JP2019206608A - Polymer dispersant, manufacturing method of polymer dispersant, and filler dispersion - Google Patents

Abstract

To provide a polymer dispersion capable of stably dispersing a filler in a low polarity liquid medium.SOLUTION: There is provided a polymer dispersant which is an acrylic polymer having a carboxyl group at a terminal, which is a reaction product between an acrylic polymer block having one or more hydroxyl group at a terminal thereof, and at least one of succinic acid derivative represented by the general formula (1) and succinic acid anhydride derivative represented by the general formula (2), in which content of a constitutional unit derived from (meth)acrylic acid ester represented by the general formula (3) is 80 mass% or more and number average molecular weight is 2,000 to 12,000. Rrepresents an alkyl group having 4 or more carbon atoms, or the like, Rrepresents a methyl group, or the like, and Rrepresents an alkyl group having 8 to 22 carbon atoms.SELECTED DRAWING: None

Description

  The present invention relates to a polymer dispersant capable of stably dispersing a filler at a high concentration in a low-polar liquid solvent, a method for producing the same, and a filler dispersion using the polymer dispersant.

  A hydrocarbon having 8 or more carbon atoms, an alkanol having 8 or more carbon atoms, an alkenol having 8 or more carbon atoms, a fatty acid having 8 or more carbon atoms, an unsaturated fatty acid having 8 or more carbon atoms, a fatty acid having 8 or more carbon atoms and a hydroxyl group-containing compound. Products using liquid media such as esters, esters of unsaturated fatty acids having 8 or more carbon atoms and hydroxyl group-containing compounds, and silicone oil, cosmetics, liquid toners, oil-based inkjet inks, weak solvent paints, lubricating oils, cleaning agents and so on. Moreover, the function according to a use is provided by disperse | distributing the fillers including a pigment etc. in these liquid media.

  However, since all of the above liquid media have low polarity, it is difficult to stably finely disperse polar fillers such as pigments at a high concentration. For this reason, various proposals have been made for stably dispersing a polar filler in a low-polar liquid medium. For example, a liquid developer containing acidic carbon black, a basic group-containing pigment dispersant, and an acidic pigment derivative has been proposed (Patent Document 1). Further, a liquid developer containing a dispersant for liquid development having a polar chain such as an ether group, toner particles, and a hydrocarbon solvent has been proposed (Patent Document 2). Furthermore, a makeup composition containing a non-volatile hydrocarbon oil, a non-volatile silicone compound, an inert filler, and a hydrocarbon fluid dispersant has been proposed (Patent Document 3).

International Publication No. 2015/119147 JP 2017-173731 A JP 2002-145738 A

  However, even the compositions such as developers proposed in Patent Documents 1 to 3 are not necessarily excellent in the dispersibility of the filler, and there is room for further improvement.

  The present invention has been made in view of such problems of the prior art, and the problem is that a polymer dispersion that can stably disperse a filler in a low-polarity liquid medium. It is to provide an agent. Moreover, the place which makes the subject of this invention the manufacturing method of the said polymer dispersing agent, and the filler obtained using the said polymer dispersing agent were disperse | distributed stably, and the dispersibility of the filler fell. An object of the present invention is to provide a filler dispersion that can be easily redispersed even in such a case.

  As a result of intensive studies to solve the above problems, the present inventors reacted a succinic anhydride derivative containing a long-chain alkyl group or the like with a long-chain alkyl group-containing polymer block having one or more hydroxyl groups at its ends. The present inventors have found that a specific acrylic polymer that is a reaction product is useful, and have completed the present invention.

That is, according to the present invention, the following polymer dispersant is provided.
[1] A polymer dispersant used for dispersing a filler in a low-polarity liquid medium,
Reaction of an acrylic polymer block having one or more hydroxyl groups at its terminal with at least one of a succinic acid derivative represented by the following general formula (1) and a succinic anhydride derivative represented by the following general formula (2) It is an acrylic polymer having a carboxy group at its end, which is a product, and the content of a structural unit derived from a (meth) acrylic acid ester represented by the following general formula (3) is 80% by mass or more, A polymer dispersant having a polystyrene-equivalent number average molecular weight of 2,000 to 12,000 as measured by gel permeation chromatography.

（前記一般式（１）及び（２）中、Ｒ₁は炭素数４以上のアルキル基又はアルケニル基を示す。前記一般式（３）中、Ｒ₂は水素原子又はメチル基を示し、Ｒ₃は炭素数８〜２２のアルキル基を示す）

(In the general formula (1) and (2), R ₁ is in indicates the number 4 or more alkyl or alkenyl group having a carbon. The general formula (3), R ₂ represents a hydrogen atom or a methyl group, R ₃ Represents an alkyl group having 8 to 22 carbon atoms)

Moreover, according to this invention, the manufacturing method of the polymer dispersing agent shown below is provided.
[2] A method for producing a polymer dispersant as described in [1] above, wherein at least one of an azo radical initiator having one or more hydroxyl groups and a chain transfer agent is used in a polymerization solvent, A step of polymerizing a monomer component containing a (meth) acrylic acid ester represented by the formula (3) to obtain an acrylic polymer block having one or more hydroxyl groups at its ends; the acrylic polymer block; And a step of reacting at least one of a succinic acid derivative represented by the formula (1) and a succinic anhydride derivative represented by the following general formula (2).

（前記一般式（１）及び（２）中、Ｒ₁は炭素数４以上のアルキル基又はアルケニル基を示す。前記一般式（３）中、Ｒ₂は水素原子又はメチル基を示し、Ｒ₃は炭素数８〜２２のアルキル基を示す）

(In the general formula (1) and (2), R ₁ is in indicates the number 4 or more alkyl or alkenyl group having a carbon. The general formula (3), R ₂ represents a hydrogen atom or a methyl group, R ₃ Represents an alkyl group having 8 to 22 carbon atoms)

[3] The method for producing a polymer dispersant according to the above [2], wherein the content of the structural unit derived from the (meth) acrylic acid ester in the acrylic polymer block is 90% by mass or more.
[4] The group wherein the polymerization solvent is composed of a hydrocarbon having 8 or more carbon atoms, an alkanol having 8 or more carbon atoms, a fatty acid having 8 or more carbon atoms, an ester of a fatty acid having 8 or more carbon atoms and a hydroxyl group-containing compound, and silicone oil. The method for producing a polymer dispersant according to the above [2] or [3], which is at least one selected from the above.

