JPH0732892B2 - Scratch-resistant matting material and method for producing the same - Google Patents

Description

TECHNICAL FIELD The present invention relates to a matte material having a matte surface with excellent scratch resistance.

[Conventional technology]

Matting materials that have a matte surface such as decorative materials are often used because they can suppress the reflection of light to make it feel calm and make it difficult to see the irregularities of the base material. .

There are, for example, the following two methods for forming the matte surface, but each has its drawbacks.

A method of baking after coating using a silicone baking type paint containing a matting agent. In this method, since the matting agent is contained, the scratch resistance of the obtained film becomes weak. Further, since the baking time is long and the baking temperature is high, it is difficult to apply it to a plastic film having a low softening point.

A method of irradiating ionizing radiation after coating with an ionizing radiation curable coating material containing a matting agent. In this method, although the time required for curing is short, the scratch resistance of the film obtained by containing the matting agent becomes weak. When the ionizing radiation-curable paint is cured, the gloss of the matte surface may vary depending on the energy intensity of the ionizing radiation to be irradiated, the distribution, the temperature caused by irradiation, environmental conditions, the solvent composition in the paint, etc. Even after that, it is extremely difficult to keep the gloss of the product constant, for example, the gloss changes with time.

In addition, in this specification, "scratch resistance" shall mean that it is not scratched when the surface is rubbed 20 times with steel wool # 0000.

[Problems to be solved by the invention]

Therefore, it is an object of the present invention to provide a decorative material having strong scratch resistance of the obtained film, which is hardened in a short time and whose gloss is easily fixed. Further, it is preferable to provide a matting material which is not inconvenient in production even when a thermoplastic film is used as a base material.

[Means for solving problems]

In the present invention, the coating amount is 2 μm to 10 μm at the time of coating provided along the fine unevenness on the matte surface of the matte substrate having the matte surface with the fine unevenness having a height difference of 1 μm to 15 μm on the surface. A gist of a scratch-resistant matte material having a scratch-resistant layer composed of a cross-linked cured film is provided. Further, the present invention provides a glossy matte surface having fine irregularities having a height difference of 1 μm to 15 μm. A method for producing a scratch-resistant matting material, which comprises coating the matting surface of a matte substrate having a matting surface with an ionizing radiation-curable coating along a minute unevenness of 2 to 10 μm, and then irradiating with ionizing radiation. Is also the gist.

In the present invention, as the base material 1, any material can be used as long as it has a matte surface composed of minute irregularities 2, and the surface may be printed or colored if necessary.

For example, the substrate 1 may be a plastic film having a matte surface with minute unevenness having a height difference of 1 μm to 15 μm, and the plastic film may be a polyethylene terephthalate film, a polyethylene film, a polypropylene film, or polyvinyl chloride. A film, a polyvinylidene chloride film, a polycarbonate film, a polyamide (nylon) film, a polystyrene film, an ethylene / vinyl acetate copolymer (EVA) film can be used, and among them, a polyethylene terephthalate film, a polycarbonate film, and a polyvinyl chloride film are preferable. .

In addition, the following materials can be used as the material for the base material: bleached kraft paper, titanium paper, linter paper, paper board, paper such as gypsum board paper, wood base material such as wood, plywood and particle board. , Gypsum board such as gypsum board, gypsum slag board, fiber cement board such as pulp cement board, asbestos cement board, wood chip cement board, GRC and concrete, metal foil or sheet such as iron, aluminum and copper, and the above Complex of each material, etc.

The matte surface on the surface of the base material 1 made of the above-mentioned materials is formed with the minute irregularities 2. The height difference of the minute unevenness 2 is 1 μm
Is preferably about 15 μm to 15 μm, more preferably 2 μm to 10 μm in terms of appearance and ease of providing the scratch resistant layer 3 described later.
m. When the height difference is too small, the scratch-resistant layer 3 is provided and the matte feeling is lost, and gloss appears. When the height difference is too large, the scratch-resistant layer 3 is evenly provided along the unevenness. Becomes difficult.

