JP2009096107A - Decorative sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a decorative sheet capable of suppressing bleedout of a low-molecular weight component in the lapse of time as building exterior application and capable of maintaining inter-layer adhesion, design and weather resistance. <P>SOLUTION: The decorative sheet comprises at least two layers of olefin based resin layers 12, wherein the olefin based resin layers 12 contain organic ultraviolet ray absorbers having different ultraviolet ray absorbing wavelengths, preferably in the two layers of olefin based resin layers, as the olefin based resin first layer 1 of the surface layer side, a block polypropylene resin or a homo polypropylene resin having crystal component isotactic pentad fraction 95% or more is used, as the olefin based resin second layer 2 of the lower layer side, a soft polypropylene resin having a tensile modulus specified according to JIS Z 1702 of 30 to 800 MPa is used and, for either layer, a triazine type ultraviolet absorber and a benzotriazole type ultraviolet absorber are jointly added. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a decorative sheet used for building exterior and building interior, for building materials such as surfaces and frame materials for building fixtures, surface materials for household electrical appliances, and flooring materials, and more particularly wooden boards and inorganic materials. The present invention relates to a decorative sheet that is used as a decorative plate by being bonded to the surface of a board, a metal plate or the like with an adhesive.

  As a decorative sheet used for the decorative plate, a decorative sheet using a resin and a copolymer such as polyethylene, polypropylene, polyethylene terephthalate, ethylene vinyl alcohol, and acrylic has been proposed and is commercially available.

  Among them, polypropylene, etc. due to the moderate flexibility required for decorative sheets, abrasion resistance, scratch resistance, heat resistance, chemical resistance, post-processability such as bending after bonding to wooden boards and steel plates, etc. A decorative sheet provided with an olefin-based resin layer is known (see, for example, Patent Document 1).

  In addition, for the purpose of protecting the design printed on the base material sheet for cosmetics and preventing the deterioration of the olefinic resin layer itself, the olefinic resin layer has an ultraviolet absorber, a light stabilizer, etc. The weathering agent is added.

  As the ultraviolet absorber, benzophenone series, benzotriazole series, and triazine series are generally used and have a molecular weight of about 200 to 400. A hindered amine light stabilizer having a high molecular weight is generally used.

  In the olefin-based resin layer, when soft polyolefin is used to give post-processing suitability, or when a weathering agent is added at a high concentration in order to obtain high weather resistance, a low molecular weight component during polymerization or a molecular weight of less than 1000 There is a problem that the ultraviolet absorber bleeds out with time, which may lead to adverse effects on quality, such as inhibiting interlaminar adhesion of each layer, damaging a printed pattern or design, and not obtaining the required weather resistance.

  In general, the bleed-out phenomenon is such that when a low molecular weight component having a molecular weight of less than 1000 does not have a physical connection between molecules, the bleed out phenomenon tends to move in an amorphous region, and external factors such as temperature and added resin It is said that it is a problem of exudation on the surface due to the compatibility of.

If polyolefin with high crystallinity is used in order to suppress bleed-out, the post-processing suitability may be hindered, and it is necessary to devise the selection of the olefin resin and the weathering agent prescription.
JP 2001-38863 A

  The problems to be solved by the present invention with respect to the problems as described above are, in a decorative sheet having an olefin resin layer, suppressing the bleed out of low molecular weight components having a molecular weight of less than 1000 over time, and interlayer adhesion. It is providing the decorative sheet which can maintain property, design property, and weather resistance quality.

  The invention according to claim 1 is a decorative sheet comprising at least two olefinic resin layers, wherein the olefinic resin layer contains organic ultraviolet absorbers having different ultraviolet absorption wavelengths. It is a decorative sheet.

  The invention according to claim 2 is defined by JIS Z 1702 in which the first olefin-based resin layer on the surface layer side is a block polypropylene resin and the lower olefin-based resin second layer is the olefin-based resin layer. The makeup according to claim 1, wherein a soft polypropylene resin having a tensile elastic modulus of 30 to 800 MPa is used, and a triazine-based UV absorber and a benzotriazole-based UV absorber are used in combination with any layer. It is a sheet.

  The invention according to claim 3 is a homopolypropylene resin having a crystal component isotactic pentad fraction of 95% or more as the first olefin resin layer on the surface layer side of the two olefin resin layers, The second layer of the olefin resin is a soft polypropylene resin having an elastic modulus of 30 to 800 MPa defined by JIS Z 1702, and a triazine UV absorber and a benzotriazole UV absorber are added to both layers in combination. The decorative sheet according to claim 1.