Furthermore, according to this invention, the manufacturing method of the filler dispersion liquid shown below shown below is provided.
[5] A filler dispersion containing a low-polarity liquid medium, a filler, and a dispersant for dispersing the filler in the liquid medium, wherein the dispersant is the polymer dispersant described in [1]. A filler dispersion.
[6] The filler dispersion according to [5], wherein the filler is at least one selected from the group consisting of titanium dioxide, zinc oxide, iron oxide, and silica.
[7] The liquid medium is a hydrocarbon having 8 or more carbon atoms, an alkanol having 8 or more carbon atoms, an alkenol having 8 or more carbon atoms, a fatty acid having 8 or more carbon atoms, an unsaturated fatty acid having 8 or more carbon atoms, or 8 or more carbon atoms. [5] or [6], which is at least one selected from the group consisting of an ester of a fatty acid and a hydroxyl group-containing compound, an ester of an unsaturated fatty acid having 8 or more carbon atoms and a hydroxyl group-containing compound, and silicone oil. Filler dispersion.
[8] The filler dispersion according to any one of [5] to [7], which contains 3 to 50 parts by mass of the polymer dispersant with respect to 100 parts by mass of the filler.

  ADVANTAGE OF THE INVENTION According to this invention, the polymer dispersing agent which can disperse | distribute a filler stably in a low polar liquid medium can be provided. Moreover, according to this invention, the manufacturing method which can manufacture said polymer dispersing agent simply can be provided.

  Furthermore, according to the present invention, the filler obtained by using the above polymer dispersant is stably dispersed and can be easily redispersed even when the dispersibility of the filler is lowered. Possible filler dispersions can be provided. The filler dispersion liquid of the present invention includes, for example, cosmetics, liquid developers, oil-based inkjet inks, ultraviolet curable inkjet inks, weak solvent-type paints, offset inks, lubricants, cleaning agents, insecticides, release agents, adhesives, and the like. Useful as.

<Polymer dispersant>
Embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments. The polymer dispersant of the present invention is an acrylic polymer having a carboxy group at its end, which is used to disperse a filler in a low polarity liquid medium. The polymer dispersant (acrylic polymer) of the present invention includes an acrylic polymer block having one or more hydroxyl groups at its ends, a succinic acid derivative represented by the following general formula (1), and the following general formula (2). The content of the structural unit derived from the (meth) acrylic acid ester represented by the following general formula (3) is 80% by mass or more. The number average molecular weight in terms of polystyrene measured by gel permeation chromatography is 2,000 to 12,000.

（前記一般式（１）及び（２）中、Ｒ₁は炭素数４以上のアルキル基又はアルケニル基を示す。前記一般式（３）中、Ｒ₂は水素原子又はメチル基を示し、Ｒ₃は炭素数８〜２２のアルキル基を示す）

(In the general formula (1) and (2), R ₁ is in indicates the number 4 or more alkyl or alkenyl group having a carbon. The general formula (3), R ₂ represents a hydrogen atom or a methyl group, R ₃ Represents an alkyl group having 8 to 22 carbon atoms)

  The polymer dispersant of the present invention is an acrylic polymer that can be dissolved in a low-polarity liquid medium, and has a carboxy group at its terminal, preferably one terminal. When the carboxy group is bonded to the filler by hydrogen bonding, ionic bonding, or chemical bonding, the polymer dispersant is adsorbed on the filler, and the filler can be stably dispersed in the low-polarity liquid medium. The carboxy group is formed by reacting a succinic acid derivative or succinic anhydride derivative having a long-chain alkyl group or alkenyl group that can be dissolved in a low-polarity liquid medium with a hydroxyl group of the acrylic polymer block.

  The acrylic polymer block having one or more hydroxyl groups, preferably two or more hydroxyl groups at its end is a hydrophobic polymer block containing a structural unit derived from a (meth) acrylic acid ester represented by the general formula (3). is there. Since the (meth) acrylic acid ester represented by the general formula (3) is a monomer having a long-chain alkyl group, the acrylic polymer block containing a structural unit derived from this (meth) acrylic acid ester is hydrophobic. high. Therefore, the polymer dispersant of the present invention, which is a reaction product obtained by reacting this acrylic polymer block with a predetermined succinic anhydride derivative or the like, has high compatibility and solubility in a low-polar liquid medium. It is suitable as a dispersant for dispersing the filler in such a low-polarity liquid medium.

  Examples of the (meth) acrylic acid ester represented by the general formula (3) include octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, (meth ) Isodecyl acrylate, dodecyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, behenyl (meth) acrylate, and the like. These (meth) acrylic acid esters can be used alone or in combination of two or more.

  In the polymer dispersant, the content of the structural unit derived from the (meth) acrylic acid ester represented by the general formula (3) is 80% by mass or more, and preferably 85% by mass or more. By making content of the structural unit derived from (meth) acrylic acid ester into 80 mass% or more, it can be set as the polymer dispersing agent which can be melt | dissolved in a low polar liquid medium. When the content of the structural unit derived from (meth) acrylic acid ester is less than 80% by mass, it is difficult to dissolve in a low-polarity liquid medium, and it becomes difficult to stably disperse the filler.

Examples of the succinic acid derivative represented by the general formula (1) include butyl succinic acid, pentyl succinic acid, hexyl succinic acid, 2-hexen-1-yl-succinic acid, octyl succinic acid, 2-ethylhexyl succinic acid, decyl succinic acid, Examples include dodecyl succinic acid, isooctadecenyl succinic acid, and octadecyl succinic acid. Moreover, as a succinic anhydride derivative represented by General formula (2), the acid anhydride of said succinic acid derivative can be mentioned. Among these, from the viewpoints of compatibility and solubility in a low polarity liquid medium, R ₁ in the general formulas (1) and (2) is preferably an alkyl group or alkenyl group having 8 or more carbon atoms.

