JPH06287349A - Polymer particle with special shape and its production - Google Patents

Abstract

PURPOSE:To provide a polymer particle having a special shape and useful as an additive for a coating material. CONSTITUTION:A secondary particle having a shape like a three-dimensional rosary and formed by linking spherical particles of a polymer of an ethylenically unsatd. compd. to each other is provided. The secondary particle has interconnecting voids in a content of 0.5-75vol.% and gives, when used as an additive for a coating material, a coating film excellent in scratch resistance by virtue of the excellent adhesiveness and in matte effect, hiding effect, insulating properties, etc. The particle can exhibit its excellent characteristics also in other fields.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a paint matting material, a concealing property improving material, an additive material such as an anti-blocking material, an insulating film insulating property improving material, a plastic modifier, a chromatographic carrier, and cosmetics. Etc. relating to specially shaped polymer particles.

[0002]

2. Description of the Related Art Polymer particles are added to an organic or inorganic binder, and the binder (here, the binder is a component of a coating material, such as a binder polymer, an organic solvent, a pigment or an inorganic material). It is a generic term for aqueous solutions and other additives that may contain other additives.), Has excellent dispersibility in handling, is excellent in handling safety, and has high elasticity and high binder of particles themselves. The reason is that the formed binder / polymer-particle composite exhibits excellent scratch resistance due to its adhesion to the paint, and has little adverse effect on the weather resistance of the coating film when added to the paint. In recent years, it has been widely used as a matting material for paints, a hiding property improving material, an anti-blocking material, an insulating film additive material, and the like. In particular, the scratch resistance that the adhesiveness with the binder and the elasticity are expressed is far superior to the conventionally used inorganic particles, for example, mica, silica, talc and other additive materials, It has been attracting attention as an additive material.

However, even such polymer particles having excellent adhesiveness, when applied as a coating additive, may lack adhesiveness depending on the combination of the binder type and the polymer type of the polymer particles. There is. This causes the scratch resistance to decrease, and there is a problem that the coated surface is likely to be scratched when the coating material coated with the polymer particles-added coating material is processed or transported.
Further, the matte effect and the hiding property improving effect are inferior to the conventional inorganic particles, and in order to develop a satisfactory matte effect and hiding property, it is necessary to add a large amount of polymer particles, which causes a cost increase. It has been.

In order to solve such a problem, various techniques have been tried in the past. That is, in order to improve the adhesion, which is deeply related to scratch resistance, a reactive functional group is introduced into the polymer of the polymer particles, which is expected to chemically bond with the binder, and an uneven shape is formed on the particle surface. Increase in frictional resistance with the binder or anchor
Some are expected to be effective. Further, as a method for improving the matt effect and the concealing property, there is an attempt to improve the light scattering effect by synthesizing hollow polymer particles as described in, for example, JP-A No. 64-1704. Is made.

[0005]

However, even with these methods, the adhesiveness with the binder, the matting effect, and the concealing property improving effect are not sufficient, and in particular, the lack of scratch resistance caused by the poor adhesion is insufficient. It is a fatal factor for the quality of coating materials. The object of the present invention is to dramatically improve the adhesiveness regardless of the type of binder, and to greatly improve the matting effect and the concealing property, a paint additive, an insulating film insulation improving material, plastic, etc. Another object is to provide polymer particles having a characteristic shape, which can be used as an improved material, a chromatograph, other carriers, and cosmetics.

[0006]

The object of the present invention described above is a secondary particle in which a plurality of spherical fine particles having a polymer of an ethylenically unsaturated compound as a constituent component are bonded to each other in a three-dimensional beaded shape. The secondary particles have one or more pores that open on the surface and penetrate through the inside to a surface different from the above, and the porosity of the pores is 0.5 to 75% by volume. It is preferably achieved by a specially shaped polymer particle characterized by

In the present invention, primary particles made of a polymer are impregnated with a specific ethylenically unsaturated compound, the ethylenically unsaturated compound is polymerized, and then the polymer constituting the primary particles is removed. It is possible to develop a special shape by using this, and when this special shape is used as a paint additive, it improves scratch resistance by improving adhesion, matting effect by visible light scattering and hiding effect. They have found that they can be expressed.

