JPH10296829A - Coloring concentration regulating method for transparent colored resin sheet, and manufacture of transparent colored resin sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the regulation of the coloring concentration by changing a thickness ratio between both layers of transparent colored resin layer wherein a coloring agent- containing amount is fixed, and a transparent colored resin sheet on which a transparent colorless resin layer are integrated. SOLUTION: When a transparent colored resin layer wherein a coloring agent-containing amount is fixed, and a transparent colorless resin layer are integrated by a co-extrusion, and a transparent colored resin sheet of a specified thickness is formed, the coloring concentration regulation is performed by changing a thickness ratio between both layers. Therefore, the control of the coloring concentration can be easily performed without changing the coloring agent-containing amount of the transparent colored resin layer. Also, the transparent colored resin sheets of the same thickness and different coloring concentrations can be continuously produced without changing the resin material. For the layer constitution, a constitution wherein a colored resin layer and a colorless resin layer are integrated, a constitution wherein a colorless resin layer is pinched with colored resin layers and a constitution wherein a colored resin layer is pinched with colorless resin layers, etc., can be counted. In addition, a constitution wherein a transparent functional resin layer of an ultraviolet absorbent, anti-static agent, and an anti-bacterial agent, etc., is added, is available as well.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for adjusting the coloring density of a colored transparent resin sheet and a method for producing the same.

[0002]

2. Description of the Related Art A transparent resin sheet is colored by a single-layer coloring method in which a desired coloring agent is contained in the entire thickness of the sheet in accordance with a desired coloring concentration. When the sheet thickness is constant, the coloring concentration is determined by the content of the coloring agent.
In order to match the coloring density of a sheet having a predetermined thickness with the original color sample by such a coloring method, the colorant content of the base resin must be adjusted by trial and error. In order to manufacture sheets having the same thickness and different coloring densities, a plurality of types of resin materials having different coloring agent contents must be prepared.

[0003]

As described above, in the conventional method, it is very complicated to adjust the coloring density of the sheet to the original color sample. Further, when manufacturing sheets having the same thickness and different coloring densities, it is troublesome to prepare a plurality of types of resin materials having different coloring agent contents.
The problem to be solved by the present invention is to provide a method for adjusting the color density of a transparent colored resin sheet in which the color density can be easily adjusted when the sheet thickness is constant, and a method for manufacturing such a transparent colored resin sheet. is there. It is another object of the present invention to easily change the color density when the sheet thickness is constant.

[0004]

In order to solve the above problems, the present invention provides a transparent colored resin sheet having a predetermined thickness by integrating a transparent colored resin layer having a fixed colorant content and a transparent colorless resin layer. In this, the color density is adjusted by changing the thickness ratio of the two layers. This method focuses on the fact that even if the colorant content of the transparent colored resin layer is constant, the coloring density changes as the thickness of the resin layer changes. Since the transparent colorless resin layer has substantially no color, the apparent coloring density of the entire sheet is
The content of the coloring agent is determined by the transparent coloring resin layer having a fixed content. By changing the thickness ratio between the two layers within a predetermined sheet thickness, the apparent coloring density of the entire sheet can be easily adjusted.

In the present invention, a transparent colored resin layer having a fixed colorant content and a transparent colorless resin layer are integrated by coextrusion to produce a transparent colored resin sheet having a predetermined thickness. From the viewpoint, during the extrusion, the coloring density is adjusted by changing the thickness ratio of the two layers within a predetermined finished sheet thickness. Therefore, it is possible to easily control the coloring concentration without changing the content of the coloring agent in the transparent coloring resin layer. According to this method, transparent colored resin sheets having the same thickness and different coloring densities can be continuously produced without changing the resin material.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION A case where a transparent colored resin layer having a fixed colorant content (hereinafter referred to as "colored resin layer") and a transparent colorless resin layer (hereinafter referred to as "colorless resin layer") are integrated by coextrusion. , As a layer configuration, a configuration in which two types and two layers of a colored resin layer and a colorless resin layer are integrated, a configuration in which two types and three layers in which a colorless resin layer is sandwiched by colored resin layers, and a colorless resin layer A configuration in which two or three layers sandwiched between layers are integrated is possible. Further, it is also possible to add a new transparent functional resin layer to these components, and to integrate three types, three types, four types, or three types, five layers. The functional resin layer, for example,
It is a resin layer having such functions by adding a function-adding agent such as an ultraviolet absorber, an antistatic agent, and an antibacterial agent to the resin.