  The number average molecular weight in terms of polystyrene of the polymer dispersant measured by gel permeation chromatography is 2,000 to 12,000, preferably 2,000 to 10,000. When the number average molecular weight is less than 2,000, since the molecular weight is too small, the steric repulsion when the filler is dispersed is not exhibited, and a stable dispersion cannot be obtained. On the other hand, when the number average molecular weight is more than 12,000, the viscosity of the dispersion liquid in which the filler is dispersed becomes excessively high, and the amount of adsorbed parts on the filler is relatively reduced. There is a need.

  The polymer dispersant of the present invention is used to disperse a filler in a low polarity liquid medium. Low polar liquid media include hydrocarbons having 8 or more carbon atoms, alkanols having 8 or more carbon atoms, alkenols having 8 or more carbon atoms, fatty acids having 8 or more carbon atoms, unsaturated fatty acids having 8 or more carbon atoms, and 8 or more carbon atoms. And an ester of a fatty acid and a hydroxyl group-containing compound, an ester of an unsaturated fatty acid having 8 or more carbon atoms and a hydroxyl group-containing compound, and silicone oil. These liquid media can be used singly or in combination of two or more. These liquid media have a very low relative dielectric constant of around 2. Further, the solubility parameter of these liquid media is about 8 or less. For this reason, these liquid media are very low polarity liquid media.

  As hydrocarbons having 8 or more carbon atoms, octane, octene, 2-ethylhexane, nonane, decane, isodecane, dodecane, isododecane, tridecane, undecane, octadecane, C8-20 isoparaffin, squalane, petrolatum, microcrystalline wax, water Polyisobutene, 1-octene, 2-octene, 1-nonene, 2-nonene, 1-decene, 2-decene, 1-undecene, 2-undecene, 1-dodecene, 2-dodecene, 1-tridecene, 2-tridecene 1-tetradecene, 2-tetradecene, 1-pentadecene, 2-pentadecene, 1-hexadecene, 2-hexadecene, 1-heptadecene, 2-heptadecene, 1-octadecene, 2-octadecene dimethylcyclohexane, trimethylcyclohexane, ethyl Rohekisan, propyl cyclohexane, cyclohexanone, and the like.

  As alkanols and alkenols having 8 or more carbon atoms, octanol, 2-ethylhexanol, nonanol, decanol, isodecanol, dodecanol, cetyl alcohol, stearyl alcohol, aralkyl alcohol, behenyl alcohol, hexyl decanol, octyldodecanol, isocetyl alcohol, isostearyl Examples include alcohol and oleyl alcohol.

  Examples of fatty acids having 8 or more carbon atoms and unsaturated fatty acids include octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, tridecanoic acid, stearic acid, oleic acid, 12-hydroxystearic acid, ricinoleic acid, ricinoleic acid, undecylenic acid, isononane Examples include acid, myristic acid, palmitic acid, myristic acid, 2-ethylhexanoic acid and the like.

  Examples of the ester of a fatty acid having 8 or more carbon atoms and a hydroxyl group-containing compound, and the ester of an unsaturated fatty acid having 8 or more carbon atoms and a hydroxyl group-containing compound include methyl laurate, heptyl undecylate, isononyl isononanoate, ethyl oleate, myristine Isopropyl acid, isopropyl palmitate, butyl stearate, cetyl palmitate, myristyl myristate, octyldodecyl myristate, isopropyl isostearate, ethyl isostearate, cetyl 2-ethylhexanoate, hexyl isostearate, ethylene di-2-ethylhexanoate Glycol, dioleic acid ethylene glycol, di (capryl capric acid) propylene glycol, dioleic acid propylene glycol, triisostearic acid trimethylolpropane, tetra -Pentaerystyl ethylhexanoate, neopentyl glycol diheptanoate, isocetyl isostearate, 2-octyldodecyl dimethyloctanoate, myristyl lactate, trioctyldodecyl citrate, diisostearyl malate, di-2-ethylhexyl succinate, adipic acid Examples include diisopropyl, diisobutyl adipate, and cholesteryl stearate fatty acid. Furthermore, oils and fats such as almond oil, avocado oil, olive oil, shea butter, shea butter oil, evening primrose oil, chabodia seed oil, camellia oil, babas oil, peanut oil, rosehip oil, which are triesters with glycerin; And waxes such as owl, jojoba oil, candelilla wax and carnauba wax.

  Silicone oils include dimethyl silicone oil, methylphenyl silicone oil, methyl hydrogen silicone oil, amino modified silicone oil, epoxy modified silicone oil, carboxy modified silicone oil, carbinol modified silicone oil, polyether modified silicone oil, alkyl modified silicone. Examples thereof include oil and fluorine-modified silicone oil.

  As fillers, inorganic pigments, organic pigments, extender pigments, fillers, inorganic fine particles, diamond, graphene, graphite, carbon black, carbon nanotubes, clay, conductive fillers, thermal conductive agents, carbon fibers, glass fibers, cellulose, cellulose Examples include nanofibre. These fillers are particulate, powdery, or fibrous substances that are added to plastics, rubber, paints, inks, and the like in order to improve strength and functionality and reduce costs. As the filler, an inorganic filler that is an inorganic compound is preferably used. More specifically, titanium dioxide which is a white pigment; zinc oxide which is used for sunscreen and the like having ultraviolet reflectivity; iron oxide which is used as a coloring material such as petals, ocher and iron black; transparency and Silica used for strength improvement is preferred. There are no particular restrictions on the crystal form, particle diameter, surface state, presence or absence of surface treatment, and the like of the filler.

<Method for producing polymer dispersant>
The method for producing a polymer dispersant of the present invention uses at least one of an azo radical initiator having one or more hydroxyl groups and a chain transfer agent in a polymerization solvent, and is represented by the general formula (3) (meta ) A step of polymerizing a monomer component containing an acrylate ester to obtain an acrylic polymer block having one or more hydroxyl groups at its ends (step (1)), the obtained acrylic polymer block, and the general formula (1) ) And a step of reacting at least one of the succinic anhydride derivative represented by the general formula (2) (step (2)).

