JP2579292B2 - Manufacturing method of matte film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to a matte film, and more specifically, to provide a matte film having both good matte properties and surface scratch resistance.

(Prior art) Conventionally, various types of synthetic resin films have been widely used in various fields. For example, this synthetic resin film has a glossy surface depending on applications such as a CRT anti-glare filter, a membrane switch, a display, and a nameplate. In many cases, lost matte properties are required.

The matte film can be produced by sandblasting, which involves spraying fine powder onto the surface of the synthetic resin film to roughen the surface, embossing, in which an embossing roll is pressed directly onto the surface of the synthetic resin film, or transparent on the surface of the synthetic resin film A method of applying a paint to a fine uneven shape, a mold method using a mold having a fine uneven shape on the surface, a method of including a matting agent in a synthetic resin film, and applying a paint containing a matting agent to the surface of the synthetic resin film Numerous methods are known, such as a method for performing the method.

Also, synthetic resin films generally have insufficient surface hardness, so there is a problem of scratch resistance that the surface is easily scratched,
As a method of improving the scratch resistance, a method of forming a cured resin layer from a curable resin paint on the surface of a synthetic resin film is known.

Further, as a method of imparting abrasion resistance as well as mattness to a synthetic resin film, a method of combining the above methods is known.

(Problems to be Solved by the Invention) In the above-mentioned conventional method, as a method for simultaneously providing the synthetic resin film with the matting property and the abrasion resistance, a cured resin layer is formed on the surface of the synthetic resin film and then embossed. Although a treatment method has been used, this method has a problem in that since the hardness of the cured resin layer is high, it is difficult to transfer the fine irregularities of the embossing roll, and it is not possible to impart a good matting property.

As a reverse method, a method of embossing a synthetic resin film and then forming a cured resin layer can be considered. In this method, uniformity of the cured resin layer is required. Since the surface has minute irregularities, it is difficult to apply the curable resin paint uniformly, and there is a problem that glossy unevenness or the like occurs in mattability.

There is also a method in which a matting agent is contained in the curable resin paint, and the paint is applied to a synthetic resin film to form a curable resin layer having a matte property. If the amount of the matting agent is increased in order to obtain the matting property, there is a problem that the abrasion resistance of the curable resin layer is reduced, so that a large amount of matting agent cannot be used, and therefore, together with good matting properties, Excellent scratch resistance could not be imparted at the same time.

Accordingly, it is an object of the present invention to economically provide a scratch-resistant and matte synthetic resin film having excellent scratch resistance and excellent matte uniformity.

(Means for Solving the Problems) The object of the present invention is achieved by the following present invention.

That is, the present invention applies a curable resin paint containing a matting agent in an amount of 1 to 10 parts by weight in 100 parts by weight of the curable resin to at least one surface of the synthetic resin film, and then embosses the surface. After processing, the height difference between peaks and valleys on the surface is 0.
This is a method for producing a matte film, characterized by forming a fine uneven shape having a peak width of 1 to 50 μm and a pitch width of the peaks of 0.1 to 50 μm.

(Function) A matte hardening resin layer is formed on at least one surface of the synthetic resin film by a hardening resin paint containing a matting agent, and the embossing treatment is further performed to form a curable resin containing a matting agent. A matte film having uniform mattability and excellent abrasion resistance is economically provided by eliminating problems such as insufficient mattability, uneven gloss, change in gloss, and the like caused only by the paint.

(Preferred Embodiment) Next, the present invention will be described in more detail with reference to preferred embodiments.

FIG. 1 is a diagram schematically showing a cross section of a matte film of the present invention. As shown, the matte film of the present invention has a cured resin layer containing a matting agent on at least one surface of a synthetic resin film 1 as shown in FIG. 2 is formed, and the fine irregularities 3 are formed on the surface thereof.

The synthetic resin film 1 used for the above-mentioned matte film of the present invention may be any conventionally known synthetic resin film, for example, a polyester film, a polyethylene film, a polypropylene film, a polyvinyl chloride film, a polyvinylidene chloride film, a polycarbonate film. Polyamide (nylon) film, polystyrene film, ethylene-vinyl acetate copolymer film and the like are used. In particular, polyester film, polycarbonate film, polyvinyl chloride film and the like are preferable in terms of transparency and various other physical properties.

The synthetic resin film as described above may be a colored film, or may be an uncolored film, and may be a partially colored one, that is, one having a printed pattern or picture. All are performed according to the prior art.

