JPS62155123A - Bonding dam formation method for window glass - Google Patents

Abstract

PURPOSE:To eliminate manual work including the removal of mold releasing paper, the pasting of a dam and the cut of a dam corner, and enable the application of automated work with a robot by forming the dam simply through the extrusion of a dam formation material of liquidity quality toward a dam formation position. CONSTITUTION:An adhesive is applied to a dam formation position on the surface of either window glass 10 or the fitting part thereof. A dam formation material having liquidity at normal temperature before curing, such as silicon rubber and polyurethane resin, or a hot melt type material having liquidity after heating is fed from a bulk melter 1 to a nozzle 3 via a heat pipe 4 and extruded to the surface of the window glass 10 in a string form with said nozzle 3 moved on a robot 2, thereby forming a dam 20. Then, the extruded material is cooled or subjected to bridge reaction for forming an elastic rubber and bonding monolithically with the upper surface of the dam formation position. Therefore, it is unnecessary to use an adhesive tape and manual work such as dam pasting and dam corner cutting is eliminated, thereby enabling the application of automated work.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of forming an adhesive dam used in an adhesive attachment method when attaching an automobile windshield or the like.

[Prior Art] Conventionally, dams have been extruded into a long length using an elastic material such as EPDM, and supplied with a double-sided adhesive tape containing non-woven fabric covered with release paper attached to the bottom surface. . As shown in FIG. 2, this dam 100 is manually attached to the window glass 100 with the adhesive force of the double-sided adhesive tape 101.
affixed in place along the periphery of the Note that the window glass 102 to which this dam 100 is attached is generally coated with a urethane sealer 10 as shown in FIG.
The dam 100 blocks the sealer 103 and seals the glass 1 of the sealer 103.
02 plays a role in preventing leaching to the surface.

[Problems to be solved by the invention] Conventional dams rely on manual labor to attach them;
Positioning was difficult and required a lot of man-hours. In addition, the dam is bent and pasted at a part of the window glass corner, but the elastic force of the rubber may overcome the adhesive force of the adhesive tape at that part, and the dam may lift up. In order to prevent this problem, workers make cuts in the dam with a knife or the like at some corners to weaken the elasticity of the dam and attach it.
There was a problem in that it required a large amount of man-hours.

The present invention has been made in view of these problems,
The present invention provides a method for forming a dam on a windshield that can be automated and can be automated.

[Means for Solving the Problems] The method for forming a dam on a windshield of the present invention includes forming a dam-forming material having flowability into a shaft at a dam-forming position on the surface of either the windshield or the part to which the windshield is attached. An extrusion process in which a string-like extruded body with a constant cross-sectional shape is formed by extrusion in a direction, and the extruded body is cooled or cross-linked to form a rubber elastic body, and the dam is formed (17) and fixed to be integrally bonded to the surface. It is characterized by consisting of a process.

The dam-forming material used is one that has good fluidity and exhibits rubber elasticity when formed into a dam. For example, silicone rubber
A material such as a polyurethane resin that has fluidity before curing and exhibits rubber elasticity after crosslinking and curing can be used. Alternatively, a bot-melt type material that exhibits rubber elasticity at room temperature and becomes fluid when heated can also be used. Note that fluidity is required only during the extrusion process described below.
It is desirable to lose fluidity quickly after extrusion.

In this sense, it is preferable to use a hot-melt type material that quickly loses fluidity upon cooling, rather than a material that involves a crosslinking reaction that takes time to harden. The hot-melt type dam-forming materials include thermoplastic excimers made of block copolymers of hard blocks and soft blocks such as SBR, thermoplastic urethanes, or viscous polymers with 10 to 60 parts. , softener is 10
~50 parts by weight, and 10 to 60 parts by weight of the tackifier,
It is possible to use a composition in which the elastic particles have 0 to 65 densities. Here, the polymer viscous material is S
One or a mixture of two or more of synthetic rubbers such as BR, butyl rubber, nitrile rubber, and chloroprene rubber, natural rubber, and resins such as diene block polymers can be used.

It is desirable that this polymeric viscous material is blended in an amount of 10 to 60 parts by weight; if it is less than 1 part by weight, the strength will be insufficient, and if it exceeds 60 parts by weight, the fluidity during heating will decrease and the extrusion workability will deteriorate. This is not desirable from a cost standpoint.