  The invention according to claim 4 is the decorative sheet according to any one of claims 1 to 3, wherein the two olefin-based resin layers are bonded to a base sheet via an adhesive resin layer.

ADVANTAGE OF THE INVENTION According to this invention, the decorative sheet which suppresses the bleed-out of the low molecular weight component with a molecular weight of less than 1000 with time, and can maintain interlayer adhesiveness, design property, and weather resistance quality can be provided.
In particular, among at least two olefin resin layers, the first olefin resin layer on the surface layer side is a block polypropylene resin or a homopolypropylene resin having a crystal component isotactic pentad fraction of 95% or more, and the lower olefin By adding a triazine-based UV absorber and a benzotriazole-based UV absorber to both layers as a soft polypropylene resin having an elastic modulus of 30 to 800 MPa specified by JIS Z 1702 In addition, the suppression of bleed-out of low molecular weight components over time, interlayer adhesion, design properties, and weather resistance of each layer can be maintained over a long period of time.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing a cross-sectional structure of one embodiment of the decorative sheet of the present invention. On the base material sheet (6), an ink layer (5), an adhesive layer (32), and an olefin resin layer (12) are laminated in this order. The olefin-based resin layer (12) is composed of a first olefin-based resin layer (1) that forms a surface layer and a second olefin-based resin layer (2) below it, and is transparent or translucent. As shown in FIG. 1, the adhesive layer (32) may have a two-layer structure of an adhesive resin layer (3) and an adhesive layer (4).

  The olefin-based resin layer in the present invention is mainly used for the protection of the decorative sheet pattern, the improvement of the design and the chemical resistance, and the maintenance of the functionality of the decorative sheet. Polypropylene is preferably used as the resin layer, and heat stabilizers, flame retardants, UV absorbers, light stabilizers, antiblocking agents, catalyst supplements, nucleating agents, etc. are appropriately added as necessary. May be.

  Among them, it is necessary to add an ultraviolet absorber in order to prevent ultraviolet degradation of the olefin resin itself.

  In addition, as the ultraviolet absorber, use of a benzotriazole type which is excellent in absorption at around 370 nm in the ultraviolet region and a combination of triazine type which is excellent in absorption at around 300 nm are preferable. Moreover, by using together, each addition density | concentration can also be suppressed and it leads to suppression of the time bleed-out of the ultraviolet absorber which is molecular weight less than 1000.

  In a preferred form (part 1) of the present invention, the olefin resin first layer (1) is preferably a block polypropylene resin. Preferably, the block polypropylene resin is characterized by a sea-island structure composed of a crystalline polymer sea (matrix) and an amorphous polymer island (dispersed phase) such as EPR. When a low molecular weight ultraviolet absorber is added to the block polypropylene resin, the movement in the crystal region becomes slow and tends to stay between the sea and the island, so that bleed out can be suppressed.

  If the olefin resin layer is made into a soft polypropylene resin single layer, the bleed-out of the first layer of the olefin resin is difficult because the bleedout of the UV absorber having a low molecular weight of less than 1000 is remarkable over time. Use polypropylene resin.

  In decorative sheets, post-processing such as bending and squeezing is performed after bonding to a wooden substrate or steel plate. Whitening due to the deviation of EPR occurs, and there is no denying the problem that the design as a decorative sheet is impaired.

Therefore, in the preferred embodiment (No. 1) of the present invention, in order to maintain the post-processing suitability of the decorative sheet, JIS Z 1702 is applied as the olefin resin layer to the second olefin resin layer (2) below the block polypropylene resin. The problem can be solved by providing a layer of a soft polypropylene resin having a tensile modulus of elasticity of 30 to 800 MPa as defined by the above, and by setting the layer ratio (thickness) of block polypropylene to soft polypropylene to about 1: 9 to 2: 8. Can be avoided.
When the tensile elastic modulus is less than 30 MPa, scratch resistance is impaired, and when it exceeds 800 MPa, whitening occurs at the time of bending or graining, which is not preferable. A more preferable tensile elastic modulus is 100 to 700 MPa.

