TW202134321A - Resin particles and manufacturing method thereof - Google Patents

Abstract

The object of the present invention is to provide resin fine particles capable of maintaining the transparency of a film while giving an anti-blocking effect when added to various resin films. As a solution, the resin fine particles satisfying the following requirements (a) to (c) are provided.

(a)The resin which comprises the resin fine particles contains structural units derived from monofunctional ester-based monomers with one or more aromatic rings and one ethylenically unsaturated group in the molecule, which are 3 to 95% by mass based on the total structural units, and structural units derived from monofunctional ester-based monomers with two or more ethylenically unsaturated group in the molecule, which are 3 to 50% by mass based on the total structural units.

(b)The average primary particle size is 50 to 800 nm.

(c)The conductivity of an aqueous dispersion in which l part by mass of resin fine particles is dispersed in 20 parts by mass of distilled water is 1 to 200 μS / cm.

Description

Resin particles and manufacturing method thereof

The present invention relates to resin fine particles and a method of manufacturing the same.

In recent years, in addition to thinning or lightening of display devices (displays), flexibility is also required. For the transparent plastic film substrates or optical components (polarizer protective film or retardation film, etc.) used in flexible displays, not only high transparency and flexibility are required, but also the ability to withstand the thermal crawling of the display and reduce the display From the point of view of damage caused by moisture in the external air, components are also required to have high heat resistance or moisture resistance. The use of a film containing a cycloolefin-based resin as a main component as a transparent plastic film substrate or an optical member of such a flexible display is currently under discussion (for example, Patent Document 1).

In addition, in the manufacture of plastic films, for the purpose of improving the slipperiness of the films or preventing the films from adhering to each other and becoming difficult to peel off (sticking), most of them add fine particles (anti-sticking agent (anti-sticking agent)). blocking agent)), and various fine particles are being discussed (for example, Patent Document 2 or Patent Document 3).

[Prior Technical Literature]

[Patent Literature]

Patent Document 1: Japanese Patent Application Publication No. 2018-92770

Patent Document 2: Japanese Patent Application Publication No. 2015-214679

Patent Document 3: Japanese Patent Application Laid-Open No. 2015-101698

However, when inorganic fine particles such as silica described in Patent Document 2 are added to a film with a high refractive index and high hydrophobicity such as a cycloolefin resin, there may be a difference in refractive index with the film. Unable to maintain transparency. In addition, when the acrylic crosslinked fine particles described in Patent Document 1 or Patent Document 3 are added, the particles may not be uniformly dispersed in the highly hydrophobic film and agglomerate, causing the film to whiten or fail to exhibit the desired resistance. Stickiness.

The present invention was made in order to improve such a problem, and its subject is to provide resin microparticles which, when added to various resin films including cycloolefin resin films, can impart an anti-sticking effect while maintaining the film’s properties. Transparency.

The inventors of the present invention conducted intensive studies in view of the above-mentioned problems, and as a result, found that the above-mentioned problems can be solved by using specific resin fine particles. The present invention has the following aspects.

[1] A resin fine particle that satisfies the following requirements (a) to (c):

(a) The resin constituting the resin particles contains: 3 to 95% by mass based on the total structural units, derived from a structure of a monofunctional ester monomer having at least one aromatic ring and one ethylenically unsaturated group in the molecule Units, and 3 to 50% by mass based on the total structural units, of structural units derived from multifunctional monomers having two or more ethylenic unsaturated groups in the molecule;

(b) The average primary particle size is 50 to 800 nm; and

(c) The conductivity of an aqueous dispersion obtained by dispersing 1 part by mass of resin fine particles in 20 parts by mass of distilled water is 1 to 200 μS /cm.

[2] The resin fine particles according to [1], wherein the value A represented by the following formula (1) is 0.9 or more and 5.0 or less, and A=(volume average particle diameter of resin fine particles in toluene ÷ average resin fine particles Primary particle size)‧‧‧(1).

[3] The resin fine particles according to [1] or [2], wherein the coefficient of variation of the average primary particle size represented by the following formula (2) is 25% or less,

Coefficient of variation = (standard deviation of the particle size distribution based on the volume of the resin particles ÷ volume average particle size of the resin particles) × 100‧‧‧(2).

[4] The resin fine particles according to any one of [1] to [3], wherein the monofunctional ester system is selected from the group consisting of benzyl (meth)acrylate, phenyl (meth)acrylate and ( One or more of the group consisting of phenoxyethyl meth)acrylate.

[5] A method for producing resin microparticles, which uses at least one water-soluble azo polymerization initiator and emulsifies and polymerizes the following monomer components in an aqueous medium, wherein the monomer components are all monomers Component content: 3 to 95% by mass of monofunctional ester monomers having one or more aromatic rings and one ethylenically unsaturated group in the molecule, and 3 to 50% by mass of monofunctional ester monomers having two or more in the molecule The multifunctional monomer of ethylenically unsaturated group.

[6] The method for producing resin fine particles according to [5], wherein at least one reactive surfactant having an ethylenically unsaturated group is used during emulsion polymerization.

[7] An anti-blocking agent, which is composed of the resin microparticles described in any one of [1] to [4].

[8] A resin composition comprising: the resin fine particles described in any one of [1] to [4], and a resin binder.

[9] An optical member comprising: the resin fine particles according to any one of [1] to [4].

[10] A resin molded body comprising: the resin fine particles according to any one of [1] to [4].

According to the present invention, it is possible to provide resin microparticles which, when added to various resin films including cycloolefin-based resin films, can impart an anti-sticking effect while maintaining the transparency of the film.

[Resin particles]

The resin fine particles of the present invention satisfy the following requirements (a) to (c):

(a) The resin constituting the resin particles contains: 3 to 95% by mass based on the total structural units, derived from a structure of a monofunctional ester monomer having at least one aromatic ring and one ethylenically unsaturated group in the molecule Units, and 3 to 50% by mass based on the total structural units, of structural units derived from multifunctional monomers having two or more ethylenic unsaturated groups in the molecule;

(b) The average primary particle size is 50 to 800 nm; and

(c) The conductivity of an aqueous dispersion obtained by dispersing 1 part by mass of resin fine particles in 20 parts by mass of distilled water is 1 to 200 μS /cm.

In addition, in the resin fine particles of the present invention, the value A represented by the following formula (1) may be 0.9 or more and 5.0 or less.

A=(Volume average particle size of resin particles in toluene ÷ average primary particle size of resin particles)‧‧‧(1)

In addition, in the resin fine particles of the present invention, the coefficient of variation of the average primary particle diameter represented by the following formula (2) may be 25% or less.

Coefficient of variation = (standard deviation of the particle size distribution based on the volume of the resin particles ÷ volume average particle size of the resin particles) × 100‧‧‧(2)

<Monofunctional ester monomer having one or more aromatic rings and one ethylenically unsaturated group in the molecule>

Regarding the monofunctional ester monomer having at least one aromatic ring and one ethylenically unsaturated group in the molecule, one or more selected from the group consisting of: having one in the molecule The above-mentioned (meth)acrylate compounds of aromatic rings such as benzene ring or naphthalene ring, vinyl ester compounds having more than one aromatic ring in the molecule, and allyl compounds having more than one aromatic ring in the molecule Base ester compounds, etc.

In addition, in this specification, "(meth)acrylic acid" means acrylic acid or methacrylic acid, and "(meth)acrylate" means acrylate or methacrylate.

For example, the monofunctional ester-based monosystem includes one or more selected from the group consisting of: benzyl (meth)acrylate, phenyl (meth)acrylate, and phenoxy (meth)acrylate Ethyl, phenoxy polyethylene glycol (meth)acrylate, biphenyl (meth)acrylate, nonylphenyl (meth)acrylate, nonylphenoxyethyl (meth)acrylate, ( Nonylphenoxy polyethylene glycol (meth)acrylate, cumyl phenol (meth)acrylate, cumyl phenoxy ethyl (meth)acrylate, cumene (meth)acrylate (Meth)acrylate compounds such as polyphenoxy polyethylene glycol ester and ortho-phenylphenol (meth)acrylate; vinyl ester compounds such as vinyl benzoate and vinyl naphthoate; allyl benzoate Allyl ester-based compounds such as esters and allyl naphthoate; (meth)acrylic acid in which one or more substituents such as alkyl, hydroxyl, carboxyl, alkoxy, and halogen are bonded to the aromatic ring of these compounds Ester compounds, etc. Among them, from the good degree of reactivity and high From the viewpoint of refractive index, it is preferably at least one selected from the group consisting of benzyl (meth)acrylate, phenyl (meth)acrylate and phenoxyethyl (meth)acrylate, most preferably It is benzyl (meth)acrylate.

Regarding the resin microparticles of the present invention, relative to 100% by mass of the entire structural unit, it contains a monofunctional ester derived from an aromatic ring having more than one aromatic ring and one ethylenically unsaturated group in the molecule at a content ratio of 3 to 95% by mass. It is the structural unit of the monomer. This content ratio is preferably 10 to 80% by mass, more preferably 20 to 60% by mass. By setting the content ratio within this range, the difference in refractive index with the resin film is reduced and the hydrophobicity of the particles is increased. Therefore, the dispersibility of the particles in the solvent such as toluene or the binder resin is improved, and it can be maintained. The transparency of the composition.