  In the step (1), at least one of an azo radical initiator having one or more hydroxyl groups and a chain transfer agent is used in the polymerization solvent, and the (meth) acrylic acid ester represented by the general formula (3) is included. Polymerize monomer components. By polymerizing using an azo radical initiator having one or more hydroxyl groups or a chain transfer agent, a polymer in which residues derived from these initiators or chain transfer agents are incorporated, that is, one or more at the terminal An acrylic polymer block having a hydroxyl group, preferably two or more hydroxyl groups can be obtained.

  Examples of the azo radical initiator having one or more hydroxyl groups include 2,2′-azobis (2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] propionamide), 2,2 In addition to '-azobis (2-methyl-N- [2- (1-hydroxybutyl)] propionamide), 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 4 , 4′-azobis (4-cyanovaleric acid) and a compound obtained by reacting an epoxy group or a compound having two or more hydroxyl groups.

  Examples of the chain transfer agent having one or more hydroxyl groups include hydroxyethanethiol and thioglycerol, as well as amidated products of thiol group-containing carboxylic acid compounds such as thiomalic acid with ethylene glycol monoester and aminoethanol. Moreover, the initiator compound which has a hydroxyl group used by living radical polymerization can also be used as a chain transfer agent which has one or more hydroxyl groups. Specifically, bis (4- (ethyl- (2-hydroxyethyl) carbamoyl) benzyl) trithiocarbonate, 4-cyano-4-((dodecylsulfanylthio), which is a sulfur compound used for reversible transfer catalytic polymerization. Carbonyl) sulfanyl) pentanoic acid ester; 4-hydroxy-2,2,6,6-tetrapiperidine-1-oxy and the like used in nitroxide thermal dissociation polymerization method; for atom transfer radical polymerization and reversible catalytic transfer polymerization Examples thereof include 2-bromoisobutyric acid ethylene glycol monoester and 2-iodoisobutyric acid ethylene glycol monoester, which are halogen compounds used.

By polymerizing the monomer component containing the (meth) acrylic acid ester represented by the general formula (3) in the presence of the above-mentioned azo radical initiator or chain transfer agent, one or more hydroxyl groups, preferably An acrylic polymer block having two or more hydroxyl groups can be obtained.
In addition, it is preferable that the 2 or more hydroxyl group is introduce | transduced into the terminal of the acrylic polymer block obtained. By forming an acrylic polymer block having two or more hydroxyl groups at its terminal, two or more carboxy groups are added to the terminal of a polymer dispersant (acrylic polymer) obtained by subsequent reaction with a succinic anhydride derivative or the like. It can be introduced, and a polymer dispersing agent with improved adsorption to the filler can be obtained.

  When the above azo radical initiator or chain transfer agent is used, a hydroxyl group is introduced at one or both ends of the resulting acrylic polymer block, but a hydroxyl group may be introduced at one end of the acrylic polymer block. preferable. When an acrylic polymer block having hydroxyl groups at both ends thereof is used, fillers may be connected at both ends of the resulting polymer dispersant and may easily aggregate.

  The content of the structural unit derived from the (meth) acrylic acid ester represented by the general formula (3) in the acrylic polymer block having one or more hydroxyl groups at the terminal is preferably 90% by mass or more. And more preferably 95% by mass or more. Moreover, it is more preferable that the acrylic polymer block is substantially composed only of structural units derived from the (meth) acrylic acid ester represented by the general formula (3). By setting the content of the structural unit derived from the (meth) acrylic ester in the acrylic polymer block to 90% by mass or more, a polymer dispersant that can be dissolved in a low-polar liquid medium can be obtained.

  The acrylic polymer block may include a structural unit (other structural unit) other than the structural unit derived from the (meth) acrylic acid ester represented by the general formula (3). Other monomers constituting the structural unit include carboxy group-containing methacrylic monomers such as (meth) acrylic acid and 2- (meth) acryloyloxyethyl phthalate; methyl (meth) acrylate, ethyl (meth) acrylate, butyl Alkyl (alkenyl) (meth) acrylates such as (meth) acrylate, hexyl (meth) acrylate, and allyl (meth) acrylate; cyclohexyl (meth) acrylate, t-butylcyclohexyl (meth) acrylate, trimethylcyclohexyl (meth) acrylate, isobornyl Cycloalkyl (cycloalkenyl) (meth) acrylate such as (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate; benzyl (meth) acrylate (Meth) acrylate having an aromatic ring such as a rate, phenyl (meth) acrylate; phenoxyethyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) Oxygen atom-containing (meth) acrylates such as acrylate and glycidyl methacrylate; Halogen atom-containing (meth) acrylates such as trifluoroethyl (meth) acrylate and heptadecafluorodecyl (meth) acrylate; Trimethylsilyl (meth) acrylate and polysiloxane (meta ) Silicon atom-containing (meth) acrylates such as acrylate; 2- (4-benzoxy-3-hydroxyphenoxy) ethyl methacrylate, 2- (2′-hydroxy-5-metac) (Meth) acrylate having an ultraviolet absorbing group such as leuoxyethylphenyl) -2H-benzotriazole; nitrogen atom-containing (meth) acrylate such as tetramethylpiperidinyl (meth) acrylate and diethylaminoethyl (meth) acrylate; Can be mentioned. Moreover, the macromonomer etc. which the one terminal is a (meth) acryloyl group etc. can also be used as needed.

  Furthermore, monomers such as a styrene vinyl monomer, an amide monomer, a vinyl alkanoate monomer, and a maleic acid monomer can be used as monomers constituting other structural units.

  Examples of the styrene vinyl monomer include styrene, α-methylstyrene, vinyl toluene, vinyl naphthalene, vinyl biphenyl, vinyl anthracene, and vinyl xylene. Examples of the amide monomer include (meth) acrylamide, dimethyl (meth) acrylamide, (meth) acryloylmorpholine, isopropyl (meth) acrylamide, hydroxyethyl acrylamide, dimethylaminopropyl acrylamide and the like.

