JPS60163973A - Production of hydrophobic powder - Google Patents

Abstract

PURPOSE:To obtain the titled powder which is highly reactive with silicone, does not cause change in hydrophobicity and has excellent moldability, by reacting a specified organohydrogenpolysiloxane in the presence of an acidic substance on the surfaces of an inorg. powder and/or an org. powder. CONSTITUTION:0.1-10wt% organohydrogenpolysiloxane of the formula (wherein R1, R2 are each H, hydroxyl, methyl, ethyl, phenyl; R3, R4 are each H, hydroxyl, a 1-22C alkyl, phenyl, a 1-22C alkoxy, a 1-4C cyanoalkyl; the sum of l, m and n is 5-1,000) and having an SH equivalent of 30-550, an inorg. powder and/or an org. powder (e.g. talc, PP) and 0.01-10wt% acidic substance (e.g. citric or phosphoric acid) are dispersed or dissolved in a solvent (e.g. dichloromethane) and mixed while heating to effect the reaction of the polysiloxane on the surface of the powder.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing hydrophobic powder. More specifically, the present invention relates to a method for producing hydrophobic powder, which comprises adding an acidic substance when producing hydrophobic powder by reacting organohydrogenpolysiloxane on the surface of the powder.

There have been many known methods for making hydrophilic powders hydrophobic, and in particular, it is already well known to utilize the hydrophobic properties of silicone oil.

The present inventors first homogeneously mixed and ground metal hydroxide, which is a catalyst for initiating crosslinking polymerization of reactive silicone oil, into various hydrophilic powders, and then methyl hydroxide having a predetermined amount of reaction activity. Discovered a method for producing hydrophobic powder by mechanochemically forming hydrogen polysiloxane on the surface of the powder through cross-linking polymerization without any particular heat treatment (Japanese Patent Publication No. 56-43
264).

The powder obtained by the above method was an excellent hydrophobic powder with strong hydrophobicity, which did not discolor and did not contain any single silicone resin lumps. However, in some cases, the reaction of the organohydrogenpolysiloxane on the powder may not be sufficient and the reaction may proceed further over time, resulting in changes in hydrophobicity or poor moldability when made into a solid foundation. I could see it.

As a result of intensive research to improve these drawbacks, the present inventors have discovered that by adding an acidic substance when producing hydrophobic powder by reacting organohydrogenpolysiloxane on the surface of the powder, silicone It has been found that a hydrophobic powder with a high reaction rate and without the drawbacks mentioned above can be obtained, and that this method is not limited to mechanochemical reactions and can be applied to various powder processing steps.

That is, the present invention provides a method for producing hydrophobic powder by reacting one or more organohydrogen polysiloxanes on the surface of one or more powders selected from inorganic powders and organic powders. The present invention provides a method for producing a hydrophobic powder, characterized in that one or more acidic substances are added to the powder.

The powders used in the present invention are: silicic acid/silicic anhydride, magnesium silicate, talc, kaolin, mica monobentonite, bismuth oxychloride, zirconium oxide, magnesium oxide, zinc oxide, titanium dioxide, calcium carbonate,
Magnesium carbonate, monoiron oxide, ultramarine blue, navy blue, chromium oxide,
Inorganic powders such as chromium hydroxide, calamine, carbon black and composites thereof, polyamides, polyesters,
Polyethylene, polypropylene, polystyrene hebomelamine resin, epoxy resin, polycarbonate resin, divinylbenzene-styrene copolymer, copolymer consisting of two or more monomers of the above compounds, celluloid, acetylcellulose, poly[t, protein, Organic powder such as scleroprotein, CI pigment yellow, C epigment orange, O epigment red, C epigment violet, C epigment pull = Sc epigment green, and C epigment brown, and any one of these A species or two or more species are selected and used.

The organohydrogen polysiloxane used in the present invention is selected from one or more compounds represented by the following general formula. Among these, it has an active hydrogen group that directly bonds to silicon and has an SiH equivalent (the number of grams of organohydrogen polysiloxane required to generate 1 mole of hydrogen gas in a 0,0IN NaOH aqueous solution at 100°C) of 550 or less. Those with a molecular weight of 30 to 550 are particularly preferred.