<Multifunctional monomers with 2 or more ethylenically unsaturated groups in the molecule>

Regarding a multifunctional monomer having two or more ethylenically unsaturated groups in the molecule, if it has two or more ethylenically unsaturated groups such as vinyl, allyl, and (meth)acryloxy groups in the molecule The compound can be. One or more selected from the group consisting of polyfunctional (meth)acrylic monomers, polyfunctional vinyl monomers, polyfunctional allyl monomers, and the like can be cited.

For example, the multifunctional monosystem may include one or more selected from the group consisting of the following: ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, di(meth)acrylate Base) triethylene glycol acrylate, decaethylene glycol di(meth)acrylate, pentaethylene glycol di(meth)acrylate, 150 ethylene glycol di(meth)acrylate, two 1,3-butylene (meth)acrylate, allyl (meth)acrylate, trimethylolpropane tri(meth)acrylate, neopentyl erythritol tetra(meth)acrylate, penta(meth)acrylate Base) Dineopentyl erythritol acrylate, divinylbenzene, divinylnaphthalene, diallyl phthalate, triallyl isocyanurate, etc. Among these, preferably one or more selected from the group consisting of ethylene glycol di(meth)acrylate and allyl (meth)acrylate.

The resin microparticles of the present invention contain structural units derived from multifunctional monomers having two or more ethylenic unsaturated groups in the molecule at a content ratio of 3 to 50% by mass relative to 100% by mass of the total structural units. This content ratio is preferably 10 to 50% by mass, more preferably 20 to 50% by mass. By setting the content ratio within this range, the solvent resistance of the particles is improved, and deformation of the particles can be prevented when the particles are formulated in the film.

When the content ratio of the structural unit derived from the polyfunctional monomer having two or more ethylenically unsaturated groups in the molecule is less than the above-mentioned range, the degree of crosslinking of the resin fine particles will decrease. As a result, when a resin composition obtained by mixing resin fine particles with a binder is used as a coating liquid, the resin fine particles swell and cause the viscosity of the coating liquid to increase, and there is a concern that the coating workability is reduced. In addition, as a result of the reduction in the degree of crosslinking of the resin fine particles, in applications where the resin fine particles are mixed with a binder and molded (so-called kneading use), when the resin fine particles are heated, the resin fine particles are likely to be melted or deformed. When the content ratio of the structural unit derived from the polyfunctional monomer having two or more ethylenic unsaturated groups in the molecule is more than the above range, no improvement in the effect corresponding to the amount is observed, which may increase the production cost. situation.

〈Other structural units〉

The resin fine particles of the present invention may contain other structural units within a range that does not impair the effects of the present invention. There are no particular limitations on the monomer that becomes the source of other structural units. For example, one or more selected from the group consisting of: methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate , (Meth)acrylate monomers such as isobutyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, etc.; 2-hydroxyethyl (meth)acrylate Ester, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate and other hydroxyalkyl (meth)acrylates; 2-(meth)acryloyloxyethyl succinic acid, 2- (Meth)acryloyloxy ethyl phthalic acid, 2-(meth)acryloyloxy Ethylhexahydrophthalic acid, 2-(meth)acryloyloxyethylmaleic acid and other carboxylic acid-containing (meth)acrylates; vinyl acetate, vinyl propionate, vinyl butyrate Vinyl ester monomers such as esters.

In addition, when a styrene-based monomer uses a water-soluble polymerization initiator to produce resin fine particles by emulsion polymerization, the monomer is likely to remain, and the dispersion stability during polymerization may be reduced. Therefore, the resin microparticles of the present invention preferably do not contain structural units derived from styrene-based monomers. In addition, the term "does not contain a structural unit derived from a styrene-based monomer" here means "does not contain a structural unit derived from a styrene-based monomer only to the extent that the effect of the present invention is not inhibited."

The resin fine particles of the present invention contain other structural units at a content ratio of 0 to 94% by mass relative to 100% by mass of all structural units. This content ratio is preferably 10 to 80% by mass, more preferably 30 to 70% by mass.

<Average primary particle size>

The average primary particle size of the resin microparticles of the present invention is 50 to 800 nm, preferably 50 to 300 nm. By setting the average primary particle size to be equal to or less than the above upper limit, the resin fine particles become less likely to fall off from the film, so it is easy to maintain the transparency of the film, and it becomes easy to prevent contamination in the manufacturing process. Moreover, by setting it as the above-mentioned lower limit or more, it becomes easy to ensure the anti-sticking performance of a film.

In the present invention, the average primary particle size of the resin fine particles can be measured by the Coulter method, for example, the method described in the examples.

Although particles of the size of this region have a problem of being easy to aggregate during polymerization, the resin microparticles of the present invention exert an excellent aggregation inhibiting effect. By setting the average primary particle diameter of the resin fine particles within the above range, when the resin fine particles are used as a slip agent or anti-sticking agent for various films, the transparency of the film can be maintained and the thickness of the film can be reduced. This can contribute to the miniaturization or weight reduction of products using various films.

<Conductivity>

Regarding the resin fine particles of the present invention, the conductivity of the aqueous dispersion obtained by dispersing 1 part by mass of the resin fine particles in 20 parts by mass of distilled water is 1 to 200 μS /cm, preferably 1 to 100 μS /cm. By setting the conductivity within this range, the transparency of the film can be maintained when the resin fine particles are added to the film.

The electrical conductivity can be adjusted by controlling the amount of water-soluble components contained in the resin fine particles, especially ionic components. For example, by using a water-soluble azo-based polymerization initiator to polymerize the resin fine particles of the present invention, the increase in the conductivity of the aqueous dispersion caused by the residue of the polymerization initiator can be suppressed.

<Value A>

The value A represented by the following formula (1) of the resin fine particles of the present invention is preferably 0.9 or more and 5.0 or less.

A=(Volume average particle size of resin particles in toluene ÷ average primary particle size of resin particles)‧‧‧(1)

The value A is a standard for the degree of aggregation of resin fine particles in a dispersion of resin fine particles prepared when a film containing resin fine particles is produced. By setting this value to be equal to or less than the above upper limit, aggregation of resin fine particles is less likely to occur in the coating liquid prepared using this dispersion, and it becomes easier to maintain the transparency of the film.

<Coefficient of Variation>

The coefficient of variation is measured by using a laser diffraction scattering particle size distribution measuring device to determine the particle size distribution of resin fine particles, and then using this particle size distribution, it is calculated by the following formula (2). Specifically, when a laser diffraction scattering particle size distribution measuring device is used to obtain the average primary particle size of the resin fine particles, it can be obtained together.

Coefficient of variation = (standard deviation of the particle size distribution based on the volume of the resin particles ÷ volume average particle size of the resin particles) × 100‧‧‧(2)

The coefficient of variation of the particle size of the resin particles is preferably 25% or less, and more preferably 20% or less. By setting the coefficient of variation within this range, when particles are added to the film, the film is less likely to be whitened due to voids caused by the shedding of coarse particles.

[Manufacturing Method of Resin Microparticles]

Regarding the method for producing resin microparticles of the present invention, conventionally known methods for producing resin microparticles can be used without limitation. For example, a method of emulsifying and polymerizing a monomer component in an aqueous medium, wherein the monomer component contains: a monofunctional ester-based monomer having at least one aromatic ring and one ethylenically unsaturated group in the molecule And a multifunctional monomer having two or more ethylenically unsaturated groups in the molecule. In this case, it is preferable to use at least one water-soluble azo polymerization initiator as the polymerization initiator. In addition, when the resin microparticles are produced by emulsion polymerization, a mixture of monomers can be emulsified in a medium in the presence of a surfactant, and polymerization can be carried out in the presence of a polymerization initiator.

In the present invention, it is preferable to set it as a method for producing resin fine particles, which uses at least one water-soluble azo polymerization initiator and emulsifies monomer components in an aqueous medium, wherein the monomer The components are based on the total monomer components: 3 to 95% by mass of monofunctional ester monomers having one or more aromatic rings and one ethylenically unsaturated group in the molecule, and 3 to 50% by mass A multifunctional monomer having two or more ethylenically unsaturated groups in the molecule.

The "monofunctional ester monomer having one or more aromatic rings and one ethylenically unsaturated group in the molecule" used in the method of producing resin particles "Saturated polyfunctional monomer" uses the monomers described in [Resin Microparticles], respectively. In addition, the monomers described in [Resin Fine Particles] that become the source of other structural units can be used.

The amount of these monomers can be the same as that described in [Resin Fine Particles].

In particular, with respect to 100% by mass of the total amount of monomers used, it is preferable to use 3 to 95% by mass of a monofunctional ester system having at least one aromatic ring and one ethylenically unsaturated group in the molecule. Monomer", 3 to 50% by mass "multifunctional monomer having two or more ethylenically unsaturated groups in the molecule".

〈Emulsion polymerization〉

The emulsion polymerization in this manufacturing method can be carried out by a conventional emulsion polymerization method, for example, a monomer dropping method, a pre-emulsification method, a one-time injection polymerization method, etc., can be used, but the particle size distribution is narrow and the scale is small. For the resin particles, the monomer dropping method is preferably used.