The details of the specially shaped polymer particles according to the present invention will be described below. Special shaped polymer of the present invention
The particles (hereinafter, also simply referred to as invented polymer particles) have spherical fine particles as a main constituent component, which has a polymer of an ethylenically unsaturated compound as a constituent component. Examples of the ethylenically unsaturated compound include methyl acrylate and / or methyl methacrylate, that is, methyl (meth) acrylate or ethyl (meth) acrylate, propyl (meth) acrylate,
Butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, cetyl (meth) acrylate, dodecyl (meth) acrylate, ( Examples thereof include alkyl acrylates such as 2-ethylhexyl meth) acrylate.

As the ethylenically unsaturated compound having a polar group, ethylenically unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, etc., ethylenic unsaturated compounds such as itaconic acid, maleic acid, fumaric acid, etc. Saturated dicarboxylic acid, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, 2,2-bis (hydroxymethyl) ethyl acrylate, 2, (meth) acrylic acid Hydroxyl group-containing compounds such as 3-dihydroxypropyl, 2-aminoethyl (meth) acrylate, 2-N, N-dimethylaminoethyl (meth) acrylate, 2-N, N-diethylaminoethyl (meth) acrylate Aminoalkyl (meth) acrylates such as glycidyl (meth) acrylate, β-methylglycol Jill (meth) acrylate - door,
Examples thereof include glycidyl group-containing compounds such as 3,4-epoxycyclohexylmethyl (meth) acrylate, which are selected as ethylenically unsaturated compounds suitable for the polarity of the synthesis medium in the synthesis of the polymer particles of the present invention described below. Is useful in doing. A homopolymer or a copolymer of one kind or two or more kinds selected from these and the compounds exemplified below can be used as the polymer of the present invention.

Other ethylenically unsaturated compounds include styrene, α-methylstyrene, diaminostyrene, styrenesulfonic acid, isopropenylbenzenesulfonic acid, dimethylaminostyrene (meth) acrylamide, vinyltoluene, chlorostyrene, and (meth). ) Aromatic vinyl compounds such as phenyl acrylate, vinyl acetate,
Vinyl propionate, vinyl esters such as vinyl butyrate, methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether,
Vinyl ethers such as amyl vinyl ether, vinyl halides such as vinyl chloride and vinylidene chloride, acrylamide and alkyl-substituted derivatives thereof, alcohol amides such as N-methyl acrylamide, allyl glycidyl ether, acrylonitrile, etc. Can be illustrated.

In addition to the above, in adjusting the elasticity and mechanical strength of the inventive polymer particles, or in adjusting the dissolution characteristics and the decomposition characteristics necessary for synthesizing the inventive polymer particles, which will be described later, many things are required. A functional cross-linking polymerizable compound may be contained. That is, alkylene di (meth) acrylates such as ethylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate and propylene glycol di (meth) acrylate, Polyfunctional aromatic compounds such as divinylbenzene and trivinylbenzene,
One kind or two or more kinds selected from polyfunctional allyl compounds such as diallyl phthalate can be used, and these are useful for adjusting the conditions for the synthesis of the inventive polymer particles.

Further, in the specially shaped polymer particles, a polymer other than the polymer forming the spherical fine particles, that is, a polymer serving as a subordinate constituent, which is necessary for the synthesis, remains partially. It doesn't matter. That is, as an example thereof, a water-soluble polymer used as a dispersant or the like at the time of synthesis, for example, water-soluble cellulose such as hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, maleated polybutadiene, etc. Water-soluble liquid polybutadiene and polyvinyl alcohols. Further, polyester or polycarbonate which can be adopted as a polymer of the primary particles described later.
, Polyurea, polyamide, and other polycondensation polymers, siloxanes, lactones, lactams, and other polymers by ring-opening polymerization; addition of phenol resin, urea resin, melamine resin, xylene resin, etc. Examples thereof include condensation type polymers and polyaddition type polymers such as polymethylene and polyurethane. If these remain, they become subordinate constituents, and in some cases, adhere to the periphery of the spherical fine particles to deform the spherical appearance, but this does not hinder the main purpose of the present invention.

