JP6115588B2 - Organic matte - Google Patents

Description

The present invention relates to an organic matting material having excellent transparency and high matting effect, which can be widely used in various applications including paints and resin molded products.

2. Description of the Related Art Matting coating compositions using inorganic materials such as finely divided silicic acid or organic fine particles as a matting material have been well known. Among these, most inorganic substances such as finely divided silica are amorphous and excellent in matting properties, but have a problem of causing whitening and hindering the color tone of the ground because of poor transparency.

On the other hand, organic fine particles such as acrylic, urethane, and nylon have been proposed as organic matting materials because they have good transparency and are easy to obtain matte properties without impairing the color tone of the base (Patent Document 1). 2).
However, these organic fine particles are spherical or substantially spherical, and it is necessary to increase the amount of addition in order to obtain a higher matting effect, and there is a problem that the handling property at the stage of coating is remarkably lowered.

As a technique that can solve these problems, amorphous polycarbonate resin particles have been proposed (see Patent Document 3). However, the organic fine particles used there are limited to polycarbonate resin. For example, when mixed with acrylic paint and ink, there is a problem that the difference in refractive index between the paint and ink resin is large and the transparency is lowered. there were.

JP 2001-288400 A JP 2004-51901 A JP 2007-233329 A

The present invention provides an organic matting material having excellent transparency and high matting effect that can be widely used in various applications including inks, paints and resin molded products.

The organic matte material according to the present invention has the following features: (1) irregularly shaped resin fine particles having an irregular shape obtained by pulverizing a polymer in which 50% by weight or more of all polymer components are made of polyacrylonitrile (resin fine particles obtained by pulverizing fine particle aggregates) An organic matting material characterized by having a circularity of 0.80 to 0.90 and a volume average particle diameter of more than 4 μm and 20 μm or less, (2) 50% of all polymer components Amorphous resin fine particles (excluding resin fine particles obtained by pulverizing fine particle aggregates) having an irregular shape obtained by pulverizing a polymer composed of polyacrylonitrile at a weight percentage of not less than% by weight and having a circularity of 0.80 to 0.90. The volume average particle diameter is more than 4 μm and not more than 20 μm, and on the polyethylene terephthalate film is a solvent-based acrylic binder (Vanaresin: Shin-Nakamura Chemical Co., Ltd., resin concentration: 35% by weight, diluent solvent Methyl ethyl ketone / toluene = 1/1) Methyl ethyl ketone 50 parts by weight and the 60 ° gloss value of amorphous resin fine particles of 3.5 was applied to parts by weight of the coating composition film sample surface glossiness relative to 100 parts by weight In order to satisfy less than 30, the coating film and resin molded product obtained by adding this organic matting material have excellent transparency and matting properties, and various applications including paints and resin molded products Can be used widely.

If the organic matte material of the present invention is used, a high matte effect can be obtained with a small amount of addition, so that it is possible to reduce the decrease in transparency of paints and resin molded products, which has been a problem with conventional matte materials. Further, it is possible to obtain paints, ink compositions, resin molded products, and the like having both transparency and matting properties, such as matte coatings that make use of the color tone of the base and optical materials that are excellent in transparency.

The enlarged micrograph which showed the amorphous resin fine particle obtained in Example 3 is shown.

The shape of the organic matte material of the present invention is indefinite. In the present invention, an indeterminate shape means an image in which a particle is viewed from one direction (particle projection image) and has irregularities around the image, and how much is 1.0 from 1.0 indicating a perfect circle with a circularity defined by the following equation: Judgment is made based on the smaller value.
Circularity of particle projection image = (circumference of a circle having the same area as the particle projection area) / (perimeter of particle projection image)
Average value of circularity of particle projection image = circularity of spherical particle The above circularity can be measured using, for example, a flow type particle image analyzer “FPIA-3000S” manufactured by Sysmex Corporation.

The circularity of the organic matte material of the present invention is preferably in the range of 0.70 to 0.94, and more preferably in the range of 0.80 to 0.90. Further, since the organic matte material of the present invention has such an irregular shape, the matte property is considered to be improved.