  Examples of vinyl alkanoic monomers include vinyl acetate, vinyl propionate, vinyl benzoate, vinyl laurate, vinyl monochloroacetate, vinyl pivalate, and vinyl cyclohexanecarboxylate. Examples of maleic monomers include maleic acid, maleic anhydride, maleic acid monomethyl ester, maleic acid monobutyl ester, and dibutyl maleate.

  As a polymerization solvent, fillers such as hydrocarbons having 8 or more carbon atoms, alkanols having 8 or more carbon atoms, fatty acids having 8 or more carbon atoms, esters of fatty acids having 8 or more carbon atoms and a hydroxyl group-containing compound, and silicone oil are dispersed. It is preferable to use a low-polarity solvent similar to the liquid medium described above. These polymerization solvents can be used alone or in combination of two or more. A material for producing a filler dispersion without separating or purifying the synthesized polymer dispersant by using a substantially the same type of solvent as the polymerization solvent as the low-polarity liquid medium in which the filler is dispersed. Is preferable because it can be used as it is.

  In the step (2), the acrylic polymer block obtained in the step (1) and at least one of the succinic acid derivative represented by the general formula (1) and the succinic anhydride derivative represented by the general formula (2) , React. As a result, a hydroxyl group present at the terminal of the acrylic polymer block reacts with a succinic anhydride derivative to form an ester bond, and a polymer dispersant that is an acrylic polymer having a carboxy group at the terminal is obtained. be able to.

  In addition, (i) after reacting the aforementioned chain transfer agent and the like with a succinic anhydride derivative and the like to obtain a chain transfer agent having a carboxy group; (ii) the obtained chain transfer agent having a carboxy group, etc. Can also be used to radically polymerize the monomer component containing the (meth) acrylic acid ester represented by the general formula (3) using the above-mentioned procedure, to obtain the desired acrylic polymer having a carboxy group at its terminal. it can. However, in the case of the above procedure, a chain transfer agent having a carboxy group or the like may be difficult to dissolve in a low polarity polymerization solvent. For this reason, as described above, it is preferable to produce a polymer dispersant, which is an acrylic polymer having a carboxy group at the end, by the procedure of step (1) → step (2).

  In addition, since succinic anhydride derivatives having a long chain alkyl group and the like are easily dissolved in a low-polar polymerization solvent, they react well with the hydroxyl group present at the end of the acrylic polymer block, and the carboxy group is efficient at the end. Thus introduced polymer dispersing agent can be obtained.

  Of the succinic acid derivative and succinic anhydride derivative, it is preferable to use a succinic anhydride derivative. Although a succinic acid derivative may be used, the yield may be lowered due to the reaction with the end of the acrylic polymer block. Although a halide of a succinic acid derivative can be used, it is necessary to purify after removing the halogen after the reaction.

  For example, the reaction temperature between the acrylic polymer block and the succinic anhydride derivative is preferably 50 to 150 ° C, and more preferably 70 to 130 ° C. A catalyst can also be used in the reaction. As the catalyst, a strong acid such as p-toluenesulfonic acid; a strong base such as 1,8-diazabicyclo [5.4.0] undec-7-ene can be used. When an acrylic polymer block having a plurality of hydroxyl groups at the terminal is used, a graft polymer may be formed by a condensation reaction with a succinic anhydride derivative or the like. However, even when such a graft polymer is formed, it is sufficient that a carboxy group is introduced at the terminal.

<Filler dispersion>
The filler dispersion of the present invention contains a low polarity liquid medium, a filler, and a dispersant for dispersing the filler in the liquid medium. And a dispersing agent is the above-mentioned polymeric dispersing agent. As the liquid medium, the aforementioned low polarity liquid medium is used. Among them, hydrocarbons having 8 or more carbon atoms, alkanols having 8 or more carbon atoms, alkenols having 8 or more carbon atoms, fatty acids having 8 or more carbon atoms, unsaturated fatty acids having 8 or more carbon atoms, fatty acids having 8 or more carbon atoms and hydroxyl groups. It is preferable to use at least one selected from the group consisting of an ester with a compound, an ester of an unsaturated fatty acid having 8 or more carbon atoms and a hydroxyl group-containing compound, and silicone oil. In addition to the low-polarity liquid medium, for example, various organic solvents, monomers, liquid oligomers, and the like can be used.

  As the filler, the aforementioned filler is used. Among these, it is preferable to use at least one selected from the group consisting of titanium dioxide, zinc oxide, iron oxide, and silica. The filler dispersion preferably contains 3 to 50 parts by mass, more preferably 5 to 30 parts by mass of the polymer dispersant with respect to 100 parts by mass of the filler. When the content of the polymer dispersant with respect to 100 parts by mass of the filler is less than 3 parts by mass, it may be difficult to stably disperse the filler. On the other hand, when the content of the polymer dispersant with respect to 100 parts by mass of the filler is more than 50 parts by mass, an excessive polymer dispersant that does not contribute to the dispersion of the filler is included, and the viscosity of the filler dispersion becomes high. It may be easy to gel as well as easily.

  The filler dispersion of the present invention can be obtained by dispersing the filler in the liquid medium according to a conventional method using the above-mentioned low-polarity liquid medium, filler, and polymer dispersant. The filler dispersion may further contain conventionally known additives and resins. Examples of the additive include an ultraviolet absorber, a leveling agent, an antifoaming agent, a pigment derivative (synergist), a dye, and a photopolymerization initiator. As the resin, a photosensitive resin varnish, a non-photosensitive resin varnish, or the like can be used.

  Examples of the photosensitive resin varnish include a photosensitive cyclized rubber resin, a photosensitive phenol resin, a photosensitive polyacrylate resin, a photosensitive polyamide resin, and a photosensitive polyimide resin. Non-photosensitive resin varnishes include cellulose acetate resin, nitrocellulose resin, styrene (co) polymer, polyvinyl butyral resin, aminoalkyd resin, polyester resin, amino resin modified polyester resin, polyurethane resin Resin, acrylic polyol urethane resin, soluble polyamide resin, soluble polyimide resin, soluble polyamideimide resin, soluble polyesterimide resin, hydroxyethyl cellulose, water-soluble salt of styrene-maleic acid ester copolymer, (meth) Examples thereof include water-soluble salts of acrylate (co) polymers, water-soluble aminoalkyd resins, water-soluble aminopolyester resins, and water-soluble polyamide resins. These resin varnishes can be used singly or in combination of two or more.

