JPH09296134A - Water-repellent and oil-repellent powder and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject powder useful as e.g. a coating material, by treating the surface of powder with a fluorine-contg. group-modified (meth) acrylic ester copolymer to enable the formation of uniform film firmly adhered to the powder. SOLUTION: This powder is obtained by uniformly coating the surface of inorganic and/or organic powder with a solvent solution of a fluorocopolymer containing, as the essential constituent, a fluoro(meth)acrylic ester of the formula CH2 =CR<1> COORf (R<1> is H or methyl; Rf is a substituted polyfluoroalkyl or polyfluoroether) or an emulsifier-contg. aqueous emulsion of the above copolymer followed by evaporating the water or the organic solvent. It is preferably that at least one kind of saline selected from vinylsilances of the formula (R<2> is a 1-8C alkyl; R<3> is a 1-4C alkyl or alkoxy-substituted group; (m) is 0 or 1; (c) is 1-3) and (meth)acryloyloxy-contg. silanes is the other essential constituent(s) of the copolymer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to powders such as pigments used in paints and cosmetics, and more particularly to powders having water and oil repellency and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, powders such as pigments applied to paints and cosmetics can be roughly classified into inorganic powders and organic powders. Of these, inorganic powders are usually complex oxides, which have hydroxyl groups on the surface, and the amount of the hydroxyl groups differs depending on the type of powder. For this reason, there are differences in the degree of hydrophilicity and lipophilicity of the surface depending on the type of powder, and there are various powders with different surface activities.

Further, due to a difference in particle size and shape due to mechanical impact force of the fine surface, or a difference in surface activity due to expression (production) of a new surface, a difference in wettability with water or an organic substance. , In paint,
This caused unevenness and floating of the coating film, and in cosmetics, it was the cause of collapse of the cosmetic film and lack of adhesion.

As means for solving these drawbacks, various methods have been proposed as follows. I. Method of surface treatment of powder with metallic soap and surfactant b. Method of baking treatment on the powder surface with polysiloxane or the like having ≡SiH group (for example, Japanese Patent Publication No. 41-9890) c. However, all of the above methods have drawbacks such as insufficient adhesion and insufficient water / oil repellency.

In order to overcome these drawbacks, an inorganic powder base is reacted with a gaseous water-repellent and oil-repellent agent by heating, and the water- and oil-repellent agent is reactively bonded to an active site on the surface of the base. To form a vapor-deposition coating layer on the surface of the base (Japanese Patent Application Laid-Open No. HEI-1)
-318070 publication) was proposed. However,
This method cannot handle heat-sensitive materials such as yellow iron oxide and dark blue. There is also a method of using a catalyst to lower the baking temperature (see, for example, Japanese Patent Publication No.
No. 18899), the catalyst remaining after baking accelerates the decomposition of the surface-treated substance and other coexisting components, and therefore cannot be used in paints and cosmetics.

[0006]

The inventors of the present invention have made extensive studies in order to solve the above-mentioned drawbacks. As a result, the fluorine-containing group-modified (meth) acrylic monomer copolymer was formed on the surface of the powder at a low temperature. It was found that the treatment makes it possible to form a uniform treated film not only on the surface of the inorganic powder but also on the surface of the organic powder, and imparts water repellency and oil repellency to the present invention.

Therefore, a first object of the present invention is to provide a powder having water and oil repellency, which is suitable for pigments such as paints and cosmetics. A second object of the present invention is to provide a method for producing a powder having water / oil repellency, which is suitable for pigments such as paints and cosmetics.

[0008]

The above-mentioned various objects of the present invention are achieved by treating the surface of an inorganic or organic powder with a fluorine-containing copolymer having a fluorine-containing (meth) acrylic ester as an essential component. And a powder having water and oil repellency and a method for producing the same.

Examples of the inorganic powder which can be used in the present invention include titanium oxide, zinc oxide, iron oxide, iron oxide yellow, chromium oxide, ultramarine blue, dark blue, talc, mica, sericite, diatomaceous earth, Examples thereof include aluminum powder, calcium carbonate, hydroxyapatite, silica and carbon powder. As the organic powder, for example, resin powder such as polystyrene and polyethylene,
Examples thereof include organic pigments such as Red No. 201 and Yellow No. 202, natural pigments such as chlorophyll and β-carotene, rubber powders such as urethane, neoprene and silicone, silicone gel, silicone products such as silsesquioxane.