Emulsification polymerization is preferably carried out using a reaction vessel with a stirring function. The polymerization temperature varies depending on the type of monomer or polymerization initiator used, but it is preferably in the range of 30 to 100°C. In addition, the polymerization time is preferably 2 to 10 hours.

In the method for producing resin fine particles of the present invention, the aqueous dispersion obtained after polymerization can be washed. The washing method may use centrifugal washing, cross flow filtration washing, or the like.

In addition, when the resin microparticles of the present invention are obtained by emulsion polymerization, a reactive emulsifier can be used to directly dry without washing the aqueous dispersion obtained after polymerization, and the washing step can be omitted.

In the method for producing resin fine particles of the present invention, the aqueous dispersion obtained after polymerization can be dispersed in an organic solvent such as alcohol, toluene, and ketone. In this dispersed state, steps such as classification to remove coarse particles through a screen can be carried out. In addition, when it is mixed with a cycloolefin resin or the like in this state to obtain a resin composition containing a cycloolefin resin, it may be difficult to remove the dispersion medium from the dispersion afterwards. Therefore, it is preferable to perform a step of removing the dispersion medium using a dryer such as a spray dryer, and dispersing in a solvent (preferably an organic solvent) again after obtaining the dried powder.

In the dry powder of the resin fine particles dried by the spray dryer, the resin fine particles are aggregated with each other to form a block (hereinafter referred to as a fine particle block). In order to uniformly disperse the resin fine particles in the film, after obtaining the above-mentioned dry powder, it is preferable to perform a step of pulverizing the agglomerates of fine particles. Thereby, the resin fine particles become close to the primary particles, and the dispersibility to the organic solvent or the resin constituting the film is improved. The pulverization step can be carried out in the state of dry powder or in the state of being dispersed in the organic solvent used. Either way, conventional methods can be used. For example, in terms of dry type, the use of blade mills, super rotors, and jet mills, which are mechanical pulverizers, can be cited. Methods such as nano-grinding mills (jet mills) and the like include the use of bead mills, ball mills, hammer mills, etc. in terms of wet methods. method.

〈Aqueous medium〉

The aqueous medium used in the emulsion polymerization can be water alone or a mixture of water and lower alcohols (methanol, ethanol, isopropanol, etc.). From the viewpoint of waste liquid treatment, it is preferable to use water alone.

The amount of the aqueous medium used is preferably in the range of 200 to 2000 parts by mass, and more preferably in the range of 300 to 1500 parts by mass relative to 100 parts by mass of the total amount of all monomers used in the above-mentioned emulsion polymerization. By setting the amount of the above-mentioned aqueous medium to be more than the above-mentioned lower limit, the stability of the particles during polymerization is maintained, and it becomes easy to prevent the generation of agglomerates of resin fine particles after polymerization. By setting the amount of the above-mentioned aqueous medium to be less than or equal to the above-mentioned upper limit, productivity will easily become good.

〈Surface active agent〉

In the above-mentioned aqueous medium, it is advisable to add a surfactant. The surfactant to be added is not particularly limited, but it is preferable to use a reactive surfactant (a surfactant having an ethylenically unsaturated group). also, Anionic or nonionic surfactants can be used as the surfactant, but from the viewpoint of polymerization stability, it is preferable to use one or more anionic surfactants.

The ethylenic unsaturated group contained in the reactive surfactant includes, for example, a vinyl group, a (meth)acryloyl group, and the like. Because of its reactivity, the surfactant is incorporated in the particles and does not remain in the medium (for example, an aqueous medium) in which the resin fine particles are dispersed. In contrast, when a general surfactant that does not have an ethylenically unsaturated group is used, the anionic surfactant may remain in the medium (for example, an aqueous medium) after the polymerization reaction, so it may be incorporated into the film. It becomes the cause of atomization.

Specific examples of anionic surfactants having ethylenically unsaturated groups include, for example, polyoxyethylene-1-(allyloxymethyl) alkyl ether sulfuric acid manufactured by Daiichi Industrial Pharmaceutical Co., Ltd. The trade name of the ester ammonium salt "Aqualon KH-10" and the trade name "Aqualon KH-1025" (25% by weight aqueous solution of "Aqualon KH-10"), as well as polyoxyethylene styrenated allyl phenyl ether sulfuric acid The trade names of ammonium esters are "Aqualon AR-10", "Aqualon AR-20", and "Aqualon AR-1025" (25% by weight aqueous solution of "Aqualon AR-10"); those manufactured by Kao Co., Ltd. belong to polyoxyethylene The trade name of ammonium sulfonyl ether sulfate is "Latemul PD-104"; the product manufactured by ADEKA Co., Ltd. belongs to α -sulfonic acid-ω-(1-alkoxymethyl-2-(2-propenyloxy)ethoxy Yl)-poly(oxy-1,2-ethanediyl)ammonium salt has the trade name "Adeka Reasoap SR-10" and the trade name "Adeka Reasoap SR-20", and belongs to polyoxypropylene allyl ether The trade name of phosphate ester is "Adeka Reasoap PP-70"; the trade name of bis(polyoxyethylene phenyl ether) methacrylate sulfate made by Japan Emulsifier Co., Ltd. is "Antox MS-60"; Examples of reactive anionic surfactants other than reactive anionic surfactants having polyoxyalkylene moieties include sodium p-styrene sulfonate, sodium allyl alkyl sulfonate, etc. Not limited to this. These surfactants may be used individually by 1 type, and may be used in combination of 2 or more types suitably.

Specific examples of nonionic surfactants having ethylenically unsaturated groups include: the product name "Aqualon AN-10" manufactured by Daiichi Industrial Pharmaceutical Co., Ltd. and belonging to polyoxyethylene styrenated propylene phenyl ether "", "Aqualon AN-20", "Aqualon AN-30", "Aqualon AN-5065", and the trade name of polyoxyethylene-1-(allyloxymethyl) alkyl ether "Aqualon KN- 10", "Aqualon KN-20", "Aqualon KN-30", "Aqualon KN-5065"; product names manufactured by ADEKA Co., Ltd. "Adeka Reasoap ER-10", "Adeka Reasoap ER-20", "Adeka "Reasoap ER-30", "Adeka Reasoap ER-40"; product names of polyoxyalkylene ethers manufactured by Kao Corporation "Latemul PD-420", "Latemul PD-430", "Latemul PD-450" "Etc., but not limited to these. These surfactants may be used individually by 1 type, and may be used in combination of 2 or more types suitably.

The amount of the surfactant used is preferably in the range of 0.01 to 5 parts by mass relative to 100 parts by mass of the total amount of all monomers used in the above-mentioned emulsion polymerization. By setting the amount of the surfactant to be more than the above lower limit, it becomes easy to prevent a situation in which the dispersibility of fine particles during polymerization decreases and the polymerization stability also decreases. By setting the amount of the surfactant to be less than or equal to the above upper limit, it becomes easy to prevent the hygroscopicity of the resin fine particles from increasing or the dispersion of the resin fine particles from becoming easy to foam.

<Polymerization initiator>

The polymerization initiator that can be used in the present invention is not particularly limited. Generally known persulfates (for example, ammonium persulfate, potassium persulfate, sodium persulfate, etc.), hydrogen peroxide, azo compounds, and other polymerization initiators can be used.

The amount of the polymerization initiator used in the present invention varies with its kind, but it is preferably used in the range of 0.1 to 5 parts by mass relative to 100 parts by mass of the total amount of all monomers used in the above-mentioned polymerization , More preferably used in the range of 0.3 to 3 parts by mass.

When obtaining the resin fine particles of the present invention by emulsion polymerization, it is preferable to use a water-soluble azo polymerization initiator. As the water-soluble azo polymerization initiator, a polymerization initiator that has been widely used in emulsion polymerization and the like can be used in the past, and a newly developed polymerization initiator for emulsion polymerization and the like can also be used. Examples of water-soluble azo polymerization initiators include, for example, VA-080 (2,2'-azobis(2-methyl-N-(1,1-bis(hydroxymethyl)-2) -Hydroxyethyl) propanamide)), VA-086 (2,2'-azobis(2-methyl-N-(2-hydroxyethyl)-propanamide)), VA-057(2 , 2'-azobis(2-(N-(2-carboxyethyl)carboxamidino)propane)), VA-058(2,2'-azobis(2-(3,4,5, 6,-Tetrahydropyrimidin-2-yl)propane) dihydrochloride), VA-060 (2,2'-azobis(2-(1-(2-hydroxyethyl)-2-imidazoline- 2-yl)propane) dihydrochloride), V-50 (2,2'-azobis(2-carboxamidinopropane) dihydrochloride), V-501 (4,4'-azobis (4-Cyanopentanonic acid)), VA-082 (2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)ethyl]propanamide}) , VA-085 (2,2'-azobis{2-methyl-N-[2-(1-hydroxybutyl)]-propanamide}), VA-044(2,2'-azo Bis[2-(2-imidazolin-2-yl)propane]dihydrochloride), VA-046B(2,2'-azobis[2-(2-imidazolin-2-yl)propane]di Sulfate dihydrate), VA-061 (2,2'-azobis[2-(2-imidazolin-2-yl)propane]) (all manufactured by Fujifilm Wako Pure Chemical Co., Ltd.), 2, 2'-Azobis(2-carboxamidinopropane) dihydrochloride, 2,2'-Azobis{2-[1-(2-hydroxyethyl)-2-imidazolin-2-yl] Propane) dihydrochloride, 2,2'-azobis(1-imino-1-pyrrolidinyl-2-ethylpropane) dihydrochloride, 2,2'-azobis(1- Imino-1-pyrrolidinyl-2-methylpropane) dihydrochloride, 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)-2 -Hydroxyethyl] propylamide} and so on. These polymerization initiators may be used individually by 1 type, and may mix and use 2 or more types.