  After mixing the polymer dispersant, the filler, and the liquid medium, adding various additives as necessary, the filler is dispersed using a disperser until the desired particle size is obtained. Can be obtained. As a disperser, a kneader, an attritor, a ball mill, a sand mill using glass or zircon, a horizontal media disperser, a colloid mill, or the like can be used.

  What is necessary is just to set the particle diameter of the filler in a filler dispersion liquid suitably according to the use of a filler dispersion liquid. The particle diameter of the filler in the filler dispersion can be observed and measured using a transmission electron microscope (TEM) or a light scattering particle size distribution meter. If the filler dispersion obtained by using a centrifuge, ultracentrifuge, or filter is processed to remove mixed foreign substances and coarse particles, the reliability of the filler dispersion can be improved. Is preferable. In addition, what is necessary is just to set the viscosity of a filler dispersion liquid arbitrarily according to a use.

  The filler dispersion liquid of the present invention includes, for example, cosmetics, liquid developers, oil-based inkjet inks, ultraviolet curable inkjet inks, weak solvent-type paints, offset inks, lubricants, cleaning agents, insecticides, release agents, adhesives, and the like. Useful as. Especially, it is suitable as cosmetics and inkjet ink etc. in which fine particles of the filler and dispersion stability are highly required.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples. In the examples and comparative examples, “parts” and “%” are based on mass unless otherwise specified.

<Manufacture of polymer dispersant>
(Synthesis Example 1)
In a reaction vessel equipped with a stirrer, a reverse flow condenser, a thermometer, and a nitrogen introduction tube, 100 parts of n-dodecane, 100 parts of lauryl methacrylate (LMA), 4 parts of thioglycerol (TGL), and 2,2′-azobis (Methyl isobutyrate) (trade name “V-601”, manufactured by Wako Pure Chemical Industries, Ltd. (hereinafter referred to as “V-601”)) 0.1 part was added and polymerized at 80 ° C. for 4 hours while bubbling nitrogen. It was. After addition of 0.05 part of V-601, polymerization was further carried out at 80 ° C. for 3 hours to obtain a polymer solution containing an acrylic polymer block having two hydroxyl groups at its ends. The solid content of the polymer solution measured by sampling was 50.2%. The number average molecular weight (Mn) of the acrylic polymer block measured by GPC using a differential refractive index detector (RI) was 3,600, and the molecular weight distribution (PDI) was 1.64.

  15.9 parts n-dodecylsuccinic anhydride (DSA), 0.2 part 1,8-diazabicyclo [5.4.0] undec-7-ene (DBU) as catalyst and 3 as antioxidant , 5-di-tert-butyl-4-hydroxytoluene (BHT) 0.2 part was added. A part of the reaction solution was sampled and reacted at 120 ° C. for 8 hours while confirming the disappearance of the DSA-derived acid anhydride peak and the reduction of the hydroxyl-derived peak using an infrared spectrophotometer (IR). It was. Thereby, the polymer solution containing the acrylic polymer (SAP-1) which has a carboxy group at the terminal was obtained. The polymer solution obtained had a solid content of 54.4%. The acid value of SAP-1 measured by titration with an ethanolic 0.1N potassium hydroxide solution was 27.3 mgKOH / g. Moreover, Mn of SAP-1 was 3,900 and PDI was 1.85.

(Synthesis Example 2)
In a reaction vessel similar to that used in Synthesis Example 1, 100 parts of n-tetradecane, 100 parts of stearyl methacrylate (SMA), 3 parts of TGL, and 0.1 part of V-601 were placed at 80 ° C. while bubbling nitrogen. For 4 hours. After addition of 0.05 part of V-601, polymerization was further carried out at 80 ° C. for 3 hours to obtain a polymer solution containing an acrylic polymer block having two hydroxyl groups at its ends. The solid content of the polymer solution measured by sampling was 50.3%. The acrylic polymer block had a Mn of 5,200 and a PDI of 1.79.

  15.5 parts of n-octadecyl succinic anhydride (ODSA), 0.2 part of DBU, and 0.2 part of BHT were added. A part of the reaction solution was sampled and reacted at 120 ° C. for 8 hours while confirming the disappearance of the ODSA-derived acid anhydride peak and the reduction of the hydroxyl-derived peak using IR. Thereby, the polymer solution containing the acrylic polymer (SAP-2) which has a carboxy group at the terminal was obtained. The solid content of the obtained polymer solution was 54.6%. The acid value of SAP-2 was 20.0 mgKOH / g, Mn was 5,500, and PDI was 1.83.

(Synthesis Example 3)
In a reaction vessel similar to that used in Synthesis Example 1, a mixture of trimethylolpropane trioctanoate and trimethylolpropane tridecanoate (trade name “Unistar H327R”, manufactured by NOF Corporation (hereinafter referred to as “H327R”) And 100 parts of isodecyl methacrylate (IDMA), 5 parts of TGL, and 0.1 part of V-601 were added and polymerized at 80 ° C. for 4 hours with nitrogen bubbling. After addition of 0.05 part of V-601, polymerization was further carried out at 80 ° C. for 3 hours to obtain a polymer solution containing an acrylic polymer block having two hydroxyl groups at its ends. The solid content of the polymer solution measured by sampling was 50.1%. The acrylic polymer block had a Mn of 2,600 and a PDI of 1.66.

  11.5 parts of n-butyl succinic anhydride (BSA), 0.2 part of DBU, and 0.2 part of BHT were added. A part of the reaction solution was sampled and reacted at 120 ° C. for 8 hours while confirming the disappearance of the BSA-derived acid anhydride peak and the reduction of the hydroxyl group-derived peak using IR. Thereby, the polymer solution containing the acrylic polymer (SAP-3) which has a carboxy group at the terminal was obtained. The polymer solution obtained had a solid content of 53.8%. The acid value of SAP-3 was 35.1 mgKOH / g, Mn was 2,800, and PDI was 1.74.