In the present invention, the fluorine-containing copolymer to be used contains at least a fluorine-containing acrylic acid ester or a fluorine-containing methacrylic acid ester represented by the following general formula (1) as an essential component. It is also preferable to contain a (meth) acryloxy group-containing silane represented by the general formula (2). Formula _{(1): CH 2 = CR} 1 COOR f where, R ¹ in the formula is a hydrogen atom or a methyl group, R _f is a hydrogen atom alkylene ethers having 6 to 22 alkyl carbon atoms or 1 to 20 carbon atoms It is a polyfluoroalkyl group or a polyfluoroether group in which some or all are substituted with fluorine atoms.

Specific examples of Rf in the above general formula (1) include groups represented by the following chemical formula 1.

Embedded image From the viewpoint of effectively imparting the water and oil repellency effect, the amount of the compound represented by the general formula (1) used is preferably 50 to 99.9% by weight in the copolymer.

In the present invention, in order to improve the adhesion of the fluorine-containing copolymer to the powder surface, the following general formula is used together with the fluorine-containing (meth) acrylic acid ester represented by the above general formula (1). Vinylsilane represented by (2),
Also, it is preferable to perform a coating treatment on the surface of the powder by using the fluorine-containing copolymer produced by adding at least one silane selected from the (meth) acryloxy group-containing silanes as an essential component. .

General formula (2): CH ₂ = CR ¹ (COOCH ₂ CH ₂ CH ₂ ) _m -SiR ² _3-c (OR ³ ) _c where R ¹ is a hydrogen atom or a methyl group and R ² is a carbon number. 1 to
8 is an alkyl group, R ³ is an alkyl group having 1 to 4 carbon atoms, an alkoxy-substituted alkyl group, or an alkenyl group, m is 0 or 1, and C is 1, 2 or 3.

Specific examples of the silane represented by the general formula (2) include compounds represented by the following chemical formula 2.

Embedded image From the viewpoint of improving the adhesiveness of the copolymer, the amount of the compound represented by the general formula (2) used is 0.
It is preferably from 1 to 10.0% by weight.

The strength of the powder coating provided in the present invention,
In the present invention, a vinyl-based monomer copolymerizable with the compounds represented by the general formulas (1) and (2) in order to adjust hardness, adhesion to a substrate, stain resistance and the like. Can be used as appropriate. Specific examples of the vinyl-based monomer include acrylates or methacrylates such as methyl (meth) acrylate, ethyl (meth) acrylate and n-butyl (meth) acrylate, aromatic vinyl compounds such as styrene and vinyltoluene. Dicarboxylic acids such as carboxylic acid, maleic acid, and fumaric acid, and 1 to 1 carbon atoms
And diethers with monohydric alcohols, vinyl ethers such as n-butyl vinyl ether and cyclohexyl vinyl ether.

As a coating treatment method using a fluorine-containing copolymer in the present invention, first, a solvent solution of the copolymer is prepared, or an aqueous emulsion is prepared by emulsion copolymerization in the presence of an emulsifier. By making them, applying them to the powder by spraying or the like, or by dispersing the powder in these liquids and attaching the copolymer to the surface of the powder, by evaporating water or an organic solvent, The method of forming a film can be mentioned.

The organic solvent for preparing the copolymer solution is
The copolymer is not particularly limited as long as it can be easily dissolved and easily evaporated, and specific examples thereof include ketones such as methyl ethyl ketone and methyl isobutyl ketone, and m-xylene hexafluoride and tri Fluorine-containing hydrocarbons such as fluoromethylbenzene may be mentioned.

The temperature at which the water or organic solvent is evaporated after the copolymer is attached to the powder varies depending on the type of solvent, but the range is preferably 20 ° C to 150 ° C. It is also possible to evaporate the water or organic solvent under reduced pressure. The powder of the present invention thus obtained can be used as a pigment for paints and cosmetics.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION The powder of the present invention comprises a solvent solution or an aqueous emulsion of a fluorine-containing copolymer containing the fluorine-containing (meth) acrylic acid ester represented by the general formula (1) as an essential component. It can be obtained by dispersing powder prepared and appropriately selected in the solvent solution or the aqueous emulsion, adhering the copolymer on the powder surface, and then evaporating water or an organic solvent.