Regarding the porosity, the polymer particles of the present invention are secondary particles in which a plurality of spherical fine particles are bonded to each other in a three-dimensional beaded shape, and the secondary particles are formed on the surface. It has one or more voids that are perforated and penetrate through the interior to open on a different surface. The porosity of the voids is defined as the ratio of the void volume measured by the mercury porosimetry method to the volume of the polymer particles of the invention. The volume of the polymer particles is n = 20 on the electron micrograph. , The major axis and the minor axis are measured, and the ellipsoidal spherical volume thereof is calculated. The same applies to the following) is required to be 0.5 to 75% by volume, and preferably 3 to 60% by volume.

A polymer having a porosity of less than 0.5% by volume.
In the case of particles, the spherical fine particles which are characteristic of the polymer particles of the present invention cannot be clearly confirmed, and therefore, when the polymer particles of the present invention are used as a coating material, it is considered that the peculiarity of the shape brings about. In addition, it does not contribute much to the improvement of scratch resistance, the matting effect, and the concealment improving effect. Also, 75% by volume
If it exceeds, the mutual bonding of the spherical fine particles becomes incomplete and it becomes difficult to form secondary particles.

The average particle diameter of the inventive polymer particles (the average diameter of the circumscribing spheres of the inventive polymer particles; hereinafter the same) is 0.
The thickness is preferably 3 to 300 μm, more preferably 1 to 120 μm. When the average particle size of the polymer particles of the present invention is less than 0.3 μm, spherical fine particles are recognized as aggregates inside the synthesized secondary particles, but it is difficult to form through holes, and the average particle size is 300 μm
If the average particle size exceeds the above range, the spherical fine particles are easily coalesced with each other or completely separated from each other in the process of synthesis to easily form independent particles, and it is difficult to obtain a desired shape.

The outer shape of the polymer particles of the present invention is not particularly limited, and may be spherical, elliptic spherical, rectangular parallelepiped, cylindrical,
It is selected depending on the application such as flaky shape. However, the spherical shape is the most preferable shape from the viewpoint of versatility of use and ease of synthesis, and the polymer particles of the present invention are preferably substantially spherical shape. The term “spherical” as used herein means that the sphericity (ratio of major axis and minor axis) of the polymer particles of the present invention is 0.75 or more, and “substantially spherical” means 70% by volume or more of the whole. It is said that the polymer particles are spherical.

Considering the case where the polymer particles of the present invention are used as a paint additive, etc., in order to exert their matting effect and concealment improving effect without fail, two surfaces are opened and the inside is opened. The through hole is preferably 0.03
It is preferable that the spherical fine particles having an average particle diameter of .about.75 .mu.m are formed in the remaining space as a result of forming secondary particles by joining in a three-dimensional beaded shape. The secondary particles composed of a plurality of bonded spherical fine particles as described above preferably have a spherical structure as a whole. That is, a large number of spherical fine particles are joined to the macro by connection and / or fusion bonding, and a portion other than the volume occupied by the spherical fine particles is continuous with the surface opening,
It creates voids that penetrate the inside.

It is necessary that the spherical fine particles are joined to each other by connecting and / or fusing. When spherical particles form secondary particles simply by adhering, they can have sufficient mechanical strength for mixing work and painting work when used as an additive material for paint etc. Absent. By bonding the spherical fine particles to each other, it is possible to maintain the mechanical strength sufficient to exert their characteristics.

The polymer particles of the present invention are obtained by impregnating primary particles made of a polymer different from the polymer forming the spherical fine particles with an ethylenically unsaturated compound and polymerizing the ethylenically unsaturated compound, It can be prepared by removing the polymer constituting the primary particles.

