JPH0586966B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a molding made of vinyl chloride resin that is attached to the peripheral edge of a window glass mounted on an automobile so as to come into contact with the window glass.
The present invention relates to a molding that can reduce the occurrence of scraping and squeak sounds without post-processing such as applying lubricant. (Prior Art) Vinyl chloride resins are used in large quantities as molding materials for vehicles because of their excellent texture, good moldability, weather resistance, and the like. However, when automotive moldings are molded using vinyl chloride resin, especially soft vinyl chloride resin that has been made flexible by adding plasticizers, the frictional force on the surface of the molded product becomes large, especially around the periphery of the window glass. The molding that is attached to the window is subject to vibrations during driving, which tends to cause rubbing and squeak sounds between the molding and the window glass. This scraping and squeak noise is thought to be caused by the stick slip phenomenon.To reduce these sounds, reduce the absolute values of the static friction coefficient and kinetic friction coefficient between the two surfaces in contact. At the same time, it is said that it is effective to reduce the difference between the two friction coefficients. In order to prevent such noise, conventional methods have been to implant hair or apply a lubricant to the parts that rub against each other, or to add a large amount of lubricant such as fatty acid amide, silicone oil, liquid paraffin, paraffin wax, etc. to the resin composition. A method of adding has also been proposed. (Problems to be Solved by the Invention) However, conventional methods of flocking and applying lubricant as means for reducing scraping and squeaking noises are unsuitable for complex shapes and result in an increase in the number of steps. In addition, adding a large amount of lubricant or the like to the resin composition can significantly inhibit the adhesion of the molded product, make the surface of the molded product sticky, and cause dirt to easily adhere to it.
There are problems such as whitening and discoloration, and although some effects have been recognized as countermeasures against scraping and squeak noises, it cannot be said to be sufficient. (Means for Solving the Problems) The present inventor has solved the conventional problems and has developed a vinyl chloride-based Providing a certain level of roughness to the surface of the resin molding and adding an appropriate amount of paraffin wax, which is solid at room temperature, minimizes problems such as inhibiting the adhesion of the molding and discoloring the surface. The present inventors have discovered that the generation of abnormal noises such as scraping sounds and squeaks can be dramatically reduced, and have achieved the present invention. The present invention will be explained in detail below. The vinyl chloride resin used in the present invention is a copolymer of polyhydric alcohol, diacrylic ester, and vinyl chloride monomer, and has a tetrahydrofuran insoluble content of 1 to 30% by weight and a soluble content of 99 to 70% by weight. Consists of %.
Polymerization degree of tetrahydrofuran soluble content is 700~
3000 is generally preferred. Examples of diacrylic esters of polyhydric alcohols include diethylene glycol diacrylate, polyethylene glycol diacrylate, and 1,3-butylene glycol diacrylate, but the method for producing the tetrahydrofuran-insoluble fraction is not particularly limited. This tetrahydrofuran-insoluble content influences the surface roughness of the molded product. Furthermore, the paraffin wax used in the present invention is
It is preferably solid at room temperature, and should be added in an amount of 0.1 parts by weight or more and less than 3 parts by weight per 100 parts by weight of the vinyl chloride resin. In addition, its melting point is 45~
A temperature of 70℃ is preferable to prevent rubbing and squeak noises. If the amount added is less than 0.1 part by weight, the effect of adding wax will not appear, and the reduction of abnormal noises such as rubbing sounds and squeaks will not be apparent. If the amount is 3 parts by weight or more, the adhesive force of the molded product will decrease and the surface will become white over a long period of time, which is not preferable. Furthermore, in addition to the above, plasticizers, stabilizers, additives, fillers, etc. which are usually added to the vinyl chloride resin composition may be added. For example, as for the plasticizer, any conventionally used plasticizer may be used, and the amount added is preferably in the range of 20 to 150 parts by weight per 100 parts by weight of the resin, but there is no particular restriction. Further, the filler plays an auxiliary role in adjusting the surface roughness, and is preferably used from the viewpoint of reducing product costs, and is generally preferably added in an amount of 100 parts by weight or less per 100 parts by weight of the resin. There are no particular restrictions on the type of filler, and examples include calcium carbonate, clay, and talc, with calcium carbonate being preferred. In the present invention, the surface roughness of the molded product formed by molding the composition is important, and it is necessary to have a surface roughness of 1 μ or more. However, the surface roughness is 20μ
If this is the case, the surface smoothness may sometimes be lost in terms of appearance, so in the case of molded products where appearance and quality are a concern, it is preferable to have a surface roughness of 1 to 20 μm. In addition, when the surface roughness is less than 1μ, the coefficient of static friction becomes particularly large, causing scraping noise and
This is not preferable because it does not have the effect of preventing squeak noise. In order to obtain the above-mentioned molded product, each component is uniformly mixed and kneaded using a ribbon blender, mixing roll, etc., and usually pelletized using a pelletizer to obtain a raw material. The molding of the present invention is manufactured using this raw material and a method such as extrusion molding or injection molding, but the molding method may be any conventionally used method such as extrusion molding or injection molding. There are no restrictions. (Function) In the molding of the present invention, only when a specified amount of paraffin wax is added to the vinyl chloride resin and the surface roughness of the molded product is 1μ or more, the synergistic effect improves the adhesion and whiteness of the surface. It is effective as a member for preventing abnormal noises such as rubbing noises with window glass, squeaks, etc., without problems such as corrosion. For example, the paraffin wax used in the present invention, or a composition in which silicone oil, liquid paraffin, etc., which are conventionally said to be effective in countermeasures against rubbing sounds, squeaks, etc., are added to vinyl chloride resin. For molded products with a mirror-like surface roughness, or for molded products molded with a surface roughness of 1μ or more using a vinyl chloride resin composition that does not contain paraffin wax, some effect is observed, but it is not sufficient. I can't say that. Furthermore, in molded products made by adding lubricants such as silicone oil and liquid paraffin other than paraffin wax to vinyl chloride resins, molded products with a surface roughness of 1μ or more are less likely to rub than those without the addition of lubricants. The generation of noise and squeaks is the same or even worse. (Examples) The present invention will now be described with reference to Examples and Comparative Examples. Examples 1 to 7, Comparative Examples 1 to 9 A phthalate ester as a plasticizer and a phthalate ester as a stabilizer were added to a vinyl chloride resin, which is a copolymer of a diacrylic ester of a polyhydric alcohol and a vinyl chloride monomer. Epoxidized soybean oil, lead-based stabilizer, calcium carbonate as a filler, paraffin wax, lubricant such as silicone oil, etc. are blended and kneaded as shown in Table 1, and the resulting mixtures are extruded using an extruder. Molded into vehicle window frame material (window molding), Examples 1 to 7, Comparative Examples 1 to 9
A molded product was obtained. The measured values of the surface roughness of the window molding molded products of each example and comparative example were
Shown in the table.

