JP4161698B2 - Decorative sheet - Google Patents

Description

【００８６】
【表２】

【００８７】
【発明の効果】
以上説明したように、本発明の化粧シートは、塩化ビニルを一切使用しないため環境問題の心配もなく、且つ金属化粧板加工時の高温貼り付けに対する耐熱性を有し、優れた耐候性を有し且つ、低温での曲げ白化を起こさない化粧シートを提供できる効果がある。
【図面の簡単な説明】
【図１】本発明による化粧シートの一例を示す側断面図。
【符号の説明】
１…基材シート
２…模様層
３…アンカーコート層
４…接着性樹脂層
５…ポリプロピレン樹脂層
５ａ…凹陥模様
６…トップコート層[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a decorative sheet, and more particularly to a decorative sheet for metal plates and a decorative material made of a non-chlorine resin.
[0002]
[Prior art]
In the case of metal decorative boards, there are coated steel sheets that maintain the design by resin coating on the metal surface, but since high design and embossed expression cannot be obtained by painting, PVC decorative sheets are used. It has been used as a decorative sheet for metal plates.
[0003]
However, demands for decorative sheets other than vinyl chloride have increased due to environmental problems caused by vinyl chloride in recent years, particularly concerns regarding the generation of chlorine and dioxins during combustion.
[0004]
Under such circumstances, a decorative sheet using an acrylic resin, a decorative sheet using a completely non-crystalline polyester resin, and the like have appeared.
[0005]
However, these vinyl chloride substitute decorative sheets use expensive resins as compared with vinyl chloride resins, and are not perfect substitutes.
[0006]
In addition, there is an example of using an inexpensive polyolefin-based resin decorative sheet, but there are problems such as whitening and cracking at the time of bending, and the usable parts are limited.
[0007]
Among them, many decorative sheets using polypropylene having appropriate flexibility, abrasion resistance, scratch resistance, heat resistance, chemical resistance, post-processability and the like required for the decorative sheet have been proposed.
[0008]
In particular, a decorative sheet using polypropylene characterized by having a whitening elongation of 150% or more and a breaking elongation of 150% or more has bending whitening resistance capable of withstanding bending of a metal plate.
[0009]
Polypropylene resin is a resin having poor adhesion to the same or different types of resins. Therefore, when a polypropylene resin layer is melt-extruded and laminated to another resin layer, for example, maleic acid-modified polyethylene resin or ethylene- (meta) In general, extrusion lamination is performed through an adhesive resin layer such as an acrylic acid copolymer.
[0010]
However, these decorative sheets extruded and laminated through an adhesive resin layer such as maleic acid-modified polyethylene resin or ethylene- (meth) acrylic acid copolymer have a laminate strength when the surface temperature and the atmospheric temperature are 90 ° C. or higher. Will drop significantly.
[0011]
Usually, many adhesives used for bonding a decorative sheet to a metal plate are subjected to a high-temperature treatment, and the decorative sheet is bonded to a metal plate heated to about 200 ° C. to 220 ° C. and cooled and fixed.
[0012]
Therefore, the sheet is given a high temperature of 100 ° C. or higher for several seconds.
[0013]
Because of the processing as described above, the decorative sheet extruded and laminated through an adhesive resin layer such as maleic acid-modified polyethylene resin or ethylene- (meth) acrylic acid copolymer is easily attached to the metal plate. It will peel off.
[0014]
[Patent Document 1]
Japanese Patent Laid-Open No. 2001-353828
In addition, Patent Document 1 has already proposed a decorative sheet having a configuration in which a polypropylene-based adhesive resin is used for the adhesive resin layer in order to impart heat resistance.
[0016]
However, the peel strength after bonding the metal plates did not decrease, but the components such as rubber and polyethylene added inside caused the interface peeling inside the adhesive resin due to the heat at the time of bonding, and the metal plate was bent At this time, cracks are easily generated at the interface and whitening occurs at the bent portion.