The organic matting material of the present invention can be obtained indefinitely by pulverizing a resin, but the pulverization method therefor is not particularly limited. For example, a general-purpose pulverizer such as a blade mill, a Banbury mixer, a kneader mixer, a roll, etc. It is obtained by supplying to

Further, in the organic matte material of the present invention, the composition of the polymer in which 50% by weight or more of the total polymer components are composed of polyacrylonitrile or polymethyl (meth) acrylate is determined in the resin production stage before pulverization. If 50% by weight or more of the total polymer component is polyacrylonitrile or polymethyl (meth) acrylate, there is no problem even with particles obtained by copolymerization with other polymerizable monomers. Examples of such polymerizable monomers include styrene monomers such as styrene and p-methylstyrene, and acrylic monomers such as ethyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, dimethylaminoethyl acrylate, and diethylaminoethyl acrylate. Acid ester monomers, methacrylate monomers such as ethyl methacrylate, lauryl methacrylate and dimethylaminoethyl methacrylate, alkyl vinyl ethers such as methyl vinyl ether and ethyl vinyl ether, vinyl ester monomers such as vinyl acetate and vinyl butyrate, N-methylacrylamide N-alkyl substituted (meth) acrylamides such as N-ethylacrylamide, nitrile monomers such as methacrylonitrile, divinylbenzene, ethylene glycol Acrylate, ethylene glycol di (meth) acrylate, polyfunctional monomers such as polyethylene glycol mono (meth) acrylate. Such polymerizable monomers may be used alone or in combination of two or more.
The matte material used in the present invention has a polyacrylonitrile or polymethyl (meth) acrylate content of 50% by weight or more, preferably 70% or more, in all polymer components.
In addition, as a monomer to be copolymerized with polyacrylonitrile or polymethyl (meth) acrylate, it is preferable to add a bifunctional or higher methacrylic acid ester monomer from the viewpoint of solvent resistance.

Examples of the resin production method before pulverization include known methods such as an emulsion polymerization method, a suspension polymerization method, a seed polymerization method, and a dispersion polymerization method, and are not particularly limited.

(Volume average particle size in organic matte)
The volume average particle diameter in the organic matting material of the present invention can be measured using, for example, a flow type particle image analyzer “FPIA-3000S” manufactured by Sysmex Corporation.

The volume average particle size of the organic matting material of the present invention is preferably 50 μm or less, and more preferably 1 to 20 μm. If the average particle size is in this range, a high matting effect can be obtained. Conversely, if the average particle size is larger than this range, it is difficult to apply uniformly, causing the coating surface to become rough and causing deterioration in physical properties of the coating. The possibility increases. On the other hand, if it is smaller than this range, it becomes extremely difficult to disperse in the paint or resin kneading stage, and the matting property is remarkably lowered.

  The organic matting material of the present invention can be used by being contained in a resin molded product in addition to a paint and an ink composition. Specifically, first, as a method for producing a paint and an ink composition, the matte paint and the ink composition can be obtained by adding the organic matting material and the binder resin of the present invention to an organic solvent. The binder resin is not particularly limited, and examples thereof include thermoplastic resins, thermosetting resins, and photocurable resins. Specifically, for example, acrylic resins, polyester resins, polyvinyl chloride, polyurethane, silicone resins And melamine resin. In addition, when providing transparency to a coating film, it is preferable to use acrylic resin, acrylic-silicone resin, etc. suitably.

The organic solvent is not particularly limited as long as it dissolves the binder resin. For example, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethylene glycol monomethyl ether (methyl cellosolve), ethylene glycol monoethyl ether (ethyl) Cellosolve), ethyl acetate, butyl acetate, isopropyl alcohol, acetone, anisole, and the like. These may be used alone or in combination of two or more.
In addition, various known additives such as leveling agents, surface modifiers, defoaming agents, and coloring agents such as pigments may be added to the paint and ink composition.

The matting paint and ink composition are, for example, the binder resin is dissolved in an organic solvent and then the organic matting material of the present invention is added, a sand mill, a ball mill, an attritor, a high-speed rotating stirrer, a three roll, etc. Can be produced evenly dispersed and mixed using

The organic matting material of the present invention is not limited to the solvent-based paints and ink compositions as described above, and can also be used in various paints and ink compositions such as solventless, water-based, and powder.

