JPH11268215A - Polyester film for decorative sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the polyester film capable of highly keeping design effect even of a pattern printed layer is damage by a dent or a scratch. SOLUTION: (A) a polyester film for a decorative sheet is used by bonding and arranging (B) a pattern printing layer on the surface of a base material and the color difference ΔE* with the pattern printing layer (B) represented by the formula ΔE*= (L*A-L*B)<2> +(a*A-a*B)<2> +(b*A-b*B)<2> }<1/2> [wherein L*A, a*A and b*A are hues of (A) the polyester film and L*B, a*B and b*B are hues of (B) the pattern printing layer] is 50 or less.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyester film for a decorative sheet. Here, the decorative sheet is
A decorative material (surface material) that is attached to the surface of a base material of various commodities such as various furniture, building materials, and home appliances, and is used by disposing a pattern printing layer on the surface. In addition, a building material (surface material) in which a decorative sheet is bonded to the surface of various base materials and handled as a single product is called a decorative plate. To be arranged.

[0002]

2. Description of the Related Art A vinyl chloride resin sheet is most commonly used as a sheet (film) used between a base material of a decorative board and a pattern printing layer and a decorative sheet. However, when a vinyl chloride resin sheet is used, the plasticizer migrates to the adhesive layer and causes poor adhesion to the base material, or the thermal dimensional stability is poor, so that thermal expansion and contraction causes wrinkles. There are problems such as causing. Furthermore,
It is said that vinyl chloride resin sheets generate chlorine during incineration and also cause acid rain and dioxin. From the viewpoint of environmental protection, there is a demand for decorative sheets that do not use vinyl chloride resin sheets. It is growing.

On the other hand, a decorative sheet is used as a surface material, and therefore, a decorative pattern is usually provided on the surface. Therefore, color tone management is extremely important in order to obtain a delicate contrast between a picture and a shadow.

By the way, since the decorative sheet is a surface material, it cannot avoid contact with, for example, the tip of a cleaning tool or a nail on a limb, and the surface may be damaged. In particular, in the case of strong contact or rubbing, the damage to the damaged part also increases,
The surface or inside of the film may be exposed on the surface of the decorative sheet. When the color tone of the film and the print layer formed on the surface thereof are different, the color tone of the damaged portion is different from the surrounding color tone, so that the damaged portion is conspicuous and the design of the surface of the decorative sheet is greatly impaired.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to maintain a high degree of high designability even when a pattern printing layer is damaged by dents or scratches. It is an object of the present invention to provide a polyester film for a decorative sheet.

[0006]

That is, the gist of the present invention is to provide a polyester film for decorative sheet (A) which is bonded to the surface of a base material and used by disposing a pattern printing layer (B) on the surface. Wherein the color difference ΔE ^{* from the} pattern printing layer (B) represented by the following formula (1) is 50 or less.

[0007]

ΔE ^* = ｛(L ^* A−L ^* B) ² + (a ^* A−a ^* B) ² + (b ^* A−b ^* B) ² ｝ ^1/2 (1)

In the formula (1), L ^* A, a ^* A and b ^* A represent the color tone of the polyester film (A), and L ^* B, a ^* B and b ^* B represent the color tone of the picture printing layer (B). Represent.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The polyester in the present invention refers to a polyester containing an ester group obtained by polycondensation from a dicarboxylic acid and a diol or a hydroxycarboxylic acid.

Examples of the above dicarboxylic acids include terephthalic acid, isophthalic acid, adipic acid, azelaic acid, sebacic acid, 2,6-naphthalenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid and the like. , Ethylene glycol, 1,4-butanediol, diethylene glycol, triethylene glycol, neopentyl glycol, 1,4-cyclohexanedimethanol, polyethylene glycol and the like,
Examples of the hydroxycarboxylic acid include p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid.

Representative polyesters include polyethylene terephthalate, polyethylene-2,6-naphthalate and the like. Polyester used in the present invention,
It may be a homopolymer or a copolymer obtained by copolymerizing the third component.

The polyester film of the present invention has a color tone similar to the color tone of the picture printing layer formed on the surface. Specifically, the polyester printing film (B) represented by the following formula (1) Has a color difference ΔE ^* of 50 or less.

