JP2000094610A - Surface protective sheet for high weather resistant shroud - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a surface protective sheet for a high weather resistant shroud of a polyolefin having little problem or an environmental pollution and a small change of an appearance for a long period by providing an ultraviolet absorption layer having a transmittance of an ultraviolet ray of a specific wavelength on one surface of a polyolefin resin film, and coating the other surface with a pressure sensitive adhesive. SOLUTION: An ultraviolet absorption layer having 5% or less of a transmittance of an ultraviolet ray of a wavelength of 300 to 360 nm is provided on one surface of a polyolefin resin film, and the other surface is coated with an adhesive layer. Thus, since no vinyl chloride is used, a problem of an environmental pollution is little, and an appearance change can be reduced for a long period. Since the polyolefin film is used, discarding after releasing is facilitated, and the problem of the pollution can be reduced. The appearance change can be reduced for a long period by a reducing effect caused by providing this absorption layer of the transmittance of the ultraviolet ray even when a polyolefin resin having a deteriorated weather resistance is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface protection sheet for a weatherproof shroud which is useful for outdoor display objects, in particular, for covering the outer wall of a shroud at construction and civil engineering work sites.

[0002]

2. Description of the Related Art Conventionally, in construction and civil engineering work sites, a shroud for isolating the work site from the external environment has been installed for the purpose of preserving the external environment. In recent years, an image of a construction site has been enhanced by attaching an adhesive sheet that can be peeled off, and that expresses patterns and characters to this shroud. However, as a base material of the pressure-sensitive adhesive sheet, a material having polyvinyl chloride as a support is often used, and there is a problem that it is not easy to dispose of the pressure-sensitive adhesive sheet peeled after completion of the construction.

In addition, polyolefin-based materials such as polyethylene and polypropylene, which have less problems of environmental pollution,
Poor weather resistance. Therefore, if the construction period is long,
There is a problem that the surface is significantly deteriorated and the appearance is impaired.

In order to solve such a problem, Japanese Utility Model Application Laid-Open No. 5-3502 describes a polyethylene terephthalate film containing an ultraviolet absorber.

[0005] The above technique is intended to incorporate an ultraviolet absorber into the film, and therefore cannot be applied to a film other than a polyethylene terephthalate film. Further, since the ultraviolet absorber is contained in the film, the surface layer portion is not sufficiently protected, and there is a problem that a minute crack or the like is generated. Furthermore, there is a problem that a step of separately containing an ultraviolet absorber is required at the time of film formation.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a polyolefin-based high weather resistance with less problems of environmental pollution and little change in appearance over a long period of time. An object of the present invention is to provide a surface protection sheet for an enclosure.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, the transmittance of ultraviolet light having a wavelength of 300 to 360 nm on one surface of a polyolefin resin film is 5% or less. By providing an ultraviolet absorbing layer and applying an adhesive to the other surface, a surface protection sheet for a polyolefin-based highly weather-resistant enclosing board having little problem of environmental pollution and little change in appearance over a long period of time can be obtained. It turned out that this invention was completed.

That is, the present invention is as follows. Wavelength 300 ~ on one side of polyolefin resin film
A surface protection sheet for a highly weather-resistant enclosing plate provided with an ultraviolet absorbing layer having a transmittance of 360% or less of ultraviolet rays of 5% or less, and coated with an adhesive on the other surface. 3. The surface protection sheet for a highly weather-resistant enclosure according to claim 1, wherein the ultraviolet absorbing layer contains an ultraviolet absorbing substance having an average particle size of 0.1 μm or less. The surface protection sheet for a highly weatherproof shroud according to the above, wherein the ultraviolet absorbing substance is zinc oxide. The surface protection sheet for a highly weather-resistant enclosing plate according to any one of-, wherein the ultraviolet absorbing layer is transparent. The surface protection sheet for a highly weather-resistant enclosure according to any one of claims 1 to 3, wherein the ultraviolet absorbing layer is provided on the outermost surface (outermost layer) of the surface protection material.