The above-mentioned synthetic resin films may be those whose surfaces have been subjected to a primer treatment or a corona discharge treatment for the purpose of improving the adhesiveness of their surfaces.

If such a synthetic resin film is too thin, it has disadvantages in strength and other aspects, and if it is too thick, it is uneconomical, so the preferred thickness range is about 10 to 10
It is about 0 μm.

In the present invention, a cured resin layer 2 containing an appropriate amount of matting agent is formed on one surface of the synthetic resin film 1 as described above.

The matting agent to be used may be a conventionally known matting agent. For example, any of inorganic substances such as silica, calcium carbonate and precipitated barium sulfate, and organic substances such as polyethylene particles and Teflon powder can be used. If the amount of the matting agent is too large, the abrasion resistance of the curable resin layer is reduced, and if the amount is too small, the matting property is insufficient.
It is in the range of about 1 to 10 parts by weight per part by weight.

The cured resin layer containing the above matting agent is formed, for example, from an ionizing radiation curable paint or a thermosetting paint containing the matting agent. Particularly preferred ionizing radiation-curable paints are electron beam-curable paints and ultraviolet-curable paints, while particularly preferred as thermosetting paints are organosilane-based curable paints containing an organosilane compound as a curing agent.

Electron beam curable paints and ultraviolet curable paints are similar in composition except that the latter contains a photopolymerization initiator or a sensitizer, and generally have a structure as a film-forming component. A polymer having a radical polymerizable double bond therein,
It contains an oligomer, a monomer or the like as a main component and, if necessary, a non-reactive polymer, an organic solvent, a wax, and other additives.

Particularly preferred for the purposes of the present invention are those in which the film-forming component has an acrylate-based functional group, for example, a relatively low molecular weight polyester resin, a polyether resin,
Acrylic resin, epoxy resin, urethane resin, alkyd resin, spiro acetal resin, polybutadiene resin,
Polythiol polyene resin, oligomer such as (meth) acrylate of polyfunctional compound such as polyhydric alcohol, or prepolymer and reactive diluent such as ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N- Monofunctional monomers such as vinylpyrrolidone and polyfunctional monomers, for example, trimethylolpropane tri (meth) acrylate, hexanediol di (meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol Tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth)
It contains a relatively large amount of acrylate, neopentyl glycol di (meth) acrylate, and the like.

By using such a polyfunctional (meth) acrylate-based ionizing radiation-curable coating material, a cured resin layer having excellent surface hardness, transparency, abrasion resistance, scratch resistance and the like can be formed. Further, when such a cured resin layer is required to have high flexibility and shrink resistance, an appropriate amount of a thermoplastic resin, such as a non-reactive acrylic resin or various waxes, is used in the curable paint. The addition can meet those requirements.

Further, in order to make the above-mentioned curable paint an ultraviolet-curable paint, acetophenones, as a photopolymerization initiator therein,
Benzophenone, Michler benzoyl benzoate, α
-Amiloxime esters, tetramethylthiuram monosulfide, thioxanthones, and n-butylamine, triethylamine, tri-n-butylphosphine and the like as photosensitizers can be mixed and used.

Various grades of ionizing radiation curable coatings such as the above-mentioned electron beam or ultraviolet curable coatings are known, and all of them can be easily obtained from the market and used in the present invention.

Conventional techniques can be used as they are for curing, for example, in the case of electron beam curing, Cockloft-Walton type, Bandegraf type, Non-vibration transformer type, Insulating core transformer type, Linear type, Dynamitron type, High frequency 50 to 1,000 KeV, preferably 10 to 10 emitted from various electron beam accelerators such as molds
An electron beam having an energy of 0 to 300 KeV is used, and in the case of ultraviolet curing, an ultra-high pressure mercury lamp, a high pressure mercury lamp,
Ultraviolet rays emitted from a light source such as a low-pressure mercury lamp, a carbon arc, a xenon arc, and a metal halide lamp are used.

As the thermosetting paint, any of the conventionally known thermosetting paints can be used. Particularly preferred for the purpose of the present invention are various organosilane-based curing agents such as carbon funk in the thermosetting paint. These include partial alkoxysilanes, alkyltrialkoxysilanes, tetraalkoxysilanes, or those obtained by partially co-hydrolyzing a combination thereof, or those obtained by adding a hydrolyzate of an alkyltrialkoxysilane and colloidal silica.
Such an organosilane-based curable coating material can form a cured resin layer having particularly good adhesion to a synthetic resin film and extremely high surface hardness.

