JP2001131504A - Marking film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a marking film which can improve the adhesion of a coating film layer to a substrate layer with the passage of time and prevent the bleedout of a stabilizer. SOLUTION: This marking film comprising a coating film layer, a synthetic resin substrate layer, and an adhesive layer which are laminated in the order, wherein the coating film layer comprises an upper coating layer forming the surface of the film and a lower coating film layer adjacent to the substrate layer. The concentration of a stabilizer in the coating layer has the relation of (the concentration in the upper coating layer < the concentration in the lower coating layer.)

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a marking film used for, for example, outdoor and indoor advertising stickers and display stickers.

[0002]

2. Description of the Related Art In general, a marking film is formed by using a polyvinyl chloride resin film as a base layer and coloring the base layer by kneading a pigment according to the purpose, or by printing on one side of the base layer. Apply coating to form a coating layer, apply an appropriate pressure-sensitive and / or heat-sensitive adhesive to the opposite surface according to the application to form a pressure-sensitive adhesive layer, and further use a release paper to protect the pressure-sensitive adhesive layer. In use, the release material layer is peeled off and the pressure-sensitive adhesive layer is attached to a predetermined location. Marking films are often used outdoors, and are used for signboards, advertising towers, shutters, show windows, etc .; advertising stickers used for vehicles such as automobiles and motorcycles, and decorative stickers used for ships such as motor boats; It is used for applications such as display signs used for traffic signs, road signs, and information boards. For this reason, it is necessary that the marking film has weather resistance and has appropriate flexibility for attaching to a cubic curved surface.

[0003] Since the conventional marking film uses a polyvinyl chloride resin film as a base material layer, hydrogen chloride gas and dioxin are generated at the time of incineration disposal, so that it cannot be treated with simple incineration equipment. There was a problem that the durability of the incineration equipment was reduced. Therefore, recently, there has been an increasing demand for a low environmental load type marking film that can be processed by a simple incineration facility. For example, the marking film described in JP-A-8-157780 uses a polyolefin-based resin film as a base material layer and can be incinerated and discarded.

Further, as a marking film provided with various coating layers, a film described in Japanese Patent Application No. 10-53600 has been proposed.

[0005]

In a marking film having a coating layer, it is necessary to incorporate a large amount of a stabilizer into the coating layer in order to improve the temporal adhesion between the coating layer and the substrate layer. Yes, but large amounts of stabilizers cause bleed out and cloud the film surface.

An object of the present invention is to provide a marking film capable of improving the adhesiveness of a coating layer and a substrate layer over time and preventing bleed-out of a stabilizer.

Means for Solving the Problems The present inventor has studied to solve the above-mentioned problems, and as a result, the coating layer is composed of an upper coating layer on the surface and a lower coating layer on the substrate layer side, By adding more stabilizer to the lower coating layer than to the upper coating layer, the adhesion of the coating layer and the base layer over time is improved and the bleed out of the stabilizer to the coating layer surface is effective. The present invention was completed.

That is, the marking film according to the present invention comprises a coating layer, a synthetic resin base layer, and an adhesive layer laminated in this order, and the coating layer forms an upper coating layer and a base layer which form the film surface. It comprises at least two adjacent lower coating layers and the concentration of the stabilizer in the coating layer is such that the concentration in the upper coating layer <the concentration in the lower coating layer.

Hereinafter, the constituent layers of the marking film according to the present invention will be described in detail.

First, regarding the synthetic resin substrate layer,
As the film for the base layer, a general film such as a soft polyvinyl chloride film or a soft polyolefin resin film can be used. Among them, a film made of a soft polyolefin-based resin that can be easily incinerated is preferable from the viewpoint of reducing environmental load.

A preferred example of the polyolefin-based resin for the base layer is 20 to 100% by weight of a soft polypropylene-based resin (hereinafter abbreviated as PP) and 0 to 80% by weight of another polyolefin-based resin. Soft PP
The system resin has a weight average molecular weight (Mw) of 80,000 to 500,000,
And the elution amount at 10 ° C. or less by the cross fractionation method is 45 to 8
0% by weight;
5% by weight;
0% by weight;
It is 35% by weight. Titanium oxide may be further added to the above composition in an amount of 50 to 300 parts by weight based on 100 parts by weight of the PP resin.

This PP-based resin film has a very flexible and concealing property and can form a base layer having an appropriate tear property, and the tertiary curved surface workability and tear property of the marking film are remarkably improved. Therefore, it is particularly preferable. The film for the substrate layer may be a single layer or a multilayer.