[0020]

INDUSTRIAL APPLICABILITY The powder having water repellency and oil repellency according to the present invention has a uniform coating formed thereon and the coating adheres to the surface of the powder. Further, the coating treatment may be carried out by an extremely simple method such as coating or adhering on the surface of the powder. Moreover, in that process, since it can be carried out at a low temperature without using a catalyst, it is possible to process even a powder which is weak against heat, and there is no influence due to the catalyst remaining.

[0021]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.
Unless otherwise specified, “parts” and “%” described below mean “parts by weight” and “% by weight”, respectively.

Synthetic Example 1. A 200 ml flask was charged with 1.1 parts of maleic acid and 23.8 parts of methyl isobutyl ketone (MIBK), and the mixture was placed under a nitrogen stream at 60.
Heat to ℃, azobisisobutyronitrile (AIB
N) After adding 0.06 part, 13.5 parts and 7.9 parts of the compounds represented by the following chemical formulas 3 and 4, respectively, and further, AIBN 0.06 part and MIBK 3.8 parts are added. The reaction was carried out at 60 to 65 ° C for 16 hours.

[0023]

Embedded image

Embedded image After completion of the reaction, the mixture was cooled to room temperature and 100 parts of MIBK was added to dilute the reaction solution to obtain a fluorinated methacrylic acid ester copolymer solution. The nonvolatile content of the obtained solution was 14.8%.

Synthesis Example 2. In a 200 ml flask equipped with a stirrer, 28.0 parts of a compound represented by the following chemical formula 5 and polyoxyethylene lauryl ether
8 parts, 0.8 parts of trimethyloctadecyl ammonium chloride, 0.28 parts of lauryl mercaptan, 14.0 parts of acetone, and 56.4 parts of deoxygenated pure water,
After thoroughly stirring under a nitrogen stream for about 1 hour at 60 ° C, 2,2-azobis (2-amidinopropane)
0.28 parts of dihydrochloride was added, and the mixture was further stirred at 60 ° C. for 5 hours to prepare an emulsion having a nonvolatile content of 30.0%.

Embedded image

Synthesis Example 3. Compound 2 represented by the above chemical formula 5
Instead of 8.0 parts, compound 19.
Using 6 parts, lauryl mercaptan 0.28
In the same manner as in Synthesis Example 2 except that 8.1 parts of stearyl acrylate was used in place of parts, the nonvolatile content was 29.1.
% Emulsion was made.

[Chemical 6]

Synthesis Example 4. In a 1 liter flask equipped with a stirrer, the compound represented by the above chemical formula 5 was added to a 60.
0 part, 1.0 part of the compound represented by the following chemical formula 7, 35 parts of lauryl methacrylate, 5 parts of 2-hydroxyethyl methacrylate, 290 parts of deoxygenated pure water, and 100 parts of acetone.
Parts, 2.5 parts of trimethyloctadecyl ammonium chloride, and 2.5 parts of polyoxyethylene lauryl ether were added, and thoroughly stirred under a nitrogen stream for about 1 hour while maintaining at 60 ° C., then deoxidized pure water 4 parts. A solution in which 0.4 part of azobisisobutylamidine hydrochloride was dissolved was added to the above, and the mixture was further heated and stirred at 60 ° C. for 5 hours to give a nonvolatile content of 2
A 1.0% emulsion was made.

[Chemical 7]

Synthesis Example 5. The nonvolatile content was the same as in Synthesis Example 2 except that 28.0 parts of stearyl acrylate was used instead of 28.0 parts of the compound represented by Chemical formula 5 used in Synthesis Example 2 and lauryl mercaptan was not used. A 29.3% emulsion was made.

Examples 1 to 4. After adjusting the solid content concentration of each treatment liquid obtained in Synthesis Examples 1 to 4 to 20%,
0 part was placed in a 300 ml flask equipped with a stirrer, 100 parts of titanium oxide powder was added as powder, and the mixture was stirred at 60 ° C. for 1 hour. 80 ° C / 2mmHg
The solvent was distilled off with and dried under reduced pressure to obtain treated powders 1 to 4.