As a method of providing the minute unevenness 2, a sandblast method,
There are a solvent high temperature treatment method in which a solvent is allowed to act at a high temperature, a method of adding a matting agent at the time of manufacturing a substrate (in particular, a kneading method of manufacturing a film using a masterbatch containing a matting agent), and the like. In the last method, the matting agent is distributed in the substrate, so that it is not always appropriate when it is desired to increase the transmittance. In addition to this, a method of coating with a matting paint containing a matting agent may be used. When using matting agents, silica, calcium carbonate,
Alternatively, an inorganic substance such as titanium oxide, a polyethylene resin particle, or an organic substance such as Teflon powder may be used.

The crosslinked cured film 3 provided along the minute irregularities on the matte surface can be formed by applying and curing a known thermosetting resin coating, but the curing time is short and when curing Application of ionizing radiation curable paint, because it does not require heat,
It is preferably formed by irradiation with ionizing radiation.

The ionizing radiation curable coating material can be prepared using an ionizing radiation curable resin such as unsaturated polyester, polyether acrylate, polyester acrylate, epoxy acrylate, urethane acrylate, spiro stal acrylate, polybutadiene and polythiol polyene. In addition to the above ionizing radiation curable resin, a bifunctional monomer such as neopentyl glycol diacrylate, tripropylene glycol diacrylate, diethylene glycol diacrylate, 1,6-hexanediol diacrylate, or the like may be used for the ionizing radiation curable paint. Trifunctional monomers, for example, polyfunctional monomers such as trimethylolpropane triacrylate, pentaerythritol triacrylate, and dipentaerythritol hexaacrylate can be mixed and used. As a polyfunctional monomer, other than this, tetrafunctional,
A pentafunctional or hexafunctional monomer can also be used.

Ionizing radiation curable coating, the above ionizing radiation curable resin, in addition to the polyfunctional monomer added as necessary, in the case of curing by ultraviolet irradiation, a photoinitiator, for example, acetophenones, benzophenone, Michler's ketone, benzoin, Benzyl methyl ketal, benzoyl benzoate, α-amyloxime ester, tetramethyl thiuram monosulfide, thioxanthones and the like, and sensitizers such as n-butylamine, triethylamine, tri-
It is advisable to add n-butylphosphine or the like.

As a method for applying the ionizing radiation curable paint, any of blade coating method, gravure coating method, rod coating method, knife coating method, reverse roll coating method, kiss coating method, spray coating method, offset gravure coating method and the like can be used. However, the gravure coating method, the reverse roll coating method, or the offset gravure coating method is preferable because a thin film can be coated without uneven thickness.

The coating amount at the time of coating is preferably 2 μm or more in order to obtain sufficient scratch resistance, and if it is up to about 20 μm, it is possible to follow the fine irregularities of the lower layer.
If the coating amount is excessively large as compared with the height difference of, the height difference of the unevenness 2'on the surface of the film becomes small, and thus the gloss increases and the matting effect decreases (Fig. 3). 10μ
It is preferably m or less.

In the case of coating with the above coating amount, by making the coating amount smaller than the unevenness height difference of the base material, the unevenness 2'of the coating surface can be obtained.
The height difference between the two becomes smaller, the gloss increases, and the matting effect does not decrease.

As a result of applying the above coating amount, a film of 2.5 μm is formed on the surface of the original base material having minute unevenness 2 of 5 μm in height difference, and the height difference of unevenness 2 ′ of the film surface is about 2.5 μm. Become.

After application, the electron beam used for curing is emitted from various electron beam accelerators such as Cockloft-Walton type, Vandegraph type, resonance transformer type, insulating core transformer type, linear type, dynamitron type, or high frequency type. Those having an energy in the range of 50 to 1000 KeV, preferably 100 to 300 KeV are used, and as the ultraviolet rays, ultraviolet rays using a light source such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a xenon arc, or a metal halide lamp. Those originating from the source are used.