[0009]

According to the present invention, the above measures have been taken. If the surface protection sheet for a highly weather-resistant shroud of the present invention is used, since vinyl chloride is not used, there is little problem of environmental pollution and it can be used for a long time. Changes in appearance can be reduced. That is, the surface protection sheet for a highly weather-resistant enclosing plate of the present invention is provided with an ultraviolet ray preventing layer on one surface of a polyolefin film and an adhesive applied on the other surface. Since the polyolefin-based film is used, disposal after peeling is easy, and the problem of environmental pollution can be reduced. In addition, due to the effect of reducing the transmittance of ultraviolet light provided by providing the ultraviolet absorbing layer, the appearance change can be reduced over a long period of time even if a polyolefin resin having poor weather resistance is used.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The polyolefin resin film used in the present invention has a function as a substrate, and is not particularly limited as long as it can exhibit such a function. The polyolefin resin may be a homopolymer or a copolymer, or may be a mixture of two or more thereof. Specific examples include α-olefin homopolymers such as polyethylene and polypropylene, and ethylene-propylene copolymers.

The substrate may be colored by appropriately mixing a coloring agent such as a pigment or a dye. In addition, printing of pictures, characters, and the like may be performed. Further, another layer such as a printed layer may be provided on one side of the film.

As the ultraviolet absorbing substance used in the present invention, any substance can be used as long as it can reduce the transmittance of ultraviolet rays, but preferably, it can maintain transparency.
Specific examples of such an ultraviolet absorbing material include zinc oxide. Further, the ultraviolet absorbing layer used in the present invention is desirably transparent. If the ultraviolet absorbing layer is transparent, for example, even if a pattern is applied to the polyolefin resin film or the like by printing or the like, it is not concealed and does not impair the appearance. Therefore,
Here, the term “transparent” refers to a degree of transparency such that a pattern applied to the polyolefin-based resin film can be seen through the ultraviolet absorbing layer.

When zinc oxide is used as the ultraviolet absorbing material, the average particle size of zinc oxide is preferably 0.1 μm or less. If the average particle size of zinc oxide exceeds 0.1 μm, the transparency is inferior and the appearance of the base is impaired.
Further, the refractive index is desirably about 1.9 to 2.0. If the refractive index is about 1.9 to 2.0, the transmittance of ultraviolet rays can be effectively reduced and the transparency can be maintained.

The thickness of the ultraviolet absorbing layer can be appropriately selected as long as the transmittance of ultraviolet rays can be effectively reduced and the transparency can be maintained. Preferably it is about 0.1 to 1 μm.

The ultraviolet absorbing layer may be provided on one side of the polyolefin resin film. When another layer is laminated on the polyolefin resin film, the ultraviolet absorbing layer is desirably provided on the rearmost surface (outermost layer) of the polyolefin resin film. By providing the rearmost (outermost) layer, the transmittance of ultraviolet rays can be effectively reduced, and a high degree of weather resistance can be imparted to the polyolefin resin film.

The pressure-sensitive adhesive used in the present invention is not particularly limited as long as the object of the present invention can be achieved. For example, known pressure-sensitive adhesives can be used. Adhesives, silicone adhesives and the like can be used alone or in combination of two or more.

In the pressure-sensitive adhesive layer of the present invention, known additives such as a cross-linking agent, a coloring agent, a plasticizer, a filler, a tackifier, an antioxidant, and the like are added, if necessary, in addition to the above components. You may.

The surface protection sheet for a highly weather-resistant enclosure according to the present invention is attached to the surface of an enclosure such as a steel plate. Then, an enclosing plate to which the surface protection sheet for a highly weather-resistant enclosing plate is stuck is constructed in the same manner as a conventional enclosing plate to perform construction. Since the enclosing plate to which the protective sheet is attached is provided with the ultraviolet absorbing layer, it is rich in weather resistance even if the construction period is long.

Further, since the surface protection sheet for a highly weather-resistant shroud of the present invention uses a polyolefin resin as a base material, it is easy to dispose of the protection sheet peeled off after the completion of construction, and it is possible to reduce environmental pollution. There are few problems.

[0020]

The present invention will be described below with reference to examples.
The present invention is not limited to these.

In the present invention, the transmittance of ultraviolet rays was measured by using a spectrophotometer (MPS-2000, manufactured by Shimadzu Corporation) to measure the transmittance of ultraviolet rays having a wavelength of 290 to 380 nm.