Among these starters, from the viewpoint of reducing the electrical conductivity of the resin fine particle dispersion, those having no halogens are more preferred. Furthermore, from the viewpoint of good water solubility, VA-086 and VA- are particularly preferred. 057.

When obtaining the resin fine particles of the present invention by emulsion polymerization, use other than water-soluble azo polymerization initiators such as sodium persulfate, potassium persulfate, ammonium persulfate, potassium persulfate/sulfurous acid When sodium hydrogen or the like is used as a polymerization initiator, if the obtained resin particles are added to the cycloolefin resin, the transparency may be reduced. Compared with the case of using the above-mentioned persulfate as the polymerization initiator, when the water-soluble azo polymerization initiator is used, the pH in the polymerization system decreases due to the reaction of the polymerization initiator There are few cases, so the aggregation of particles or the generation of coarse particles caused by the decrease of the dispersibility in the polymerization system can be suppressed.

The conductivity of an aqueous dispersion of resin particles obtained by polymerization using a water-soluble azo-based polymerization initiator dispersed in distilled water is comparable to that of a polymerization initiator other than the water-soluble azo-based polymerization initiator. Compared with the situation, the increase in conductivity of the aqueous dispersion produced by the residue of the polymerization initiator is small. Therefore, the conductivity of the aqueous dispersion of the resin fine particles of the present invention by dispersing 1 part by mass of the resin fine particles in 20 parts by mass of distilled water is 1 to 200 μS/cm, preferably 1 to 100 μS/cm. By setting the conductivity within this range, the transparency of the film can be maintained when the resin fine particles are added.

<Other optional ingredients>

When the resin microparticles of the present invention are produced by emulsion polymerization, a chain transfer agent can be added to the polymerization system. The chain transfer agent to be added includes, for example, mercaptans such as n-octyl mercaptan, tertiary octyl mercaptan, n-dodecyl mercaptan, tertiary-dodecyl mercaptan, and n-hexyl mercaptan; γ -Terpene such as γ-terpinene and dipentene; halogenated hydrocarbons such as chloroform, carbon tetrachloride, methylene chloride, and dibromomethane; α -methylstyrene dimer ; 2,6-Di-tert-butyl-4-methylphenol, styrenated phenol and other phenolic compounds; allyl alcohol and other allyl compounds, etc. The amount of the chain transfer agent used in the present invention is not particularly limited. It is preferably used in the range of 0.1 to 5 parts by mass, and more preferably in the range of 0.1 to 5 parts by mass relative to 100 parts by mass of the total amount of all monomers used in the above-mentioned polymerization. Use in the range of 0.3 to 3 parts by mass.

In the present invention, polymerization initiators other than water-soluble polymerization initiators may also be used. Such polymerization initiators include, for example, cumene hydroperoxide, di-tert-butyl peroxide, dicumyl peroxide, benzyl peroxide, laurel peroxide, dimethyl bis (the first Tributyl peroxy) hexane, dimethyl bis (tertiary butyl peroxy) hexyne-3, bis (tertiary butyl peroxy isopropyl) benzene, bis (tertiary butyl peroxy) Oxy)trimethylcyclohexane, butyl-bis(tert-butylperoxy)valerate, 2-ethylhexane peroxyacid tert-butyl ester, dibenzyl peroxide, hydroperoxide Organic peroxides such as p-menthane and tert-butyl peroxybenzoate; 2,2'-azobisisobutyronitrile (2,2'-azobis(2-methyl-butyronitrile) , 2,2'-azobis(2-isopropylbutyronitrile), 2,2'-azobis(2,3-dimethylbutyronitrile), 2,2'-azobis(2, 4-dimethylbutyronitrile), 2,2'-azobis(2-methylcapronitrile), 2,2'-azobis(2,3,3-trimethylbutyronitrile), 2, 2'-azobis(2,4,4-trimethylvaleronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2 ,4-Dimethyl-4-ethoxyvaleronitrile), 2,2'-azobis(2,4-dimethyl-4-n-butoxyvaleronitrile), 2,2'-azo Bis(4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis[N-(2-propenyl)-2-methylpropanamide], 2,2' -Azobis(N-butyl-2-methylpropanamide), 2,2'-azobis(N-cyclohexyl-2-methylpropanamide), 1,1-azobis( 1-acetoxy-1-phenylethane), 1,1'-azobis(cyclohexane-1-carbonitrile), dimethyl-2,2'-azobis(2-methyl Methyl propionate), dimethyl-2,2'-azobisisobutyrate, 2-(aminomethanoylazo)isobutyronitrile and other azo compounds.

In addition, a redox-based initiator can also be used as a polymerization initiator. The redox-based initiator can be a combination of the following: a combination of the aforementioned persulfate and organic peroxide polymerization initiators, and formaldehyde Reduction of sodium sulfate, sodium bisulfite, ammonium bisulfite, sodium thiosulfate, ammonium thiosulfate, hydrogen peroxide, sodium hydroxymethanesulfinate, L-ascorbic acid and its salts, cuprous salts, ferrous salts, etc. A combination of agents.

Only one type of these polymerization initiators may be used, or two or more types may be mixed and used. In addition, relative to 100 parts by mass of the vinyl monomer, the polymerization initiator is preferably 0.1 to 2 parts by mass, more preferably 0.2 to 1 part by mass, and still more preferably 0.3 to 0.8 parts by mass Use within the scope.

In addition, for the purpose of improving the heat resistance of the resin fine particles, etc., antioxidants such as hindered phenol-based antioxidants and phosphorus-based antioxidants may be added to the above-mentioned polymerization system. Examples of hindered phenol antioxidants include: neopentylerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (trade name: Irganox (registered trademark) 1010), phenylpropionic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy, C7-C9 side chain alkyl ester, 3,3',3”,5,5',5 "-Hexa-tertiary butyl-a,a',a"-(mesitylene-2,4,6-tolyl) tri-p-cresol, diethyl bis[[[3,5-bis( 1,1-Dimethylethyl)-4-hydroxyphenyl)methyl)phosphonate)calcium, octadecyl-3-(3,5-tert-butyl-4-hydroxyphenyl)propionic acid Esters, etc. Phosphorus antioxidants include: tris(2,4-di-tert-butylphenyl) phosphite, tris[2-[[2,4,8,10-tetra-tert-butyl Dibenzo[d,f][1,3,2]dioxaphosphoran-6-yl]oxy]ethyl]amine, bis(2,4-di-tert-butylphenyl) ) Neopentylerythritol diphosphite, bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl phosphite, etc.

[Anti-sticking agent]

The anti-sticking agent of the present invention contains the above-mentioned resin fine particles, and by being contained in the film to impart unevenness to the surface of the film, the slipperiness of the film can be improved, or the film can be prevented from contacting each other and becoming difficult to peel off. sticky).

The film containing the anti-sticking agent of the present invention is not particularly limited. In addition, even when the resin microparticles of the present invention are added to a film containing a cycloolefin resin, they can impart an anti-sticking effect while maintaining the transparency of the film, so they can be suitably used as a film of cycloolefin resin. Anti-sticking agent.

The anti-sticking agent of the present invention can be contained in the film by mixing with the resin constituting the film and forming a film. In addition, a resin composition containing the anti-sticking agent may be coated on the surface of the film.

When the resin fine particles of the present invention are added to a high refractive index film such as a cycloolefin-based film, it can impart an anti-sticking effect while maintaining the transparency of the film.

The material of the film includes, for example, polyolefin resins such as poly-4-methylpentene-1 and polybutene-1, cyclic olefins, polyethylene terephthalate, polyethylene naphthalate, and other polyolefin resins. Ester resin; polycarbonate resin, polyvinyl chloride resin, polyphenylene sulfide resin, polyether sulfide resin, etc. Among these, cycloolefin resins are particularly excellent in heat resistance, moisture absorption resistance, and transparency, and are therefore preferably used as optical members.

[Resin composition]

The resin composition of the present invention contains the aforementioned resin fine particles of the present invention and a resin binder. The resin composition of the present invention can be formed into a molded body using conventional molding methods such as extrusion molding and injection molding, and a solvent may be added as necessary to form a coating agent.

〈Resin Adhesive〉

The resin binder is appropriately selected in accordance with the required characteristics such as transparency, resin particle dispersion, light resistance, moisture resistance, and heat resistance, and is not particularly limited.

For example, one or more resin binders selected from the group consisting of cycloolefin resins, (meth)acrylic resins, (meth)acrylic-urethane resins, urethanes ( urethane) resin, polyvinyl chloride resin, polyvinylidene chloride resin, melamine resin, styrene resin, alkyd resin, phenol resin, epoxy resin, polyester resin, silicone Silicone resins such as alkane resins, (meth)acrylic-polysiloxane resins, polysiloxane-alkyd resins, polysiloxane-urethane resins, polysiloxane-polyester resins Fluorine resins such as modified silicone resins, polyvinylidene fluoride, fluoroolefin vinyl ether polymers, etc.

