JPH06238842A - Novel surface hardness-modified plate and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide a surface hardness-modified plate wherein the surface hardness i.e., both the pencil hardness and the Taber abrasion hardness of a synthetic resin base plate are improved. CONSTITUTION:A surface hardness-modified plate comprises a synthetic resin base plate 1, a polymethyl methacrylate (PMMA) resin layer 2 and a hard coat layer 3 and is produced by a method wherein, after a coating layer of the PMMA-coated film, which is formed by applying a PMMA resin coating liquid to a release film, is thermally welded to the surface of the synthetic resin base plate 1 such as a polycarbonate plate, the release film is peeled off and a thermosetting resin hard coating agent is applied to the surface of the coating layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface hardness modifying plate suitable for use as a partition plate, a highway free fall prevention plate, a daylighting material and the like, which requires a certain degree of surface hardness, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, a synthetic resin plate such as a polycarbonate plate (PC) or a vinyl chloride plate (PVC) whose surface is hard-coated has been used for the above applications. These synthetic resin plates have the advantage that the surface is resistant to Taber-type wear hardness, but on the other hand, they have the following problems.

[0003]

That is, by directly hard-coating the above synthetic resin plate, the abrasion hardness of the Taber type is improved, but the scratching hardness of the indenting type such as the pencil hardness is Since the hardness of the substrate has a great influence, there is a problem that the effect is not so great.

The present invention has been made in view of the above problems, and an object of the present invention is to improve a surface hardness-improving plate and not only surface abrasion hardness but also scratching hardness for pressing and a manufacturing method thereof. To provide.

[0005]

[Means for Solving the Problems] To achieve this purpose,
The surface hardness-modified plate according to claim 1 of the present invention is characterized in that a polymethylmethacrylate resin (hereinafter referred to as PMMA) is formed on the surface of a synthetic resin substrate.
A coating layer and a hard coat layer (made of resin) are laminated and integrated. The PMMA resin used for this has the hardness that this resin has (3H or more in pencil hardness), and is a modified PMMA that is usually used for laminating PC and PVC.
It is not a resin with low hardness like resin. However, it is difficult to form such a PMMA resin into a film, and even if it is possible, it is difficult to handle such as lamination processing. Therefore, in the manufacturing method of claim 2 of the present invention, the two-layer film obtained by coating the release film with the PMMA resin solution on the surface of the synthetic resin substrate is integrated by fusion, and then the release film. The hard coat layer, the PMMA resin layer, and the synthetic resin substrate are integrated by peeling off and then applying a thermosetting resin type hard coating agent on the surface of the PMMA resin layer.

[0006]

The surface hardness modifying plate of the present invention is a "coating resin layer" (hereinafter referred to as PMMA resin layer) formed by laminating a PMMA resin coating layer on the surface of a synthetic resin substrate.
By improving the scratch hardness of a push-in type such as a pencil hardness by providing, a sufficient Taber-type surface abrasion hardness can be obtained by applying a hard coat layer of a hard coat agent on the PMMA resin layer. In this way, by providing the PMMA resin layer on the substrate, the pencil hardness can be improved by several ranks as compared with the case where the hard coat treatment is directly performed.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing one embodiment of the surface hardness modifying plate of the present invention. As shown in the drawing, the surface hardness modifying plate has a PMMA resin coating layer 4 thermally fused on the surface of a synthetic resin substrate 1. 3 shows a three-layer structure in which a hard coat layer 3 formed by applying a hard coat agent on the surface of a PMMA resin layer 2 integrally formed by adhesion is laminated and integrated. And a hard coat layer are laminated and integrated to form a 5-layer structure.

As the synthetic resin substrate, a thermoplastic resin such as polycarbonate, vinyl chloride or the like having a poor surface hardness and having various thicknesses and hues is used.

The PMMA resin layer 2 is basically made of PMMA resin excellent in hardness which is not modified with rubber or the like. This layer is preferably formed in a uniform surface shape, and if the thickness is too thin, it does not contribute to the surface hardness which is the gist of the present invention, so it is 3 μm or more, preferably 5 μm or more. Since it can be obtained, the film thickness is selected according to the application. When the synthetic resin substrate is inferior in weather resistance like a polycarbonate plate, this layer may contain an ultraviolet absorber or the like.

