JP2920159B2 - Composition for coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention forms a high-hardness film comprising a novel polyborosilazane as an essential component and having excellent heat resistance, abrasion resistance, chemical resistance and corrosion resistance. The present invention relates to a coating composition to be obtained, and more particularly to a coating composition containing a specific polyborasilazane as an essential component.

[Conventional technology]

2. Description of the Related Art Conventionally, it has been widely practiced to coat a surface of a metal material or an inorganic material to improve heat resistance, wear resistance, and chemical resistance of the material. In particular, as a method of coating a metal material, a method of forming various coatings by plating, phosphoric acid treatment, or chromic acid treatment, or a coating method using a paint in which various organic polymer resins are mixed with pigments and additives as necessary. It has been known.

However, plating, phosphoric acid treatment, or chromic acid treatment poses a problem of environmental pollution due to the waste liquid, and the waste liquid treatment has a drawback that requires a great deal of labor and cost, and various organic polymer resin paints have heat resistance. Insufficient, 20
Many deteriorate at 0 ° C or higher, and few can be used at high temperatures of 300 ° C or higher.

As a method for solving these drawbacks, silicone-based coatings, polytitanocarbosilane-based coatings, and poly (disilyl) silazane polymers (Japanese Patent Publication No. 61-38933),
A method using a polymetallosilazane polymer (Japanese Patent Application No. 63-45913) has been proposed.

However, although silicone-based paints provide films with excellent heat resistance even in a high-temperature atmosphere of 200 ° C or higher, pinholes are likely to occur, and when the film thickness is increased to prevent the occurrence of pinholes, Cracks, blisters, or peeling may occur in the coating during firing. Since such a phenomenon is particularly remarkable in a temperature range F of 300 ° C. or more, when a silicone-based paint is used, it is necessary to reduce the crosslink density of the silicone resin. The difficulty arises.

In addition, polytitanocarbosilane-based paints are fired at low temperatures (40
(0 ° C. or lower), the surface hardness is not sufficient, and the raw material production process is complicated, and the production cost is high.

In addition, the method using a poly (disyl) silazane-based polymer requires a process of performing thermal decomposition in an inert atmosphere or vacuum at a high temperature of 750 ° C. or higher, which involves many difficulties in its workability. Similarly, there has been a report on a coating film of silicon nitride obtained from polysilazane, but cracks have occurred and a film having sufficient practical value has not been obtained (WSCobling et al, “Formation of Ceramic Composi
tions Utilizing Polymer Pyrolysis ", p.217-285, Mate
rials Science Research voll, Emergent Process Metho
ds For High-Technology Ceramics edited by RFDab
is et.al, Plenun Press NY).

In addition, the polymetallosilazane-based polymer, compared to the coating material, is excellent in heat resistance, abrasion resistance and chemical resistance, and has an advantage in that a film having a high surface hardness is provided. In the temperature range, polymetallosilazane is crystallized, and the volume shrinks with the crystallization, causing cracks and peeling.

[Problems to be solved by the invention]

It is an object of the present invention to provide a coating composition which overcomes the above-mentioned drawbacks of the prior art and is excellent in heat resistance, abrasion resistance and chemical resistance and provides a coating having a high surface hardness.

[Means for solving the problem]

According to the present invention, (1) (a) mainly the general formula (I): (Wherein, R ¹ , R ² , and R ³ each independently represent a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group,
Or a group other than these groups in which the portion directly connected to silicon or nitrogen in the formula is carbon, an alkylsilyl group, an alkylamino group, or an alkoxy group. However, it is at least one of R ¹ , R ² and R ³ or a hydrogen atom. And a part of silicon and / or a part of nitrogen constituting the main skeleton are represented by the following general formulas (i) and (i).
A polyborosilazane having a cross-linking component represented by (i), (iii) or (iv) bonded thereto, having a B / Si atomic ratio in a range of 0.01 to 3 and a total average molecular weight of 200 to 500,000.

(In the formula, R ⁴ is a hydrogen atom, a halogen atom, a carbon atom having 1 to 1
Having 20 alkyl groups, alkenyl groups, cycloalkyl groups, aryl groups, alkoxy groups, alkylamino groups,
A hydroxyl group or an amino group, R ⁵ is a residue bonded to the nitrogen atom of the group having a nitrogen atom among R ⁴ ,
In v), at least two of a total of six atoms consisting of three nitrogen atoms and boron atoms are used for crosslinking, and R ⁴ can be bonded to the remaining atoms. (B) a coating composition comprising at least a solvent.