Examples of such a flexible PP resin include "PER" manufactured by Tokuyama Corporation, "Cataroy" manufactured by Montell JPO, "Zeras" manufactured by Mitsubishi Chemical Corporation, and "Excelen" manufactured by Sumitomo Chemical Corporation. All of which are used in the present invention.

[0013] The film for the base material layer is prepared by compounding the above-mentioned additives to the resin for the base material layer and then forming the compound by a conventionally used T-die method or inflation method. Can be obtained by Since the obtained substrate layer film generally has a low surface tension, it is desirable to improve the adhesion of the coating layer and the pressure-sensitive adhesive layer by a surface modification treatment such as a corona treatment.

Next, as the resin paint for the coating layer, an acrylic resin paint, a urethane resin paint, a polyester resin paint or a fluorine resin paint having good weather resistance can be used. The total thickness of the coating layer is preferably 10 to 6
0 μm, and the thickness of the lower coating layer is preferably 1 to 15 μm.
m. When the thickness of the lower coating layer is less than 1 μm, it is difficult to prevent the undercoat from being transparent, and when the total thickness of the coating layer exceeds 60 μm, it tends to be inferior in followability to a cubic curved surface.

The paint preferably contains 5 to 200 parts by weight of a pigment based on 100 parts by weight of the paint resin. If the coating layer is composed of only one layer having a thickness of 10 to 40 μm, the base layer can be seen through the same layer, so that the target color and the applied color are different. A problem arises in that uniformity of the coated surface cannot be obtained due to the difference in film thickness.

Therefore, the coating layer is composed of at least two layers, an upper coating layer forming the film surface and a lower coating layer adjacent to the substrate layer, and the concentration of the stabilizer in the coating layer is reduced. The relationship of concentration in the upper coating layer <concentration in the lower coating layer is established. As a result, the base material layer can be prevented from being seen through, and a desired color tone and uniform appearance can be obtained.

As the pigment to be blended in the upper and lower coating layers, generally used organic pigments having good weather resistance are suitable.

Examples of stabilizers to be incorporated in the coating layer include ultraviolet absorbers such as "Tinuvin 384" manufactured by Ciba Specialty Chemicals; hindered amine light stabilizers such as "Chimassorb 944" and "Tinuvin 622" manufactured by Ciba Specialty Chemicals. It may be. Each of the stabilizers may be used alone, but is usually used in combination.

The concentration of the stabilizer is usually preferably from 0.1 to 1.5 parts by weight based on 100 parts by weight of the resin component of the coating composition. Preferably, there is. In the present invention, the concentration of the stabilizer is determined so that the relationship of the concentration in the upper coating layer <the concentration in the lower coating layer is satisfied. For example, when the concentration of the stabilizer in the undercoat layer is 2
To 6 parts by weight and the concentration in the upper coating layer in the range of 0.1 to 1.5 parts by weight. By distributing the stabilizer concentration in this manner, it is possible to improve the temporal adhesion between the coating layer and the base material layer and to prevent the bleed out of the stabilizer.

The thickness of the upper coating layer and the thickness of the lower coating layer are preferably not less than the thickness of the lower coating layer from the viewpoint of physical properties and weather resistance of the entire film.

The thickness of the lower coating layer is preferably 1 to 15 μm.
It is. If the thickness of the undercoat layer is small, the effect of preventing the undercoat from being transparent becomes small, and it becomes difficult to obtain a desired color toning and a uniform appearance. The total thickness of the upper and lower coating layers is 6
If it exceeds 0 μm, the ability to follow an adherend such as a cubic curved surface of the film will be poor.

The upper and lower coating layers are formed by applying a resin coating by a gravure coater, comma coater, reverse coater, knife coater, spray gun, screen printing or the like.

The thickness of the base material layer is 20 to 150 in total.
μm, preferably 40 to 60 μm, is suitable. 20μ
If it is less than m, the film itself is too soft, which makes the construction difficult and insufficient in strength. If it exceeds 150 μm, on the contrary, it becomes too hard, and the followability to an adherend such as a cubic curved surface becomes poor.

Next, regarding the pressure-sensitive adhesive layer, the pressure-sensitive adhesive used in the same layer may be either an acrylic resin-based or rubber-based pressure-sensitive adhesive, but the marking film is assumed to be used outdoors. For this reason, acrylics having high weather resistance are preferable.