The hard coat layer 3 is formed of a hard coat agent of silicone, melamine resin, polyurethane, phosphazene resin, or other thermosetting resin depending on its use.

The three-layer and five-layer surface hardness modifying plate as described above is manufactured, for example, by the following method. First, P
A coating material is prepared by dissolving MMA resin in a solvent (toluene, xylene, ethyl acetate, etc.). And this paint P
The release film 5 such as ET is uniformly applied to one entire surface of the release film 5, and the solvent is dried and removed to form the transfer film of FIG. Then, the above transfer film (FIG. 2) is laminated on the synthetic resin substrate 1 with the PMMA resin coating layer 4 on the lower side, and the release film is peeled off after thermocompression-bonding integration with, for example, a hot press machine. The surface of the PMMA resin layer 2 is coated with a thermosetting resin type hard coat treatment agent and subjected to a hard coat treatment to obtain a surface hardness modified plate having the hard coat layer 3 integrated on the surface.

The surface hardness modifying plate can be easily adjusted to have a necessary abrasion hardness and a scratch hardness depending on the application by changing the film thickness of PMMA resin coated on the release film and the film thickness and type of the hard coat treatment layer. can get.

Table 1 below is a comparison of the test pieces of the present invention with the comparative examples and the synthetic resin substrates in terms of pencil hardness and haze after Taber abrasion. The test piece of the present invention is made of 2.5 mm thick polycarbonate (PC) and has a thickness of 8 μm.
m PMMA resin coating layer formed on one side 38
After a PET film having a thickness of μm was thermally fused and transferred so that the PMMA resin coating layer was on the PC surface side, a thermosetting hard coat agent such as phosphazene resin (PP
Z) was applied to a dry thickness of 10 μm to integrate a hard coat layer into a three-layer structure test piece. Comparative Example 1 is a two-layer structure piece of PC and PMMA resin layer, Comparative Example 2
And 3 are two-layer structure pieces of PC and PPZ. The pencil hardness was measured according to JIS-K-5400, and Taber abrasion and haze were measured according to JIS-K-6735.

[0014]

[Table 1]

From Table 1, the test piece was 2 more than Comparative Examples 2 and 3 in which the polycarbonate plate was hard-coated directly.
It can be seen that the pencil hardness is ~ 3H. Further, the haze after abrasion of the Taber shows the same value, and it can be seen that there is no influence of the PMMA resin layer. Therefore, it can be seen that the surface hardness modified plate of the present invention has a pencil hardness which is several ranks higher than that obtained by directly hard-coating the substrate.

[0016]

As is apparent from the above description, the surface hardness modifying plate of the present invention has a structure in which a PMMA resin layer and a hard coat layer are laminated and integrated on the surface of a synthetic resin substrate,
By providing the PMMA resin layer, it is possible to obtain a surface hardness-modified plate having high pencil hardness and Taber abrasion hardness, which are difficult to obtain with only the hard coat layer. Further, since the PMMA resin layer is integrated by transferring the PMMA resin coated layer onto the substrate, it is difficult to form a film in the PMM.
The A resin can be easily laminated and integrated.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a surface hardness modifying plate of the present invention.

FIG. 2 is a cross-sectional view showing an example of the PMMA resin transfer film of the present invention.

[Explanation of symbols]

 1 synthetic resin substrate 2 PMMA resin layer 3 hard coat layer 4 PMMA resin coated layer 5 release film

Front page continued (72) Inventor Akira Matsui 2-3-13 Azuchi-cho, Chuo-ku, Osaka Takiron Co., Ltd. (72) Inventor Morihiro Seko 2-3-3 Azuchi-cho, Chuo-ku, Osaka Takiron shares In the company

Claims (2)

[Claims] 1. A surface hardness modifying plate obtained by laminating and integrating a polymethylmethacrylate resin coating layer and a hard coat layer on the surface of a synthetic resin substrate. 2. A release film is peeled off after a polymethylmethacrylate resin coated film formed by coating a release film with a polymethylmethacrylate resin solution is integrated on the surface of a synthetic resin substrate by fusion bonding. Then, a method for producing a surface hardness modified plate, which comprises applying a thermosetting resin type hard coating agent to the surface of the polymethylmethacrylate resin layer to form a hard coating layer.