[0017]
[Problems to be solved by the invention]
The present invention has been made in order to solve the above-mentioned problems, and the object of the present invention is to use a material other than vinyl chloride resin and to be heat-resistant and bent so that it can be bonded to a metal decorative plate. An object of the present invention is to provide a decorative sheet having bending workability that sometimes does not cause whitening.
[0018]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the invention according to claim 1 of the present invention is to apply a urethane anchor coating agent to the surface of a base sheet made of paper, olefin resin, acrylic resin, polyester resin or polyvinyl alcohol resin. ,
A polypropylene resin layer comprising homopolypropylene with an isotactic index of 90; and
A modified random polypropylene resin graft-polymerized with maleic anhydride (a carbonyl group content in 1 g of modified random polypropylene is 0.02 mmol equivalent), and an adhesive resin layer containing a resin in which 20% of hydrogenated styrene butadiene rubber is added.
In the coextruded decorative sheet, the main component of the urethane anchor coat agent is an isocyanate curable resin made of a mixture of polyester polyol and urethane-modified polyester polyol .
[0019]
Next, when the main component contained in the urethane anchor coating agent is considered to be 100% by weight, the main component is composed of a mixture of 20 to 80% by weight of polyester polyol and 80 to 20% by weight of urethane-modified polyester polyol. The decorative sheet according to claim 1, wherein the decorative sheet is a decorative sheet.
[0020]
[Means for Solving the Problems]
Next, the isocyanate component is composed of a mixture of 30 to 98% by weight of isophorone diisocyanate and 2 to 70% by weight of other isocyanate components when the total isocyanate component contained in the urethane anchor coating agent is considered to be 100% by weight. The decorative sheet according to claim 1 or 2, wherein the decorative sheet is provided.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a cross-sectional view of a decorative sheet according to the present invention.
[0022]
As shown in FIG. 1, the basic structure of a typical decorative sheet of the present invention is a pattern layer 2, an anchor coat layer 3, an adhesive resin layer 4, a polypropylene resin layer 5, and a top coat layer 6 on a base sheet 1. Are stacked in order, and the pattern layer 2 is patterned therein, and a concave pattern 5 a is provided from the surface to the middle of the polypropylene resin layer 5.
[0023]
Next, the material of the base sheet 1 is made of paper, olefin resin, acrylic resin, polyester resin, or polyvinyl alcohol resin. This is because the property of not containing chlorine in the material is a requirement. In addition, you may consist of these mixtures and laminated bodies. However, as described later, a colorant, a masking agent, and other antistatic agents may be contained in a small amount. The thickness of the base sheet 1 is preferably between 50 and 200 μm. If it is too thick, it will be difficult to paste or bend, and if it is too thin, it will pick up the paste, and there will be insufficient concealment.
[0024]
The pattern layer 2 on this is unnecessary when it is plain, but is generally provided. The pattern layer 2 is generally printed by a known printing method such as gravure, intaglio, letterpress or silk screen printing, but is not necessarily limited thereto.
[0025]
Also, the ink used is a known one, that is, a colorant such as a dye or pigment or an extender pigment is added to the vehicle, and further a plasticizer, stabilizer, wax, grease, desiccant, curing agent, thickener, dispersant. Ink obtained by arbitrarily adding a filler or the like and sufficiently kneading with a solvent, a diluent or the like may be used. The thickness of the pattern layer 2 is preferably 5 μm or less. This is because if the thickness is too large, the smoothness of other layers is affected.
[0026]
Further, the concealing layer and / or the pattern layer 2 is formed on an arbitrary transfer base sheet different from the base sheet 1 for the decorative sheet by the above-described forming method and the like. After laminating, laminating, dry laminating, wet laminating, extrusion laminating, and the like, the substrate sheet for transfer is peeled off, and then the concealing layer and / or the pattern layer 2 or both. It is also possible to use a method of transferring the material to the substrate sheet 1.
[0027]
Further, when the T-die extrusion method is used as the method for producing the base sheet 1, the synthetic resin material for forming the base sheet 1 is directly colored with a concealing colorant such as a dye or pigment. By extruding from a T-die in a heated and melted state to form the base sheet 1, it is possible to have a concealing effect.