The pressure-sensitive adhesive may be a solvent-type acrylic pressure-sensitive adhesive polymerized in a solvent, an emulsion-type pressure-sensitive adhesive polymerized in water, or a bulk polymerization-type pressure-sensitive adhesive obtained by irradiating a monomer mixture with ultraviolet rays. You may. The thickness of the pressure-sensitive adhesive layer is preferably from 20 to 50 μm. In general, a marking film is prepared by applying a pressure-sensitive adhesive to a release material by a quantitative coating method such as a reverse coating method, drying it by heating, and then adhering it to the opposite side of the base material layer with a coating layer formed on one side. It is manufactured by laminating agent layers.

The release material layer for protecting the pressure-sensitive adhesive layer of the marking film is not particularly limited, and for example, a silicone-coated release paper can be used.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist.

<Example 1> A homo PP resin having a melt index (3.9 g / 10 min) was used as the resin for both outer layers, and a weight average molecular weight of 200,000 was used as the material for the intermediate layer. Soft PP whose elution amount is 69% by weight at 10 ° C or less, 11% by weight at 10 ° C or more and 70 ° C or less, 2% by weight at 70 ° C or more and 95 ° C or less, and 18% by weight at 95 ° C or more and 125 ° C or less. Using a blend of 80 parts by weight of titanium oxide with respect to 100 parts by weight of the base resin,
These were formed into a sandwich shape with a multilayer T-die extruder to a thickness of 50 μm (both outer layer thickness: 8 μm each, intermediate layer thickness: 34 μm), and a double-sided corona treatment (42 × 10 ⁻⁵ N) was performed in-line. / Cm). The obtained film was used as a substrate layer, a lower coating layer was formed on one side thereof, and an upper coating layer of the same color as this was formed on the lower coating layer.

The upper and lower coating layers were formed as follows. As a coating composition for the upper coating layer, 100 parts by weight of a urethane-based resin coating “Planit U # 700” (manufactured by Dainippon Paint Co., Ltd.) and 6.5 parts by weight of a curing agent “Coronate 2094” (manufactured by Nippon Polyurethane Co., Ltd.) And 10 parts by weight of a paint softening agent “Auto High Flex” (manufactured by Dainippon Paint Co., Ltd.), and blue by adding cyanine blue. Further, hindered amine is added to 100 parts by weight of the resin component of the urethane resin paint. 0.2 parts by weight of a light stabilizer "Tinuvin 622" (manufactured by Ciba Specialty Chemicals) and 0.2 parts by weight of an ultraviolet absorber "Tinuvin 327" (manufactured by Ciba Specialty Chemicals) are added, and a coating composition is added. Was prepared. Further, as the coating composition for the lower coating layer, 2 parts by weight of the hindered amine light stabilizer "Tinuvin 622" and 1 part by weight of the ultraviolet absorber "Tinuvin 327" are used with respect to 100 parts by weight of the resin component of the urethane-based resin coating. The same coating composition as that of the upper coating layer was prepared except that was added. Then, a coating composition for a lower coating layer is applied to one side of the base material layer with a gravure coater to a thickness of 3 μm to form a lower coating layer, and the coating composition for an upper coating layer is sprayed on the lower layer. An upper coat layer was formed by coating with a coater to a thickness of 20 μm.

An adhesive layer was formed on the substrate layer opposite to the coating layer, and a release material layer was formed thereon. The adhesive layer is
A two-component crosslinkable acrylic pressure-sensitive adhesive was applied to a silicone-coated release paper using a comma coater so as to have a dry thickness of 40 μm. This was laminated on the surface of the substrate layer opposite to the surface on which the coating layer was laminated. Thus, a marking film was produced.

<Example 2> A hindered amine light stabilizer "Tinuvin 62" was added to the undercoat layer layer coating composition.
2) A marking film was obtained in the same manner as in Example 1 except that only 3 parts by weight was used.

Example 3 A homo PP resin having a melt index (3.9 g / 10 min) was used as the resin for both outer layers, and a weight average molecular weight of 250,000 was used as the material for the intermediate layer. Soft PP having an elution amount of 48% by weight at 10 ° C or less, 19% by weight at 10 ° C or more and 70 ° C or less, 5% by weight at 70 ° C or more and 95 ° C or less, and 28% by weight at 95 ° C or more and 125 ° C or less. Using a mixture of 100 parts by weight of titanium oxide with respect to 100 parts by weight of a base resin, these were formed into a sandwich film so as to have a thickness of 50 μm by a multilayer T-die extruder, and both sides were corona treated in-line. (42 × 10 ⁻⁵ N / cm). A marking film was obtained in the same manner as in Example 1 except that the obtained film was used as a substrate layer.