[0013]

ΔE ^* = ｛(L ^* A−L ^* B) ² + (a ^* A−a ^* B) ² + (b ^* A−b ^* B) ² ｝ ^1/2 (1)

In the formula (1), L ^* A, a ^* A and b ^* A represent the color tone of the polyester film (A), and L ^* B, a ^* B and b ^* B represent the color tone of the picture printing layer (B). Represent. In the present invention, the color difference ΔE ^*
Is preferably 45 or less, more preferably 40 or less. If ΔE ^* exceeds 50, the color tone of the pattern print layer and the color tone of the polyester film are greatly different, and the object of the present invention cannot be achieved.

By the way, when various kinds of furniture, doors, and the like are processed for the purpose of decorating the surface, the end face of the decorative board may be used in a part where human eyes touch. Even in such a case, the polyester film of the present invention having a color tone similar to the color tone of the pattern printing layer, without impairing the design of the pattern printing layer,
It can be suitably used.

Wood-based materials are preferred for furniture, building materials, home appliances, and the like. In other words, wood-based colors are preferred because a space surrounded by the color of the wooden skin produced by the Japanese-style house provides mental comfort. In such a case, since the color tone of the picture print layer is yellowish, it is important to adjust the color tone b ^* value. Thus, b ^* values of the polyester film (A) of the present invention preferably satisfies the following formula (2) in relation to the b ^* values of the pattern printed layer (B). That is, the difference between the b ^* value of the polyester film layer (A) and the b ^* value of the pattern printing layer (B) is preferably 20 or less,
It is particularly preferred that it is within 15.

[0017]

| B ^* A−b ^* B | ≦ 20 (2)

The above-mentioned hues (L ^* , a ^* , b ^* ) of the polyester film of the present invention are measured by a color difference meter, and the adjustment can be made by blending a coloring pigment in consideration of concealing properties. . Therefore, the polyester film of the present invention preferably contains a coloring pigment. The color tone of the polyester film of the present invention has an L ^* A value of 20 to
80, the a ^* A value is preferably -10 or more, and the b * A value is preferably -5 or more. The reason is as follows.

As described above, wood-based materials are preferred for furniture, building materials, home appliances, and the like. Since the color tone of the woody material is basically yellow, it is important to adjust the b ^* value.However, by further regulating the color tone of the polyester film to the above range, the color tone of the woody material having a higher design property can be improved. Can be expressed. In other words, when the color tone of the film is out of the above range, the color of the film is different from the color tone of the wood-based material, so that it is difficult to adjust the color tone of the picture print layer provided on the film. Furthermore, as described above, when the decorative plate is used at a site where the end face is in contact with human eyes, the decorative color differs from the color tone of the pattern print layer expressing the woody color tone, and thus the design of the pattern print layer is impaired.

The type of the above-mentioned coloring pigment is not limited as long as it can impart a hue to the film.
Examples include particles of barium sulfate, calcium carbonate, carbon black and the like. These may be surface-treated with an oxide such as aluminum, silicon, or zinc from the viewpoint of improving dispersibility in the polyester and weatherability of the decorative sheet.

Other inorganic coloring pigments include calcium sulfate, asbestin, kaolin, magnesium carbonate, alumina white, zinc white, lead white, basic sulfate,
Sulfate, lithopone, zinc sulfide, antimony white, triiron tetroxide, barium chromate, cadmium yellow, titanium yellow, yellow iron oxide, loess, zinc ferrite, male yellow, lead cyanamide, calcium leadate, red lead graphite, chromium Vermilion,
Bengala, amber, lead red, silver vermilion, cadmium red, cadmium mercury red, antimony vermilion, molybdate orange, graphite, manganese purple, ultramarine blue, navy blue, cerulean blue, gosu, cobalt blue, cobalt purple, zinc chromate, cobalt green, Chrome green, zinc green, chromium oxide, viridian, emerald green, zinc silicate, zinc cadmium sulfide, calcium sulfide,
Examples include strontium sulfide and calcium tungstate.

Incidentally, an organic coloring pigment may be used.
Examples thereof include azo color pigments, phthalocyanine-based, acid dye lakes, basic dye lakes, condensed polycyclic color pigments,
Nitroso-based, alizarin lake-based, metal complex azomethine-based, aniline black, alkali blue and other coloring pigments are exemplified. Further, as the azo coloring pigment, monoazo lake type, monoazo type, disazo type, condensed azo type, metal complex salt azo type and other coloring pigments, and as the condensed polycyclic pigment, anthraquinone type, thioindigo type, perinone type, Colored pigments such as perylene, quinacridone, dioxazine, isoindolinone, quinophthalone, isoindoline phthalocyanine, dioxazine, and anthraquinone are exemplified.