The method for producing the polymer particles of the present invention should be called a production method utilizing phase separation of the polymer.
It is the most suitable method for producing constant quality invention polymer particles that can withstand industrial production.

In the synthesis method of the present invention, it is indispensable to use a polymer different from the polymer which is the main constituent of the polymer particles of the invention as primary particles (also referred to as host particles). Here, the polymer different from the polymer forming the spherical fine particles is a polymer different in the kind of the monomer forming the polymer, or even a polymer having the same kind of monomer. There are cases in which the ratios of the polymerization amounts are different, or the molecular weights are different even if the same monomer type and the same copolymerization amount ratio are used. Therefore, as the kind of the polymer, one kind of polymer selected from polymers other than the polymer composed of an ethylenically unsaturated compound and the polymer composed of an ethylenically unsaturated compound, or a mixture of two or more kinds of polymers, Alternatively, a copolymer or the like of an ethylenically unsaturated compound and an unsaturated compound other than ethylenic can be used.

As the polymer of the host particles used in the production of the polymer particles of the present invention, the polymer of the ethylenically unsaturated compound may be the polymer of the ethylenically unsaturated compound exemplified above. Examples of the polymer other than the polymer composed of an ethylenically unsaturated compound include polycondensation polymers such as polyester, polycarbonate, polyurea and polyamide, siloxanes and lactones.
Examples include polymers obtained by ring-opening polymerization of lactams, addition-condensation polymers such as phenol resins, urea resins, melamine resins and xylene resins, and polyaddition polymers such as polymethylene and polyurethane. . Among them, host particles containing a polymer composed of polyester or an ethylenically unsaturated compound as a constituent component are preferable from the viewpoint of easiness of synthesis of the polymer particles of the present invention, removal of the polymer forming the primary particles, and the like.

The method for synthesizing the host particles is not particularly limited, and a usual synthetic method can be used. Examples thereof include emulsion polymerization method, suspension polymerization method, seed polymerization method, dispersion polymerization method, and polymer-emulsion granulation method, which are selected according to the particle size and particle size distribution required for the intended use. be able to.

What is important in selecting the polymer of the host particles is the composition of the host particles and the ethylenically unsaturated compound (hereinafter referred to as spherical fine particle monomer) that produces the polymer which is a constituent of the spherical particles. This is the affinity of the component polymer (hereinafter referred to as primary particle polymer) for the synthesis medium.
The synthetic medium here is a dispersion medium of host particles in a system in which spherical fine particle monomers and host particles coexist.

In order to synthesize the intended polymer particles of the invention, the affinity of the spherical fine particle monomer for the synthesis medium (represented by δm, which is the solubility of the spherical fine particle monomer for the synthesis medium; the same applies hereinafter) is the primary. Affinity of the particle polymer for the synthesis medium (represented by δp, which is the solubility of the monomer of the primary particle polymer in the synthesis medium. The same applies hereinafter).
It needs to be larger. However, the affinity between the spherical fine particle monomer and the primary particle polymer (represented by δmp, the solubility of the spherical fine particle monomer in the monomer of the primary particle polymer, the same applies hereinafter) means the spherical fine particle monomer or It is greater than the affinity of the primary particle polymer for the synthetic medium. That is, δp <δm << δm
p. The difference in affinity with the synthetic medium described here is important because it is an essential requirement for the expression of the phase separation necessary for the synthesis of the polymer particles of the present invention described below. From the viewpoint of industrialization, it is preferable to use an aqueous synthetic medium as the synthetic medium, but a usual organic solvent can also be used if necessary. When an aqueous synthetic medium is used as the synthetic medium,
The lyophilic property means that it is hydrophilic. The hydrophilic balance between the spherical fine particle monomer and the primary particle polymer can be freely adjusted by introducing the above-mentioned ethylenically unsaturated compound having a polar group or the like. Further, adjustment by adding alcohol or the like to the aqueous synthetic medium is also effective.