  Further, another preferred embodiment of the present invention (part 2) is characterized in that the first olefin resin layer (1) is a homopolypropylene resin having a crystal component isotactic pentad fraction of 95% or more. For the purpose of suppressing bleed out of the added low molecular weight component having a molecular weight of less than 1000, the amorphous region of the homopolypropylene resin is reduced, and the movement of the low molecular weight component becomes dull. .

  In the above-mentioned another preferred embodiment (part 2), the olefin-based resin cannot be satisfied with the post-processing suitability of the decorative sheet as described above only by making the first layer of the olefin-based resin (1) as a single layer. As the olefin resin second layer (2) as the lower layer of the first layer, soft polypropylene having a tensile modulus of elasticity of 30 to 800 MPa defined by JIS Z 1702 is used, and the layer ratio (thickness) of homopolypropylene and soft polypropylene is 1: Set to about 9 to 2: 8.

  When the first layer of the olefin resin (1) is a block polypropylene resin of the preferred form of the present invention (part 1), it has a sea-island structure consisting of a sea of crystalline polymer and an island of amorphous polymer such as EPR. Since low molecular weight components having a molecular weight of 1000 or less tend to stay in the crystalline region and tend to stay between the sea and the island, bleed out can be expected to be suppressed. Compared with the use of the homopolypropylene resin of 2), the addition of a high concentration of the UV absorber to be added can be expected.

When a decorative sheet is bonded to a wooden substrate or a steel plate and post-processing such as bending is performed, in the case of acute bending, the block polypropylene resin is feared to be whitened due to the difference between the matrix and the dispersed phase due to the sea-island structure, In the case where the post-processing is a severe condition, it is desirable to use a homopolypropylene resin of another preferred form (part 2) of the present invention.
Depending on the required quality of the decorative sheet, it is selected whether the olefin-based resin first layer (1) is to be the preferred form of the present invention (part 1) or another preferred form of the present invention (part 2). It is desirable.

  In any of the above preferred embodiments of the present invention, it is desirable to add an ultraviolet absorber to the olefin resin second layer (2). In this case, in the prior art, it is assumed that the bleed out with time. However, according to the present invention, it is possible to prevent bleeding out to the surface as described above.

  As for the ultraviolet absorber used by this invention, it is desirable to add together a triazine type ultraviolet absorber and a benzotriazole type ultraviolet absorber.

  The triazine-based ultraviolet absorber added to the olefin-based resin layer (12) in the present invention is 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5-[(hexyl) oxy. ] -Phenol, 2- [4-[(2-hydroxy-3-dodecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5- Triazine, 2- [4-[(2-hydroxy-3-tridecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4dimethylphenyl) -1,3,5-triazine, 2,4-bis (2,4-dimethylphenyl) -6- (2-hydroxy-4-iso-octyloxyphenyl) -s-triazine and the like, mixtures, modified products, polymers and derivatives thereof. It is below. One or more of these may be selected and used.

  In the case of a block polypropylene resin, the addition amount is preferably 0.1 to 5 parts by weight with respect to 100 parts by weight. In the case of a homopolypropylene resin, the content is preferably 0.1 to 3 parts by weight with respect to 100 parts by weight. In the case of a soft polypropylene resin, the content is preferably 0.1 to 2 parts by weight with respect to 100 parts by weight.

  Examples of the benzotriazole ultraviolet absorber added to the olefin resin layer (12) in the present invention include 2- (2H-benzotriazol-2-yl) -p-cresol and 2- (2H-benzotriazol-2-yl). ) -4-6-bis (1-methyl-1-phenylethyl) phenol, 2- [5-chloro (2H) -benzotriazol-2-yl] -4-methyl-6- (tert-butyl) phenol, 2- (2H-benzotriazol-yl) -4,6-di-tert-pentylphenol, 2- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) Examples thereof include phenol and the like, mixtures thereof, modified products, polymers, and derivatives. One or more of these may be selected and used.

  In the case of a block polypropylene resin, the addition amount is preferably 0.1 to 3 parts by weight with respect to 100 parts by weight. In the case of a homopolypropylene resin, the content is preferably 0.1 to 1 part by weight with respect to 100 parts by weight. In the case of a soft polypropylene resin, it is good to set it as 0.1-1 weight part with respect to 100 weight part.

  In addition to the triazine-based and benzotriazole-based UV absorbers, examples of the weathering agent added to the olefin-based resin layer (12) include light stabilizers, and hindered amine light stabilizers are preferable.