[0007] It is also possible to add the above-mentioned function additive to the colored resin layer. However, depending on the compatibility of the colorant (dye) and the function-adding agent, one or both of them may bleed out, so that the functional resin layer and the colored resin layer are formed as separate independent resin layers. desirable. Further, it is also possible to add the above-mentioned function additive to the colorless resin layer. However, in order to adjust the color density, the thickness ratio may be changed within a predetermined thickness, so that the addition of a function additive to a resin layer having such a possibility of changing the thickness is not possible. It is not practical to keep the effect of the function additive constant. This is also true when a function additive is added to the colored resin layer.

[0008]

EXAMPLES The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples. In order to manufacture a 2.0 mm thick transparent colored resin sheet made of a modified polyester of brown smoke color (polyethylene terephthalate modified with cyclohexane dimethanol), two types of two layers of a colored resin layer and a colorless resin layer were integrally formed by coextrusion. It has become. In Examples 1 to 3, the total thickness of the sheet was 2.0 mm.
Among them, the thickness ratio of the colored resin layer having a colorant content of 0.05 wt% and the thickness ratio of the colorless resin layer were changed to be integrated by coextrusion. In Examples 4 and 5, the total thickness of the sheet was 2.0.
The thickness of the colored resin layer having a colorant content of 0.2 wt% and the thickness of the colorless resin layer in mm are changed to be integrated by coextrusion. The colored resin layer was extruded by a 30φ extruder,
The colorless resin layer was extruded by a 50φ extruder, and each was guided to a feed block and integrated. The thickness ratio between the colored resin layer and the colorless resin layer can be easily changed during the co-extrusion process. Also, for reference, the colorant was 0.2 wt.
% Was extruded into a single-layer transparent colored resin sheet having a thickness of 2.0 mm (Reference Example).

Table 1 shows the color difference of each transparent colored resin sheet of the example based on the transparent colored resin sheet of the reference example. The total light transmittance of each transparent colored resin sheet is also shown. It can be seen from Table 1 that the coloring density can be easily changed only by changing the thickness ratio of the coloring resin layer having the fixed coloring agent content and the colorless resin layer in the total sheet thickness fixed at 2.0 mm. I understand.

[0010]

[Table 1]

[0011]

As described above, according to the coloring density adjusting method of the present invention, it is possible to easily obtain transparent colored resin sheets having different coloring densities while fixing the entire thickness of the sheet. If a transparent colored resin sheet is produced by co-extrusion by applying the coloring concentration adjusting method according to the present invention, when producing sheets having the same thickness and different coloring concentrations, a resin material having the same colorant content is used. be able to. It is only necessary to prepare one type of colorant-containing resin material, and it is not necessary to change it, so it is necessary to efficiently produce transparent colored resin sheets with the same color density and different thicknesses in the same co-extrusion process. Can be.

Claims (3)

[Claims] 1. A sheet having a predetermined thickness by integrating a transparent colored resin layer having a fixed colorant content and a transparent colorless resin layer, wherein the thickness ratio of the two layers is changed. A method for adjusting the coloring density of a transparent colored resin sheet, characterized by the following. 2. A transparent colored resin layer having a fixed colorant content and a transparent colorless resin layer are integrated by coextrusion,
A method for producing a transparent colored resin sheet, characterized in that, during the extrusion, the coloring density is adjusted by changing the thickness ratio of the two layers within a predetermined sheet thickness. 3. The method for producing a transparent colored resin sheet according to claim 2, wherein the transparent colored resin layer and the transparent colorless resin layer are integrated with the transparent functional resin layer by coextrusion.