JPS6146008B2 - - Google Patents

Description

[Detailed description of the invention]

This invention is mainly used for automobiles, and is used to prevent squeaks from occurring when the weather strip is in use with the door, and other problems such as close contact between the weather strips and other glass or painted surfaces, and between weather strips. The present invention relates to a weather strip that has excellent weather resistance and durability and has the ability to prevent binding due to freezing at low temperatures. Conventionally, weather strips for automobiles have been coated with urethane paint or silicone paint as necessary, mainly to reduce slip resistance. Also, the paint was coated with urethane paint to which silicone oil was added. However, weather strips treated with urethane paint do not have sufficient slippage, so when driving on rough roads, they may cause squeaks due to friction with the door, or they may stick to the glass or paint plate on the body. There were some shortcomings such as: Furthermore, weather strips treated with silicone paints have problems with binding and durability due to freezing at low temperatures. Furthermore, weather strips treated with urethane paints containing silicone oil have been known to have poor weather resistance and durability because the silicone oil is washed away by physical forces such as rainwater. Therefore, the inventors aimed to eliminate the drawbacks of the conventional methods, and searched for a means to eliminate these drawbacks while retaining the respective characteristics of both. In other words, a silicone polymer having a functional group that can react with isocyanate is selected, an isocyanate-terminated prepolymer made by reacting this with a polyisocyanate compound, and a surface treatment agent made by mixing urethane paint with this are used to create a weather-resistant surface treatment agent. It has been found that this material has extremely favorable performance when used as a strip. The silicone polymer having a functional group capable of reacting with isocyanate is, for example, one having two or more active hydrogens, such as alcohol-modified silicone or amine-modified silicone. In addition, as a polyisocyanate compound, for example, toluene diisocyanate (abbreviation:
TDI), diphenylmethane diisocyanate (abbreviated as MDI), etc. are often used. The composition ratio of the isocyanate-terminated prepolymer of the silicone polymer to the polyurethane paint may be 5 to 50% by weight. At the end of 5% by weight, the performance of preventing squeaks, adhesion, and freezing from clumping, which have been pointed out as the conventional drawbacks, cannot be sufficiently exhibited. On the other hand, if it exceeds 50% by weight, the solubility of the mixture will be poor and a desirable coating appearance will not be obtained. Next, embodiments of the present invention will be described with reference to Examples. Example 1 Silicone polymer L-9000 (manufactured by Nippon Unica)
The solid content ratio of NC0% = 5%, silicone prepolymer (abbreviation CPP), which is made by reacting MDI with polyurethane paint (abbreviation UCC), is
Five types of paints blended at 5, 10, 20, 30, and 50% by weight were diluted with toluene to bring the total solids concentration to 5%.
% was used as a surface treatment agent for weather strips. Add about 2 coats of weather strip to this surface treatment agent.
After dipping for a second, setting in a room temperature atmosphere for about 5 minutes, and then heating at 120° C. for 20 minutes to form a coating fixing film of the surface treatment agent. Example 2 A silicone play polymer (abbreviation: CPP) with NC0% = 5%, which is made by reacting silicone polymer SF8427 (Torray Silicone) with TDI, was used as a one-can polydure paint (manufactured by Mikuni Paint Co., Ltd.), which is a polyurethane paint (abbreviation: UCC). ), a paint blended at a solid content ratio of 10% by weight was used in Example-
A surface treatment agent obtained in the same manner as in Example 1 was applied to a weather strip as a coating fixing film. Example 3 Silicone prepolymer prepared in Example-2
A surface treatment agent obtained in the same manner as in Example 1 was applied to a paint in which CPP was blended at 10% by weight in terms of solid content with the polyurethane paint UCC Arunate paint (manufactured by Rock Paint Co., Ltd.). The coating was spray-painted using a nozzle and then heated in a 120°C atmosphere for 20 minutes to form a coating and fixing film. Example 4 A silicone prepolymer (abbreviation: CPP) with NC0% = 10%, which is made by reacting silicone polymer SF8427 (Toray Silicone) with TDI, was used as a one-can polydure paint (manufactured by Mikuni Paint Co., Ltd.), which is a polyurethane paint (abbreviation: UCC). , solid content ratio
A coating fixing film was formed on the surface of a weather strip using a 10% by weight blended paint and a surface treatment agent obtained in the same manner as in Example 1 and in the same manner as in Example 3. Comparative Example (a) A polyurethane paint UCC one-can polydure paint (manufactured by Mikuni Paint Co., Ltd.) was diluted with toluene to give a total solids concentration of 5% and was weatherstripped using the same treatment method as in Example-1. The surface of the plate is coated. Comparative example B: A paint in which silicone oil KF96H (abbreviation CO), (silicon oil 10000CS manufactured by Shin-Etsu Chemical Co., Ltd.) was blended at a solid content ratio of 5% by weight with the polyurethane paint UCC Arunate paint (manufactured by Roku Paint Co., Ltd.). , diluted with toluene to bring the total solids concentration to 5.
The surface of the weather strip was coated with the prepared liquid prepared in 100% by the same method as in Example-1. Comparative Example C Silicone prepolymer of Example-1 (abbreviation
The surface of the weather strip was coated with a 3% concentration preparation of CPP) in the same manner as in Example-1. Comparative Example d The surface of a weather strip was coated with a 55% concentration preparation of the silicone prepolymer of Example-1 in the same manner as in Example-1. Tables 1 and 2 show the results of physical property tests such as squeak noise, slip resistance, adhesion, abrasion resistance of the coating film, and freeze adhesion for each of the above composition examples.