On the other hand, the organic matte material of the present invention can be molded into a thermoplastic or thermosetting matrix resin to produce a resin molded product having a matting effect.
As these matrix resins, resins having excellent transparency, good weather resistance, and rigidity such as polymethyl methacrylate resin, MS resin, polycarbonate resin, and polyester resin are preferably used.
In the resin molded product of the present invention, a resin and an organic matting material are mixed with a mixer, kneaded with a melt kneader, and then extruded to obtain a sheet-like matted resin molded product. A matte resin molded product can also be obtained by taking out the pellet as a pellet after melt-kneading and then subjecting the pellet to injection molding after melting.

The above-mentioned use is an example, and the organic matting material of the present invention can be used for a wide variety of other uses.

Hereinafter, the effects of the present invention will be described with reference to examples and comparative examples, but the scope of the present invention is not limited to these examples.

(1) Preparation of paint composition Solvent-based acrylic binder (Vanaresin: Shin-Nakamura Chemical Co., Ltd., resin concentration: 35% by weight, diluent solvent: methyl ethyl ketone / toluene = 1/1) 50 parts by weight of methyl ethyl ketone per 100 parts by weight Part and 3.5 parts by weight of sample particles were added and stirred for 10 minutes with a homogenizer to obtain coating compositions for various evaluations.

(1) Matte evaluation The matte property is evaluated by the glossiness of a film sample obtained by coating and drying a coating composition.
That is, a coating composition obtained by mixing each sample on a polyethylene terephthalate film (Cosmo Shine # A4300: manufactured by Toyobo Co., Ltd., film thickness: 100 μm) was applied with a bar coater # 15, and was heated in a hot air dryer at 50 ° C. Dry for 30 minutes to obtain a PET film sample. The surface of the film sample was evaluated based on the 60 ° glossiness of a gloss meter (IG-310 manufactured by Horiba). The lower the value, the higher the matteness. As evaluation criteria, a glossiness of less than 20 excellent in matting properties is indicated by 、, a good 20 or more but less than 30 is indicated by ◯, and an inferior 30 or more is indicated by ×.

(2) Transparency evaluation Transparency is evaluated by the total light transmittance of a film sample obtained by coating and drying a coating composition.
That is, as with the matte evaluation, a PET film sample obtained by applying and drying a coating composition in which each sample was mixed was measured with a haze meter (“NDH-2000” manufactured by Nippon Denshoku Industries Co., Ltd.). Total light transmittance was calculated. As evaluation criteria, the total light transmittance is 90% or more as transparency ○, 85% or more and less than 90 as transparency Δ, and less than 85% as transparency ×.

(3) Evaluation of coating appearance The presence or absence of aggregates (spots) on the coated surface of the obtained film sample and the presence or absence of streak-like phenomena (streaks) were visually confirmed and evaluated according to the following criteria.
◯: There are no spots or streaks.
Δ: Slightly irregular or streak
X: There are irregularities or streaks.

< Reference Example 1 >
(1) Synthesis of polyacrylonitrile resin before pulverization An aqueous solution in which 10 parts of polyvinyl alcohol (PVA217 made by Kuraray), 10 parts of sodium sulfate and 1 part of copper sulfate pentahydrate are dissolved in 778 parts of deionized water is made of glass. Charge into the tank. Next, 160 parts of acrylonitrile as a monomer, 40 parts of methyl methacrylate, and 2 parts of 2,2′-azobis (2-methylvaleronitrile) as a catalyst are added to a reaction vessel, and the liquid is stirred. By raising the temperature to 50 ° C. and maintaining the temperature for 5 hours, an aqueous dispersion of a polyacrylonitrile-based resin was obtained.
Thereafter, the polyacrylonitrile resin aqueous dispersion was subjected to solid-liquid separation and dried with a hot air dryer at 70 ° C. to obtain a polyacrylonitrile resin before pulverization according to the present invention.
(2) Preparation of organic matting material The polyacrylonitrile resin before pulverization obtained in (1) is pulverized with a vertical mill (SH-75 type manufactured by Ishikawajima-Harima Heavy Industries), and the organic matting material of the present invention Got.
(3) Preparation of coating film Using the organic matte material obtained in (2), a coating composition was prepared to prepare a coating film, and the transparency, matting property and coating appearance were evaluated.