From the viewpoint of improving the durability of the resin composition, the resin binder may be a curable resin capable of forming a cross-linked structure through a cross-linking reaction. Curable resins can be cured under various curing conditions, and ionizing radiation-curable resins such as thermosetting resins, photo-curable resins, ultraviolet-curable resins, and electron beam-curable resins, heating-curable resins, etc. can be used.

The thermosetting resin may be one or more selected from the group consisting of: a thermosetting urethane resin composed of acrylic polyol and isocyanate prepolymer, phenol resin, urea melamine resin, epoxy Resin, unsaturated polyester resin, silicone resin, etc.

Examples of ionizing radiation curable resins include one or more selected from the group consisting of: polyfunctional (meth)acrylate resins such as polyfunctional (meth)acrylic polyol esters; and diisocyanates , Polyols and (meth)acrylates with hydroxyl groups and other synthetic polyfunctional amine ester acrylate resins.

The ionizing radiation curable resin preferably contains a polyfunctional (meth)acrylate resin, and more preferably contains a polyfunctional (meth)acrylic polyol having 3 or more (meth)acrylic groups in a molecule ester. The polyfunctional (meth)acrylic polyol esters having 3 or more (meth)acrylic groups in one molecule include, for example, one or more selected from the group consisting of: tris(methyl) ) Trimethylolpropane acrylate, trimethylolethane tri(meth)acrylate, 1,2,4-cyclohexane tri(meth)acrylate, pentaglyceryl tri(meth)acrylate, Neopentyl erythritol tetra (meth)acrylate, neopentyl erythritol tri (meth) acrylate, dine pentaerythritol tri (meth) acrylate, dine pentaerythritol penta (meth) acrylate, Dineopentylene erythritol tetra (meth)acrylate, dineopentyl erythritol hexa (meth) acrylate, trine pentaerythritol tri (meth) acrylate, trine pentaerythritol hexa (meth) acrylate Ester etc.

For ionizing radiation curable resins, in addition to these, one or more selected from the group consisting of: polyether resins with acrylate functional groups, polyester resins Grease, epoxy resin, alkyd resin, spiroacetal resin, polybutadiene resin, polythiol polyene resin, etc.

As for the resin binder, in addition to the curable resin, it may also contain a thermoplastic resin. The thermoplastic resin may include at least one selected from the group consisting of: acetyl cellulose, nitro cellulose, acetyl butyl cellulose, ethyl cellulose, methyl cellulose, and other fibers Derivatives; vinyl acetate homopolymers and copolymers, vinyl chloride homopolymers and copolymers, vinylidene chloride homopolymers and copolymers and other vinyl resins; polyvinyl formal, polyethylene Acetal resins such as butyral; (meth)acrylic resins such as homopolymers and copolymers of acrylates, homopolymers and copolymers of methacrylates; polystyrene resins, polyamide resins, thread Polyester resin, polycarbonate resin, etc.

The resin adhesive can also use rubber-based adhesives such as synthetic rubber or natural rubber, or inorganic-based adhesives. The rubber-based binder resin may include one or more selected from the group consisting of ethylene-propylene copolymer rubber, polybutadiene rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, and the like.

Examples of the inorganic binder include one or more selected from the group consisting of silica sol, alkali silicate, silicon alkoxide, and phosphate. The inorganic binder can also be an inorganic or organic-inorganic composite matrix obtained by hydrolyzing and dehydrating and condensing metal alkoxides or silicon alkoxides. As the inorganic or organic-inorganic composite matrix, a silica matrix obtained by hydrolysis and dehydration condensation of a silicon alkoxide (for example, tetraethoxysilane) or the like can be used.

In the ionizing radiation curable resin, when a photocurable resin or an ultraviolet curable resin is used, a photopolymerization initiator can be added to the resin binder.

Any photopolymerization initiator can be used, but it is preferable to use one that is suitable for the photocurable resin or ultraviolet curable resin used.

For example, the photopolymerization initiator can be one or more selected from the group consisting of acetophenones, benzoin, benzophenones, and phosphine oxides. , Ketals, α -hydroxyalkyl phenones, α-aminoalkyl phenones, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3 -Dialkyl diketone compounds, disulfide compounds, fluoroamine compounds, aromatic sulfoniums, onium salts, borate salts, active halogen compounds, α -oxime esters, etc.

Relative to 100% by weight of the binder, the amount of the photopolymerization initiator is usually in the range of 0.5 to 20% by weight, preferably in the range of 1 to 5% by weight.

In the present invention, it is particularly preferable to use cycloolefin resin as the resin binder.

Cycloolefin resin is a polymer having an alicyclic structure in its structural unit. Cycloolefin resins are polymers with alicyclic structures in the main chain, polymers with alicyclic structures in the side chains, polymers with alicyclic structures in the main chain and side chains, and mixed in any ratio A mixture of two or more of these. Among them, from the viewpoint of mechanical strength and heat resistance, a polymer having an alicyclic structure in the main chain is preferred.

Examples of the alicyclic structure include a saturated alicyclic hydrocarbon (cycloalkane) structure and an unsaturated alicyclic hydrocarbon (cycloalkene, cycloalkyne) structure. Among them, from the viewpoint of mechanical strength and heat resistance, a cycloalkane structure and a cycloalkene structure are preferable, and a cycloalkane structure is particularly preferable.

The number of carbons constituting the alicyclic structure is preferably 4 or more in each alicyclic structure, more preferably 5 or more, particularly preferably 6 or more, preferably 30 or less, more preferably 20 Less than, particularly preferably less than 15. When the number of carbons constituting the alicyclic structure is within this range, the mechanical strength, heat resistance, and moldability of the optical member are well balanced.

In the cycloolefin resin, the ratio of the structural unit having an alicyclic structure is preferably 50% by weight or more, more preferably 70% by weight or more, and particularly preferably 90% by weight or more. When the ratio of the structural unit having an alicyclic structure in the cycloolefin resin is within this range, the transparency and heat resistance of the optical member will be good.

Specific examples of cycloolefin-based resins include norbornene-based polymers, monocyclic cyclic olefin polymers, cyclic conjugated diene polymers, vinyl alicyclic hydrocarbon polymers, and hydrogenation of these polymers. Things. Among these, from the viewpoint of transparency and moldability, norbornene-based polymers and hydrogenated products thereof are more preferable.

Examples of the norbornene-based polymer include: a ring-opening polymer of a monomer having a norbornene structure and its hydrogenated product; an addition polymer of a monomer having a norbornene structure and its hydrogenated product. In addition, examples of the ring-opening polymer of a monomer having a norbornene structure include: a ring-opening homopolymer of one monomer having a norbornene structure, and two or more monomers having a norbornene structure The ring-opening copolymer of, as well as the ring-opening copolymer of monomers with norbornene structure and any monomer that can be copolymerized with it. Furthermore, examples of the addition polymer of a monomer having a norbornene structure include: an addition homopolymer of one monomer having a norbornene structure, and two or more monomers having a norbornene structure. Addition copolymers of monomers, and addition copolymers of monomers with norbornene structure and any monomers that can be copolymerized with them. Examples of these polymers include those disclosed in JP 2002-321302 A and the like. Among these, from the viewpoints of transparency, moldability, heat resistance, low moisture absorption, dimensional stability, and light weight, it is particularly suitable as a hydrogenated product of a ring-opening polymer of a monomer having a norbornene structure . Suitable specific examples of norbornene-based polymers include "Zeonor" manufactured by Zeon Japan Co., Ltd.; "Arton" manufactured by JSR Co., Ltd.; "TOPAS" manufactured by TOPAS ADVANCED POLYMERS, etc.

The number average molecular weight of the cycloolefin resin is 10,000 to 200,000, preferably 15,000 to 100,000, more preferably 20,000 to 50,000 based on the polystyrene conversion value measured by the GPC (Gel Permeation Chromatography) method using toluene solvent . In addition, the glass transition temperature of the cycloolefin resin is preferably 80°C or higher, more preferably 100 to 250°C.

The amount of resin fine particles in the resin composition is 2 parts by mass or more, preferably 4 parts by mass or more, and more preferably 6 parts by mass or more with respect to 100 parts by mass of the solid content of the resin binder. By setting it as 6 parts by mass or more, fusion or sticking of the resin composition can be prevented.

The amount of resin fine particles in the resin composition is 300 parts by mass or less, preferably 200 parts by mass or less, and more preferably 100 parts by mass or less with respect to 100 parts by mass of the solid content of the adhesive. By setting it as 300 parts by mass or less, it becomes easy to make the linear penetration of the coating film formed from the resin composition for coating sufficient.