The average particle size of the color pigment is usually selected to be 5.0 μm or less, preferably in the range of 0.01 to 4.0 μm. When the average particle size exceeds 5.0 μm, the surface of the film is excessively roughened, and the quality of the printed surface is deteriorated, and the coloring pigment is liable to drop off from the polyester film surface.

The content of the color pigment is usually 0.1 to 30% by weight, preferably 1 to 20% by weight, based on the polyester. If the content is less than 0.1% by weight, the degree of hiding of the entire film decreases, and the color tone of the original color pigment cannot be expressed. If the content exceeds 30% by weight, the color pigment aggregates in the film. Coarse protrusions are formed and the film strength is reduced.

In the present invention, it is preferable to use titanium dioxide from the viewpoint of the concealability of the film. It is preferable to use a yellow pigment composed of iron oxide and zinc oxide for the following reasons.

Examples of the inorganic yellow pigment include yellow, cadmium yellow, zinc chromate and the like, and examples of the organic yellow pigment include anthraquinone type. However, these yellow pigments are discolored by the heat applied during the production of the polyester film, and the yellow coloring power is likely to be reduced. On the other hand, a yellow pigment composed of iron oxide and zinc oxide is excellent in heat resistance and exhibits a sufficient yellow coloring power.

The yellow pigment composed of iron oxide and zinc oxide contains iron oxide (red) and zinc oxide (white) in a ratio of 1: 4 to 4:
It is preferably a baked pigment prepared by calcination of a 1 (weight ratio) mixture. A calcined pigment having a mixing ratio of iron oxide and zinc oxide outside the above range is inferior in ability to color yellow, so that it is difficult to adjust a target color tone. A more preferable mixing ratio of iron oxide and zinc oxide is 1: 3 to
3: 1 (weight ratio).

The primary particle size of the above calcined pigment is 5.0.
It is preferably not more than μm. Primary particle size is 5.0 μm
If it is larger, the calcined pigment tends to have poor yellow tinting power, and the pigment tends to drop off frequently during film formation. A more preferred primary particle size of the calcined pigment is 0.01 to 4.0 μm. The firing of iron oxide and zinc oxide is preferably performed at a temperature of 700 ° C. or more by a tunnel kiln.

In the present invention, the coloring pigment may be added during the polymerization reaction of the polyester. After the polymerization, the coloring pigment is kneaded and dispersed using, for example, a twin-screw extruder to form a masterbatch. For example, a method of blending in a polyester film can be adopted. As a method of adjusting the content of the color pigment, a method of preparing a master material and diluting the master material with a material substantially not containing a color pigment to adjust the content of the color pigment is effective. In addition,
The coloring pigment may be subjected to a treatment such as pulverization, dispersion, classification, filtration or the like in advance, if necessary.

It is preferable that the polyester film of the present invention has a coating layer on at least one surface in order to improve the adhesiveness with the picture printing layer. The coating agent for the coating layer can be arbitrarily selected from known coating agents, but from the viewpoint of adhesiveness, polyester resin, acrylic resin, polyurethane resin, amino resin, epoxy resin,
A coating agent containing at least one compound selected from the group consisting of an oxazoline resin and a coupling agent is preferable.

As a coating method, for example, Yuji Harazaki,
A reverse roll coater, a gravure coater, a rod coater, an air doctor coater or a coating device other than these can be used as shown in "Coating method" published by Maki Shoten, 1979.

The coating layer in the present invention is preferably provided by in-line coating. In-line coating is a method in which coating is performed in the process of manufacturing a polyester film.Specifically, coating is performed at any stage from melt extrusion of polyester to biaxial stretching, heat setting, and winding. It is. Usually, a substantially amorphous unstretched sheet obtained by melting and quenching, followed by a uniaxially stretched film stretched in the longitudinal direction (longitudinal direction) or a biaxially stretched film before heat setting. Apply. Among these, the method of stretching the film in the lateral direction after applying it to the uniaxially stretched film is excellent. According to such a method, there is an advantage in manufacturing cost because film formation and coating and drying can be performed simultaneously, thin film coating is easy because stretching is performed after coating, and heat treatment performed after coating can be performed. Because of the high temperatures that cannot be achieved by other methods
The film and polyester film adhere firmly to the surface.