[0028]
As a coloring method of the base sheet 1 in the T-die extrusion method in this case, a fine powdery colorant obtained by treating a pigment with a dispersion aid or a surfactant is colored to form the base sheet 1. A dry color method used by directly mixing in an ordinary synthetic resin material that is not used, or an uncolored ordinary synthetic resin material and a high-concentration pigment for forming the base sheet 1 are melt-kneaded. A master batch method in which pre-dispersed master batch pellets are prepared in advance, and the master batch pellets are dry blended with an ordinary uncolored synthetic resin material for forming the base sheet 1 in an extrusion hopper. However, it is not particularly limited.
[0029]
The types of pigments may be those usually used, but inorganic pigments such as titanium oxide, ultramarine blue, cadmium pigment, iron oxide and the like are particularly desirable in consideration of heat resistance and weather resistance.
[0030]
Also, organic pigments such as phthalocyanine pigments and quinacridone pigments can be used.
[0031]
The ratio of the pigment to the resin and the color are appropriately determined in view of the degree of concealment and design properties, and are not particularly limited.
[0032]
The method of applying the pattern layer 2 to the base sheet 1 includes the method of applying to the surface of the base sheet 1 and the method of applying to the base sheet 1 itself (in the layer of the sheet 1). As a method for applying to the base sheet 1 itself, a high-concentration pigment is melt-kneaded into a resin having different flow characteristics from the resin of the base sheet 1 and preliminarily dispersed. The master batch pellets or wood powder, glass powder, etc., added to the synthetic resin material provided with the concealability for forming the base sheet 1 is melted by heating, extruded, formed into a film and concealed. There is also a method of forming a pattern with a master batch pellet, wood powder, glass powder or the like on the base sheet 1 itself.
[0033]
Of course, these methods for forming the color hiding property and pattern on the substrate sheet 1 itself can be used in combination with the printing method and the transfer method described above.
[0034]
Further, when the calendar method is used as a method of manufacturing the base material sheet 1 with concealing property, the same method, that is, a method of forming a color concealing property or a pattern on the base material sheet 1 itself, or these methods and the above-described methods. The concealability and pattern can be formed on the base sheet 1 by a method using a printing method, a transfer method, and the like in combination.
[0035]
The reason for laminating the transparent polypropylene resin layer 5 on the surface of the concealing base sheet 1 in the decorative sheet of the present invention is that it has design properties, pattern layer protection and scratch resistance, abrasion resistance, chemical resistance, etc. It is because it expresses.
[0036]
As a method for laminating the concealing base sheet 1 and the transparent polypropylene resin layer 5 in the decorative sheet according to the first, second, and third aspects of the present invention, a polypropylene resin is formed on the base sheet. There are an extrusion laminating method in which a resin is melt extruded from a T die, a coextrusion method in which both resins are melt extruded from a T die, and the like.
[0037]
Among these, the extrusion laminating method is preferably used because it has the highest productivity.
[0038]
The polypropylene resin used in the surface resin layer of the present invention may have a whitening elongation of 150% or more and a breaking elongation of 150% or more.
[0039]
The term “whitening elongation” as used herein refers to the formula (1−l ₀ ) / l ₀ × 100 (%) when the distance between the marked lines when the film expansion part is whitened in the tensile test in JIS Z 1702 is l. Elongation obtained (l ₀ : initial distance between marked lines).
[0040]
Further, the elongation at break is the elongation at break according to JIS Z 1702. As polypropylene satisfying these two conditions, compatible rubber components such as styrene-butadiene rubber, ethylene-propylene random copolymer, and the like, atactic Examples of the polypropylene include many components, such as a polypropylene having an isotactic index of 98 or less, and a random copolymer polypropylene.
[0041]
The thickness of the polypropylene resin layer 5 after extrusion is preferably between 30 and 200 μm. If it is too thick, it may crack when bent, and if it is too thin, scratch resistance will be low.
[0042]
Further, an antioxidant may be added as appropriate when extruding into a film as the surface resin layer and in order to prevent thermal oxidation of the resulting product, and a light stabilizer may be added in order to prevent deterioration due to ultraviolet rays.