(In the formula, R1 may be the same or different, and represents a hydrogen atom, a hydroxyl group, a methyl group, an ethyl group, or a phenyl group,
R2 is a hydrogen atom, a hydroxyl group, a methyl group, an ethyl group, or a phenyl group. R3 may be the same or different, and is a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 22 carbon atoms, a phenyl group, or a phenyl group having 1 to 22 carbon atoms. Alkoxy group or carbon number 1-4
S4 may be the same or different, and S4 may be the same or different, and may be a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 22 carbon atoms, a phenyl group, an alkoxy group having 1 to 22 carbon atoms, or a cyano group having 1 to 4 carbon atoms. Indicates an alkyl group, l % m
s n represents an integer of 5 to 1000 in total. l s
In m % n, each constituent unit may be bonded regularly or irregularly, or a collection of several of each constituent unit may be bonded regularly or irregularly.

SiH equivalent is an important factor that determines the degree of crosslinking polymerization of organohydrogenpolysiloxane; a small SiH equivalent produces a hard coating, that is, a polymer with a high degree of crosslinking, and a high SiH equivalent produces a viscous coating, that is, a polymer with a high degree of crosslinking. Forms polymers with low If the su4 equivalent is below, an extremely hard film will be formed, and although hydrophobization will proceed, it will likely differ from the usage characteristics of the starting powder, and prevention of silicone-only resin lumps will require the use of polymerization intermediates (oligos). It will be difficult until it is created. Si
When the H equivalent exceeds 550 ~ soft film formation occurs,
Hydrophobicization progresses relatively slowly.

(The following is a blank space) The amount of organohydrogenpolysiloxane added may be 01 to 2 D% (wt/wt) based on the starting powder, and is preferably determined based on the specific surface area of the starting powder. Since the powder surface characteristics differ depending on each powder, it cannot be said that it is uniform, but in general, 101n9 of organohydrogenpolysiloxane per 1 m' is sufficient.

Acidic substances used in the present invention include fatty acids, polybasic acids, lactic acid, malic acid, tartronic acid, citric acid, isocitric acid, tartaric acid, ascorbic acid, vitamin A acid, aromatic acids, urocanic acid, pyrrolidone carboxylic acid, Acidic amino acids, neutral amino acids, acylamino acids, glycono delta-
Examples include lactone, sulfuric acid, hydrochloric acid, phosphoric acid, boric acid, inorganic acid salts of amino acids, organic acid salts of amino acids, inorganic acid salts of acylamino acids, organic acid salts of acylamino acids, metal salts of inorganic acids, etc. One or more types are selected from these.

Conventionally, alkaline substances and organic acid salts of various metals have been used as reaction accelerators for organohydrogenpolysiloxanes. In particular, hydrophobic powders using metal hydroxides as reaction accelerators do not discolor and have excellent hydrophobicity, as described above, and are close to ideal as powders for cosmetics (Japanese Patent Publication No. 56-43264). .

However, there remained room for improvement in terms of the reaction rate of the organohydrogen polysiloxane used. This only problem is also solved by the addition of acidic substances according to the present invention, but the amount of these acidic substances added is 0.0% relative to the starting powder.
It may be 0.01 to 10% (wt/wt), and preferably 0.01 to 5% (wt/wt) from the viewpoint of hydrophobicity.

Various processes can be employed to produce hydrophobic powders according to the present invention. To add organohydrogenpolysiloxane to raw material powder - It may be added after being diluted with a solvent, or it may be added directly.

Also, it may be sprayed in a gaseous state. These operations may be performed while mixing and stirring, or mixing and stirring may be performed after addition. The mixing and stirring method may be a commonly used method, and no special equipment is required. A mechanochemical method, specifically a ball mill, a hodgersite ball mill, a vibrating ball mill, a vibrating rondo mill, a vibrating mill, an attriter, a bot mill, a rondo mill, a pan mill, a crusher, etc., can also be used for mixing and stirring. The mechanochemical method is a particularly excellent method for uniformly mixing powders, acidic substances, and organohydrogenpolysiloxanes.

The order of addition of the raw material powder, acidic substance, and organohydrogenpolysiloxane is not particularly limited.

The organohydrogenpolysiloxane may be added after mixing the raw material powder and the acidic substance, or a mixture of the acidic substance and the organohydrogenpolysiloxane may be added to the raw material powder, or the raw material powder and the organohydrogenpolysiloxane may be mixed together. Acidic substances may be added to the siloxane mixture.

If the above production method is carried out under heating, the reaction will proceed more quickly.

Hydrophobic powder coated with silicone resin by the production method of the present invention can be used as powder for cosmetics, inorganic additives for plastics (reinforcing agents, colorants, etc.), inorganic additives for rubber (mainly adhesives), magnetic tapes, etc. It is widely used in applications such as magnetism (iron oxide), paints, inorganic pigments for ink, and lubricants.