The thickness of the coating layer is, as a thickness after drying, usually 0.001 to 10 μm, preferably 0.010 to 5 μm.
μm, and more preferably 0.015 to 2 μm. If the thickness of the coating layer is less than 0.001 μm, the polyester film of the present invention does not have sufficient adhesiveness to the pattern printing layer. Therefore, an ink having good adhesion to the polyester film may be used for the pattern printing layer. You will be restricted. If the thickness of the coating layer is more than 10 μm, the coating layer acts like an adhesive, so that the films wound up on a roll are likely to adhere to each other, so-called blocking. Further, the influence of the color tone of the coating layer is increased, so that not only the originally intended color tone of the polyester film cannot be exhibited, but also the color tone change occurs in the pattern printing layer, and the design may be impaired.

As described above, the decorative sheet is used as a surface material for furniture, household equipment, and the like. Conventionally, furniture and housing equipment (eg, doors, etc.) often have a flat shape, but a shape with a curved surface has come to be adopted due to a change in preference for appearance design. In other words, by giving a wooden surface a curved surface, the point of mental relaxation is evaluated, and such a shape is preferred. In order to satisfy such a purpose, it is required that the decorative sheet be easily deformed and sufficiently conform to the shape of furniture including curved surfaces.

Among the constituent elements of the decorative sheet, the thickest element is a polyester film. Therefore, from the viewpoint of improving the deformability of the decorative sheet, it is required to improve the deformability of the polyester film. To meet such demands,
The polyester film of the present invention contains at least 5 to 30 mol% of an isophthalic acid unit as a dicarboxylic acid component.
It is preferably a copolymerized polyester film contained. If the isophthalic acid units are less than 5 mol%, the deformability of the copolymerized polyester film becomes poor. Further, when the isophthalic acid unit exceeds 30 mol%, thermal dimensional stability is poor in printing and the like, and thermal wrinkles and blisters are easily caused.

The pattern printing layer formed on the surface of the polyester film of the present invention may be a single layer or a multilayer, but generally, the above-mentioned polyester film is used in order to exhibit high design properties. Is provided with an undercoat layer, and various patterns are printed thereon. Finally, various high-design prints such as wood-grain print, ceramic wall-tone print and stone-tone print, and prints using primary colors such as red, yellow, and blue are obtained.

The production of the polyester film of the present invention comprises:
It can be performed as follows. That is, first, the melt-extruded molten sheet is rapidly cooled and solidified on a rotary cooling drum to form an amorphous sheet. Then, at a stretching temperature of usually 70 to 150 ° C, preferably 75 to 130 ° C, usually 2.0 to 7.0.
The amorphous sheet is stretched in one direction (longitudinal direction) at a stretching ratio of, preferably 2.4 to 6 times, to obtain a uniaxially stretched film. For such stretching, a roll or tenter type stretching machine can be used. Then, usually from 70 ° C to 1
3.0 at a stretching temperature of 50C, preferably 80-140C.
The uniaxially stretched film is stretched in a direction perpendicular to the longitudinal direction (transverse direction) at a stretch ratio of up to 6 times to obtain a biaxially stretched film. Subsequently, at 110 to 250 ° C., heat treatment is performed for 1 second to 5 minutes at a stretching or relaxation within 30% or a constant length to improve dimensional stability.

[0038] In the polyester film of the present invention, for example, an edge portion generated during the production thereof, for example, an edge portion cut and separated after transverse stretching may be blended as a recycled material. Also,
The polyester film of the present invention may be formed by laminating polyesters having different color differences as long as the color tone is adjusted to the above range. The thickness of the polyester film of the present invention is usually 10 to 250 μm, preferably 1 to 250 μm.
It is 2 to 200 μm, more preferably 15 to 125 μm.

[0039]

EXAMPLES 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 of the present invention. In addition, the evaluation method in an Example and a comparative example is as showing below. Also,
In the Examples and Comparative Examples, all “parts” of component ratios indicate “parts by weight”.

(1) Color Tone: Using a color analyzer ("TC-1800MKII" manufactured by Tokyo Denshoku Co., Ltd.)
According to the method of JIS Z8722, tristimulus values X, Y, Z
And the color tone (L) of the film according to JISZ8729.
^* , A ^* , b ^* ) were determined, and the color tone was compared using L ^* , a ^* , b ^* values, and ΔE ^* was determined according to the above equation (1).