  Examples of the hindered amine light stabilizer used in the olefin resin layer (12) include dimethyl succinate, 1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine, poly [{ 6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexa Methylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}], N, N′-bis (3-aminopropyl) ethylenediamine · 2,4-bis [N-butyl-N- (1 , 2,2,6,6-pentamethyl-4piperidyl) amino] -6-chloro-1,3,5-triazine, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, 2- (3,5-di -T-butyl-4-hydroxybenzyl) -2-n-butylmalonate bis (1,2,2,6,6-pentamethyl-4-piperidyl), tetrakis (1,2,2,6,6-pentamethyl) -4-piperidyl) 1,2,3,4-butanetetracarboxylate and the like can be exemplified, and these can be used alone or in combination.

  In addition to the ultraviolet absorber and the light stabilizer, the olefin-based resin layer (12) has a heat stabilizer, a flame retardant, an antiblocking agent, a catalyst accelerator, and a transparency maintained as necessary. Colorants, light scattering agents for translucency, gloss adjusting agents, and the like can be added.

  The lamination method with respect to the base material sheet (6) enables lamination by dry lamination or lamination by extrusion lamination. In the case of dry lamination, the olefin resin layer needs to be formed into a sheet in advance before bonding, whereas in the case of extrusion lamination, both the olefin resin first layer and the second layer are used. By co-extrusion molding, it becomes possible to bond with a base material sheet in-line.

  Moreover, according to the bonding method, you may use an adhesive bond layer, a primer coat layer, etc. in the bonding interface of a base material sheet and an olefin resin layer.

  A surface protective layer may be provided on the surface side of the olefin resin first layer in order to provide contamination resistance, scratch resistance, chemical resistance, and the like. In the case of providing a surface protective layer, it is desirable to add a weathering agent to the layer to provide the weather resistance of the layer itself.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not restrict | limited to the following example.

Example 1
The olefin resin first layer was made of block polypropylene in which ethylene, propylene and rubber were dispersed, and the olefin resin second layer was made of soft polypropylene having a tensile elastic modulus of 500 MPa.

  Triazine-based ultraviolet absorber (2- (4,6-diphenyl-1,3,5-triazin-2-yl)-, based on 100 parts by weight of the first and second layers of the olefin-based resin layer, respectively. 5-[(hexyl) oxy] -phenol), hindered amine light stabilizer (poly [{6- (1,1,3,3-tetramethylbutyl) amino-1,3, 5-triazine-2,4diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}] ) 0.5 parts by weight, phenolic antioxidant (Irganox 1010: manufactured by Ciba Specialty Chemicals Co., Ltd.), 0.5 parts by weight, benzotriazole-based UV absorber (2- (2H-benzotriazole-2) − ) -4-6-bis (1-methyl-1-phenylethyl) phenol), hindered amine light stabilizer (poly [{6- (1,1,3,3-tetra Methylbutyl) amino-1,3,5-triazine-2,4diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetra 0.5 parts by weight of methyl-4-piperidyl) imino}]) and 0.5 parts by weight of a phenolic antioxidant (Irganox 1010: manufactured by Ciba Specialty Chemicals) were added.

  Further, a transparent polyethylene base sheet (120 μm) having a thickness of about 80 μm, on which a wood grain pattern was printed and a two-component curable urethane resin system was applied as an adhesive layer, was prepared.

  The acid-modified polypropylene adhesive resin, the olefin resin second layer, and the olefin resin first layer are melt extruded by co-extrusion with a T-die extruder at a thickness of 10 μm, 70 μm, and 10 μm. The decorative sheet according to the present invention was prepared by pasting on the material sheet.

Example 2
The first olefin resin layer was a homopolypropylene having a pentad fraction of 98%, and the second olefin resin layer was a soft polypropylene having a tensile elastic modulus of 500 MPa.

The first and second layers of the olefin-based resin layer are each 0.5 parts by weight of triazine-based UV absorber, 0.5 part by weight of benzotriazole-based UV absorber, and hindered amine for 100 parts by weight. 0.5 part by weight of the system light stabilizer was added.
About the others, the decorative sheet which concerns on this invention was created using the material and manufacturing method similar to Example 1. FIG.

(Comparative Example 1)
The olefin-based resin layer is composed of only soft polypropylene, and 100 parts by weight of triazine-based UV absorber, 0.5 part by weight of benzotriazole UV absorber, and 0.5 part by weight of hindered amine light stabilizer. The added resin was used.
About the other, the decorative sheet containing 80 micrometer of olefin resin layer thickness was created using the material and manufacturing method similar to Example 1. FIG.