The present invention will be explained in more detail below by way of examples.

A mixture of 200 parts by weight of tungsten was heated to reflux at 50° C. with stirring, and then heated and stirred at 100° C. for 2 hours to distill off the tungsten in a dichloromethane chamber. The reaction rate of the methylhydrogen polysiloxane at this time was 62%.

Comparative Example 1 When treated in exactly the same manner as in Example 1 without adding citric acid, the reaction rate of methylhydrogen polysiloxane was 10%.

Example 2 A mixed powder of 46.8 parts by weight of titanium dioxide and 46.8 parts by weight of talc was mixed and polished for minutes in a vibrating ball mill (Chuo Kakokiko type, 1.5 H) with 0.2 parts by weight of phosphoric acid. After crushing
3 parts by weight of methylhydrogenpolysiloxane having an SIH equivalent of 145 was added, and the mixture was mixed and ground in the vibrating ball mill for 0 minutes. The reaction rate of methylhydrogen polysiloxane at this time was 58%.
Met.

Comparative Example 2 The reaction rate of methylhydrogen polysiloxane was 9% when treated in exactly the same manner as in Example 2 except that calcium hydroxide was used instead of phosphoric acid.

Example 3 Titanium dioxide, kaolin, magnesium oxide, silicic acid,
85 parts by weight of a powder mixture of equal amounts of titanium-coated mica, 5 parts by weight of glutamic acid, and 210 parts by weight of methylhydrogen polysiloxane of SiH Tokei 550 were mixed and ground in a bot mill for 5 hours. The reaction rate of methylhydrogen polysiloxane at this time is 6
Comparative Example 3 The reaction rate of methylhydrogen polysiloxane when treated in the same manner as in Example 3 without adding glutamic acid was 12%. 89.5 parts by weight of iron oxide, 5 parts by weight of nylon powder, 0.5 parts by weight of zinc sulfate, and 5 parts by weight of methylhydrogen polysiloxane having an SiH equivalent of 252 were mixed and ground in a bot mill for 5 hours. The reaction rate of the methylhydrogen polysiloxane at this time was 49%.

Comparative Example 4 Using aluminum hydroxide instead of zinc sulfate, Example 4
When treated in exactly the same manner as above, the reaction rate of methylhydrogen polysiloxane was 16%.

Example 5 Parts by weight of red iron oxide, 48.9 parts by weight of talc, 01 parts by weight of lactic acid
parts by weight and 1 part by weight of ethylhydrogen polysiloxane having an SiH equivalent of 35 were mixed and milled in a bot mill for 5 hours. The reaction rate of the ethyl hydrogen polysiloxane at this time was 42%.

Comparative Example 5 When treated in exactly the same manner as in Example 5 using magnesium hydroxide instead of lactic acid, the reaction rate of ethylhydrogen polysiloxane was 18%.

Example 6 Yellow iron oxide 925 parts by weight, kaolin 5 parts by weight, tartaric acid 0
5 parts by weight of methylethylhydrogen polysiloxane having an SiH equivalent of 79 and 2 parts by weight were mixed and ground in a bot mill for 5 hours. The reaction rate of the methyl ethyl hydrogen polysiloxane at this time was 51%.

Comparative Example 6 When treated in exactly the same manner as in Example 6 using aluminum hydroxide instead of tartaric acid, the reaction rate of methylethylhydrogen polysiloxane was 9%.

Example 7 Yellow iron oxide 513 parts by weight, kaolin 5 parts by weight, adipic acid 0.2 parts by weight, malic acid 05 parts by weight, SiH equivalent 14
2 parts by weight of methylhydrogen polysiloxane No. 5 and Sl, H
One part by weight of methylphenylhydrogen polysiloxane having an equivalent weight of 127 was mixed and milled in a bot mill for 5 hours. The reaction rate of the methylphenyl hydrogen polysiloxane at this time was 57%.

Comparative Example 7 When treated in exactly the same manner as in Example 7 without adding adipic acid and malic acid, the reaction rate of methylphenylhydrogen polysiloxane was 6%.

In Examples 1 to 7 and Comparative Examples 1 to 7, the reaction rate of organohydrogenpolysiloxane was calculated by the following method.

Patent applicant: Shiseido Co., Ltd. Voluntary writing of procedural amendments) March 5, 1982 Mr. Kazuo Wakasugi, Commissioner of the Patent Office, F.