The resin composition may contain an organic solvent as needed. Particularly, when the resin composition is used as a coating agent and applied to a substrate, etc., by containing an organic solvent, it can be easily applied. For example, the organic solvent may be one or more selected from the group consisting of: aromatic solvents such as toluene and xylene; methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, Alcohol solvents such as propylene glycol monomethyl ether; ester solvents such as ethyl acetate and butyl acetate; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, and cyclohexanone; 2 -Methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, propylene glycol methyl ether, etc. Glycol ethers; 2-methoxy ethyl acetate, 2-ethoxy ethyl acetate (ie, ethyl cellosolve acetate), 2-butoxy ethyl acetate, propylene glycol methyl ether ethyl Glycol ether esters such as acid esters; chlorine-based solvents such as chloroform, dichloromethane, chloroform, and methyl chloride; tetrahydrofuran, diethyl ether, 1,4-diorane (1,4-diorane), 1 ,3-dioxolane (1,3-dioxolane) and other ether solvents; N-methyl pyrrolidone (N-methyl pyrrolidone), two Amine-based solvents such as methyl formamide, dimethyl sulfide, and dimethyl acetamide. The amount of the organic solvent can be arbitrarily set in consideration of the coatability of the coating agent and the like.

[Optical components]

The optical member of the present invention contains the resin fine particles of the present invention and resin.

The optical member includes: an optical member formed by molding the resin composition into a film shape, or obtained by coating the resin composition on a film substrate to form a coating film on the film substrate The optical components and so on.

Examples of the optical member include retardation films or diffusion films, anti-glare films, and polarizing plates used in display panels.

The optical member of the present invention preferably contains the resin fine particles of the present invention and a cycloolefin resin. The optical member includes: an optical member formed by molding the resin composition into a film shape, or obtained by coating the resin composition on a film substrate to form a coating film on the film substrate The optical components and so on.

The substrate is preferably transparent. For transparent substrates, for example, the following can be used as substrates: glass, polyethylene terephthalate (PET), polyester-based polymers such as polyethylene naphthalate, and diacetyl Cellulosic polymers such as cellulose and triacetyl cellulose (TAC), polycarbonate polymers, (meth)acrylic polymers such as polymethyl methacrylate, polystyrene, acrylonitrile-benzene Styrenic polymers such as ethylene copolymers, polyethylene, polypropylene, cyclic or norbornene structure polyolefins, olefin polymers such as ethylene-propylene copolymers, vinyl chloride polymers, nylon or aromatic polyolefins Amide-based polymers such as amides, polyimide-based polymers, polyether-based polymers, polyether-based polymers, polyetheretherketone-based polymers, polyphenylene sulfide-based polymers, and vinyl alcohol-based polymerizations Compounds, vinylidene chloride polymers, vinyl butyral polymers, An arylate polymer, a polyoxymethylene polymer, an epoxy polymer, a mixture containing at least one of these polymers, a laminate of these polymers, and the like. Among these, those with a small birefringence are particularly suitable.

Furthermore, (meth)acrylic resins, copolymerized polyester resins, polyurethane resins, styrene-maleic acid grafted polyester resins, acrylic grafts may be provided on at least one surface of these substrates. Easy-adhesive layers such as branched polyester resins are used as substrates.

The thickness of the base material can be appropriately determined, but in general, it is in the range of 10 to 500 μm from the viewpoint of workability such as strength and handling properties, and thin layer properties. Preferably, it can be set to 20 to 300 μm , and more preferably, it can be set to 30 to 200 μm .

The substrate may contain additives. Examples of additives include ultraviolet absorbers, infrared absorbers, antistatic agents, refractive index modifiers, and reinforcing agents.

The method of coating the resin composition on the substrate is not particularly limited. For example, it can be used: bar coating, blade coating, spin coating, reverse coating, die coating, spray coating, roll coating, gravure coating, micro gravure coating, lip coating, air knife coating , Dip coating method and other conventional coating methods.

The thickness (dry thickness) of the layer of the resin composition is not particularly limited, and can be appropriately determined according to the particle size of the resin fine particles. For example, it can be set to 1 to 10 μm , preferably 3 to 7 μm .

The molding method of the above-mentioned film is not particularly limited, and injection molding, melt extrusion, hot pressing, solvent casting (solution flow casting), stretching, etc., which are general molding methods of thermoplastic resins, can be used.

For example, the solution flow casting method described in JP 2017-88715 A is relatively simple. Good solvents for dissolving cycloolefin resins include: chain aliphatic hydrocarbon solvents such as n-pentane and n-hexane; alicyclic hydrocarbon solvents such as cyclopentane and cyclohexane; aromatics such as benzene and toluene Group hydrocarbon solvents; nitrogen-containing hydrocarbon solvents such as nitromethane, nitrobenzene, and acetonitrile; ester solvents such as ethyl acetate; ketone solvents such as acetone; ether solvents such as diethyl ether and the like. These solvents may be used individually by 1 type, and may be used in combination of 2 or more types suitably. Among them, toluene can dissolve a variety of cycloolefin resins, and can be dispersed in the film by dispersing resin particles in toluene.

In addition, Japanese Patent Application Publication No. 2018-30118 describes that when a cycloolefin and the above-mentioned solvent are used to prepare a coating liquid, in addition to the good solvent of the cycloolefin, an alcohol or the like is also added as a poor solvent to make the polymer molecules The degree of entanglement becomes larger and the toughness of the film is improved. In the present invention, a poor solvent may be added within a range that does not hinder the dispersibility of the resin fine particles.

In the optical member of the present invention, the film thickness of the film containing the resin fine particles of the present invention (the film thickness of the optical member formed by molding the resin composition into a film, or by applying the resin composition to the film The thickness of the coating film formed on the substrate is preferably 10 μm or more and 200 μm or less, more preferably 20 μm or more and 100 μm or less. By setting it to 10 μm or more, it becomes easy to prevent the strength of the film from being reduced or breakage after drying. In addition, by setting it to 200 μm or less, it becomes easy to maintain the transparency of the film.

From the standpoint of maintaining the adhesion resistance imparted to the film and the transparency of the film, the content of the resin microparticles in the resin composition of the present invention is preferably 0.05 to 20 parts by mass, more preferably 0.1 to 10 parts by mass.

When an optical member is obtained by coating the above-mentioned resin composition on a film base material to form a coating film on this film base material, the film base material is preferably transparent. Examples of transparent film substrates include polyester polymers such as polyethylene terephthalate (PET) and polyethylene naphthalate, diacetyl cellulose, and triacetyl fibers. A film composed of cellulose polymers such as TAC, polycarbonate polymers, and (meth)acrylic polymers such as polymethyl methacrylate. In addition, transparent film substrates can also be exemplified by styrene polymers such as polystyrene, acrylonitrile-styrene copolymer, polyethylene, polypropylene, cyclic or norbornene structure polyolefins, ethylene -Olefin-based polymers such as propylene copolymers, chlorine A film composed of polymers such as ethylene-based polymers, nylon or amide-based polymers such as aromatic polyamides. Furthermore, transparent film substrates can also be exemplified by: imine polymers, turbid polymers, polyether sulfide polymers, polyether ether ketone polymers, polyphenylene sulfide polymers, ethylene Alcohol-based polymers, vinylidene chloride-based polymers, vinyl butyral-based polymers, arylate-based polymers, polyoxymethylene-based polymers, epoxy-based polymers, or blends of the above-mentioned polymers, etc. The formed film, etc. The above-mentioned film substrate can be particularly suitably used with a small birefringence.

The thickness of the above-mentioned film base material can be appropriately determined, but in general, it is in the range of 10 to 500 μm , preferably 20 to 300 μm from the viewpoints of workability such as strength and handling properties, and thin layer properties. Within the range of m, more preferably within the range of 30 to 200 μm .

In addition, additives can be added to the film substrate. Examples of the above-mentioned additives include ultraviolet absorbers, infrared absorbers, antistatic agents, refractive index modifiers, and reinforcing agents.

In the optical member of the present invention, the content of residual volatile components is preferably 0.1% by mass or less, more preferably 0.05% by mass or less, and still more preferably 0.02% by mass or less. By setting the content of the residual volatile components within the above range, the dimensional stability can be improved, and the change in the optical characteristics caused by the time change can be reduced.

[Resin molded body]

The resin fine particles of the present invention can be used alone or mixed with other resins, and can be formed into resin molded bodies by various molding methods. It is preferable to use a transparent resin for other resins, and by containing resin fine particles, fusion or sticking on the surface of the resin molded body can be prevented.

The resin system can be selected from cycloolefin resins, (meth)acrylic resins, polycarbonate resins, polystyrene resins, (meth)acrylic-styrene resins (that is, (meth)acrylates and One or more of the group consisting of copolymers of styrene). Among these, cycloolefin resin, polystyrene resin, or (meth)acrylic-styrene resin is preferred, and cycloolefin resin is particularly preferred.

When a resin molded body is prepared from the resin microparticles of the present invention and a transparent resin, the amount of the resin microparticles contained in the resin molded body can be in the range of 0.01 to 5 parts by mass relative to 100 parts by mass of the transparent resin, preferably 0.1 To the range of 5 parts by mass. The resin molded body may contain additives such as ultraviolet absorbers, antioxidants, heat stabilizers, light stabilizers, fluorescent whitening agents, etc., as necessary.

The thickness and shape of the resin molded body can be appropriately selected depending on the application.