(2) Coin scratch evaluation: The surface of a decorative sheet provided with a pattern printing layer on the surface of a polyester film is rubbed with a coin, and the printed layer and the polyester film are destroyed. Was examined. When the change in color tone was small and the scratch was not conspicuous, the case where the change in color tone was large and the scratch was conspicuous was evaluated as x, and in the middle thereof, Δ was indicated. In particular, a case where there was little change in color tone was evaluated as ◎.

(3) Concealment: Macbeth densitometer (TD-9)
04 type), and the density of transmitted light under the G filter is measured to determine the degree of hiding. The larger this value is, the higher the hiding power is. The hiding power was defined as A class when the value of the hiding degree was larger than 1.0, B class when 0.1 to 1.0 was smaller, and C class when smaller than 0.1. There is no problem in use as long as the concealing property is B or higher.

(4) Ink Adhesion: The following peel test was performed and evaluated according to the following five-point criteria. First, a printing ink for indigo cello color ("Toyo Ink Manufacturing Co., Ltd." CC
ST39 ”) and the coating thickness after drying is 1.5 μm
Is applied to the film surface and dried with hot air at 80 ° C. for 1 minute to obtain a film for evaluation. Then, the evaluation film was conditioned at 23 ° C. and a humidity of 50% RH for 24 hours.
Nichiban Scotch tape (18mm)
Width) is applied to a length of 7 cm so as to prevent air bubbles from entering, and a constant load is applied on this with a 3 kg manual load roll. Next, the evaluation film was fixed on a substrate arranged in a vertical direction, and 50 cm of 45 cm thread was attached to one upper end of the cellophane tape.
0g weight is connected. Then, the weight is dropped from the same height as the upper end of the cellophane tape. After the weight falls naturally by a distance of 45 cm, the peel test is started in the direction of 180 °.

[0044]

[Table 1] Evaluation 5: No ink was peeled off from the cellophane tape surface. Evaluation 4: Less than 10% of the ink is peeled off from the cellophane tape surface. Evaluation 3: 10 to 50% of the ink is peeled to the cellophane tape side. Evaluation 2: 50% or more of the ink was peeled to the cellophane tape side. Evaluation 1: The ink was completely peeled to the cellophane tape side.

(5) Deformability: 10 cm long, 10 cm wide,
Using a truncated pyramid-shaped mold having a maximum depth of 1 cm, a bottom of 8 cm and a width of 8 cm, the film is heated and then deformed inside the mold by vacuum and pressure. At this time, a film that can be deformed until the film is in close contact with the entire surface of the mold is class A, and a film that can be deformed until it is almost in contact with the mold is class B.
Samples that could not be deformed until they came into close contact with the mold were classified as C class, and samples that could not be deformed at all were classified as D class.

(6) Comprehensive evaluation: The case where the change in color tone due to the coin scratch evaluation was small and high designability could be maintained at a high level was evaluated as ○, and the case where the change in color tone was large and high designability could not be maintained was evaluated as x. In particular, a case where the design was highly maintained during woodgrain printing was rated as ◎.

Example 1 Using a vented twin-screw extruder, with an IV of 0.65, substantially
Particle-free polyethylene terephthalate
Rutile type polyester having a particle size of 0.3 μm
41% by weight titanium oxide, zinc ferrite having a particle size of 0.5 μm
(ZnO ・ Fe _TwoO_Three), 18% by weight, particle size 0.01 μm
Kneading and dispersing 0.05% by weight of carbon black,
A master batch pellet (B) was prepared. Different from this
Using a twin-screw extruder with a polyester (A)
3% by weight of silica having a particle size of 3.5 μm is kneaded and dispersed in
Star batch pellets (C) were prepared. Ferrite above
Zinc is a mixture of iron oxide and zinc oxide in a 1: 1 weight ratio.
And then calcined.

After blending 65% by weight of the polyester (A), 16% by weight of the master batch pellet (B) and 19% by weight of the master batch pellet (C),
It was dried at 0 ° C. for 2 hours, melt-extruded into a sheet by a single screw extruder, and molded on a rotary cooling drum at 30 ° C. to obtain an amorphous sheet. At this time, an electrostatic contact method was adopted. Subsequently, the film was biaxially stretched 2.8 times at 83 ° C. in the longitudinal direction and 3.9 times at 115 ° C., and then heat-treated at a heat setting temperature of 210 ° C. for 3.5 seconds to form a 45 μm thick polyester film ( D) was obtained. The color tone of the obtained polyester film (D) is L
^* Value: 68, a ^* value: 9.1, b ^* value: 27.2 Further, the degree of concealment is 1.7 (concealing property: class A).
Deformability was class B.

