JP2000318089A - Outdoor sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an outdoor sheet of novel constitution excellent in weatherability and antistaining properties, generating no ply separation. SOLUTION: A silicone resin coating layer 4 containing photocatalyst particles is formed on the surface of a sheet main body 1 through a primer layer 2 based on an ethyleneimine modified polymer and an intermediate layer 3 based on silicone varnish. The sheet main body pref. comprises soft PVC and the photocatalyst particles pref. comprise titania.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outdoor sheet, and more particularly to a sheet having weather resistance and stain resistance suitable for use in a tent, a greenhouse, and the like.

[0002]

2. Description of the Related Art In general, flexible PVC is used as a sheet for such an application. In recent years, a flexible PVC has been used as a base material, and an acrylic resin, an acrylic / fluorine copolymer, a vinylidene fluoride, etc. (PVDF)
Applying one or more layers of coating, etc.,
Products that have been improved in weather resistance by heat-sealing a two-layer coextruded film of acrylic and PVDF have been commercialized, but their antifouling properties are not always sufficient and they deteriorate over time after long-term use. There was a problem.

To solve this problem, Japanese Patent Application Laid-Open No.
In JP-A-78454, a hydrophilic surface layer containing photocatalyst particles is provided on the surface of a sheet body, and further, an intermediate layer is provided between the sheet body and the hydrophilic surface layer to protect the sheet body from a redox reaction caused by a photocatalyst. It has been proposed. According to this conventional technology, the sheet surface can be self-cleaned with rainwater or the like by forming the hydrophilic surface layer, and the hydrophilicity can be restored by irradiation with ultraviolet light by containing the photocatalyst particles. It is said that hydrophilicity can be maintained over a period. Furthermore, the photocatalyst particles undergo an oxidation-reduction reaction upon irradiation with ultraviolet rays, thereby decomposing the dirt component attached to the surface, and providing the intermediate layer protects the sheet body from the oxidation-reduction reaction by the photocatalyst particles.

[0004]

Although the formation of the intermediate layer is not an essential requirement in the above-mentioned prior art, when the hydrophilic surface layer is directly laminated on the surface of the sheet body, the oxidation by the photocatalyst is difficult. Since the sheet body is deteriorated by the reduction reaction, it is considered that it is practically essential to interpose an intermediate layer serving as a barrier layer between the sheet body and the hydrophilic surface layer.

However, as a sheet body, soft PV
When C is used, the plasticizer contained in the soft PVC leaches out to the surface, so that the adhesiveness with the intermediate layer becomes insufficient. According to the above-mentioned prior art, an aluminum deposited film or a film containing aluminum particles is used for the intermediate layer,
In any case, the adhesion property is greatly impaired by the plasticizer leached on the surface of the soft PVC, which causes delamination.

When an aluminum vapor-deposited film or a film containing aluminum particles is used as the intermediate layer, the adhesion between the intermediate layer and the hydrophilic surface layer is not good, and delamination between these layers is a problem. .

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems in the prior art, and to provide an outdoor sheet having a novel structure which is excellent in weather resistance and antifouling property and does not cause delamination. And

That is, the outdoor sheet according to the present invention comprises:
It is characterized in that a silicone resin paint layer containing photocatalyst particles is formed on the surface of the sheet body via a primer layer mainly composed of an ethyleneimine-modified polymer and an intermediate layer mainly composed of silicone varnish.

[0009] The sheet body is preferably soft PVC and the photocatalytic particles are preferably titania.

[0010]

FIG. 1 shows the structure of an outdoor sheet according to the present invention. A paint layer 4 is formed on the surface of a sheet body 1 with a primer layer 2 and an intermediate layer 3 interposed therebetween.

As the sheet body 1, a flexible PVC film, a fluorine-based film, a PET film, an OPP film or the like can be used. According to the present invention, when a flexible PVC is used as described later, a plasticizer is applied to the surface thereof. It is preferable to use a soft PVC which is advantageous in terms of workability and cost since leaching is prevented.

The primer layer 2 formed on the surface of the sheet body 1 is mainly composed of an ethyleneimine-modified polymer. Here, the ethyleneimine-modified polymer is obtained by grafting polyethyleneimine (PEI) to a side chain of a polymer such as an acrylic polymer as a main chain, and has a chemical structure represented by Formula 1.

[0013]

(Equation 1)

Since the ethyleneimine-modified polymer has a grafted primary amino group on a side chain, the primer layer 2 exhibits good adhesion to the sheet body 1 such as a soft PVC or the like and the intermediate layer 3. Those having an acrylic main chain are particularly suitable for use as outdoor sheets because of their excellent weather resistance.

Polyethyleneimine is a ring-opened polymer produced from monoethylamine (H2NCH2CH2OH) as a starting material and starting from ethyleneimine or a derivative thereof, and has a chemical structure represented by Formulas 2 to 4.