(Synthesis Example 4)
In a reaction container similar to that used in Synthesis Example 1, 100 parts of silicone oil (trade name “KF-96L-2cs”, manufactured by Shin-Etsu Silicone Co., Ltd. (hereinafter referred to as “KF-96”)), cetyl methacrylate (CMA) 100 parts, 2 parts of TGL, and 0.1 part of V-601 were added and polymerized at 80 ° C. for 4 hours while bubbling nitrogen. After addition of 0.05 part of V-601, polymerization was further carried out at 80 ° C. for 3 hours to obtain a polymer solution containing an acrylic polymer block having two hydroxyl groups at its ends. The solid content of the polymer solution measured by sampling was 50.2%. The acrylic polymer block had a Mn of 8,200 and a PDI of 1.88.

  Tetrapropenyl succinic anhydride (TPSA) 7.9 parts, DBU 0.2 part, and BHT 0.2 part were added. A part of the reaction solution was sampled and reacted at 120 ° C. for 8 hours while confirming the disappearance of the TPSA-derived acid anhydride peak and the reduction of the hydroxyl group-derived peak using IR. Thereby, the polymer solution containing the acrylic polymer (SAP-4) which has a carboxy group at the terminal was obtained. The obtained polymer solution had a solid content of 52.0%. The acid value of SAP-4 was 28.6 mgKOH / g, Mn was 8,500, and PDI was 1.65.

(Comparative Synthesis Example 1)
In a reaction vessel similar to that used in Synthesis Example 1, 100 parts of n-tetradecane, 100 parts of LMA, 4 parts of TGL, and 0.1 part of V-601 were placed and polymerized at 80 ° C. for 4 hours while bubbling nitrogen. . After addition of 0.05 part of V-601, polymerization was further carried out at 80 ° C. for 3 hours to obtain a polymer solution containing an acrylic polymer block having two hydroxyl groups at its ends. The solid content of the polymer solution measured by sampling was 50.9%. The acrylic polymer block had a Mn of 3,700 and a PDI of 1.69.

  Trimellitic anhydride (TMA) 11.4 parts, DBU 0.2 parts, and BHT 0.2 parts were added. Although it heated at 120 degreeC, since TMA was hard to melt | dissolve in n-tetradecane, reaction could not be advanced and the target polymer was not able to be obtained.

(Comparative Synthesis Example 2)
In a reaction vessel similar to the reaction vessel used in Synthesis Example 1, 100 parts of n-dodecane, 100 parts of n-butyl methacrylate (BMA), 4 parts of TGL, and 0.1 part of V-601 were placed while bubbling nitrogen. Polymerization was carried out at 80 ° C. for 4 hours. After addition of 0.05 part of V-601, polymerization was further carried out at 80 ° C. for 3 hours to obtain a polymer solution containing an acrylic polymer block having two hydroxyl groups at its ends. The solid content of the polymer solution measured by sampling was 50.5%. The acrylic polymer block had a Mn of 3,200 and a PDI of 1.70.

  15.9 parts DSA, 0.2 parts DBU, and 0.2 parts BHT were added. A part of the reaction solution was sampled and reacted at 120 ° C. for 8 hours while confirming the disappearance of the DSA-derived acid anhydride peak and the reduction of the hydroxyl-derived peak using IR. As a result, a polymer solution containing an acrylic polymer (CP-1) having a carboxy group at its end was obtained. The resulting polymer solution had a solid content of 52.9%. The acid value of CP-1 was 29.1 mgKOH / g, Mn was 3,600, and PDI was 1.72.

(Comparative Synthesis Example 3)
In a reaction vessel similar to that used in Synthesis Example 1, 100 parts of n-dodecane, 100 parts of LMA, 12 parts of TGL, and 0.1 part of V-601 were placed and polymerized at 80 ° C. for 4 hours while bubbling nitrogen. . After addition of 0.05 part of V-601, polymerization was further carried out at 80 ° C. for 3 hours to obtain a polymer solution containing an acrylic polymer block having two hydroxyl groups at its ends. The solid content of the polymer solution measured by sampling was 52.5%. The acrylic polymer block had a Mn of 2,200 and a PDI of 1.64.

  47.3 parts of TPSA, 0.3 part of DBU, and 0.2 part of BHT were added. A part of the reaction solution was sampled and reacted at 120 ° C. for 8 hours while confirming the disappearance of the TPSA-derived acid anhydride peak and the reduction of the hydroxyl group-derived peak using IR. Thereby, the polymer solution containing the acrylic polymer (CP-2) which has a carboxy group at the terminal was obtained. The polymer solution obtained had a solid content of 61.3%. The acid value of CP-2 was 62.5 mgKOH / g, Mn was 2,800, and PDI was 1.95.

  Table 1 shows the physical properties of the polymers obtained in Synthesis Examples 1 to 4. Table 2 shows the physical properties of the polymers obtained in Comparative Synthesis Examples 1 to 3.

<Preparation of filler dispersion>
Example 1
13.8 parts of polymer solution containing SAP-1 (7.5 parts of polymer, 5% based on filler) and 136.2 parts of decane were uniformly mixed. After adding 150 parts of alumina-treated titanium oxide (number average particle diameter: 210 nm), the mixture was stirred for 30 minutes using a disper to prepare a mill base. Dispersion treatment of mill base prepared at a peripheral speed of 10 m / s using a horizontal media disperser (trade name “Dynomill 0.6 liter ECM type”, manufactured by Shinmaru Enterprises Co., Ltd., zirconia beads (diameter: 0.65 mm)) And the filler was sufficiently dispersed. Filtration was sequentially performed using a 10 μm and 5 μm membrane filter to obtain a white titanium oxide dispersion T-1. The membrane filter was not clogged during filtration. The number average particle size of titanium oxide in the titanium oxide dispersion T-1 measured using a particle size measuring device (trade name “NICOMP 380ZLS-S”, manufactured by International Business Co., Ltd.) was 211 nm. Moreover, the viscosity of the titanium oxide dispersion T-1 measured using an E-type viscometer under the conditions of 25 ° C. and 60 rpm was 9.6 mPa · s.