The polymer constituting the spherical fine particles (hereinafter,
The weight ratio of the spherical fine particle polymer) to the primary particle polymer is also important. The weight ratio of the spherical fine particle polymer to the primary particle polymer is required to be 0.2 to 15 times, preferably 0.5 to 8 times. The spherical fine particle monomer or the spherical fine particle polymer which has undergone phase separation in the host particles under these conditions can be a large number of spherical fine particles, and during the polymerization reaction of the spherical fine particle monomer or after the decomposition of the primary particle polymer and During the removal reaction such as dissolution and / or dissolution, they can be joined to each other by connecting and / or fusing to develop a desired special shape.

In the synthesis, host particles are dispersed in a synthetic medium, spherical fine particle monomers are added to impregnate the host particles, polymerization is carried out using a usual polymerization initiator, and then primary particle polymers are decomposed. And / or the objective can be satisfactorily achieved by removing by dissolving or the like.

As the polymerization initiator used at this time, any of those generally used can be used. Typical examples are water-soluble inorganic peroxides such as hydrogen peroxide and ammonium persulfate, organic peroxides such as cumene hydroperoxide and benzoylperoxide, azobisisobutyronitrile, azobisdimethylvaleronitrile and the like. Is an azo compound. Further, a method generally known as a redox polymerization method in which a metal ion and a reducing agent are used in combination may be used. The polymerization initiator may be added by directly adding it to the synthesis medium, adding a solution that has been emulsified in advance, or
Although addition to the spherical fine particle monomer can be used, the method of adding to the spherical fine particle monomer is preferable.

In order to remove the primary particle polymer from the host particles in which the spherical fine particle polymer is formed, a general method suitable for the primary particle polymer can be used, and it is mainly decomposed. And / or a method of dissolving is adopted. As a typical decomposition method, acid decomposition, alkali decomposition, thermal decomposition and freeze decomposition can be used, and as a dissolution method, elution of the primary particle polymer with a good solvent can be used. What is important is the durability of the spherical fine particle polymer in the removal process of the primary particle polymer. When the spherical fine particle polymer does not have sufficient durability as a property, the polyfunctional cross-linking polymerizable compound described above is previously introduced into the spherical fine particle monomer to make the spherical fine particle polymer a cross-linked polymer. Therefore, means such as improving durability is adopted.

[0030]

Although the elucidation of the action leading to the formation of the polymer particles of the present invention as described above is still insufficient, phase separation due to the affinity balance between the primary particle polymer, the spherical fine particle monomer and the synthetic medium, spherical Primary particle polymer caused by heat generated when the fine particle monomer is polymerized
It is considered that the partial reaction with the local reaction product or the residual primary polymer can be performed during the local reaction with the primary particle polymer and the dissolution and / or decomposition reaction of the primary particle polymer.

[0031]

Reference Example First, before describing the examples of the present application, the synthesis of the primary particles used in the examples will be described. "Synthesis of Primary Particles Nos. A to D" A reaction tank equipped with a stirrer was charged with 778 parts of deionized water (part by weight; the same applies hereinafter), and the stirring speed shown in Table 1 was set. 120 parts of polyvinyl alcohol (PVA217 manufactured by Kuraray Co., Ltd.) having a concentration of 5% by weight was added as a dispersant. Next, an ethylenically unsaturated compound 2 in which 2 parts of azobisdimethylvaleronitrile (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved as an initiator
After adding 00 parts and stirring at a predetermined stirring rotation speed for 5 minutes, the stirring rotation speed was set to 300 rpm. Next, the temperature of the reaction tank was raised to 70 ° C., and the polymerization reaction was performed for 2 hours to synthesize primary particles A to D. Table 1 shows the copolymerization ratios of the ethylenically unsaturated compounds A to D and the average particle diameter of the synthesized primary particles.