The softener imparts flexibility and tackiness to the viscous polymer, and well-known softeners such as vegetable oil, fatty oil, petroleum, coal tar, and synthetic resin can be used. . The composition of the softener particularly affects workability, and is most preferably in the range of 10 to 50 parts. The tackifier is one that imparts tackiness to the viscous polymer, and well-known agents such as xylene resin, phenol resin, coumaron resin, hydrogenated rosin ester, berbene resin, polyisobutylene, and polymer wax can be used. It is particularly desirable that this tackifier has a softening point of 80 to 130°C.

If the softening point is lower than 80°C, the heat resistance will be poor, and if it is higher than 130'C, the adhesion will be undesirably low. It is most desirable to use the above-mentioned softeners and tackifiers in amounts within the above-mentioned range; if the amount is less than the above-mentioned range, the adhesion will be poor, and if it is more than the above-mentioned range, the heat resistance and strength will be deteriorated. and molding workability deteriorates. Furthermore, it is also desirable to mix elastic particles. The elastic particles are preferably vulcanized powder rubber. For example, natural rubber, SB
Vulcanized powder rubbers such as R, nitrile rubber, and butyl rubber can be used alone or in combination of two or more.

The extrusion step is a step of extruding the above-described dam-forming material in the axial direction to form a string-like extruded body at the dam-forming position.

Here, the dam is generally formed on the peripheral surface of the windshield, but in some cases it may be formed on a part of the vehicle body or the like to which the windshield is attached. If the dam-forming material undergoes a crosslinking reaction, it is extruded to form an extruded body before the reaction and curing. If it is a hot melt type, it is formed by heating it until it becomes fluid and then extruding it.

In this extrusion process, the dam-forming material filled in a cartridge or the like may be manually extruded, but the dam-forming material is supplied by a supply device such as a pump, and the supplied dam-forming material (4
It is desirable to continuously discharge the material from a nozzle having a predetermined opening.

This makes it possible to carry out the extrusion process continuously, resulting in good efficiency. By changing the shape of the nozzle opening, the cross-sectional shape of the dam can be freely changed.

Although a worker can manually extrude using this nozzle, it is preferable to use a robot or the like. This saves manpower and improves the positioning accuracy of the extruded body.

The fixing step is a step of fixing the extruded body at the dam forming position. That is, if the dam undergoes a crosslinking reaction, it is left in that state until it undergoes reaction and hardening. Alternatively, means for accelerating the reaction such as heating can also be employed. Also, if the dam forming material is a hot melt type, simply cold fJ]
Just do it J: Yes.

The hot melt type is generally at a high temperature during extrusion, and is rapidly cooled from the surface by being discharged to the dam forming position at room temperature, so it has better shape retention than those that undergo a crosslinking reaction. Then, the extruded body undergoes a crosslinking reaction,
Alternatively, since the dam formed by cooling is integrally bonded to the surface where the dam is formed, a conventional adhesive tape is not required.

[Operations and Effects of the Invention] In the dam forming method of the present invention, a dam is formed simply by extruding a dam forming material to a dam forming position. Therefore, the labor of peeling off the release paper, pasting the dam, and cutting a part of the corner of the dam can be omitted. In addition, automation can be achieved using robots, which saves manpower and greatly improves positioning accuracy.

In addition, since the extruded body has fluidity immediately after extrusion, even if there are irregularities at the dam forming position, the extruded body can reliably follow the surface. Therefore, adhesive strength is improved and leaching of urethane sealers is reliably prevented. Furthermore, the shape of the dam can be conveniently adjusted by changing the extrusion speed of the dam-forming material, the shape of the nozzle, the moving speed of the nozzle, etc.

[Example] This will be explained in detail below based on examples.