【table】

[Table] Next, the window molding molded products of Examples 1 to 7 and Comparative Examples 1 to 9 were actually adhered and assembled to a vehicle, and the vehicle was artificially deformed so that a torsional force was applied. From window molding
Table 2 shows the noise levels measured with a sound level meter (A range) at a distance of 10 cm. The background noise level during this experiment was 51 to 53 dB, and the sound level evaluation in Table 2 is: ◎: 55 dB or less (no sound) ○: 55 to 58 dB (very low sound, difficult to hear) × : 58 to 65 dB (produces sound) ××: 65 dB or more (produces very loud sound). Table 2 also lists the surface appearance and adhesive strength of the molded products attached to the vehicle, both at the initial stage and after the heating acceleration experiment.
Adhesive strength is determined by measuring the force when separating the window molding from the vehicle.
This is the result after the surface of the molded product was heated and kept warm for 5 hours using an infrared lamp at 80°C. The adhesive strength evaluation in Table 2 is: ◎: 50Kg or more (strong enough) ○: 40-50Kg (sufficient for practical strength) △: 30-40Kg (insufficient for practical strength) ×: 30Kg or less ( (very weak and easily removed).

[Table] (Effects of the invention) The vinyl chloride resin molding of the present invention is a molded product that uses a composition in which a specified amount of paraffin wax is added to a vinyl chloride resin and has a surface roughness of 1μ or more. This minimizes adhesion inhibition, surface discoloration, stickiness, etc., and reduces rubbing noise and
The effect of preventing abnormal noises such as squeaks was obtained.

Claims (1)

[Claims] 1 A molding made of vinyl chloride resin that is attached to the peripheral edge of a window glass placed on a car so as to be in contact with the window glass, the molding having a diameter of 1 to 30
Tetrahydrofuran insoluble and soluble content 99% by weight
At least 0.1 part by weight of paraffin wax per 100 parts by weight of vinyl chloride resin consisting of ~70% by weight3
1. A molding for an automobile, comprising a vinyl chloride resin composition containing less than one part by weight, and the surface of the molded product having a roughness of 1 μm or more.