"Synthesis of primary particles No. E" In a reaction vessel equipped with a stirrer, 591 parts of deionized water and sodium bisulfite 6
Parts were charged and the temperature was raised to 70 ° C. Then, 300 parts of the ethylenically unsaturated compound having the copolymerization ratio shown in Table 1 and a solution prepared by dissolving 3 parts of ammonium persulfate in 100 parts of deionized water were simultaneously added dropwise in parallel over 2 hours to carry out a polymerization reaction. , Primary particles E were synthesized. Table 1 also shows the average particle diameter of the primary particles E.

"Preparation of primary particles No. F and G" 200 parts of methyl ethyl ketone was charged into a reaction vessel equipped with a stirrer and a cooling condenser, and a polyester resin (Vylonal RV-260 manufactured by Toyobo Co., Ltd.) was charged therein. 50 parts were added. The temperature of the reaction tank was raised to 75 ° C. and the mixture was stirred for 4 hours to completely dissolve the polyester resin. 748 parts of deionized exchanged water in which 2 parts of polyvinyl alcohol (PVA217 manufactured by Kuraray Co., Ltd.) was dissolved in the solution was heated to 80 ° C.
Added over time. Next, an azeotropic tube was attached to the reaction tank, the reaction tank was heated to 100 ° C. to be azeotropically distilled, and methyl ethyl ketone was removed from the reaction tank. F,
Got G. Table 1 shows the primary particle numbers. The stirring rotation number and the average particle diameter at the time of F and G synthesis are also shown.

[0034]

[Table 1]

[0035]

EXAMPLES The present invention will be described in detail below with reference to examples, but the scope of the present invention is not limited by the description of these examples. "Impregnation of primary particle with spherical fine particle monomer, polymerization and removal of primary particle polymer" Table 2 shows the copolymer composition (weight ratio) of spherical fine particle monomer and the type of primary particle polymer used,
Sign of δm-δp (positive or negative), weight ratio of spherical fine particle monomer to primary particle polymer, spherical fine particle polymer
The method for removing the primary particle polymer after production is shown.

[0036]

[Table 2]

Deionized water 899 was added to a reaction vessel equipped with a stirrer.
The department was set up. Next, primary particles were added, and a spherical fine particle monomer in which 1% by weight of an initiator (azobisdimethylvaleronitrile) was dissolved in the spherical fine particle monomer was added dropwise over 2 hours while stirring. After the dropping was completed, stirring was continued for 12 hours to impregnate the primary particles with the spherical fine particle monomer.
Both dropping and impregnation were performed at a liquid temperature of 10 to 20 ° C.
The addition amount of the host particles and the spherical fine particle monomers is such that the weight ratio of the host fine particles and the spherical fine particle monomers corresponds to the weight ratio of the spherical fine particle polymer to the intended primary particle polymer.
Was determined, and the total amount of the host particles and the spherical fine particle monomer was set to 100 parts.

Next, the temperature of the reaction vessel is raised to 70 ° C. and the polymerization is carried out for 12 hours to polymerize the spherical fine particle monomers, and then the primary particle polymer is removed by the removal method described in Table 2 together with the present invention. No. which is a polymer particle. 1 to 12 were obtained. The weight ratio of the spherical fine particle polymer to the primary particle polymer is as shown in Table 2, and this almost corresponded to the weight ratio of the spherical fine particle monomer to the host particle described above. In the table, toluene elution and methyl ethyl ketone elution were carried out for 72 hours in a Soxhlet extraction tube, and alkaline decomposition was carried out in a 10 wt% sodium hydroxide aqueous solution at 80 ° C. for 5 hours. The shape of the polymer particles of the present invention was observed with an electron microscope, and the average particle diameter was measured with an electron microscope photograph.
Further, the porosity was calculated from the mercury intrusion volume under pressure and the average particle size of the polymer particles of the present invention by the mercury intrusion method. Table 3 shows the shape, average particle size, and porosity of the polymer particles of the present invention.