The resin molded body can be obtained by mixing the above-mentioned resin and the above-mentioned resin fine particles with a mixer, and performing melt-kneading with a uniaxial extruder, a biaxial extruder, or the like. In addition, a T mold and a roll unit may be used to shape the resin composition obtained by melt kneading into a plate shape to obtain a resin molded body. Furthermore, the resin composition obtained by melt kneading may be pelletized, and the pellets may be molded by extrusion molding, injection molding, compression molding, or the like to obtain a resin molded body. Furthermore, it is also possible to form a resin molded body by the molding method described in [Optical member] (injection molding, melt extrusion, hot pressing, solvent casting (solution flow casting), stretching, etc.).

The resin molded body containing the resin microparticles of the present invention has excellent dispersion uniformity of the resin microparticles, and can maintain the color or transparency of the molded body while also imparting anti-sticking properties.

[Example]

The following examples and comparative examples illustrate the present invention, but the present invention is not limited thereto.

For the obtained resin particles, the average primary particle size, the conductivity of the water dispersion of the resin particles, the volume average particle size of the resin particles in toluene, the value A, and the coefficient of variation were determined by the following methods.

In addition, the dispersion stability, anti-sticking property, and film transparency during polymerization were evaluated as follows.

<Average primary particle size>

The average primary particle size of the resin fine particles was measured by a laser diffraction scattering particle size distribution measuring device "LS 230" manufactured by Beckman Coulter Co., Ltd. Specifically, 0.1 g of fine resin particles were weighed into a 100 mL resin cup, and 0.1% by mass of nonionic surfactant (monolauric acid polyoxyethylene sorbitan (ethylene oxide added to moles) Number 20), brand name "Rheodol TW-L120", Kao Co., Ltd.) 50mL of an aqueous solution was added to the aforementioned particles to be measured, and ultrasonic dispersion machine "BRANSON SONIFIER 450" manufactured by BRANSON was used (output 400W, frequency 20kHz), The mixture of water and resin fine particle aggregates was irradiated with ultrasonic waves for 10 minutes to obtain a resin fine particle aggregate dispersion. A laser diffraction scattering particle size distribution measuring device "LS 230" manufactured by Beckman Coulter Co., Ltd. was used to measure the volume average particle size D2 and volume of the particles contained in the resin fine particle aggregate dispersion obtained here. Baseline particle size distribution. In addition, the estimated value of the refractive index of the resin fine particles is input to the laser diffraction scattering particle size distribution measuring device, and an optical model corresponding to the refractive index of the resin fine particles is used to perform data analysis of the laser diffraction scattering particle size distribution measuring device.

<Conductivity of water dispersion of resin particles>

To 1 part by mass of the resin fine particles, 20 parts by mass of distilled water were added, and an ultrasonic cleaner (VS-150 manufactured by AS ONE Co., Ltd.) was used to sufficiently disperse the particles until the powder did not float on the water surface. A conductivity meter ("LAQUAtwin" manufactured by Horiba Manufacturing Co., Ltd.) was used to measure the conductivity of the obtained aqueous dispersion.

<Volume average particle size of resin particles in toluene>

Put 1 part by mass of resin particles and 50 parts by mass of toluene into a 100 mL disposable container with a lid. Formula) AR-100 (trade name: AWATORI RENTARO AR-100 (THINKYMIXER (Non Vacuum) AR-100))) was stirred for 3 minutes, and a dynamic light scattering method was used to measure the thickness of the nanometer particle size distribution (CORDOUAN TECHNOLOGIES) "VASCO") to measure the volume average particle size of the resin particles. The measurement conditions and measurement procedures are as follows.

-Measurement conditions-

‧Dispersion medium: toluene (refractive index 1.490)

‧Measuring temperature: 20℃

‧Statistical mode

-Time limit timestep (timelimit timestep): 60 seconds × 3 times

‧Laser power: 35%

In addition, the analysis method is to select a cumulant, and set the obtained Z-average as the volume average particle size of the resin particles in toluene.

<Value A>

The value A is calculated based on the following formula (1) using the average primary particle size of the resin fine particles and the volume average particle size of the resin fine particles in toluene.

A=(Volume average particle size of resin particles in toluene ÷ average primary particle size of resin particles)‧‧‧(1)

<Coefficient of Variation>

Regarding the coefficient of variation, the particle size distribution obtained in the measurement using the laser diffraction scattering particle size distribution measuring device is used and calculated according to the following formula (2).

Coefficient of variation = (standard deviation of the particle size distribution based on the volume of the resin particles ÷ volume average particle size of the resin particles) × 100‧‧‧(2)

<Evaluation of dispersion stability during polymerization>

After the polymerization of the resin fine particles, visually observe whether precipitation occurs, and evaluate it based on the following criteria.

○: No precipitation is observed after polymerization

×: precipitation is observed after polymerization

<Transparency of film>

(Making of film)

Using the resin microparticles obtained in Examples 1 to 3 and Comparative Examples 1 to 4, optical components were produced according to the following steps, respectively.

10 parts by mass of resin particles and 100 parts by mass of toluene were added, and a defoaming mixer (rotation/revolution mixer (atmospheric pressure type) manufactured by Thinky Co., Ltd.) AR-100 (trade name: AWATORI RENTARO AR-100 (THINKYMIXER ( Non Vacuum) AR-100))) was stirred and mixed for 5 minutes to obtain a resin fine particle dispersion. The preparation of this resin fine particle dispersion is carried out at normal temperature (20°C).

24 parts by mass of the obtained resin fine particle dispersion, 40 parts by mass of cycloolefin resin ("ZEONEX 330R" manufactured by Zeon Japan Co., Ltd.), and 260 parts by mass of toluene were put into a closed container, and were heated and stirred. Completely dissolve to obtain a coating liquid. In the coating liquid, the content of the resin fine particles is 6.0 parts by mass relative to 100 parts by mass of the cycloolefin resin.

The obtained coating liquid was coated on a PET film (manufactured by Kokuyo Co., Ltd., OHP film, thickness 125 μm ) as a transparent film base material so as to have a thickness of 100 μm by a bar coating method. The applied coating solution was dried in an oven at 60° C. for 10 minutes to obtain a film containing resin particles.

(Assessment of transparency)

With respect to the film obtained as described above and having a content of resin fine particles of 6.0 parts by mass relative to 100 parts by mass of cycloolefin resin, the transparency was observed visually, and evaluated based on the following criteria.

○: No white lines or white spots are observed (the best one is ◎)

×: White lines or white spots are observed

〈Adhesion resistance〉

Regarding the film obtained as described above in which the content of fine resin particles is 6.0 parts by mass relative to 100 parts by mass of the cycloolefin resin, the coated surfaces of the films are pressed with fingers and run in at the same time 10 times, and the presence or absence of jams is confirmed live.

○: No jamming or chipping of the film is observed (the best one is ◎)

×: Jamming or chipping of the film occurs

[Example 1]

3600 parts by mass of water as an aqueous medium and polyoxyethylene-1-(allyloxymethyl) alkyl ether sulfate ammonium as a reactive anionic surfactant (manufactured by Daiichi Industrial Pharmaceutical Co., Ltd.) "Aqualon KH-1025") 4.8 parts by mass was supplied into a 5L autoclave equipped with a mixer and a thermometer. Then, 240 parts by mass of methyl methacrylate ("Acryester M" manufactured by Mitsubishi Chemical Co., Ltd.) prepared in advance as a monofunctional vinyl monomer was used as having one or more aromatic rings in the molecule and one 80 parts by mass of benzyl methacrylate ("Light Ester BZ" manufactured by Kyoeisha Chemical Co., Ltd.) as a monofunctional ester-based monomer of an ethylenically unsaturated group, and an ethylene having two or more in the molecule A mixture of 80 parts by mass of ethylene glycol dimethacrylate ("Light Ester EG-50" manufactured by Kyoeisha Chemical Co., Ltd.), a polyfunctional monomer with a sexually unsaturated group, was put into the autoclave, and the autoclave The interior was replaced with nitrogen and the contents of the autoclave were heated to 75°C while stirring. Next, the inner temperature of the autoclave was maintained at 75°C, and the 2,2'-azobis [2-Methyl-N-(2-hydroxyethyl)propanamide] ("VA-086" manufactured by Fujifilm Wako Pure Chemical Co., Ltd.) 2 parts by mass was added to the contents of the autoclave, followed by 6 hours Of aggregation. Then, the inner temperature of the autoclave was increased to 85°C, and the reaction was further carried out for 6 hours to obtain a slurry containing resin fine particles. The solid content concentration of the obtained slurry containing resin fine particles was 10% by weight.

The obtained slurry is classified by a sieve with a pore size of 32 μm to remove coarse particles, and then the spray dryer is used to set the air supply temperature (the temperature of the slurry inlet of the spray dryer) at 180°C and the exhaust temperature (the spray dryer) The temperature of the powder outlet) was spray-dried at 60°C to obtain dried resin particles.

[Example 2]

In Example 1, polyoxyethylene-1-(allyloxymethyl) alkyl ether sulfate ammonium was changed to polyoxyethylene styrenated propenylbenzene as a reactive anionic surfactant Ammonium ether sulfate ("Aqualon AR-1025" manufactured by Daiichi Industrial Pharmaceutical Co., Ltd.) 3.2 parts by mass and polyoxyethylene styrenated allyl phenyl ether as a reactive nonionic surfactant (the first Except that "Aqualon AN-5065" manufactured by Industrial Pharmaceutical Co., Ltd.) 0.3 parts by mass, other systems were the same as in Example 1 to prepare resin microparticles. The average primary particle size of the obtained resin fine particles was 148 nm.