(Comparative Example 2)
The olefin-based resin layer was made of only soft polypropylene, and a resin in which 1.0 part by weight of a benzotriazole ultraviolet absorber and 0.5 part by weight of a hindered amine light stabilizer were added to 100 parts by weight.
About the other, the decorative sheet containing 80 micrometer of olefin resin layer thickness was created using the material and manufacturing method similar to Example 1. FIG.

(Comparative Example 3)
As the olefin resin layer, a soft polypropylene was used, and a resin in which 1.0 part by weight of a triazine UV absorber and 0.5 part by weight of a hindered amine light stabilizer were added to 100 parts by weight.
About the other, the decorative sheet containing 80 micrometer of olefin resin layer thickness was created using the material and manufacturing method similar to Example 1. FIG.

<Performance comparison>
The decorative sheet of Example 1, Example 2 and Comparative Example 1, Comparative Example 2, and Comparative Example 3 produced as described above was subjected to the following comparative evaluation, and the results are shown in Table 1.

(Comparative test 1)
Regarding the influence on the printed pattern due to bleed-out, the sample was allowed to stand in an environment of 40 ° C. and 90% relative humidity for 96 hours. Evaluation was performed using a spectrocolorimeter (CM-508D manufactured by Konica Minolta, Inc.).

(Comparative test 2)
In order to evaluate the weather resistance of the sample, a weather resistance acceleration test (metal halide lamp type tester JTM G 01 2000 Japan Testing Machine Industry Association Standard) was conducted. As a tester, a die plastic metal weather (KU-R5CI-A: manufactured by Daipura Wintes Co., Ltd.) was used.

The weathering accelerated test conditions are
1. Light source lamp: MW-60W, filter: KF-1 (irradiation range 295 nm to 780 nm) illuminance 65 ± 3 mW / cm ² (measurement range 330 nm to 390 nm) Light (irradiation) (53 ° C., 50% RH) 20.00 hours 2 . 2. Dew (dark condensation) (30 ° C., 98% RH) 4.00 hours Rest (rest) (30 ° C, 98% RH) 0.01 hours
The above 24.01 hours was defined as one cycle, and the test was performed for 216 hours. The shower was performed for 30 seconds before and after Dew.

  For the decorative sheets of Example 1, Example 2, Comparative Example 1, Comparative Example 2 and Comparative Example 3 subjected to the weathering acceleration test, the olefin resin layer was forcibly peeled off using a peeling solvent, and the peeled olefin was removed. The transmittance of ultraviolet rays at 360 nm and 300 nm of the system resin layer was measured. The results are shown in Table 1.

  From the above results, the decorative sheet according to the present invention has suppressed bleeding out to the surface of the olefin-based resin layer as compared with the conventional decorative sheet, and the ability of the ultraviolet absorber after the weather resistance test is reduced. Could be suppressed.

It is explanatory sectional drawing of an example of the decorative sheet of this invention.

Explanation of symbols

(1) Olefin resin first layer (2) Olefin resin second layer (12) Olefin resin layer (3) Adhesive resin layer (4) Adhesive layer (32) Adhesive layer ( 5) ... Ink layer (6) ... Base sheet

Claims (4)

  A decorative sheet comprising at least two olefin resin layers, wherein the olefin resin layer contains organic ultraviolet absorbers having different ultraviolet absorption wavelengths.   Of the two olefin-based resin layers, the first olefin-based resin layer on the surface layer side is a block polypropylene resin, and the lower olefin-based resin second layer is a soft material having a tensile modulus of 30 to 800 MPa defined by JIS Z 1702. 2. The decorative sheet according to claim 1, wherein a polypropylene resin is used, and a triazine-based UV absorber and a benzotriazole-based UV absorber are added in combination to any layer.   Of the two olefin resin layers, the first olefin resin layer on the surface layer side is a homopolypropylene resin having a crystal component isotactic pentad fraction of 95% or more, and the lower olefin resin resin second layer is JIS Z. A soft polypropylene resin having an elastic modulus of 30 to 800 MPa defined by 1702 and a triazine-based UV absorber and a benzotriazole-based UV absorber are added in combination to any layer. The decorative sheet as described.   The decorative sheet according to any one of claims 1 to 3, wherein the two olefin-based resin layers are bonded to a base sheet via an adhesive resin layer.

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