<Example 2 and Reference Example 2 >
The grinding time of Reference Example 1 (2) was changed to obtain an organic matting material of the present invention of different sizes. The coating film was evaluated in the same manner as in Example 1.

< Reference Example 3 >
(1) Synthesis of polymethyl methacrylate resin before pulverization An aqueous solution in which 7 parts of polyvinyl alcohol (PVA217 made by Kuraray), 10 parts of sodium sulfate, and 1 part of copper sulfate pentahydrate are dissolved in 831 parts of deionized water is made of glass. Charge to the reaction tank. Next, 135 parts of methyl methacrylate as a monomer, 15 parts of ethylene glycol dimethacrylate, and 1 part of 2,2′-azobis (2-methylvaleronitrile) as a catalyst are added to a reaction vessel and stirred. While raising the liquid temperature to 50 ° C. and keeping the temperature for 5 hours, an aqueous dispersion of a polymethyl methacrylate resin was obtained. Thereafter, the polymethyl methacrylate resin was dried with a hot air dryer at 70 ° C. to obtain a polymethyl methacrylate resin before pulverization according to the present invention.

<Comparative Example 1>
A matte material of a comparative example was obtained in the same manner as in Example 1 except that the pulverization time was shortened.

<Comparative example 2>
A polymethyl methacrylate resin was obtained in the same manner as in Example 4 except that the number of stirring during the synthesis was increased. The average particle diameter of the obtained polymethyl methacrylate resin before pulverization was 5 μm, and this was used as a matte material.

<Comparative Example 3>
A commercially available polycarbonate resin was pulverized with a vertical mill (SH-75 type manufactured by Ishikawajima-Harima Heavy Industries) to obtain a matting agent. Matting properties and the like of the obtained matting agent were evaluated.

<Comparative example 4>
Commercially available silica fine particles (Fuji Silysia Chemical Psyloid 74) were obtained, and matte properties and the like were evaluated.

It is understood from Table 1 that the organic matting materials of Examples 1 to 4 of the present invention give a coating film having excellent matting properties and transparency. In particular, it can be seen that the transparency evaluated by the total light transmittance is remarkably superior to generally used inorganic fine particles (Comparative Example 4).
Further, even if the main component is polyacrylonitrile or polymethyl methacrylate, the sample particles of Comparative Examples 1 and 2 whose average particle diameter and circularity are outside the scope of the claims are all matte, transparent, and coating film appearance. Cannot be satisfied, and the object of the present invention is not achieved.

  The matting agent of the present invention is particles having a circularity of 0.70 to 0.94, and polymer resin fine particles in which 50% by weight or more of the total polymer components are made of polyacrylonitrile or polymethyl (meth) acrylate, Since the volume average particle diameter is 50 μm or less, the coating film and resin molded product obtained by adding this organic matting material have excellent transparency and matting properties, including paints and resin molded products. It can be widely used for various applications.

Claims (2)

Non-uniform shaped resin fine particles (excluding resin fine particles obtained by pulverizing fine particle aggregates) having an irregular shape obtained by pulverizing a polymer comprising 50% by weight or more of all polymer components of polyacrylonitrile, and having a circularity of 0.80 An organic matting material characterized by having a volume average particle diameter of 0.90 and not more than 4 μm and not more than 20 μm. Non-uniform shaped resin fine particles (excluding resin fine particles obtained by pulverizing fine particle aggregates) having an irregular shape obtained by pulverizing a polymer comprising 50% by weight or more of all polymer components of polyacrylonitrile, and having a circularity of 0.80 0.90, a volume average particle diameter of more than 4 μm and not more than 20 μm, and a solvent-based acrylic binder on a polyethylene terephthalate film (Vanaresin: Shin-Nakamura Chemical Co., Ltd., resin concentration: 35% by weight, diluent solvent: methyl ethyl ketone / (Toluene = 1/1) 60 ° gloss value of the surface of a film sample coated with a coating composition in which 50 parts by weight of methyl ethyl ketone and 3.5 parts by weight of the above irregular resin fine particles are added to 100 parts by weight is less than 30 glossiness Organic matting material characterized by satisfying