(Examples 2-5, Comparative Examples 1-3)
Each dispersion was obtained in the same manner as in Example 1 except that the formulation shown in Table 3 was used. In Table 3, “KJCMPA-100” means 3-methoxy-N, N-dimethylpropanamide, which is a polar liquid medium. The numerical value (nm) in parentheses attached to the filler means the number average particle diameter of the filler.

<Evaluation of filler dispersion>
The prepared filler dispersion was put in a light-shielded glass bottle and stored in a thermostatic bath set at 60 ° C. for 1 month. While measuring the viscosity of the filler dispersion after storage and the number average particle size of the filler, the presence or absence of the precipitate after storage and the state of the precipitate by stirring were confirmed. Further, the content after storage was stirred with a spatula to confirm the state of the precipitate, and the number average particle size of the filler after stirring was measured. Furthermore, it evaluated comprehensively according to the evaluation criteria shown below. The results are shown in Table 4.
[Evaluation criteria]
◎ (Very good): No sediment after storage, no substantial change in viscosity and filler particle size ○ (Good): No substantial change in viscosity after storage and particle size of filler × (Poor) : Substantial change in either viscosity after storage or particle size of filler

  In the filler dispersion of Example 1, no supernatant was produced even after storage. When the bottom of the bottle after storage was scooped with a spatula, a slightly viscous sediment was observed. Furthermore, when the contents were stirred with a spatula, most of the sediments disappeared and the original dispersion was restored.

<Application to oil-based inkjet ink>
(Application 1)
The titanium oxide dispersion T-1 obtained in Example 1 was converted into an ink using a color for an oil-based inkjet ink to prepare an oil-based inkjet ink. The ink cartridge filled with the prepared ink was mounted on an ink jet printer, and solid-printed on a surface-treated PET film having a thickness of 50 μm. The obtained printed matter had high optical density and gloss value. Moreover, there was no printing twist and the scratch resistance was good. Furthermore, when a light resistance test was performed using a super UV tester, it was found that the film had sufficient light resistance.

<Application to cosmetics>
(Application example 2)
A cosmetic was prepared using the titanium oxide dispersion T-2 obtained in Example 5. The prepared cosmetic was sufficiently dispersed with titanium oxide and had an excellent UV protection effect. Moreover, it confirmed that the touch feeling (smooth feeling) after apply | coating to skin was excellent.

  The polymer dispersant of the present invention is suitable as a dispersant for stably dispersing a filler in a low polarity liquid medium.

Claims (8)

A polymer dispersant used to disperse a filler in a low polarity liquid medium,
Reaction of an acrylic polymer block having one or more hydroxyl groups at its terminal with at least one of a succinic acid derivative represented by the following general formula (1) and a succinic anhydride derivative represented by the following general formula (2) An acrylic polymer having a carboxy group at its end,
Content of the structural unit derived from the (meth) acrylic acid ester represented by following General formula (3) is 80 mass% or more,
A polymer dispersant having a polystyrene-equivalent number average molecular weight of 2,000 to 12,000 as measured by gel permeation chromatography.

(In the general formula (1) and (2), R ₁ is in indicates the number 4 or more alkyl or alkenyl group having a carbon. The general formula (3), R ₂ represents a hydrogen atom or a methyl group, R ₃ Represents an alkyl group having 8 to 22 carbon atoms) It is a manufacturing method of the polymer dispersing agent according to claim 1,
In a polymerization solvent, using at least one of an azo radical initiator having one or more hydroxyl groups and a chain transfer agent, a monomer component containing a (meth) acrylic acid ester represented by the following general formula (3) is polymerized. Obtaining an acrylic polymer block having one or more hydroxyl groups at its ends;
Reacting the acrylic polymer block with at least one of a succinic acid derivative represented by the following general formula (1) and a succinic anhydride derivative represented by the following general formula (2);
The manufacturing method of the polymeric dispersing agent which has.

(In the general formula (1) and (2), R ₁ is in indicates the number 4 or more alkyl or alkenyl group having a carbon. The general formula (3), R ₂ represents a hydrogen atom or a methyl group, R ₃ Represents an alkyl group having 8 to 22 carbon atoms)   The method for producing a polymer dispersant according to claim 2, wherein the content of the structural unit derived from the (meth) acrylic acid ester in the acrylic polymer block is 90% by mass or more.   The polymerization solvent is selected from the group consisting of hydrocarbons having 8 or more carbon atoms, alkanols having 8 or more carbon atoms, fatty acids having 8 or more carbon atoms, esters of fatty acids having 8 or more carbon atoms and a hydroxyl group-containing compound, and silicone oil. The method for producing a polymer dispersant according to claim 2 or 3, wherein the polymer dispersant is at least one kind. A filler dispersion containing a low polarity liquid medium, a filler, and a dispersant for dispersing the filler in the liquid medium,
A filler dispersion, wherein the dispersant is the polymer dispersant according to claim 1.   The filler dispersion according to claim 5, wherein the filler is at least one selected from the group consisting of titanium dioxide, zinc oxide, iron oxide, and silica.   The liquid medium is a hydrocarbon having 8 or more carbon atoms, an alkanol having 8 or more carbon atoms, an alkenol having 8 or more carbon atoms, a fatty acid having 8 or more carbon atoms, an unsaturated fatty acid having 8 or more carbon atoms, or a fatty acid having 8 or more carbon atoms. The filler dispersion according to claim 5 or 6, which is at least one selected from the group consisting of an ester with a hydroxyl group-containing compound, an ester of an unsaturated fatty acid having 8 or more carbon atoms and a hydroxyl group-containing compound, and silicone oil.   The filler dispersion according to any one of claims 5 to 7, comprising 3 to 50 parts by mass of the polymer dispersant with respect to 100 parts by mass of the filler.