The polyborosilazane used in the present invention is soluble in an organic solvent and has a high thermal decomposition yield.
It has the advantage that it is amorphous at a temperature of 00 ° C. or higher.

The first feature of the polyborosilazane, which is an essential component of the coating composition of the present invention, is that the B / Si atomic ratio is in the range of 0.01 to 3, preferably 0.05 to 2.

If the B / Si atomic ratio is less than 0.01, no significant effect of containing boron is observed, and the ceramics after thermal decomposition are subjected to crystallization of silicon nitride from around 1400 ° C, so that the coating film is peeled off and heat resistance is increased. Inferior. Conversely, if the B / Si atomic ratio exceeds 3, the thermally decomposed ceramics will develop at the high temperature due to the crystallization of the boron compound, causing the coating film to peel off, etc., thus achieving the intended object of the present invention. Can not do it.

The second feature of the polyborosilazane, which is an essential component of the coating composition of the present invention, has a number average molecular weight of 200 to 500,00.
0, preferably in the range of 500 to 10,000.

If the number average molecular weight is less than 200, a large amount of volatile components are generated in the thermal decomposition process, so the ceramic yield is low,
Uniform and good coating film cannot be obtained, and 500,000
Exceeding the range makes it difficult to apply the composition to the substrate, and significantly reduces workability, which is not desirable.

A third feature of the polyporosilazane, which is an essential component of the coating composition of the present invention, is that it has a main skeleton composed of the unit represented by the general formula (I) and a part of silicon constituting the main skeleton. And / or a part of the nitrogen is bonded with the cross-linking component represented by the general formula (i), (ii), (iii) or (iv).

The polyborosilazane used in the present invention is, for example, a compound represented by the general formula (I) (Wherein, R ¹ , R ² , and R ³ each independently represent a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group,
Or a group other than these groups in which the portion directly connected to the silicon or nitrogen atom in the formula is carbon, an alkylsilyl group, an alkylamino group, or an alkoxy group. Where R ¹ , R ² ,
At least one of R ³ or a hydrogen atom. The compound is obtained by reacting a boron compound with a polysilazane having a main skeleton composed of the unit represented by the following formula and having a number average molecular weight of about 100 to 50,000.

In this case, examples of the alkyl group in the general formula (I) include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and decyl, and examples of the alkenyl group include vinyl, allyl, butenyl, pentenyl, and hexenyl. , Heptynyl, octel, decenyl and the like, and the aryl group includes phenyl, tolyl, xylyl, naphthyl and the like.

Specific examples of those preferably used as the above polysilazane are represented by the general formula And a cyclic inorganic polysilazane having a number average molecular weight of 100 to 50,000, a chain inorganic polysilazane or a mixture thereof.

When such a polyperhydrosilazane is used as a starting material, a polyborosilazane containing silicon and nitrogen as essential components and hydrogen as an optional component can be produced.

Such a polysilazane can be obtained, for example, by reacting an adduct of dichlorosilane and a base obtained by reacting a halosilane, for example, dichlorosilane with a base such as pyridine, with ammonia. (See Japanese Patent Application No. 60-145903).

Further, polysiloxazan having repeating units of SiH ₂ NH and SiH ₂ O and having a degree of polymerization of 5 to 300, preferably 5 to 100 (JP-A-62-195024) can also be preferably used.

Further, the composition formula (RSiHNH) x [(RSiH) _{1 · 5} N]
_1-X (wherein, R represents an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, or a group other than these groups.
A group in which the atom immediately following Si is carbon, an alkylsilyl group,
Represents an alkylamino group, an alkoxy group, and 0.4
<X <1. )) (Japanese Patent Application No. 60-293472) can also be used.

As the boron compound, any of organic and inorganic boron compounds can be used. Alkoxides, alkylborons, alkenylborons, alkylaminoborons and the like as organic boron compounds, borane as inorganic boron compounds,
Examples include boron halides and aminoborons.

The boron compound preferably used in the present invention is a compound represented by the following general formulas (II), (IV) and (V).

B (R ⁴ ) ₃ (II) B (R ⁴ ) ₃ ) · L (V) (wherein R ⁴ may be the same or different,
A hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group, a cycloalkyl group, an aryl group, an alkoxy group, an alkylamino group, a hydroxyl group or an amino group, and L is B (R ⁴ ) ₃ Is a compound that forms a complex with Hereinafter, specific compounds thereof will be exemplified.