[0043]
The type and amount of these additives are not particularly limited, but a combination of those commonly used for olefin resins is sufficient.
[0044]
The problem here is the laminate strength between the base sheet 1 and the polypropylene resin layer 5.
[0045]
In order to obtain particularly sufficient strength, the anchor coat layer 3 is applied to the base sheet 1 (with the pattern layer 2 provided), and the adhesive resin layer 4 and the polypropylene resin layer 5 are formed on the anchor coat layer 3. Is known, and ozone gas is sprayed onto the extruded resin that becomes the adhesive resin layer 4.
[0046]
The ozone treatment apparatus for spraying ozone gas to the extruded resin to be the adhesive resin layer 4 may be a general one, and is not particularly limited.
[0047]
The amount of ozone treatment is low concentration, high flow type and high concentration, low flow type, which cannot be generally stated. However, if the flow rate is too high, there may be adverse effects such as film cracking of the molten resin and temperature drop. As an ozone concentration, an ozone concentration of 20 to 50 g / Nm ³ and an ozone flow rate of 1 to 10 Nm ³ / hour are favorable.
[0048]
However, when co-extruding an adhesive resin layer such as maleic acid-modified polyethylene resin or ethylene- (meth) acrylic acid copolymer, sufficient room temperature laminate strength can be obtained by the above method. The laminate strength below cannot be obtained.
[0049]
Here, in order to make the sheet of the decorative sheet of the present invention have both the laminate strength at normal temperature and high temperature and does not cause whitening during bending, the present inventors use a resin used for the adhesive resin layer 4. as is solved by graft polymerization modified random polypropylene resin (carbonyl group content in the modified random polypropylene 1g is that 0.02 mmol eq) Ru with the added resin hydrogenated styrene-butadiene rubber within 20% maleic anhydride I found something to do.
[0050]
In other words, polyethylene modified with an unsaturated carboxylic acid or its anhydride has a high laminate strength at room temperature, but significantly decreases at high temperatures, particularly at 90 ° C. or higher, and homopolypropylene modified with an unsaturated carboxylic acid or its anhydride. However, no decrease is seen even at 100 ° C., but the strength itself at room temperature is low.
[0051]
On the other hand, when a resin in which 20% of hydrogenated styrene butadiene rubber is added to the inside of a modified random polypropylene resin graft-polymerized with maleic anhydride (the carbonyl group content in 1 g of the modified random polypropylene is 0.02 mmol equivalent) is used. A stable laminate strength up to 100 ° C. can be obtained.
[0053]
On the other hand, if the amount of the rubber component exceeds 30%, cohesive failure within the adhesive resin starts relatively easily, and a certain degree of strength reduction occurs.
[0054]
On the other hand, if the rubber component amount is less than 10%, the stress relaxation inside the adhesive resin becomes insufficient and delamination occurs.
[0055]
Examples of the unsaturated carboxylic acid or anhydride thereof include acrylic acid, methacrylic acid, maleic acid, phthalic acid, citraconic acid, itaconic acid, and anhydrides thereof.
[0056]
The amount of these unsaturated carboxylic acid units or anhydride units is preferably 1 × 10 ⁻⁴ or more and 1 × 10 ⁻¹ mmol equivalent or less as a carbonyl group per 1 g of the composition.
[0057]
Sufficient effect in the following amounts 1 × 10 ^-4 mmol equivalents of units of unsaturated carboxylic or anhydride thereof contained by denaturation do not express, the effect of improving the adhesiveness even 1 × 10 ^-1 millimole equivalents or more Get smaller.
[0058]
Rubber components that are highly compatible with polypropylene added to the adhesive resin include conjugated diene elastomers such as ethylene-butadiene rubber and styrene-butadiene rubber, hydrogenated styrene elastomers such as hydrogenated styrene-butadiene rubber, and ethylene. -Butene copolymer, ethylene-propylene (diene) copolymer, etc. are mentioned.