-, g''・ 1. Indication of the case Patent Application No. 20433 of 1982 2. Name of the invention Method for producing hydrophobic powder 3. Person making the amendment 4. Detailed description of the invention in the specification to be amended Column 5, Contents of amendment (1) On page 13 of the specification, in the first line from the bottom, the word "adhesive" will be corrected to "colorant."

(2) 3rd line from the bottom of page 14 of the specification “Chuo Kakoki Type I”
The statement has been corrected to read "Chuo Kakoki Type 1".

(3) “Methylphenyl” on page 17 of the specification, line 4 from the bottom
Correct the wording to "organo".

(4) "Methylphenyl" in the first line of page 18 of the specification will be corrected to "organo."

that's all

Claims (10)

[Claims] (1) Organohydrogenpolysiloxane 1 on the surface of one or more powders selected from inorganic powders and organic powders.
A method for producing a hydrophobic powder, which comprises adding one or more acidic substances when producing the hydrophobic powder by reacting one or more species. (2) The inorganic powder is silicic acid, silicic anhydride, magnesium silicate, talc, kaolin, mica, bentonite, titanium-coated mica, bismuth oxychloride, zirconium oxide,
Claim (1) which is any one of magnesium oxide, zinc oxide, titanium dioxide, calcium carbonate, magnesium carbonate, iron oxide, ultramarine, deep blue, chromium oxide, chromium hydroxide, calamine, and carbon brazier. A method for producing hydrophobic powder. (3) If the organic powder is polyamide, polyester, polyethylene, polypropylene, polystyrene, polyurethane, vinyl resin, urea resin, phenol resin, fluororesin, silicone resin, acrylic resin, melamine resin, epoxy resin, polycarbonate resin, divinylbenzene, Styrene copolymer, copolymer consisting of two or more monomers of the above compounds, celluloid, acetyl cellulose, polysaccharide, protein, hard protein, CI Pidamento Yellow, CI Pigment Orange, CI Pigmentore, Do, C
Evigument Violet, CI Pigement Blue, C
A method for producing a hydrophobic powder according to claim 1, which is either I pigment green or O pigment brown. (4) Claim No. 1 in which the organohydrogen polysiloxane is any of the compounds represented by the following general formula.
) to (3). (In the formula, R1 may be the same or different, and represents a hydrogen atom, a hydroxyl group, a methyl group, an ethyl group, or a phenyl group,
R2 represents a hydrogen atom, a hydroxyl group, a methyl group, an ethyl group, or a phenyl group, and R3 may be the same or different, and represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 22 carbon atoms, a phenyl group, or Alkoxy group or carbon number 1-4
R4 may be the same or different from each other, and R4 may be the same or different, and is a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 22 carbon atoms, a phenyl group, an alkoxy group having 1 to 22 carbon atoms, or a cyanoalkyl group having 1 to 4 carbon atoms. 7. m and n represent integers of 5 to 1000 in total. In l and mXn, the respective constituent units may be bonded regularly or irregularly, or a collection of several respective constituent units may be bonded regularly or irregularly. ) (5) SiH of organohydrogen polysiloxane ff1
(The number of grams of organohydrogenpolysiloxane required to generate 1 mole of hydrogen gas at 100°C in a 0,01N NaOH aqueous solution) is w~550 (
4) The method for producing the hydrophobic powder described in section 4). (6) Claim No. 1, wherein the amount of organohydrogenpolysiloxane added is 0.1 to % by weight based on the powder.
A method for producing a hydrophobic powder according to any one of items 1 to 5. (7) Acidic substances include fatty acids, polybasic acids, lactic acid, malic acid,
Tartronic acid, citric acid, isocitric acid, tartaric acid, ascorbic acid, vitamin A acid, aromatic acid, urocanic acid,
pyrrolidone carboxylic acid, acidic amino acids, neutral amino acids,
Acylamino acid, Glufu-δ-lactone, sulfuric acid, hydrochloric acid, phosphoric acid, boric acid, inorganic acid salts of amino acids, organic acid salts of amino acids, inorganic acid salts of acylamino acids, organic acid salts of acylamino acids, and metal salts of inorganic acids. A method for producing a hydrophobic powder according to any one of claims (1) to (6). (8) The amount of acidic substance added is 001 to 1O to the powder.
Claims (1) to (7) which are weight %
A method for producing a hydrophobic powder according to any one of paragraphs. (9) A method for producing a hydrophobic powder according to any one of claims (1) to (8), in which the reaction is carried out mechanochemically. (10) Claim No. (9) in which the reaction is carried out under heating.
A method for producing a hydrophobic powder as described in Section 1. (Margin below)