As a comparative example, a shape deviating from the present invention,
No. 2, which is a secondary particle having a porosity. Regarding 13 to 16, the types of primary particles used, the copolymer composition, etc. are shown in Table 2.
The shape, average particle size, and porosity are also shown in Table 3. The meanings of the symbols of the secondary particle shapes in the table are as follows. ⊚: A plurality of spherical fine particles are bonded to each other in a three-dimensional beaded shape to form a secondary particle, and the secondary particle is opened on the surface and penetrates the inside to be opened on a surface different from the above. It has one or more voids and has a substantially spherical outer shape. ◯: A plurality of spherical fine particles are bonded to each other in a three-dimensional beaded shape to form a secondary particle, and the secondary particle is opened on the surface and penetrates the inside to be opened on a surface different from the above. Although it has voids, the outer shape cannot be said to be substantially spherical. (Triangle | delta): Although the surface has an open hole and has one or more pores which penetrate the inside and open on the surface different from the above, spherical particles having a definite shape are not recognized. X: No voids are found penetrating the inside.

[0040]

[Table 3]

"Performance Evaluation as Organic Paint Additive" Polymer particles No. 1 of the present invention described above. 1 to 12 were mixed with acrylic paint (Shinto Paint Co., Ltd .: Shinto-Acrylic # 6000) at a solid content ratio of 1: 1 to give a black AB.
S resin plate (made by Nippon Test Panel Co., Ltd.) has a dry film thickness of 1
It was applied so as to have a thickness of 00 μm and dried at 80 ° C. for 30 minutes. The following performances were evaluated using this as a sample, and the results are shown in Table 4. In addition, as a reference example, secondary particle No. 13 to 16 and commercial acrylic polymer particles (manufactured by Nippon Exlan Co., Ltd .: AR-650 ... This is referred to as No. 17) were evaluated in the same manner, and the results are also shown in Table 4.

[0042]

[Table 4]

Scratch resistance A 10 yen coin is pressed against the surface of the sample at an angle of 45 degrees,
Apply a load of 1 kgf and pull at a speed of 0.5 mm / sec.
The state of occurrence of scratches was examined using a loupe. The meanings of the symbols are as follows. ⊚: No scratch is observed. ◯: The binder was slightly scratched and a thin mark was left. Δ: White and scratched, but there was no interfacial peeling between polymer particles and binder. X: White and scratched, and interfacial peeling of polymer particles is observed. Here, it is the presence or absence of particle peeling from the binder that has a great significance to the scratch resistance. In terms of the above symbols, the performance improvement from x to Δ can be evaluated as a practical performance expression.

Glossiness The glossiness of the sample surface was measured with a glossiness meter (manufactured by Horiba, Ltd.) having an incident (light receiving) angle of 60 °. Here, the glossiness of the coating film of only the acrylic paint as the binder is 83
%, The lower the gloss, the better the matting effect. Using an applicator with a hiding ratio of 100 μm, JIS
The hiding ratio was measured according to K5400.

"Performance Evaluation as an Inorganic Paint Additive" 100 parts of chromic anhydride was dissolved in 810 parts of ion-exchanged water, and 40 parts of calcium oxide was added. To this, 50 parts of colloidal silica (SUN-TECH 30 manufactured by Nissan Kagaku KK) was added to prepare an inorganic coating material. Inventive polymer particles No. 5
5 to 7% by weight was mixed with the inorganic paint, and glycerin (manufactured by Daicel Chemical Industries, Ltd.) was added to the inorganic paint by 3% by weight. Cold-rolled steel sheet test piece whose surface was washed with alkali (manufactured by Nippon Test Panel Co., Ltd .: SPCC-SB: 0.5
× 70 × 150 mm), the polymer-particle composite coating described above was added to No. It was coated with a 5 bar coater and dried at an ambient temperature of 400 ° C. for 30 seconds. Next, annealing was performed at 850 ° C. for 2 hours in a nitrogen atmosphere to evaluate the insulation properties before and after annealing. The results are also shown in Table 4.