(1) Production of dam-forming material As a viscous polymer, 15 parts by weight of butyl rubber (Butyl 268, manufactured by Nippon Butyl Co., Ltd.) and ethylene-vinyl acetate co-compound (EVA1830, manufactured by Nippon Unicar Co., Ltd. > 1 rota) were added.
Powdered rubber (average particle size 0.5ml) consisting of 25 parts of polybutene (HV-300, manufactured by Nippon Petrochemicals) as a softening agent, and a vulcanized body of natural rubber as elastic particles.
40 parts by weight were put into a pressure kneader and heated to 100℃~12
The mixture was stirred at 0°C for 20-30 minutes. Furthermore, as a tackifying agent, Kumaronju IFf (NT-2,8 manufactured by Tetsu Kagaku Co., Ltd.) 15!
Add 1 or 2 days worth into the above composition and wait for 10 minutes! $1
By doing so, a uniform dam-forming material was obtained. The various physical properties of this dam-forming material at room temperature are shown in the table in comparison with conventionally used EPDM rubber.

As shown in this table, this dam-forming material possesses the physical properties necessary for an adhesive dam.

(2) Construction Using the dam-forming material produced in (1), a dam was formed on the surface of the peripheral edge of the window glass using the apparatus shown in FIG.

This equipment is a bulk melter (manufactured by Nordson, Model 5).
00) 1, a robot 2, a nozzle 3 held on the working arm of the robot 2, and a heat vibrator 4 that conveys melted dam-forming material from the bulk melter 1 to the nozzle 3. First, the dam-forming material in the container 5 is heated to 140°C on the platen (heating plate) of the bulk melter 1.
melted. The molten dam-forming material is pumped by a built-in pump at a pressure of 70 kg/m1I12, and is discharged from the nozzle 3 onto the surface of the window glass 10 through the pipes 1 to 4 heated to 140°C.

The opening of the nozzle 3 has a square shape with a side of 8 m + m, and 1
00~500o/min i12! It is configured so that the discharge amount can be freely controlled by the surroundings. Furthermore, the robot 2 moves the nozzle 3 along the surface while discharging the dam-forming material at a predetermined position on the surface of the window glass 10, and teaches the robot 2 to reliably form a string-like extruded body at the dam-forming position. has been done.

The extruded body extruded to the dam forming position by the robot 3 was cooled and solidified to become the dam 20.

(3) Evaluate the adhesion of the test example 1g to the wind glass of the dam (
The shear adhesion was measured in order to determine the results. For comparison, we simultaneously measured the shear adhesive strength of a dam preformed from conventionally used EPDM rubber (manufactured by Toyoda Gosei Co., Ltd.) and adhered to a window glass with adhesive tape (manufactured by Nitto Denko Corporation, M2O3). . The results were 10 kg/cwt for the dam of this example, and 5 kg/cwt for the conventional dam made of EPDM rubber. ＞It has approximately twice the adhesive strength of conventional products.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing an example of an apparatus used in the dam forming method of the present invention. FIG. 2 shows a conventional dam forming method, and is a sectional view showing a state in which a dam is adhered to a window glass with an adhesive tape. FIG. 3 is a cross-sectional view showing the state in which the glass with the dam is adhered to the vehicle body. 1... Bulk melter 2... Robot 3... Nozzle 4... Heat pipe 5... Container 10.102... Wind glass 20.100... Dam 101... Adhesive 103
...Urethane sealer 104...Car body patent applicant Toyota Motor Corporation representative
Patent attorney Hirodo Okawa Patent attorney Akio Maruyama Figure 2

Claims (3)

[Claims] (1) An extrusion step of extruding a fluid dam-forming material in the axial direction at a dam-forming position on the surface of either the window glass or the part to which the window glass is attached to form a string-like extruded body with a constant cross-sectional shape; A method for forming an adhesive dam for window glass, comprising: a fixing step of cooling or crosslinking the extruded body to form a rubber elastic body and integrally bonding the extruded body to the surface of the dam formation position. (2) The method for forming an adhesive dam on a window glass according to claim 1, wherein the extrusion step is performed by continuously discharging the dam forming material supplied from a supply device from a nozzle having an opening in a predetermined shape. (3) The dam forming material contains 10 to 60 parts by weight of a viscous polymer, 10 to 50 parts by weight of a softener, and 10 to 10 parts by weight of a tackifier.
60 parts by weight of the elastic particles and 0 to 65 parts by weight of the elastic particles, and the extrusion step is carried out by heating and melting the dam-forming material.