Examples of B (R ⁴ ) ₃ (II) having a halogen atom as R ⁴ include fluoroborane, tribromoborane,
Trifluoroborane, trichloroborane, difluoroborane, diiodoborane, iodoborane, dibromomethylborane, dichloromethylborane, difluoromethylborane, difluoromethoxyborane, diiodomethylborane, ethynyldifluoroborane, difluorovinylborane, dibromoethylborane, dichloroethylborane , Dichloroethoxyborane, ethyldifluoroborane, ethyldiiodoborane, bromodimethylborane, dibromo (dimethylamino) borane, chlorodimethylborane, chlorodimethoxyborane, fluorodimethylborane, fluorodimethoxyborane, dichloroisopropylborane,
Dichloropropylborane, difluoropropoxyborane, bromo (dimethylamino) methylborane, chlorodivinylborane, dibromobutylborane, butyldichloroborane, butyldifluoroborane, butoxydifluoroborane, butoxydifluoroborane, bromodiethylborane, dibromo (diethylamino) borane, chloro Diethylborane, chlorodiethoxyborane, dichloro (pentafluorophenyl) borane, dichloro (diethylamino) borane, (diethylamino) difluoroborane, bromobis (dimethylamino) borane, chlorobis (dimethylamino) borane, bis (dimethylamino) fluoroborane, Dibromophenyl borane, dichlorophenyl borane, difluorophenyl borane, difluorophenokiborane, diiodoff Niruboran, dibromo (1,3-dimethyl-1-butenyl) borane, dibromo (3,3-dimethyl-1-butenyl) borane, dibromo (1-ethyl -
1-butenyl) borane, dibromo-1-hexenylborane, dibromo (2-methylcyclobenzyl) borane, 2
-Methylcyclopentyl-dichloroborane, dibromohexylborane, dibromo (2-methylpentyl) borane, difluorotoxylborane, dibromo (dipropylamino) borane, chlorodipropylborane, chloro (1,
1,2-trimethylpropyl) borane, dichloro (diisopropylamino) borane, butyl (dimethylamino) fluoroborane, dichloro (4-methylphenyl) borane, dichloro (methylphenylamino) borane, bromo (dimethylamino) phenylborane, chloro (Dimethylamino) phenylborane, 9-bromo-9-borabicyclo [3,3,1] nonane, 9-chloro-9-borabicyclo [3,3,1] nonane, diethylaminochloro- (1-butenyloxy) borane, dichloro Octylborane, bromobis (1-methylpropyl) borane, bromodibutylborane, dibromo (dibutylamino) borane, chlorobis (2-methylpropyl) borane, dibutylchloroborane, dichloro (dibutylamino) borane, dibutylfluoroborane, bromobis (diethyl) Lamino) borane, chlorobis (diethylamino) borane, dichloro (2,4,6
-Trimethylphenyl) borane, 3-bromo-7-methyl-3-borabicyclo [3,3,1] nonane, (diethylamino) chloro (cyclopentenyloxy) borane, dichloro (1,2,3,4,5-pentamethyl) -2,4-cyclopentadien-1-yl) borane, dibromo (1,2,3,4,5-pentamethyl-2,4-cyclopentadien-1-yl) borane, diiod (1,2,3,4 , 5-pentamethyl-2,4-cyclopentadien-1-yl) borane, chlorodicyclopentylborane, chloro (diethylamino) phenylborane, bromodicyclopentylborane, (1-butyl-1
-Hexenyl) dichloroborane, bromodipentylborane, chlorodiphenylborane, bromodiphenylborane, dichloro (diphenylamino) borane, chloro (diisopropylamino) phenylborane, chloro (dipropylamino) phenylborane, bromobis (2-bromo-1-) Hexenyl) borane, chlorobis (2-chloro-
1-hexenyl) borane, chlorodicyclohexylborane, chlorodi-1-hexenylborane, chloro (1-ethyl-1-butenyl) (1,1,2-trimethylpropyl)
Borane, chloro-1-hexenyl (1,1,2-trimethylpropyl) borane, [methyl (4-bromophenyl) amino] chloro (phenyl) borane, chloro (2-phenylethynyl) (1,1,2-trimethyl Propyl) borane,
Chloro (dibutylamino) phenylborane, chlorooctyl (1,1,2-trimethylpropylborane, chlorobis (dibutylamino) borane, fluorobis (2,4,6-trimethylphenyl) borane, (1-bromo-1-hexenyl) ) Bis (2-methylpentyl) borane, (1-bromo-1-hexenyl) dihexylborane, bis (1-butyl-1-hexenyl) chloroborane, (5-chloro-
1-pentenyl) bis (1,2-dimethylpropyl) borane;

