JPH0148164B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a weather strip attached to a door window frame of an automobile. Conventionally, weather strips have been used for this type of window frame that holds the window glass in a slidable manner.
For example, there is one shown in FIG. In the figure, reference numeral 1 denotes the main body of the weather strip, which is integrally formed by extrusion molding of synthetic resin or rubber, and includes a base 1a that is fitted into the bottom of the sash 2, and a base 1a that is bent at both ends of the base 1a. It consists of a pair of side wall portions 1b that are erected and fitted to both side walls of the sash 2, and a lip portion 1c that extends in a curved manner from the end of the side wall portion 1b so as to be folded back toward the base portion 1a. 3 is a window glass. In addition, near the surface of the base portion 1a and the lip portion 1c where the window glass 3 makes sliding contact,
Flocking 4 is performed using an electrostatic flocking method or the like. In such a weather strip structure, the flocking 4 reduces the contact resistance to the window glass 3 and obtains an appropriate glass holding force, thereby allowing the window glass 3 to slide smoothly. There is. However, this configuration has the drawback that the process of applying flocking 4 to the soft weatherstrip main body 1 is complicated, and a special adhesive and pile are used, resulting in an unavoidable increase in cost. In addition, there were problems in practical use, such as the fact that the flocked hair 4 was easily peeled off and had a short lifespan. On the other hand, in order to improve this drawback, a weather strip has also been provided in which a plurality of protrusions 5 are integrally provided on the surface of the main body 1 of the weather strip that comes into sliding contact with the window glass 3, as shown in FIG. There is. However, although it is advantageous in terms of simple structure and low cost, the sliding resistance is relatively large. In addition, weather strips made of urethane resin with silicone oil added or coated with nylon are also available, but urethane resin with silicone oil has the effects of silicone oil (improved water repellency and smoothness). If the amount added is increased to , the adhesion to the substrate will deteriorate,
At the same time, it becomes easy to peel off, and at the same time, curing conditions,
This will have an adverse effect during post-processing (adhesion processing). Furthermore, the nylon coating has a problem of increased sliding resistance when wet due to its hygroscopic properties. In order to solve this problem, we can directly mix and apply silicone oil to the nylon coat.
Alternatively, it has been proposed to apply these two layers separately, but each method has drawbacks in terms of adhesion, increased man-hours, and abrasion resistance. The present invention has been made in order to eliminate the above-mentioned drawbacks of the prior art, and includes (A) By applying a coating composition containing urethane-based or methanol-soluble nylon-based paint and (B) spherical resin microcapsules containing an oily substance as essential components, weather protection can be achieved in a single application operation. An object of the present invention is to provide a weather strip for automobiles that forms a coating film that has good adhesion to the strip base material and has excellent abrasion resistance, thereby reducing sliding resistance against the windshield. . That is, by applying the coating composition to the surface of the weather strip that comes into sliding contact with the sliding glass and drying it, the sliding surface is made microscopically uneven;
By reducing the contact area with the window glass, the sliding resistance is reduced, and at the same time, as the number of sliding increases, the microcapsules are sequentially destroyed and the oily substance contained therein gradually oozes out. This has the effect of improving sliding properties, durable abrasion resistance, watertightness, etc. In addition, when this paint is applied and dried, oily substances are inside the capsule, so
Adhesiveness to the base material is not impaired, and post-processing (adhesion processing) is not adversely affected.
In addition, it is economically extremely advantageous because it requires only one application, requires less man-hours, and simplifies the process. The paint (A) used in the present invention is used as a binder for the microcapsules (B) to form a film on the weather strip. By selecting a paint, the weatherstrip can have excellent properties such as adhesion to the base material, film strength, flexibility, and weather resistance. Conventionally known surface coating paints can be used as such paints, and the solvents used include, for example, in the case of urethane-based paints, methyl ethyl ketone, toluene, ethyl acetate, trichloroethylene, trichloroethane,
Solvents with an SP value of around 9 such as acetone, and in the case of methanol-soluble nylon, hydrocarbon solvents such as methanol, ethanol, isopropanol, and n-hexane are preferably used. The method for preparing the microcapsules (B) used in the present invention is as follows: A solution containing a mixture of an oily substance, a polymerizable monomer for shell formation (e.g., acrylic monomer, vinylidene chloride, etc.), a dispersant, and a catalyst is dissolved in an aqueous solution. Those using the in-sight polymerization method (particle size is preferably 1 to 100μ), those using interfacial polycondensation like nylon (preferably particle size 1 to 50μ), and emulsification of oily substances in gelatin solution. There are methods such as those using the coacervate method, which involves mixing and adding gum arabic to form a film. The material of these microcapsule shells is preferably one that does not dissolve in the solvent used in the paint in (A) above. For example, nylon shells are used for urethane paints; A combination of acrylic or polyvinylidene chloride is preferred. The oily substance used in the present invention can improve the watertightness and water repellency of the weather strip, and includes silicone oil, alkyl alkylate, and ester type (e.g., phthalate type).
Oil etc. can be used. For encapsulation, there are products with a viscosity of 10 cst to 10,000 cst, but higher viscosity is better for slipperiness, but durability is poorer.
Also, if the viscosity is high, the inclusion property is poor, so 1000~
It is preferably about 2000 cst. The amount of oily substance contained can be 10 to 90% by weight of the total weight of the microcapsule, but it is 50 to 90% by weight.
Preferably it is 80% by weight. If the amount of encapsulation is large, the capsule is likely to collapse, and the oily substance oozes out during initial sliding, producing an effect, but the effect cannot be sustained. Furthermore, if the amount of inclusion is small, the effect will be exerted after the wear has progressed, but the effect will not be realized during the initial sliding. Therefore, most preferably, the amount of inclusion is distributed, and the amount of inclusion is 50~
By using an appropriate mixture of different microcapsules of 80% by weight, an effect similar to that of a so-called Spansle capsule can be expected. Also,
For the same reason, durability can also be improved by providing a distribution in the particle size of the microcapsules. The amount of such microcapsules (B) used is 10100 parts by weight per 100 parts by weight of the paint (A) in terms of solid content.
Parts by weight are preferred. The coating composition used in the present invention has the above-mentioned (A) coating material and the above-mentioned (B) microcapsules as essential components, but also forms irregularities on the surface of the coating film to reduce the sliding resistance with the window glass. For this purpose, it is preferable to include nylon particles. These nylon particles are made of, for example, nylon dissolved in a solvent such as (C') phenol or cresol, and a solvent that has relatively low solubility in these solvents (poor solvents such as methanol,
There are colloidal nylon precipitated by mixing and stirring (isopropyl alcohol, etc.), and (C″) nylon powder with an average particle size of preferably 5 to 100μ.The amount of these nylon particles used is based on the solid content ratio. For 100 parts by weight of the paint in (A) above, in the case of (C'), 1
~30 parts by weight, preferably 10 to 100 parts by weight in the case of (C″). The paint of (A), the microcapsules of (B), and optionally the nylon of (C′) or (C″). The coating composition obtained by blending the particles in a predetermined amount is applied to the sliding surface of the main body 1 of the weather strip shown in FIG. 1 that comes into contact with the window glass, as shown in FIG. 3a. Subsequently, by drying and baking, the paint 11 of (A), microcapsules 12, and optionally nylon particles 1 are coated on the weatherstrip body 1.
3 is integrated to form a microscopically uneven surface 14 as shown in FIG. 3b. The main body 1 of the weather strip having this uneven surface 14 is shown in FIGS. 4 to 6.
The result will be as shown in the figure. 6 is a vehicle body panel. From the formation of the main body of the weather strip to the formation of the lubricating layer 14, as shown in FIG. A vulcanization process in which the coating composition is vulcanized using a device, a coating process in which the coating composition is applied to the main body of the molded weather strip using a coating roll, spraying, brushing, etc., and approximately 100% after drying.
It is formed through a heating and baking process at 120℃ for 5 minutes. As shown in Figure 7B, in the case of a weather strip made of thermoplastic synthetic resin,
An extrusion process in which vinyl chloride material is extruded into a predetermined shape using an extruder, a process in which the molded product is cooled and hardened using a cooling device, a process in which a primer is applied to the main body of the molded weather strip, and it is dried. It is formed through a coating process in which a coating composition is applied to the main body of a molded weather strip using a coating roll, and a process in which the coating is simultaneously dried, baked, and annealed at about 120° C. for 5 minutes. The primer application and drying steps described in the above steps may be omitted depending on the case. Examples and Comparative Examples As Examples and Comparative Examples, seven types of coating compositions (Examples 1 to 3,
Comparative Examples 1 to 4) were prepared, and the physical properties of each paint, including initial sliding resistance, abrasion resistance, and adhesion, were measured under the following test conditions. The results are shown in Table 2.