[Table] In contrast to the above examples, the comparative examples in Table 2 are polyurethane paint UCC alone, polyurethane paint UCC
This is a blend of silicone oil CO and silicone prepolymer to form a covering fixing film for the silicone prepolymer alone.

[Table] The weather strips used in Tables 1 and 2 above have the cross-sectional shape shown in the perspective view in Figure 1, but there are many other shapes of weather strips. . In the figure, 2 is a weather strip, 2a
2b is a covering fixing film, and 2c is a hollow portion. The physical properties in Tables 1 and 2 above were determined using the following test method. Squeak noise test This is a comparison of the noise generated when driving on rough roads using an actual vehicle, where ○ indicates good quality and × indicates poor quality. Slip resistance test In Figure 2, 1 is the weather strip 2
The support 3 is a painted plate, which is a 1.0 mm thick steel plate coated with thermosetting acrylic enamel to a thickness of 45 μm. This painted board 3 has a length of 200
The sliding resistance (g) was measured when the coated plate was moved at a speed of 50 mm/min in the length direction of the weather strip, held between a 4 mm presser foot and a 4 mm weather strip. Adhesion test As shown in Figure 3, weather strip plate samples 4 and 5 (length 10 mm x width 50 mm x thickness 12 mm)
As shown in Fig. 3-A, the surfaces on which the surface treatment agent coated fixing film was formed were placed together with heavy water, and then
As shown in B, the adhesion force was measured after compressing by 50% in the direction of the arrow and holding it in an atmosphere at 70°C for 7 days. Abrasion resistance test As shown in Figure 4-A, the weather strip 2 is fixed and brought into contact with the painted plate 3, and as shown in Figure 4-B, the weather strip 2 is compressed by 2 mm, the amplitude is 3 mm, The weather strip 2 was rubbed against the painted plate in a direction perpendicular to the longitudinal direction at a vibration frequency of 1000 cpm, and the state of the coated fixing film was observed based on the vibration frequency. Regarding wear resistance, a comparative test was conducted before and after deterioration. Freezing power test As shown in Figure 5, weather strip 2
A piece of 2 cm long is crimped onto the painted surface 6a on which water droplets have been applied in advance, with a presser foot of 5 mm. In this state, leave it in an atmosphere of -15°C for 15 minutes to permanently bond between the weather strip 2 and the painted surface 6a, then move the painted plate 6 in the direction of the arrow and remove it from the permanently bonded surface. The binding strength due to freezing was measured. The binding strength was also compared after the deterioration test and before the deterioration test. Weather resistance deterioration test is conducted using Sun-shine Weather-o-meter.
It was aged for 300 hours using As shown in the physical properties of the composition examples of Examples in Table 1 and Comparative Examples in Table 2, which were conducted using the above test method, the silicone resin which is the surface treatment agent for the weather strip of the present invention The usable blending ratio of the polymer CPP to the urethane paint UCC is 5 to 50% by weight, but the most practically preferred range is about 10 to 30% by weight. In addition, the weather strip of the present invention having a fixed film coated with this surface treatment agent prevents squeaks caused by door rubbing and improves the slip resistance and adhesion of the urethane coating, and in particular, significantly improves it. The point is deterioration resistance, and in terms of abrasion resistance and freezing performance (i.e., binding strength due to freezing), both properties exhibit characteristics that hardly reduce the performance before deterioration.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the weather strip of the present invention, Fig. 2 is a schematic diagram showing the slip resistance test method, Fig. 3-A and B is a schematic diagram showing the adhesion test method, and Fig. 4 -A and B are schematic diagrams showing the abrasion resistance test method, and FIG. 5 is a schematic diagram showing the freezing power test method. CPP...Isocyanate-terminated prepolymer of silicone polymer, UCC...Polyurethane paint,
2 ...Weather strip, 2a...Coating fixing film (of surface treatment agent).

Claims (1)

[Claims] 1. A prepolymer having an isocyanate group at the end, which is obtained by reacting a silicone polymer having active groups such as a hydroxyl group or an amino group with a bifunctional isocyanate, is applied to a polyurethane paint for 5 to 50 minutes.
A weather strip with a coating fixing film containing 50% by weight of a surface treatment agent.