JP7602788B2 - Method for producing rubber winding liners - Google Patents

Description

This invention relates to a liner for winding rubber.

When winding up rubber materials, a cushioning material called a liner is used to prevent the rubber from sticking together (see Patent Document 1, etc.). Liners are made of, for example, cloth or laminated film. Here, a laminated film is a film made by combining multiple materials in multiple layers.

JP 2019-026964 A

However, with cloth liners, the cloth threads can break, and with laminated films, the film surface can crack or the base material inside can peel off, which can cause problems with foreign matter getting into the rubber components.

Figure 4 shows an example of a laminated film used in conventional liners. Figure 4(a) shows a film made by combining multiple materials into many layers. Figures 4(b) and (c) show films made by laminating composite materials (urethane, cloth, film, etc.) onto the laminated film of Figure 4(a) as the core material.

Figure 5 shows a tear experiment of the laminated film in Figure 4(a).

Figures 5 (a) and (b) show the case where the tear direction is horizontal. One of the materials that composes the laminated film has a biaxial (vertical and horizontal) or triaxial (vertical and both diagonal) structure, and is in a lattice or mesh shape. Experiments were conducted three times with the cuts on the intersections of the lattice, and three times with the cuts between the lattice. The average tear strength (N) at the maximum convex point was 57.0 N, and the average for all concaves and convexes was 29.0 N.

Figure 5 (c) shows the case where the tear direction was vertical. Experiments were conducted three times with the cuts on the intersections of the lattice, and three times with the cuts between the lattice. The average tear strength (N) at the maximum convex point was 45.5N, and the average for all concaves and convexes was 27.0N.

Furthermore, the substrate of the laminated film peels off at the torn area (see FIG. 5(b)), and the surface of the film cracks at the torn area (see FIG. 5(c)). This may cause foreign matter to get into the rubber member .

The present invention therefore aims to propose a rubber winding liner that is unlikely to cause foreign matter to become mixed into the rubber material even if it is damaged.

The first aspect of the present invention is a rubber winding liner that includes an amorphous film.

A second aspect of the present invention is the rubber winding liner according to the first aspect, which has a single structure of the amorphous film, and the amorphous film is made of an amorphous resin in the form of a film.

A third aspect of the present invention is the rubber winding liner according to the second aspect, wherein the amorphous film has a unitary structure in which an amorphous resin is formed into a film shape and the surface is embossed.

A fourth aspect of the present invention is a rubber winding liner according to any one of the first to third aspects, which is formed by laminating a plurality of materials together with the amorphous film as a core material.

A fifth aspect of the present invention is a rubber winding liner according to any one of the first to fourth aspects, which is used for winding unvulcanized rubber.

According to each aspect of the present invention, by using an amorphous film, even if it is damaged, it will tear gradually without cracking or peeling off, reducing the possibility of foreign matter being mixed into the rubber component.

FIG. 1 is a diagram showing an example of the configuration of a rubber winding liner according to an embodiment of the present invention. FIG. 2 is a diagram showing a specific example of the configuration of the rubber winding liner of FIG. 1. FIG. 2(a) shows a tearing experiment of the amorphous film. An example of a laminated film used in a conventional liner is shown below. FIG. 4(a) shows a tear experiment of the laminated film.

Below, an embodiment of the present invention will be described with reference to the drawings. Note that the present invention is not limited to this embodiment.

FIG. 1 is a diagram showing an example of the structure of a rubber winding liner according to an embodiment of the present invention. Referring to FIG. 1(a) and (b), the rubber winding liner 1 is a film-like amorphous material, and has a single structure of an amorphous film. Also, FIG. 1(c) and (d) show a rubber winding liner 3 made by laminating a composite material (urethane, cloth, film, etc.) to the rubber winding liner of FIG. 1(a) and (b) as a core material. In FIG. 1(c) and (d), an amorphous film 7 made by filming an amorphous material is used as a core material, and other materials 5 and 9 are laminated to the core material. The core material does not need to be surface-treated, and may be surface-treated, for example, by blasting or atmospheric plasma treatment.

Figure 2 is a diagram showing a specific example of the structure of the rubber winding liner of Figure 1. Referring to Figure 2(a), one example of the rubber winding liner of the present invention is a film-like amorphous resin, and has a single structure of an amorphous film. Specifically, NC-PET (registered trademark) was used. Figures 2(b) and (c) show a liner made by laminating a composite material (urethane, cloth, film, etc.) to the amorphous film 11 of Figure 2(a) as a core material.

If wrinkles or scratches occur in the liner when the rubber material is being wound up, the rubber material will adhere to the liner from those points, causing problems such as tearing or breaking the base material or introducing foreign matter into the rubber material.

Figure 3 shows a tear experiment of the amorphous film in Figure 2(a).

Figure 3 (a) shows the case where the tear direction is horizontal. When an experiment was performed three times with a cut, the tear strength (N) was 84N, 55N, and 66N at the maximum convex point, averaging 68.3N, and 44N, 34N, and 40N for the total unevenness average, averaging 39.3N.

Figure 3 (b) shows the case where the tear direction is vertical. When an experiment was performed three times with a cut, the tear strength (N) was 47N, 48N, and 49N at the maximum convex point, averaging 48.0N, and 37N, 38N, and 39N for the total unevenness average, averaging 38.0N.

Compared to the case shown in Figure 5, the tear strength is greater in both the vertical and horizontal directions, and the material has the ability to be used as a liner. Note that the tear strength in the diagonal direction (N) was 37.3 N on average for the maximum convex point and 17.5 N on average for all concaves and convexes in Figure 4(a), whereas in Figure 2(a) it was 102.3 N on average for the maximum convex point and 55.3 N on average for all concaves and convexes.

Furthermore, the amorphous film is flexible and suitable as a core material, and because it is amorphous, it breaks gradually at the torn area, the torn surface is smooth, and it does not peel or crack. This reduces the possibility of foreign matter being mixed into the rubber component.

The amorphous film in Fig. 2(a) shows at least the same performance in evaluation experiments such as peelability evaluation (rubber adhesion test), water/gasoline impregnation evaluation (change in performance when impregnated with water/gasoline), and bending resistance evaluation (resistance when the sample is made into a loop and compressed). Therefore, it is not destroyed by water resistance or solvent resistance, and it is not destroyed by rubber cement used in tire manufacturing. Furthermore, when used as a core material, the adhesive strength without surface treatment is 1.42 (N/25mm) for the ones in Fig. 2(b) and (c), while it is 1.27 (N/25mm) for the ones in Fig. 4(b) and (c), and the adhesive strength can be improved. Furthermore, when the surface is treated by blasting + atmospheric plasma treatment, the adhesive strength is 3.09 (N/25mm) for the ones in Fig. 2(b) and (c), while it is 2.63 (N/25mm) for the ones in Fig. 4(b) and (c), and the adhesive strength can be greatly improved.

1, 3 Rubber winding liner, 5, 9 Other materials, 7, 11 Amorphous film

Claims (1)

1. A method for producing a rubber winding liner, comprising:
The method for producing the rubber winding liner comprises laminating another material to an amorphous film formed by forming an amorphous material into a film shape, which is used as a core material .

Images