[Operation and effect of invention]

The scratch-resistant matting material of the present invention has a height difference of 1 μm for matting.
Since the surface of the base material with minute irregularities of ~ 15 μm has a cross-linked cured film with a coating amount of 2 μm to 10 μm when coating along the minute irregularities, the outermost surface contains a matting agent. It has excellent scratch resistance.

Further, the scratch-resistant matting material of the present invention has only a coating along the fine unevenness on the surface of the base material having the fine unevenness for matting, so that the thickness of the coating is simply controlled. , Can be adjusted to a constant gloss.

According to the method for producing a scratch-resistant matte material of the present invention, it is possible to efficiently manufacture a matte material having a large scratch resistance and easily maintaining a constant gloss in a short time, and to reduce the variation in quality. it can.

It should be noted that the desired gloss can be easily obtained by changing the thickness of the crosslinked cured film.

Since the scratch-resistant matte decorative material of the present invention has the above-mentioned characteristics, it can be applied to a wide range of applications, but particularly when a plastic film that cannot be baked at high temperature is used as a base material. It is particularly suitable for CRT anti-glare filters, membrane switches, displays, nameplates, calculator surface materials, etc. that require matte plastic film scratch resistance when using plastic films as the base material. High value.

Examples As a matte base material, a polyester film (manufactured by Teijin Ltd., one surface of which is matt-treated by a sandblast method,
SM-188-S, Roughness difference of matte surface 4μm, matte surface 60
Using a reflective gloss value of 4.7), the matte surface is coated with a UV-curable resin paint that does not contain a matting agent (Daika Seika Co., Ltd., Seika Beam PHC, polyester acrylate type) by the gravure coating method, Then on the coated surface 12.5
An ultraviolet ray was irradiated by passing it under the condition that two ultraviolet ray lamps each having an output of 160 W / cm provided in cm were installed at a speed of 10 m / min.

60 of the surface of the obtained scratch-resistant matte polyester film
The reflection gloss value is 1 when the coating amount is 2 μm (when dry).
It was 2.0, and when it was 4 μm (dry), it was 71.2. The former one had a very matte surface, and the result of scratch resistance test with steel wool was also good.

It should be noted that substantially the same results were obtained by using a paint obtained by removing the photoinitiator and the sensitizer from the paint used above and using an electron beam for curing.

Comparative example Both sides are smooth polyester film (manufactured by Teijin Ltd.,
For S type), 7% of microsilica as a matting agent was added to the same ultraviolet curable resin coating material as in Example 1, and the solid content was adjusted to 65% with xylene to further reduce the viscosity. Others were carried out in the same manner as in Example 1,
Ink flow caused by rotation of the gravure cylinder during coating, unevenness due to uneven volatilization of the solvent occurred, and scratches were also observed by a scratch resistance test with steel wool.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a base material used in the present invention, FIG. 2 is a cross-sectional view of a decorative material when a matte surface is provided with a relatively thin film,
FIG. 3 is a sectional view when a relatively thick film is provided. 1 ... Substrate 2 ... Micro unevenness (base material surface) 2 '... Micro unevenness (coating surface) 3 ... Coating

Claims (4)

[Claims] 1. A coating amount which is provided along the minute unevenness on the matte surface of a matte substrate having a matte surface having minute unevenness having a height difference of 1 μm to 15 μm on the surface and a coating amount of 2 μm to 10
A scratch-resistant matte material having a scratch-resistant layer formed of a crosslinked cured coating having a thickness of μm. 2. The scratch-resistant matting material according to claim 1, wherein the crosslinked cured coating does not contain a matting agent. 3. An ionizing radiation-curable coating material is applied along the fine irregularities on the matte surface of a matte substrate having a matte surface having fine irregularities having a height difference of 1 μm to 15 μm on the surface, and 2 μm to 10 μm.
Then, a method for producing a scratch-resistant matte material, which comprises irradiating with ionizing radiation. 4. A method for producing a scratch-resistant matting material according to claim 3, wherein the ionizing radiation-curable coating material does not contain a matting agent.