JPS6349001B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an asphalt coating material that is applied to floorboards of vehicles and the like for anti-vibration and waterproof treatment.

Generally, a coating material mainly composed of asphalt is applied to the floorboards of vehicles for vibration-proofing and waterproofing purposes.

Conventionally, from the viewpoint that the anti-vibration effect on the car body floor depends on the weight of the material coated on the flat surface, talc, asbestos powder, metal powder, and mica were used as inorganic fillers simply as fillers for the main component asphalt. It is usual to obtain a coating material with an increased amount by adding such materials and apply it to a thickness of approximately 2 mm. It is known that an inorganic filler is added to mica, but it is in the form of scales with an aspect ratio of about 30, and is understood as a variation of the inorganic filler as a mere weight increaser. It's just there. Therefore, the more the amount of inorganic filler such as mica is increased, the more the vibration damping properties can be improved. However, due to the desire to conserve resources and energy, it is disadvantageous to improve characteristics by increasing weight, and one of the challenges in vehicles, etc. is to reduce the weight as much as possible.
From this point of view, it is not preferable to try to improve the vibration damping characteristics.

The present invention focuses on the fact that mica is a mineral that exfoliates in layers, and is dispersed and oriented in layers when mixed into asphalt and rolled. The object of the present invention is to provide an asphalt coating material that can improve vibration characteristics.

That is, in the coating agent according to the present invention, mica having a large aspect ratio is dispersed and oriented in a layer in asphalt, and by mixing mica with an aspect ratio of 90 or more as a critical point, approximately It has been found that the same or better vibration damping effect can be achieved.

This will be explained below based on the illustrated embodiments.

This coating material has asphalt 1 as a main component, mica 2 is mixed therein, and various fillers such as talc and asbestos powder are added depending on the characteristics of use. Mica 2 is a mineral that exfoliates in layers, and those mixed into the main component of asphalt have an average aspect ratio of 90 or more in the particle size distribution. The aspect ratio r is the ratio of the wall thickness T to the planar length A of mica (r=A/
T), and the larger this ratio is, the better the vibration damping characteristics are.

This coating material is made by blending each composition, stirring it, and then forming it into a plate shape using a roll 4.
It is applied onto the flat surface of a steel plate 3 constituting the floor and pressed with a roll 4 to form a smooth layer. At this time, the mica 2 exfoliated into a thin film by roll forming becomes dispersed and oriented in a multilayered manner. In this case, the asphalt sheet has a multilayer structure of oriented mica. Therefore, this multilayer structure results in significant internal attenuation of vibrational energy. Furthermore, the packing density is relatively low.

This anti-vibration effect was tested in the following example, and the results were as follows.

Example 1 Straight asphalt, penetration 40/60 60 parts by weight Blown asphalt, penetration 20/30 40 parts by weight Asbestos 35 parts by weight Talc 70 parts by weight Mica (average aspect ratio 90) 20 parts by weight were prepared and asbestos was prepared. , talc, mica at 160℃
After putting it into a heating medium heating type kneader, it was stirred for several seconds.
Furthermore, while continuing to stir, straight asphalt and blown asphalt were added at the same time, and the mixture was stirred for 10 minutes to obtain a coating material.

A 2.0 m/m thick coating material was placed on a 0.8 m/m thick steel plate and left standing in an atmosphere of 150°C for 30 minutes to heat and fuse, forming a test piece of vibration-proof sheet.

Example 2 A coating material having the same components as in Example 1 was similarly heat-welded onto a steel plate with a thickness of 0.8 m/m, and a test piece of a vibration-proof sheet with a thickness of 1.6 m/m was formed in the same manner.

Comparative Example Straight asphalt, penetration 40/60 60 parts by weight Blown asphalt, penetration 20/30 40 parts by weight Asbestos 35 parts by weight Talc 70 parts by weight Mica (equivalent to aspect ratio 30) 20 parts by weight were prepared and used as an example. On the surface of the steel plate in the same process as 1.
A 20m/m anti-vibration sheet was formed.

Anti-vibration coefficient μ of these Examples 1, 2 and comparative examples
(μ: quantity representing the magnitude of internal attenuation of the material) was measured, and the results were as shown in the graph shown in Figure 3.

As can be seen from this graph, the vibration damping coefficient of the vibration isolating sheet in Example 1 is significantly improved compared to the comparative example when formed to the same thickness, and as in Example 2, the vibration damping coefficient of the vibration isolating sheet is significantly improved compared to the comparative example. It was also found that the loss coefficients were approximately the same or slightly larger than those of the comparative example.

In addition, as shown in Figure 4, when Example 1 and Comparative Example were compared and examined by the asphalt sheet sag test, it was found that Example 1 was heated on a 60° slope at 150°C for 30 minutes.
It was found that the amount of deformation of the anti-vibration sheet was significantly smaller than that of the comparative example.

As described above, according to the asphalt coating material according to the present invention, the vibration-proofing effect can be significantly improved, and even if the sheet thickness is made thinner, substantially the same vibration-proofing effect can be achieved, so that the asphalt coating material can be made lighter. It also makes it possible to

[Brief explanation of the drawing]

Fig. 1 is an explanatory view showing the asphalt sheet forming process, Fig. 2 is a schematic side sectional view of the asphalt sheet according to the present invention, Fig. 3 is an explanatory view of mica used in the present invention, and Fig. 4 is an explanatory view of the asphalt sheet according to the present invention. Also, a graph showing the vibration damping coefficient corresponding to a change in the fusion temperature of a conventional asphalt sheet, and FIG. 5 is a schematic explanatory diagram showing a drooping test of an asphalt sheet. 1: Main component of asphalt, 2: Mica, 3: Steel plate constituting the floor, etc.

Claims (1)

[Claims] 1. An asphalt coating material characterized by dispersing thin mica having an aspect ratio of 90 or more in the particle size distribution in a multi-layered manner as a main component of asphalt.