Examples of R ⁴ having an alkoxy group include dihydroxymethoxyborane, dimethoxyborane, methoxydimethylborane, methyldimethoxyborane, trimethoxyborane, ethyldimethoxyborane, dimethylaminomethoxymethylborane, (dimethylamino) dimethoxyborane, Diethylmethoxyborane, dimethoxypropylborane, bis (dimethylamino) methoxyborane, ethoxydiethylborane, butyldimethoxyborane, diethoxyethylborane, triethoxyborane, cyclopentyldimethoxyborane, methoxydipropylborane, dimethoxyphenylborane, (2- Methylcyclopentyl)
Dimethoxyborane, butoxydiethylborane, ethoxydipropylborane, hexyldimethoxyborane, 3-methoxy-3-borabicyclo- [3,3,1] nonane, 9-methoxy-9-borabicyclo [3,3,1] nonane, dibutyl Methoxyborane, methoxybis (1-methylpropyl)
Borane, methoxybis (2-methylpropyl) borane,
Propoxydipropyl borane, triisopropoxy borane, tripropoxy borane, butoxydipropyl borane, dibutyl ethoxy borane, diethyl (hexyloxy) borane, dibutoxyethyl borane, di-tert-butoxyethyl borane, dicyclopentyl methoxy borane,
Dibutylpropoxyborane, ethoxydipentylborane, (hexyloxy) dipropylborane, tributoxyborane, tri-tert-butoxyborane, tris (2-
Butoxy) borane, tris (2-methylpropoxy) borane, methoxydiphenylborane, dicyclohexyl (methoxy) borane, dibutyl (2-penten-3-yloxy) borane, dibutoxypentylborane, ethoxydiphenylborane, (2-aminoethoxy) Diphenoxyborane, dibutyl (1-cyclohexenyloxy) borane, butoxydipentylborane, dibutyl (hexyloxy) borane, dibutoxyhexylborane, dihexyloxypropylborane, tripentyloxyborane,
Butoxydiphenylborane, (2-methylpropoxy)
Diphenylborane, diphenoxyphenylborane, triphenoxyborane, tricyclohexyloxyborane,
Methoxybis (2,4,6-trimethylphenyl) borane,
Examples include tribenzyloxyborane, tris (3-methylphenoxy) borane, trioctyloxyborane, trinonyloxyborane, trioctadecyloxyborane, and the like.

Examples of those having an alkenyl group as R ⁴ include ethynyl borane, vinyl borane, dihydroxy vinyl borane, 2-propenyl borane, ethynyl dimethoxy borane, methyl divinyl borane, trivinyl borane, 1-hexenyl dihydroxy borane, dimethoxy (3-methyl 1,2-butadienyl) borane, diethyl-2-propenylborane, dihydroxy (2-phenylethenyl) borane, (diethylamino) diethynylborane,
Diethylaminodi-1-propylnylborane, 2-butenyldiethylborane, diethyl (2-methyl-2-propenyl) borane, bis (dimethylamino) (1-methyl-2-propenyl) borane, 2-butenylbis (dimethylamino) ) Borane, tri-2-propenylborane, tri (2-propenyloxy) borane, diethyl (3-methyl-2-butenyl) borane, 2-propenyldipropylborane, (diethylamino) di-1-propynylborane, butyl- Di-2-propenylborane, 2-butenyldipropylborane, diethyl (1-ethyl-2-butenyl) borane, (2-methyl-2-propenyl) dipropylborane, diethyl (1,1-dimethyl-3-) Butene-1
-Yloxy) borane, diethyl (1-hexene-4-)
Yloxy) borane, 9- (2-propenyl) -9-borabicyclo [3,3,1] nonane, dibutyl-2-propenylborane, (3-methyl-2-butenyl) dipropylborane, 9 (2-butenyl) -9-borabicyclo [3,3,
1] nonane, tri-2-butenylborane, tris (2-
Methyl-2-propenyl) borane, hexyldi-2-propenylborane, 2-butenyldibutylborane, bis (1,2-dimethylpropyl) (2-phenylethenyl)
And borane, bis (1,2-dimethylpropyl) -1-octenylborane and the like.