Then, a high-design print layer (1) comprising a solid pattern print layer and a wood pattern print layer was provided on the polyester film (D) to obtain a wood pattern decorative sheet (E).
The color tone of the wood pattern print layer is L ^* value: 31.8, a ^* value:
8.8, b ^* value: 17.7. Subsequently, the surface of the decorative sheet (E) was rubbed with a coin, and the coin scratch property was evaluated. When the peeled part of the woodgrain print was carefully observed, a part where the polyester film part of the present invention was exposed was also observed, but the color tone difference between the woodgrain print and the polyester film was small, so the high design property was highly maintained. I was able to do it.

Example 2 After a polyester film (D) was obtained in the same manner as in Example 1, a solid pattern printing layer and a wood pattern printing layer of a dark color slightly different from the color tone of the wood pattern printing of Example 1 were formed. The high-design print layer (2) was provided to obtain a decorative sheet (F). The color tone of the wood pattern print layer is L ^* value: 40.3, a ^* value: 11.
2, b ^* value: 28.7. When the coin scratch property of the surface of the decorative sheet (F) was evaluated, a portion where the polyester film portion was exposed was recognized as in Example 1. However, since the color tone difference between the woodgrain print and the polyester film was small, High designability was maintained at a high level.

Example 3 After a polyester film (D) was obtained in the same manner as in Example 1, a solid pattern print layer and a wood pattern print layer of a dark color slightly different from the color tone of the wood pattern print of Example 1 were formed. A high-design print layer (R) was provided to obtain a decorative sheet (G). The color tone of the wood grain print layer is L ^* value: 53.4, a ^* value: 10.
6, b ^* value: 30.1 When the coin scratch property of the surface of the decorative sheet (G) was evaluated, a portion where the polyester film portion was exposed was recognized as in Example 1. However, since the color tone difference between the woodgrain print and the polyester film was small, High designability was maintained at a high level.

Example 4 After a polyester film (D) was obtained in the same manner as in Example 1, a solid pattern printing layer and a wood pattern printing layer of a dark color slightly different from the color tone of the wood pattern printing of Example 1 were formed. The high design printing layer (S) was provided, and a decorative sheet (H) was obtained. The color tone of the wood pattern print layer is L ^* value: 57.7, a ^* value: 3.
0, b ^* value: 11.3 When the coin scratch property of the surface of the decorative sheet (H) was evaluated, a portion where the polyester film portion was exposed was recognized as in Example 1. However, since the color tone difference between the woodgrain print and the polyester film was small, High designability was maintained at a high level.

Example 5 After a polyester film (D) was obtained in the same manner as in Example 1, a solid pattern printing layer and a wood pattern printing layer of a dark color slightly different from the color tone of the wood pattern printing of Example 1 were formed. The high design print layer (5) was provided to obtain a decorative sheet (I). The color tone of the wood pattern print layer is L ^* value: 57.7, a ^* value: 3.
0, b ^* value: 6.3 When the coin scratch property of the surface of the decorative sheet (I) was evaluated, a portion where the polyester film portion was exposed was recognized as in Example 1. However, since the color tone difference between the woodgrain print and the polyester film was small, High designability was maintained at a high level.

Example 6 In Example 1, polyester (J) was used in which the dicarboxylic acid component was composed of 85 mol% of terephthalic acid units and 15 mol% of isophthalic acid units, and the diol component was composed of ethylene glycol, instead of polyester (A). A polyester film (K) was obtained in the same manner as in Example 1 except for the above. The color tone of the obtained polyester film (K) was as follows: L ^* value: 68, a ^* value: 9.1, b ^* value: 27.
It was 2. The degree of concealment was 1.7 (concealing property: class A), and the deformability was class A.

Next, a high-design print layer (1) composed of a solid pattern print layer and a wood pattern print layer was provided on the polyester film (K) in the same manner as in Example 1, and a wood pattern decorative sheet (L) was formed. Obtained. When the coin scratch property of the surface of the decorative sheet (L) was evaluated, a portion where the polyester film portion was exposed was recognized as in Example 1. However, since the color tone difference between the woodgrain printing and the polyester film was small, High design quality was maintained at a high level.