Example 4 This example shows an example of manufacturing a marking film made of a polyvinyl chloride resin. Polyvinyl chloride resin (“PSH-10” manufactured by Kanegafuchi Chemical Co., Ltd.) 100
35 parts by weight of a plasticizer ("P-300" manufactured by Asahi Denka Co., Ltd.), 10 parts by weight of a stabilizer ("AC-110" manufactured by Asahi Denka Co., Ltd.), and a white pigment ("VT-771" manufactured by Dainichi Seika Co., Ltd.) )) 45 parts by weight and a solvent ("Solvesso" manufactured by Mitsubishi Chemical Corporation) 80
By weight, an organosol was prepared. This sol was applied on alkyd resin coating process paper with a comma coater and dried to obtain a film having a thickness of 60 μm. The drying condition was 180 ° C. × 7 minutes. A marking film was obtained in the same manner as in Example 1 except that the obtained film was used as a substrate layer.

Example 5 A resin paint for a coating film layer was made of a fluororesin paint "Duflon" (manufactured by Nippon Paint Co., Ltd.).
A marking film was obtained in the same manner as in Example 1 except that the marking film was changed.

<Comparative Example 1> A hindered amine light stabilizer "Tinuvin 622" (manufactured by Ciba Specialty Chemicals) was added to a resin composition of a urethane-based paint based on 100 parts by weight of a stabilizer of a paint composition for an undercoat layer. A marking film was obtained in the same manner as in Example 1, except that 0.2 parts by weight and 0.3 parts by weight of the ultraviolet absorber "Tinuvin 327" (manufactured by Ciba Specialty Chemicals) were used.

<Comparative Example 2> A hindered amine light stabilizer "Tinuvin 622" (manufactured by Ciba Specialty Chemicals) 4 was added to a urethane-based coating composition based on 100 parts by weight of a resin component. A marking film was obtained in the same manner as in Example 1 except that the weight part was changed to 4 parts by weight and the ultraviolet absorber "Tinuvin 327" (manufactured by Ciba Specialty Chemicals).

<Comparative Example 3> Using only the coating composition for the lower coating layer, the composition was spray-coated with a spray gun coater to a thickness of 20 μm.
Example 1 except that only one coating layer was formed by coating with
A marking film was obtained in the same manner as described above.

Performance Evaluation Test The marking films obtained in the above Examples and Comparative Examples were evaluated for the following items. Table 1 shows the evaluation results.

<Coating Uniformity> After the coating layer was laminated on the substrate layer, the appearance of the finished coating film was evaluated according to the following criteria.・ ・ ・: Uniform and good appearance of coating film ×: remarkable coating unevenness occurs and coating film cannot be formed as a product <Adhesion of coating over time> Marking film is applied to aluminum plate The exposed test piece was exposed for 300 hours with a super UV tester manufactured by Dainippon Plastics Co., Ltd.
Cross-cutting was performed in a square of mm, and a cellophane tape peeling test was performed on 100 of the obtained cut pieces to evaluate the adhesion.

Adhesion = peeling number / 100 (smaller value is better, better value is 0) <Haze of coating film> After storing the marking film in an oven at 40 ° C. for one month, the appearance of the marking film is shown below. Evaluation was based on criteria.

◎: no change in appearance Δ: slight clouding is observed X: significant clouding is generated

[Table 1]

[0042]

According to the present invention, the coating layer is composed of the upper coating layer on the surface and the lower coating layer on the substrate layer, and the concentration of the stabilizer is lower than that of the upper coating layer. By making it higher, the temporal adhesion between the coating layer and the base layer can be greatly improved, and bleed out of the stabilizer onto the surface of the coating layer can be effectively prevented.

Claims (1)

[Claims] 1. A coating film layer, a synthetic resin base material layer, and a pressure-sensitive adhesive layer are laminated in this order, and the coating film layer forms an upper coating film layer forming a film surface and a lower coating film layer adjacent to the base material layer. A marking film comprising at least two layers, wherein the concentration of the stabilizer in the coating layer is in a relationship of "concentration in the upper coating layer <concentration in the lower coating layer".