for forming a molding or gasket is formed by the surface and the inner surface of the mold coated with a mold release agent, and then a polyurethane resin raw material is injected into the cavity space using a reaction injection molding method and solidified to solidify the polyurethane resin. A method for forming a molding or gasket made of polyurethane resin around the periphery of a sheet glass for vehicles or architecture, which comprises the steps of: thereafter removing the sheet glass from the mold.