Example 7 In Example 1, polyester (M) in which a dicarboxylic acid component was composed of 60 mol% of terephthalic acid units and 40 mol% of isophthalic acid units and a diol component was composed of ethylene glycol instead of polyester (A) was used. A polyester film (N) was obtained in the same manner as in Example 1 except for the above. However, drying (vacuum drying) of the melt-extruded raw material was performed at 120 ° C. for 6 hours, and film formation was performed under the following conditions. That is, longitudinal stretching is performed at a temperature of 70 ° C. and 2.8.
Times, transverse stretching 3.9 times at 90 ° C, heat setting 150
C. for 3.5 seconds. The color tone of the obtained polyester film (N) was L ^* value: 68, a ^* value: 9.1, b
^* Value: 27.2. The degree of concealment was 1.7 (concealing property: class A), and the deformability was class A.

Next, a high-design print layer (1) composed of a solid pattern print layer and a wood pattern print layer was provided on the polyester film (N) in the same manner as in Example 1 to obtain a wood pattern decorative sheet (O). . Since the thermal dimensional stability of the polyester film (N) was inferior, flatness defects such as blisters and wrinkles occurred during printing of the wood pattern print layer, making printing difficult. However, when the coin scratch property of the surface of the decorative sheet (O) was evaluated, a portion where the polyester film portion was exposed was observed as in Example 1. However, the color tone difference between the woodgrain print and the polyester film was small. Because of its small size, high design quality was maintained at a high level.

Example 8 A polyester film (P) provided with a coating layer in the following manner
It was created.

(1) An aqueous dispersion of a polyester resin, an aqueous dispersion of a polyurethane resin, an aqueous dispersion of hexamethoxymethyl melamine, and an aqueous dispersion of silicon oxide were respectively 20% by weight, 65% by weight, and 10% by weight on a dry solids basis. And then diluted with water to prepare a coating solution.

(2) The above coating solution was applied to the same polyester film (D) as in Example 1 using a bar coater so that the film thickness after drying became 0.1 μm, and
Telfilm (P) was obtained. The color tone of the obtained polyester film (P) was as follows: L ^* value: 68.5, a ^* value: 9.
2, b ^* value: 28.2. The concealment degree is 1.7.
(Concealing property: class A) and deformability was class B.

Next, on the coated layer of the polyester film (P), a high-design print layer (1) composed of a solid pattern print layer and a wood pattern print layer was provided in the same manner as in Example 1, and a wood pattern decorative sheet (Q ) Got. When the coin scratch property of the surface of the decorative sheet (Q) was evaluated, a portion where the polyester film portion was exposed was recognized as in Example 1. However, since the color tone difference between the woodgrain print and the polyester film was small, High design quality was maintained at a high level. Furthermore, the adhesiveness between the polyester film and the ink was high, and the exposed portion of the polyester film was reduced, which was favorable.

Example 9 The same coating solution as in Example 8 was applied to the same polyester film (K) as in Example 6 using a bar coater so that the film thickness after drying was 0.1 μm. (R) was obtained. The color tone of the obtained polyester film (R) was as follows: L ^* value: 68.5, a ^* value: 9.2,
b ^* value: 28.2. The degree of concealment was 1.7 (concealing property: class A), and the deformability was class A.

Next, a high-quality design printing layer (1) comprising a solid pattern printing layer and a wood pattern printing layer was provided on the polyester film (R) coating layer in the same manner as in Example 1, and a wood pattern decorative sheet (S ) Got. When the coin scratch property of the surface of the decorative sheet (S) was evaluated, a portion where the polyester film portion was exposed was recognized as in Example 1. However, since the color tone difference between the woodgrain print and the polyester film was small, High design quality was maintained at a high level. Furthermore, the adhesiveness between the polyester film and the ink was high, and the exposed portion of the polyester film was reduced, which was favorable.

Comparative Example 1 Using a vented twin-screw extruder, polyester (A) having an IV of 0.65 and containing substantially no particles, having a particle size of 0.3 μm
m, 41% by weight of rutile type titanium dioxide is kneaded and dispersed,
A master batch pellet (T) was prepared. Separately, using a vented twin-screw extruder, 3% by weight of silica having a particle size of 3.5 μm was kneaded and dispersed in the polyester (A) to prepare a master batch pellet (C).