The curable paint as described above can be prepared by any coating method such as a blade coating method, a gravure coating method, a rod coating method, a knife coating method, a reverse roll coating method, a spray coating method, an offset gravure coating method, and a kiss coating method. The composition is applied on the above-mentioned synthetic resin film, and a gravure coating method, a reverse roll coating method, an offset gravure coating method, etc., which are particularly excellent in the accuracy of the applied thickness, the smoothness of the applied surface, and the like are preferable.

Further, if the amount of the curable paint applied is too small, sufficient surface hardness and abrasion resistance cannot be obtained, and if the amount is too large, a decrease in curing speed or distortion such as curling of the synthetic resin film during curing occurs. Therefore, a thickness (dry thickness) of 1 to 50 μm, particularly 1.5 to 10 μm is preferable. Also, the cured resin layer may be provided on both sides of the synthetic resin film.

The embossing method itself used in the present invention is, for example, any known method such as an etching method, a milling method, a continuous film embossing method using an embossing roll manufactured by an electroforming method, a high-frequency embossing method, or the like. There is no particular limitation. Also, the size of the fine unevenness formed by the embossing method is not particularly limited, but preferably, the height difference between the peaks and valleys of the fine unevenness is about 0.1 to 5
When the pitch is 0 μm and the pitch between the peaks is about 0.1 to 50 μm, more preferable results are obtained.

(Effects) According to the present invention as described above, since the cured resin layer having no scratching agent and having abrasion resistance is hard, it is difficult to emboss, and an appropriate amount of matting agent is added to the cured resin layer. The emboss treatment eliminates uneven gloss caused by uneven application of a curable resin paint containing a matting agent, and has excellent uniformity and excellent scratch resistance. Is easily provided.

Therefore, the matte film of the present invention is very useful for applications where matteness and abrasion resistance are simultaneously required, for example, as a CRT anti-glare filter, a membrane switch, a display, a nameplate, a surface material of a calculator, and the like. .

(Examples) Next, the present invention will be described more specifically with reference to examples and comparative examples.

Example 1 A polyester film smooth on both sides (Teijin Co., Ltd.)
Gravure coating of UV curable resin paint (manufactured by Dainichi Seika Kogyo Co., Ltd., Seikabeam PHC, polyester acrylate) with 1% by weight of micro silica added as a matting agent on one surface of It was then applied at a speed of 20 m / min under two ultraviolet lamps having an output of 160 w / cm and provided at 12.5 cm above the coated surface and irradiated with ultraviolet rays.

Thereafter, embossing was performed using an embossing roll.
The surface of the obtained scratch-resistant matte polyester film of the present invention had a 60 ° reflection gloss value of 70.0, had a matte surface, and had good scratch resistance test results using steel wool.

Comparative Example 1 To the same film as in Example 1, 6% by weight of a matting agent was added to the same UV-curable resin coating material, and the coating was applied in the same manner as in Example 1, and the film was irradiated with ultraviolet rays and cured. However, no embossing treatment was performed. Since this matte film contains a large amount of matting agent, scratches were observed in a scratch resistance test. In addition, the gloss of the matte surface varied, and the gloss changed over time.

Comparative Example 2 The same UV-curable resin paint was applied to the same film as in Example 1 without adding a matting agent, and then the speed was 5 m.
/ min., and the other conditions were the same as in Example 1 to irradiate and cure with ultraviolet rays. Thereafter, embossing was performed, but the cured resin layer had too strong abrasion resistance, so that a satisfactory matte surface could not be obtained without embossing.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a cross section of the matte film of the present invention. 1: Synthetic resin film 2: Cured resin layer 3: Fine irregularities

Claims (3)

(57) [Claims] A curable resin coating containing a matting agent in an amount of 1 to 10 parts by weight in 100 parts by weight of a curable resin is applied to at least one surface of a synthetic resin film, and then the surface is embossed. And the height difference between peaks and valleys on the surface is 0.1-50 μm
A method for producing a matte film, wherein a fine uneven shape having a pitch width between peaks of 0.1 to 50 μm is formed. 2. The method for producing a matte film according to claim 1, wherein the cured resin layer is formed from an ionizing radiation-curable resin paint. 3. The method for producing a matte film according to claim 1, wherein the cured resin layer is formed from an organosilane-based thermosetting resin paint.