As a comparative example, the secondary particle No. 16 and commercially available acrylic polymer particles AR
A coating liquid containing -650 (No. 17) was also evaluated in the same manner, and the results are shown in Table 4.

Examples 1 to 12 in Table 3, that is, the inventive polymer particles satisfying the shape and porosity of the present invention exhibit excellent effects as the coating additive shown in Table 4. I understand. Here, in Examples 8 and 9, the porosity was out of the optimum recommended range of the present invention, and as a whole, the outstanding effect on the performance did not appear, but it was compared with the commercially available acrylic polymer particles (No. 17). The effect on the scratch resistance is recognized, and in Examples 10, 11 and 12, the average particle diameter of the polymer particles of the present invention is out of the optimum recommended range.
Although the performance as a paint additive is difficult to appear, the peculiarity of the shape is recognized. On the other hand, Comparative Examples 13, 1
In No. 6, the porosity in the present invention was too small, and the peculiarity of the shape, which is the feature of the present invention, was lost, and in the performance as a paint additive, a difference from the commercially available acrylic polymer particles was recognized. It's gone. Further, in Comparative Example 14, the porosity was too large, the bonding of the fine particles was insufficient, and the particles were in a partially decomposed state, and the shape intended by the present invention was not obtained. Although the shape of the polymer particles of the present invention was not obtained in Comparative Example 15, it is considered that this is due to the balance between δm and δp.

Further, it is clear from Table 4 that when the polymer particles of the present invention are used as an inorganic coating additive, the deterioration of the insulating property after annealing is suppressed to a low level. As a result of observing the coating film after annealing with an electron microscope, conventional acrylic polymer
In the inorganic coating film to which the particles and Comparative Example 16 which is a secondary particle outside the present invention were added, after the secondary particles and the acrylic polymer particles were decomposed by annealing, the base material of the part was exposed. On the other hand, in the case of adding the polymer particles of the present invention, it is considered that the inorganic coating continuously covers the surface of the base material, whereby the insulating property after annealing is well expressed.

From the above Examples and Comparative Examples, the specially shaped polymer particles according to the present invention exhibit excellent characteristics depending on the shape characteristics, and the shape characteristics are the primary particle polymer and the spherical fine particle monomer. It can be seen that it is expressed by adoption of −.

[0050]

INDUSTRIAL APPLICABILITY The present invention described in detail above is a secondary particle in which a plurality of spherical fine particles are bonded to each other in a three-dimensional beaded shape, and the secondary particle has an opening on the surface and penetrates the inside. It has one or more open pores on the surface different from the above,
With polymer particles of unprecedented shape, its adhesion to inorganic and organic binders is dramatically improved,
This makes it possible to develop scratch resistance and improve the insulating property after annealing. Needless to say, this feature is useful not only as a paint additive but also as a modifier for various plastic materials. The characteristic of the shape exerts an effect on the scattering of visible light, and as a paint additive, it greatly contributes to the matting effect and the hiding rate improvement.
It is fully expected that this effect will be effective not only as a paint additive but also as a cosmetic material.

Claims (3)

[Claims] 1. A secondary particle in which a plurality of spherical fine particles containing a polymer of an ethylenically unsaturated compound as a constituent component are bonded to each other in a three-dimensional beaded shape, and the secondary particle is opened on the surface. Special shaped polymer particles having one or more pores that are perforated and penetrate the inside to open on a surface different from the above, and the porosity of the pores is 0.5 to 75% by volume. . 2. The average particle size of secondary particles is 0.3 to 300.
The specially shaped polymer particles according to claim 1, wherein the specially shaped polymer particles have a size of μm and are substantially spherical. 3. A primary particle composed of a polymer different from the polymer forming the spherical fine particles is impregnated with an ethylenically unsaturated compound, and the ethylenically unsaturated compound is polymerized to form the primary particle. The method for producing specially shaped polymer particles according to claim 1 or 2, wherein the polymer that has been formed is removed.