Embodiment 5 FIG. After adjusting the solid content concentration of the treatment liquid obtained in Synthesis Example 1 to 20%, 50 parts of the solution was put into a 300 mi limitle flask equipped with a stirrer, and 100 parts of dark blue powder was added as powder. , At 25 ℃ 1
Stir for hours. The solvent is distilled off at 25 ° C / 2 mmHg,
It was dried under reduced pressure to obtain a treated powder 5.

The treated powders thus obtained were spread in aluminum petri dishes (diameter: 60 mm, height: 9 mm), and pure water or squalane was added dropwise to the water and oil repellency tests.

Table 1 shows the results of judgment of the test results based on the following criteria. It retains the shape of the droplets and has no penetration. . . . . . . . . . . . . . ◎ The shape of the droplet is retained, but it is slightly soaked. . . . . . . . . ○ The liquid droplets have spread and are soaking in. . . . . . . . . . . . △ There are no liquid droplets remaining, and they are all infiltrated. . . . . . . . . . . . . . ×

[0032]

[Table 1] ──────────────────────── Test test powder Water repellency Oil repellency ─────────────── ────────── Example 1 treated powder 1 ◎ ○ Example 2 treated powder 2 ◎ ○ Example 3 treated powder 3 ◎ ◎ Example 4 treated powder 4 ◎ ◎ ◎ Example 5 treated Powder 5 ○ ○ Comparative example 1 Treated powder 6 △ △ Comparative example 2 Impossible to measure due to decomposition Comparative example 3 Untreated powder × × ───────────────────── ────

Comparative Example 1 Using the treatment liquid obtained in Synthesis Example 5, treated powder 6 was prepared in exactly the same manner as in Examples 1 to 4, and the water repellency and oil repellency of the powder were tested and evaluated in exactly the same manner. The results are as shown in Table 1.

Comparative Example 2. 100 parts of a 10% solution of methyl hydrogen polysiloxane in toluene was placed in a 300 ml flask equipped with a stirrer, 100 parts of navy blue powder as powder and 0.1 part of zinc octoate were added, and heated at 150 ° C. Then, the color gradually changed and a decomposition gas was generated.

Comparative Example 3 Using the titanium oxide powder which is the base of the powder before treatment, water repellency and oil repellency tests were conducted in the same manner as in Examples 1 to 4, and the evaluation results are shown in Table 1.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location C09K 3/18 104 C09K 3/18 104

Claims (3)

[Claims] 1. A fluorine-containing copolymer having, as an essential component, at least the surface of an inorganic or organic powder, the fluorine-containing (meth) acrylic acid ester represented by the general formula (1) CH ₂ ═CR ¹ COOR _f. A water- and oil-repellent powder obtained by treating with R; wherein R ¹ is a hydrogen atom or a methyl group, and R is
_f is an alkyl group having 1 to 20 carbon atoms or 6 carbon atoms
22 is a polyfluoroalkyl group or a polyfluoroether group in which some or all of the hydrogen atoms of the alkyl ether of 22 are substituted with fluorine atoms. 2. The fluorine-containing copolymer further has the formula (2) CH ₂ ═CR ¹ — (COOCH ₂ CH ₂ CH ₂ ) _m.
The fluorine-containing copolymer containing at least one silane selected from vinylsilane represented by —SiR ² _3-C (OR ³ ) _C and silane containing a (meth) acryloxy group as an essential component. R ¹ is a hydrogen atom or a methyl group, R ² is an alkyl group having 1 to 8 carbon atoms, and R ³ is 1 to 1 carbon atoms.
4, an alkyl group, an alkoxy substituent, or an alkenyl group, m is 0 or 1, and C is 1, 2 or 3. 3. A solution of a fluorine-containing copolymer represented by the general formula (1) CH ₂ ═CR ¹ COOR _f on the surface of an inorganic and / or organic powder, or a solution containing the emulsifier. A method for producing a powder having water and oil repellency, which comprises uniformly applying and adhering an aqueous emulsion of a fluorocopolymer and then evaporating water or an organic solvent; provided that R ^{1 in} the formula Is a hydrogen atom or a methyl group, and R _f is a polyfluoroalkyl group or a polyfluoroalkyl group in which part or all of the hydrogen atoms of an alkyl group having 1 to 20 carbon atoms or an alkyl ether having 6 to 22 carbon atoms are substituted with fluorine atoms. It is an ether group.