【table】

【table】

〔Test conditions〕

○B Initial sliding resistance is determined by extruding PVC glass run, applying a primer, drying each paint, and using a sliding test machine as shown in Figure 8 (16 is satoshi, 17 is glass run, 18 is glass). The resistance was measured. Glass: 160 x 200 x 3.5t Stroke: 250mm Speed: 3m/min Sample: 500mm ○B For the abrasion resistance test, the glass run coated with each paint was slid on the glass edge part using a constant load abrasion tester. Load: 3Kg Glass: 4.0mt x 120mm Sample: 50mm Stroke: 100mm Speed: 30 reciprocations/min○c For the adhesion test, after applying a urethane primer to a PVC test piece, each paint was applied with a brush. Gauze was placed on top of it, paint was applied, dried, and baked, and then a 180° peel test was performed on a 25 mm width and measured. Peeling speed: 200 mm/min As shown in the results in Table 2, from the viewpoint of sliding properties, abrasion resistance, and adhesion, the coating composition of the present invention was applied to the sliding surface, and the dried weather strip was was confirmed to have excellent effects.

[Brief explanation of drawings]

Figure 1 is a sectional view showing the mounting structure of a conventional weather strip, Figure 2 is a perspective view showing another conventional example of a weather strip, and Figures 3 a and b are surface treatments of the weather strip. FIGS. 4 to 6 are cross-sectional views showing the mounting structure of the weather strip of the present invention, and FIGS. 7 A and B are process diagrams showing the method for forming the weather strip, which also includes a paint application step. The process diagram shown in FIG. 8 is an explanatory diagram showing a method of measuring the initial sliding resistance of the coated uneven surface. DESCRIPTION OF SYMBOLS 1... Weather strip main body, 11... Paint, 12... Microcapsules, 13... Nylon particles, 14... Uneven surface.

Claims (1)

[Scope of Claims] 1. In an automotive weather strip made of rubber or thermoplastic resin, the surface that comes into sliding contact with the sliding glass is coated with (A) a urethane-based or methanol-soluble nylon-based paint, and ( B) A weather strip for automobiles, characterized in that it is coated with a coating composition containing as an essential component spherical resin microcapsules containing an oily substance.