[0059]
Further, in the present invention, the anchor coat layer 3 provided at the interface between the adhesive resin 4 and the base sheet 1 is an isocyanate curable resin that forms a urethane bond by a reaction between a polyol component and an isocyanate component, and further includes a main component. When using an isocyanate curable resin consisting of two types of polyester polyol and urethane-modified polyester polyol, it is possible to improve the quick drying property of the cured coating film and further improve the laminate strength while maintaining the flexibility of the anchor coat layer 3. In addition, it is possible to obtain a decorative sheet having a laminate strength excellent in not only heat resistance but also cold resistance and weather resistance and good productivity.
[0060]
When the mixing ratio of the polyester polyol and the urethane-modified polyester polyol is 20 to 80% by weight of the polyester polyol and 80 to 20% by weight of the urethane-modified polyester polyol, the cured coating is performed while maintaining the flexibility of the anchor coat layer 3. The rapid drying property of the film and the development of the laminate strength can be further improved. This is because if the amount of the polyester polyol component is larger than this, the flexibility cannot be maintained, and on the other hand, if the amount of the urethane-modified polyester polyol is large, the quick drying property and the lamination strength are not sufficiently exhibited.
If the main component constituting the anchor coat layer 3 is a urethane-modified polyester polyol alone, the flexibility of the anchor coat layer 3 is maintained, but the onset of the laminate strength is delayed, and there is a possibility that floating or deviation occurs during the manufacturing process. There is.
[0061]
In addition, when the main component constituting the anchor coat layer 3 is a polyester polyol alone, the quick-drying property of the cured coating film of the anchor coat layer 3 is maintained and the laminate strength is sufficiently fast, but the flexibility of the anchor coat layer 3 is low. There is a possibility that floating may occur due to a load such as an environmental change.
[0062]
Furthermore, when isophorone diisocyanate is mixed as each isocyanate component used in the anchor coat layer 3, the cohesive strength and flexibility of the anchor coat layer 3 are moderately improved, and the room temperature laminate strength, heat resistant laminate strength, and laminate strength after environmental tests are improved. It was found that a decorative sheet with high strength can be obtained.
[0063]
The blending amount of each isocyanate component is preferably 30 to 98% by weight of isophorone diisocyanate and 2 to 70% by weight of the other isocyanate component in the total amount of the isocyanate component. If there is more isophorone diisocyanate component, the reaction will be slow, so there will be a problem that it will float and shift in the manufacturing process. On the other hand, if there are many other components, cohesion and flexibility will not be sufficient and will float due to environmental changes. This is because.
[0064]
The isocyanate component to be combined is not particularly limited in the present invention. For example, one or more selected from hexamethylresin isocyanate, xylylene diisocyanate, mesitylene diisocyanate, tolylene diisocyanate, 4,4-diphenylmethane diisocyanate or the like A mixture of two or more kinds can be suitably used.
[0065]
In particular, 4,4-diphenylmethane diisocyanate is used because it is very active and can improve the adhesion to polypropylene even in a small amount.
[0066]
Moreover, although the gravure method (gravure printing method, gravure coating method) is used suitably as the formation method of the anchor coat layer 3, it is not limited at all.
[0067]
In this case, the thickness of the anchor coat layer 3 is preferably between 0.5 and 5 μm. If it is too thick, the absolute value of the laminate strength tends to be low, and if it is too thin, it is difficult to form a layer uniformly, and the adhesiveness may be inferior in a portion where the layer is not formed.
[0068]
In some cases, in order to obtain a feel on the surface of the decorative sheet and a further design feeling, the transparent polypropylene resin layer 5 on the decorative sheet surface is provided with a concave pattern 5a, and filling ink is embedded in the concave portion (wiping). However, it is also preferable to provide the topcoat layer 6 on the outermost surface of the polypropylene resin layer 5.
[0069]
As a method for applying the concave pattern 5a, a normal hot-pressure embossing method may be used, and the method is not limited at all.
[0070]
When the T-die extrusion method is used as a method for producing the polypropylene resin layer 5 (two-layer coextrusion film forming method of the adhesive resin layer 4 and the polypropylene resin layer 5), a chill roll for cooling and solidifying the molten resin is used. A method is generally used in which a concave pattern is provided on the surface, the extruded resin is embossed between a chill roll and a press roll, and the concave pattern 5 a is provided on the surface of the polypropylene resin layer 5.