[Example 3]

In Example 2, ethylene glycol dimethacrylate was changed to trimethylolpropane trimethacrylate (TMPTMA, "Light Ester TMP" manufactured by Kyoeisha Chemical Co., Ltd.). , Other systems were the same as in Example 2 to prepare a slurry of resin fine particles.

After passing the obtained slurry through a sieve with a pore size of 32 μm for classification to remove coarse particles, the spray dryer ("TR 100" manufactured by Preci Co., Ltd.) Spray drying is performed at 180°C and exhaust temperature (temperature at the powder outlet of the spray dryer) at 60°C to obtain dried resin fine particles. The average primary particle size of the obtained resin fine particles was 153 nm.

[Comparative Example 1]

In Example 2, the resin fine particles were produced in the same manner as in Example 2 except that benzyl methacrylate was changed to styrene. After the polymerization, precipitation occurred and uniform particles could not be obtained.

[Comparative Example 2]

In Comparative Example 1, the reactive anionic surfactant "Aqualon AR-1025" was increased to 32 parts by mass, and the reactive nonionic surfactant "Aqualon AN-5065" was increased to 3 parts by mass. Otherwise, the resin fine particles were produced in the same manner as in Comparative Example 1 for other systems. The average primary particle diameter of the obtained resin fine particles was 87 nm.

[Comparative Example 3]

In Example 2, in addition to changing the polymerization initiator from 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propanamide] to ammonium persulfate, other systems In the same manner as in Example 2, resin fine particles were produced. The average primary particle diameter of the obtained resin fine particles was 130 nm.

[Comparative Example 4]

3000 parts by mass of water as an aqueous medium and polyoxyethylene-1-(allyloxymethyl) alkyl ether sulfate ammonium as a reactive anionic surfactant (manufactured by Daiichi Industrial Pharmaceutical Co., Ltd.) "Aqualon KH-1025") 30.8 parts by mass was supplied into a 5L autoclave equipped with a stirrer and a thermometer. Then, 615 parts by mass of methyl methacrylate ("Acryester (registered trademark) M" manufactured by Mitsubishi Chemical Co., Ltd.) prepared in advance as a monofunctional vinyl monomer and allyl methacrylate ( "Acryester A" manufactured by Mitsubishi Gas Chemical Co., Ltd.) 154 parts by mass of the mixture was put into the autoclave, the inside of the autoclave was replaced with nitrogen, and the contents of the autoclave were heated to 70°C while stirring. Next, the inner temperature of the autoclave was kept at 70°C, and ammonium persulfate (Fujifilm Wako Pure Chemical Co., Ltd.) was used as a polymerization initiator. After adding 3.85 parts by mass of APS manufactured to the contents of the autoclave, polymerization was carried out for 1.5 hours. Then, the inner temperature of the autoclave was increased to 80°C, and the reaction was further performed for 1 hour to obtain a slurry containing resin fine particles. The subsequent operation system was the same as in Example 1 to obtain dry resin fine particles. The average primary particle size of the obtained resin fine particles was 102 nm.

Regarding Examples 1 to 3 and Comparative Examples 1 to 4, the monomers used in the polymerization of resin particles, polymerization initiators and their amounts (parts by mass), the average primary particle size of the resin particles obtained, and the resin particles The conductivity of an aqueous dispersion of 1 part by mass of fine particles dispersed in 20 parts by mass of distilled water, the volume average particle size of the resin particles in toluene, the value A, the coefficient of variation, the dispersion stability during polymerization, the transparency of the film, and the The anti-sticking evaluation system is summarized in Table 1.

[Table 1]

In Table 1, the rows from MMA to VA-086 indicate the mass ratios of the compounds used in the production of resin microparticles, and the compounds represented by each abbreviation are as follows.

MMA: methyl methacrylate

BzMA: Benzyl methacrylate

St: Styrene

EGDMA: ethylene glycol dimethacrylate

TMPTMA: Trimethylolpropane Trimethacrylate

AMA: Allyl methacrylate

KH-1025: Polyoxyethylene-1-(allyloxymethyl) alkyl ether ammonium sulfate

AR-1025: Polyoxyethylene styrenated ammonium allyl phenyl ether sulfate

AN-5065: Polyoxyethylene styrenated allyl phenyl ether

APS: Ammonium Persulfate

VA-086: 2,2’-Azobis[2-methyl-N-(2-hydroxyethyl)propanamide]

It can be seen from Table 1 that it contains structural units derived from BzMA (monofunctional ester monomers with more than one aromatic ring and one ethylenically unsaturated group in the molecule) and structural units derived from EGDMA or TMPTMA (with two in the molecule) In Examples 1 to 3 in which the above-mentioned polyfunctional monomer of ethylenically unsaturated group) is the structural unit and the conductivity of the aqueous dispersion is 1 to 200 μS /cm, the dispersion stability during the polymerization of the resin fine particles is excellent, In addition, the adhesion resistance of the optical member containing the resin fine particles and the transparency of the film are excellent.

On the other hand, in the resin fine particles of Comparative Example 1 prepared by changing benzyl methacrylate to styrene, the dispersion stability during polymerization was poor, and agglomerates were generated. In the resin fine particles of Comparative Example 2 in which the amount of reactive surfactant was increased in Comparative Example 1, although the dispersibility during polymerization was good, The film can be coated, but due to its small particle size, it lacks anti-sticking properties, and there are many reactive surfactant residues, which impairs the transparency of the film.

In addition, it can be seen that in Example 2 in which VA-086, which is a water-soluble azo polymerization initiator, was used as the polymerization initiator, the conductivity of the aqueous dispersion was 1 to 200 μS /cm. On the other hand, In Comparative Example 3 in which the polymerization initiator was changed in Example 2 and the water-soluble azo polymerization initiator was not used, the conductivity of the aqueous dispersion exceeded 200 μS /cm. In addition, compared with the optical member containing the resin microparticles of the example, the optical member of the resin microparticles of Comparative Example 3 containing the water dispersion with a conductivity of more than 200 μS /cm is inferior in transparency.

In addition, in Comparative Example 4, when methyl methacrylate and allyl methacrylate were used to produce crosslinked resin particles, although the dispersibility during polymerization was good, the dispersibility in toluene was compared with the particles in the examples. In order to deteriorate significantly, it is difficult to disperse in the film.

[Other implementation types]

In addition, the implementation type system disclosed this time is only an example in terms of all the features, and is not a basis for a limited interpretation. Therefore, the technical scope of the present invention should not be interpreted only by the above-mentioned implementation types, but should be defined according to the description of the scope of the patent application. In addition, the technical scope of the present invention includes all changes within the meaning and scope equivalent to the scope of the patent application.

[Industrial availability]

The present invention can be used as resin fine particles, which can impart an anti-sticking effect when added to various resin films including cycloolefin resin films while maintaining the transparency of the film.

Claims (10)

A resin fine particle that satisfies the following requirements (a) to (c): (a) The resin constituting the resin particles contains: 3 to 95% by mass based on the total structural units, derived from a structure of a monofunctional ester monomer having at least one aromatic ring and one ethylenically unsaturated group in the molecule Units, and 3 to 50% by mass based on the total structural units, of structural units derived from multifunctional monomers having two or more ethylenic unsaturated groups in the molecule; (b) The average primary particle size is 50 to 800 nm; and (c) The conductivity of an aqueous dispersion obtained by dispersing 1 part by mass of resin fine particles in 20 parts by mass of distilled water is 1 to 200 μS /cm. The resin fine particles according to claim 1, wherein the value A represented by the following formula (1) is 0.9 or more and 5.0 or less, A=(Volume average particle size of resin particles in toluene ÷ average primary particle size of resin particles)‧‧‧(1). The resin fine particles according to claim 1 or 2, wherein the coefficient of variation of the average primary particle size represented by the following formula (2) is 25% or less, Coefficient of variation = (standard deviation of the particle size distribution based on the volume of the resin particles ÷ volume average particle size of the resin particles) × 100‧‧‧(2). The resin fine particles according to any one of claims 1 to 3, wherein the monofunctional ester system is selected from benzyl (meth)acrylate, phenyl (meth)acrylate, and benzene (meth)acrylate One or more of the group consisting of oxyethyl ester. A method for producing resin microparticles, which uses at least one water-soluble azo polymerization initiator and emulsifies and polymerizes the following monomer components in an aqueous medium, wherein the monomer components are contained in terms of all monomer components ：3 to 95% by mass has more than one aromatic ring and one in the molecule Monofunctional ester monomers of ethylenically unsaturated groups, and 3 to 50% by mass of multifunctional monomers having 2 or more ethylenic unsaturated groups in the molecule. The method for producing resin fine particles according to claim 5, wherein at least one reactive surfactant having an ethylenically unsaturated group is used during emulsion polymerization. An anti-sticking agent, which is composed of the resin microparticles described in any one of claims 1 to 4. A resin composition comprising: the resin fine particles according to any one of claims 1 to 4, and a resin binder. An optical member comprising: the resin fine particles according to any one of claims 1 to 4. A resin molded body comprising: the resin fine particles according to any one of claims 1 to 4.