[0016]

(Equation 2)

[0017]

(Equation 3)

[0018]

(Equation 4)

The intermediate layer 3 is made of a silicone varnish having a chemical structure represented by Formula 5. Here, the silicone varnish is CH3SiO3 / 2, (CH3) 2SiO, (CH3) SiO2, (CH3) 3SiO1 /
Methylsilicone, which is a copolymer combining methyl groups such as 2NO, and in addition to these methyl groups, C6H5SiO2 / 3, (C6H
5) Methylphenylsilicone, which is a copolymer combining phenyl groups such as 2SiO, (CH3) (C6H5) SiO, or copolymers of these with alkyd resins, polyester resins, epoxy resins, acrylic resins, urethane resins, etc. It means a modified silicone-based resin paint that is a united product.

[0020]

(Equation 5)

The intermediate layer 3 has good adhesion to the primer layer 2 because the ethyleneimine-modified polymer has a grafted primary amino group in a side chain, and the intermediate layer 3 is bonded to the silicone resin coating layer 4 by ionic bonding between silicone resins. Has good adhesion.

The silicone resin coating layer 4 contains photocatalyst particles. As the photocatalyst particles, titanium oxide (titania), particularly amorphous titania is preferably used, but other metal oxides such as ZnO, SnO2, XrTiO3, WO3, Bi2O3, and Fe2O3 may be used. These photocatalyst particles receive ultraviolet rays to excite the redox reaction to decompose and remove dust substances attached to the sheet surface, and impart antifouling properties by maintaining the sheet surface hydrophilic. Also,
When silica is further contained in the silicone resin coating layer 4, the hydrophilicity of the sheet surface can be further improved, which is a preferable embodiment.

Hereinafter, examples of the present invention will be described in comparison with comparative examples, thereby demonstrating that the outdoor sheet of the present invention has excellent antifouling properties.

With respect to 100 parts by weight of the PVC resin (degree of polymerization: 1400), 60 parts by weight of DOP as a plasticizer, 4 parts by weight of a barium zinc compound as a stabilizer, and 20 parts by weight of titanium oxide as a pigment are added. The sheet body 1 having a thickness of 0.5 mm is defined as a sheet body 1, and a grafted product of an acrylic copolymer and polyethyleneimine is applied to the surface of the sheet body 1 to a thickness of 0.1 mm to form a primer layer 2. A silicone varnish containing a methyl group is applied to a thickness of 2 μm on the surface of No. 2 to form an intermediate layer 3, and a silicone resin containing amorphous titania and amorphous silica is applied to the surface of the intermediate layer 3 Thus, a coating layer 4 was formed to obtain an outdoor sheet according to an example of the present invention.

As a comparative example, one obtained by directly forming the intermediate layer 3 and the paint layer 4 in the same manner as in the above embodiment without forming the primer layer 2 on the surface of the same sheet body 1 as in the above embodiment (comparative example) Example 1) The same sheet body 1 as in the above example was coated with a resin coating of an acrylic / fluorocopolymer to a thickness of 0.1 mm to form a top layer (Comparative Example 2). The same sheet body 1 was prepared by laminating a 50 μm-thick vinylidene fluoride / acrylic co-extruded film on the surface (Comparative Example 3).

Then, these Examples and Comparative Examples 1 to 3
JIS-L1023 to compare the antifouling properties of the sheets
The initial antifouling property, the antifouling property after 1000 hours irradiation with SWOM (Sunshine Weather Meter: Suga Test Machine), and the antifouling property after 30-degree outdoor exposure to the south side were visually evaluated. The result is shown in FIG.

As is apparent from the results shown in FIG.
The sheet according to the example of the present invention exhibited excellent antifouling properties in any of the items, and it was demonstrated that the sheet according to the comparative example had much better antifouling properties than the sheet of the comparative example according to the prior art.

[0028]

According to the present invention, a primer layer mainly composed of an ethyleneimine-modified polymer and an intermediate layer mainly composed of a silicone varnish are interposed between the sheet body and the silicone resin paint layer containing the photocatalyst particles. Therefore, an outdoor sheet which is excellent in weather resistance and antifouling property and does not cause delamination is provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of an outdoor seat according to an embodiment of the present invention.

FIG. 2 is a table showing the results of evaluating the antifouling properties of outdoor sheets according to Examples and Comparative Examples of the present invention.

[Description of Signs] 1 Sheet body 2 Primer layer 3 Intermediate layer 4 Photocatalytic particle-containing silicone resin paint layer

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Tadanori Iwabuchi 500 Kashima, Fukaya-shi, Saitama F-term in the Saitama Plant of Dynic Co., Ltd. F-term (reference) BA04 BA07 BA10A BA10C CA04 CA05 CA13 CC00B EH46 EJ65B GB01 GB90 JK06 JK13A JL06 JL08C JL09

Claims (3)

[Claims] The present invention is characterized in that a silicone resin paint layer containing photocatalyst particles is formed on the surface of a sheet body via a primer layer mainly composed of an ethyleneimine-modified polymer and an intermediate layer mainly composed of silicone varnish. And outdoor seats. 2. The outdoor sheet according to claim 1, wherein the sheet body is made of flexible PVC. 3. The outdoor sheet according to claim 1, wherein the photocatalyst particles are titania.