[0071]
Further, it is also preferable to embed ink in the recessed portion of the applied recessed pattern 5a and to provide the topcoat layer 6 on the outermost surface of the polypropylene resin layer 5, but these methods are made of conventional vinyl chloride resin. It can be carried out in the same manner as the wiping process and top coat process performed on the decorative sheet.
[0072]
【Example】
<Example 1>
As shown in FIG. 1, as a base sheet 1, a random polypropylene resin is coated with 6% by weight of inorganic pigment, 0.2% by weight of phenolic antioxidant, 0.3% by weight of hindered amine light stabilizer, and blocking prevention. Using a sheet having a thickness of 70 μm obtained by melt-extruding a resin to which 0.2% by weight of an agent is added, the sheet surface is subjected to corona treatment, and then image ink (produced by Toyo Ink Manufacturing Co., Ltd.) by gravure printing method; The pattern layer 2 was formed by applying a wood grain pattern using Lamister.
[0073]
Further, a two-component curable urethane anchor coating agent (manufactured by Toyo Ink Mfg. Co., Ltd .; EL510 (polyester polyol) as a main ingredient; 50% by weight; Mitsui Takeda Chemical Co., Ltd .; A520) Urethane modified polyester polyol) is used in a mixture of 50% by weight, using 4,4 as isocyanate, 5% by weight of diphenylmethane diisocyanate, 50% by weight of isophorone diisocyanate and 45% by weight of hexamethylene diisocyanate. The mixture was mixed at a ratio of 1 to obtain a two-component curable urethane anchor coating agent.) Was applied by a gravure printing method to form an anchor coating layer 3 having a thickness of 2 μm.
[0074]
Separately, 0.2% by weight of a phenolic antioxidant, 0.3% by weight of a hindered amine light stabilizer, 0.3% by weight of a hindered amine light stabilizer, and a benzotriazole UV absorber are added to a homopolypropylene having an isotactic index of 90 as the transparent polypropylene resin layer 5. Resin to which 0.5% by weight and 0.2% by weight of an antiblocking agent were added, and a modified random polypropylene resin graft-polymerized with maleic anhydride as the adhesive resin layer 4 (the carbonyl group content in 1 g of the modified random polypropylene was 0. 02 millimolar equivalent, Izod impact strength 1000 N / m, hydrogenated styrene butadiene rubber 20% added) between the cooling roll and the pressure roll subjected to the conduit embossing through the base sheet 1 Co-extrusion is further performed, and the adhesive tree is immediately before lamination with the base sheet 1. The surface of the anchor coat layer 3 on the substrate sheet 1 on which the pattern layer 2 has been applied by spraying ozone gas onto the co-extruded random polypropylene resin surface to be the layer 4 with an ozone treatment device and simultaneously performing lamination and embossing. In addition, the 65 μm thick polypropylene resin layer 5 embossed with the concave pattern 5 a was laminated on the surface via the adhesive resin layer 4 having a thickness of 15 μm, but it could be laminated without any problem.
[0075]
A top coat layer 6 having a thickness of 6 μm is applied to the outermost surface of the transparent polypropylene resin layer 5 on which the concave pattern 5a of the laminated laminate is applied, using the urethane top coat agent, and the present invention shown in FIG. A decorative sheet was obtained.
[0076]
<Example 2>
In Example 1 above, a mixture of 10% by weight of EL510, 10% by Mitsui Takeda Chemical Co., Ltd .; 90% by weight of A520 is used as the main component of the anchor coat agent used for the anchor coat layer 3 A decorative sheet was prepared in the same procedure as in Example 1 except that the anchor coating agent was used, and a decorative sheet of Example 2 was obtained.
[0077]
<Example 3>
In Example 1 above, except that the composition of the isocyanate component blended in the anchor coat agent used in the anchor coat layer 3 was changed to hexamethylresin isocyanate alone, a decorative sheet was prepared in the same procedure as in Example 1, A decorative sheet of Example 3 was obtained.