The measurement of the average particle size was performed as follows.
Laser diffraction particle size distribution analyzer (manufactured by Horiba, Ltd.)
Was used to disperse zinc oxide in water, and the average particle size was measured. The average particle size was determined by the following equation. Average particle size = Σ (q (J) × χ (J)) / Σ (q (J)) where J: particle size division number (1 to 80 at fixed intervals) q (J); frequency distribution value ( %) Χ (J); representative diameter of the J-th particle diameter range (μm)

Example 1 Zinc oxide (average particle size: 0.04 μm) was applied to a thickness of 1 μm on a polyethylene film having a thickness of 60 μm to form an ultraviolet absorbing layer. On the surface opposite to the ultraviolet absorbing layer, polyisobutylene (Exxon Chemical Co., Ltd.) was used. Co., Ltd., trade name Vistanex MML
-100) as a pressure-sensitive adhesive layer by applying 15 μm to prepare a surface protection sheet for a highly weather-resistant enclosure of the present invention. Regarding the protective sheet, a wavelength of 300 to
The transmittance of 360 nm ultraviolet rays was 4.5%.

Example 2 A 60 μm thick polypropylene film was coated with 0.5 μm thick zinc oxide (average particle size 0.02 μm) to form an ultraviolet absorbing layer. On the surface opposite to the ultraviolet absorbing layer, butyl acrylate / An acrylic pressure-sensitive adhesive obtained by adding 3 parts by weight of hexamethylene isocyanate to 100 parts by weight of an acrylic polymer of acrylic acid = 98/2 (weight ratio) has a thickness of 1 after drying.
The resultant was coated and dried so as to have a thickness of 0 μm to prepare a surface protection sheet for a highly weather-resistant enclosure of the present invention. With respect to the protective sheet, the transmittance of the ultraviolet absorbing layer with respect to ultraviolet light having a wavelength of 300 to 360 nm was 1.0%.

Comparative Example 1 The procedure of Example 1 was repeated except that no ultraviolet absorbing layer was provided.

EXPERIMENTAL EXAMPLE 1 The surface protective sheet for an enclosure obtained in Examples 1 and 2 and Comparative Example 1 was tested. The surface protective sheet for an enclosure obtained in Examples 1 and 2 and Comparative Example 1 was adhered to the enclosure, exposed to the outdoors, allowed to stand for one year, and then visually observed for surface deterioration.

In Comparative Example 1, the surface was significantly deteriorated, but in Examples, no surface deterioration was observed.

[0028]

As is clear from the above description, since the surface protection sheet for a highly weather-resistant enclosing plate of the present invention uses a polyolefin-based film, it is easy to dispose after peeling off, and to reduce environmental pollution. Problems can be reduced. In addition, since the ultraviolet absorbing layer is formed of an ultraviolet absorbing material that can reduce the transmittance of ultraviolet light, it imparts high weather resistance to a polyolefin film having poor weather resistance, and can reduce the appearance change over a long period of time.

 ────────────────────────────────────────────────── ─── Continued on the front page F term (reference) 4F100 AA25B AK03A AK04A AK09C AR00B AR00C BA03 BA07 BA10B BA10C CA07B DE01B GB90 JD09B JD14B JL09 JL13C JN01B 4J004 AA10 AB01 CA04 CA07 CC02 CD01 FA04

Claims (5)

[Claims] 1. A surface protection for a highly weather-resistant enclosing plate in which an ultraviolet absorbing layer having a transmittance of ultraviolet rays having a wavelength of 300 to 360 nm of 5% or less is provided on one surface of a polyolefin resin film and an adhesive is applied on the other surface. Sheet. 2. The method according to claim 1, wherein the ultraviolet absorbing layer has an average particle size of 0.1 μm.
The surface protection sheet for a highly weather-resistant enclosure according to claim 1, wherein the surface protection sheet contains an ultraviolet absorbing material of m or less. 3. The surface protection sheet according to claim 2, wherein the ultraviolet absorbing material is zinc oxide. 4. The surface protection sheet for a highly weather-resistant enclosure according to claim 1, wherein the ultraviolet absorbing layer is transparent. 5. The surface protection sheet for a highly weather-resistant enclosure according to claim 1, wherein the ultraviolet absorbing layer is provided on the outermost surface (outermost layer) of the surface protective material.