After blending 65% by weight of polyester (A), 16% by weight of master batch pellets (T) and 19% by weight of master batch pellets (C),
It was dried at 0 ° C. for 2 hours, melt-extruded into a sheet by a single screw extruder, and molded on a rotary cooling drum at 30 ° C. to obtain an amorphous sheet. At this time, an electrostatic contact method was adopted. Subsequently, the film was biaxially stretched 2.8 times at 83 ° C. in the longitudinal direction and 3.9 times at 115 ° C., and then heat-treated at a heat setting temperature of 210 ° C. for 3.5 seconds to form a 45 μm thick polyester film ( U) was obtained. The color tone of the obtained polyester film (U) is L
^* Value: 91, a ^* value: 0.8, b ^* value: -4. The degree of concealment was 0.3 (concealing property: class B), and the deformability was class B.

Next, on the polyester film (U),
The decorative sheet (V) was provided with a high-design print layer (1) composed of the same solid pattern print layer and wood grain pattern print layer as in Example 1.
I got The color tone of the wood pattern print layer is L ^* value: 32, a
^* Value: 9.0, b ^* value: 17.0. Then, when the coin scratch property of the decorative sheet (V) was evaluated,
The exposed portion of the polyester film was very conspicuous due to the large difference in color tone between the woodgrain print and the polyester film, and the design was impaired.

Comparative Example 2 After obtaining a polyester film (U) in the same manner as in Comparative Example 1, a high-design print layer (2) consisting of a solid pattern print layer and a wood pattern print layer was provided, and a decorative sheet (W) was prepared. Obtained. The color tone of the wood pattern print layer is L ^* value: 42.1, a ^* value: 1
1.1, b ^* value: 29.1. Subsequently, when the coin scratch property of the decorative sheet (W) was evaluated, the portion where the polyester film portion was exposed was very conspicuous due to a large difference in color tone between the woodgrain print and the polyester film, and the design property was impaired.

Comparative Example 3 After obtaining a polyester film (U) in the same manner as in Comparative Example 1, a high-design print layer (3) composed of a solid pattern print layer and a wood pattern print layer was provided, and a decorative sheet (X) was prepared. Obtained. The color tone of the wood pattern print layer is L ^* value: 54.0, a ^* value: 1
1.0, b ^* value: 32.0. Subsequently, when the decorative sheet (X) was evaluated for coin scratch property, the exposed portion of the polyester film was very noticeable due to the large difference in color tone between the woodgrain print and the polyester film, and the design was impaired.

[0069]

[Table 2]

[0070]

According to the present invention described above, there is provided a polyester film for a decorative sheet, which is capable of maintaining a high degree of high design even if the printed surface of the pattern is damaged by dents or scratches. The industrial value of the present invention is very large.

Claims (6)

[Claims] 1. A polyester film (A) for a decorative sheet which is bonded to a surface of a base material and used by arranging a pattern printing layer (B) on the surface, wherein the polyester film is represented by the following formula (1). The polyester film for decorative board, characterized in that the color difference ΔE ^* from the pattern printing layer (B) to be produced is 50 or less. ΔE ^* = ｛(L ^* A−L ^* B) ² + (a ^* A−a ^* B) ² + (b ^* A−b ^* B) ² ｝ ^1/2 (1) (Equation ( 1) L ^* A, a ^* A, and b ^* A are the colors of the polyester film (A), and L ^* B, a ^* B, and b ^* B are the pattern printing layers (B).
Represents the color tone. ) 2. The polyester film for decorative board according to claim 1, wherein the difference between the b ^* value of the polyester film (A) and the b ^* value of the pattern printing layer (B) satisfies the following formula (2). | B ^* A−b ^* B | ≦ 20 (2) 3. The polyester film (A) contains a coloring pigment in an amount of 0.1 to 30% by weight based on the polyester, the color tone L ^* A value of the film is 20 to 80, the a ^* A value is -10 or more, and b. ^{* The} polyester film for decorative sheets according to claim 1 or 2, wherein the A value is -5 or more. 4. The color pigment according to claim 1, further comprising a color yellow pigment composed of at least iron oxide and zinc oxide.
The polyester film for a decorative sheet according to any one of claims 1 to 3. 5. The polyester film (A) has a coating layer at least on the surface on which the picture printing layer (B) is arranged, and the coating layer is made of a polyester resin, an acrylic resin, a polyurethane resin, an amino resin, an epoxy resin, an oxazoline. The polyester film for a decorative sheet according to any one of claims 1 to 4, further comprising at least one compound selected from the group consisting of a resin and a coupling agent. 6. The polyester film (A) contains at least 5 to 30 isophthalic acid units as a dicarboxylic acid component.
The polyester film for a decorative sheet according to any one of claims 1 to 5, which is a copolymerized polyester film containing mol%.