[0078]
<Comparative Example 1>
In Example 1, except that a modified polyethylene resin graft-polymerized with maleic anhydride was used for the adhesive resin layer 4, a decorative sheet was prepared in the same procedure as in Example 1, and the decorative sheet of Comparative Example 1 was prepared. Obtained.
[0079]
<Comparative example 2>
A decorative sheet was prepared in the same procedure as in Example 1 except that it was a modified homopolypropylene resin graft-polymerized with maleic anhydride on the adhesive resin layer 4 in Example 1 to obtain a decorative sheet of Comparative Example 2. It was.
[0080]
<Comparative Example 3>
Modified random polypropylene resin graft-polymerized with maleic anhydride on the adhesive resin layer 4 in Example 1 (the carbonyl group content in 1 g of the modified random polypropylene is 0.02 mmol equivalent, the Izod impact strength is 1000 N / m, inside the ethylene propylene rubber) A decorative sheet was prepared in the same procedure as in Example 1 except that the additive amount was 20%), and a decorative sheet of Comparative Example 4 was obtained.
[0081]
<Comparative example 4>
In Example 1 above, a decorative sheet was prepared in the same procedure as in Example 1 above except that the anchor coat agent using EL510 was used as the main component of the anchor coat agent used for the anchor coat layer 3; And a decorative sheet of Comparative Example 4 was obtained.
[0082]
Thus, for each decorative sheet obtained in Examples 1 to 3 and Comparative Examples 1 to 4, a urethane-modified polyester polyol / polyisocyanate-based adhesive was roll-coated on a hot-dip galvanized metal plate. 5 g / m ² (dry) is applied to provide an adhesive layer, the metal plate is heated at 200 ° C. for 3 minutes, bonded to the base sheet side of the decorative sheet with a rubber roll, and then rapidly cooled in a water tank to form a metal decorative plate. Obtained.
[0083]
The metal decorative plate thus obtained is bent at a low temperature of 5 ° C., and the presence or absence of bending whitening is compared and shown in Table 1.
[0084]
Further, Table 2 shows the result of measuring the interlayer strength of the decorative sheet on the metal decorative plate and the result of measuring the interlayer strength after SWOM1000h of the metal decorative plate.
[0085]
[Table 1]

[0086]
[Table 2]

[0087]
【The invention's effect】
As described above, the decorative sheet of the present invention does not use any vinyl chloride, so there is no concern about environmental problems, it has heat resistance against high-temperature application during processing of a metal decorative board, and has excellent weather resistance. In addition, it is possible to provide a decorative sheet that does not cause bending whitening at low temperatures.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing an example of a decorative sheet according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Base material sheet 2 ... Pattern layer 3 ... Anchor coat layer 4 ... Adhesive resin layer 5 ... Polypropylene resin layer 5a ... Recessed pattern 6 ... Top coat layer

Claims (3)

Apply urethane anchor coating agent to the base sheet surface consisting of paper, olefin resin, acrylic resin, polyester resin or polyvinyl alcohol resin,
A polypropylene resin layer containing a homopolypropylene having an isotactic index of 90 and a modified random polypropylene resin graft-polymerized with maleic anhydride (the content of carbonyl groups in 1 g of modified random polypropylene is 0.02 mmol equivalent). %, The main component of the urethane anchor coat agent is an isocyanate curable resin comprising a mixture of polyester polyol and urethane-modified polyester polyol. A decorative sheet characterized by that.   When the main ingredient component contained in the urethane-based anchor coating agent is considered to be 100% by weight, the main ingredient component is composed of a mixture of 20 to 80% by weight of polyester polyol and 80 to 20% by weight of urethane-modified polyester polyol. The decorative sheet according to claim 1. When the total isocyanate component contained in the urethane anchor coating agent is considered to be 100% by weight, the isocyanate component is composed of a mixture of 30 to 98% by weight of isophorone diisocyanate and 2 to 70% by weight of other isocyanate components. The decorative sheet according to claim 1 or 2, wherein the decorative sheet is provided.

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