Examples of R ⁴ having an alkylamino group or an amino group include aminoborane, diaminoborane, aminodimethylborane, (dimethylamino) borane, dimethyl (methylamino) borane, methylbis (methylamino) borane, and tris (methylamino) borane. , (Dimethylamino) dimethylborane, bis (dimethylamino) borane,
Bis (dimethylamino) methylborane, aminodipropylborane, (diethylamino) dimethylborane, (dimethylamino) diethylborane, tris (dimethylamino) borane, isopropylbis (dimethylamino) borane, dimethyl (phenylamino) borane, bis (methyl) Amino) phenylborane, bis (dimethylamino) -1
-Pyrrolylborane, aminodibutylborane, diethylborane, dimethylaminodipropylborane, bis (dimethylamino) phenylborane, dibutyl (dimethylamino) borane, di-tert-butyl (dimethylamino) borane, dibutyl (diethylamino) borane, tris (Diethylamino) borane, dimethylaminophenylborane,
Aminobis (2,4,6-trimethylphenyl) borane;

Examples of R ⁴ having a hydroxyl group include boric acid, hydroxy borane, dihydroxy (methyl) borane, hydroxydimethyl borane, ethyl dihydroxy borane, dihydroxy propyl borane,
Furanyl dihydroxy borane, diethyl hydroxy borane, butyl dihydroxy borane, cyclopentyl dihydroxy borane, pentyl dihydroxy borane, (3-aminophenyl) dihydroxy borane, phenyl hydroxy borane, heptyl hydroxy borane, Examples thereof include dihydroxy (2-phenylethyl) borane, dihydroxy (1-naphthalenyl) borane, hydroxybis (2,4,6-trimethylphenyl) borane, and hydroxydiphenylborane.

Examples of those having an alkyl group as R ⁴ include methyl borane, dimethyl borane, ethyl borane, trimethyl borane, diethyl borane, ethyl dimethyl borane, diethyl methyl borane, 3-methyl-2-butyl borane, triethyl borane, (1,1,2- Trimethylpropyl) borane,
Dibutylborane, triisopropylborane, tripropylborane, bis (3-methyl-2-butyl) borane, bis (1,1,2-trimethylpropyl) borane, tri-tert
-Butylborane, tributylborane, tris (1-methylpropyl) borane, tris (2-methylpropyl) borane, tris (2-methylpropyl) borane, tripentylborane, tris (1,2-dimethylpropyl) borane, trihexyl Borane, trioctylborane, and the like.

As those having a cycloalkyl group as R ⁴ , cyclopentyl borane, cyclohexyl borane, dicyclohexyl borane, cyclohexyl (1,1,2-trimethylpropyl) borane, tricyclopentyl borane, tricyclohexyl borane, those having an aryl group as R ⁴ Are tri-1-naphthylborane, tris (2,4,6
-Trimethylphenyl) borane, tribenzylborane,
Tris (4-methylphenyl) borane, triphenylborane, phenylborane, ethyldiphenylborane and the like can be mentioned.

Examples of those having a hydrogen atom as R ⁴ include borane.

As, 2,4,6-trichloroborazine, 2,4,6-tribromoborazine, 2,4,6-trifluorofluoroborazine, holazine, 1-methylborazine, 2,4,6-trichloro-1, 3,5-
Trimethylborazine, 2,4,6-tribromo-1,3,5-trimethylborazine, 2,4,6-trifluoro-1,3,5-trimethylborazine, 1,3,5-trimethylborazine, 2,4 , 6-Trimethylborazine, 2,4,6-trimethoxyborazine, 2,4
-Dichloro-1,3,5,6-tetramethylborazine, 2-chloro-1,3,4,5,6-pentamethylborazine, 2,4,6-trichloro-1,3,5-trichloro-1 , 3,5-Triethylborazine, hexamethylborazine, 1,3,5-tritylborane, 2,4,6-triethylborane, 1,3,5-olipropylpropylazine, 2,4,6-triethyl-1 , 3,5-trimethylborandine, 1,3,5-tribryl-2,4,6-trichloroborazine, hexaethylborazine, 2,4,6-trichloro-1,3,5
-Triphenylborazine, 2,4,6-triphenylborazine, 2,4,6-tri (diethylamino) borazine, 2,4,6-
Tri (bis (trimethylsilyl) amino) borazine, 2,
4,6-tris (dimethylamino) 1,3,5-trimethylborazine, 1,3,5-trimethyl-2,4,6-triphenylborazine and the like can be mentioned.

B (R ⁴ ) ₃ : L (V) includes borane-phosphine, borane-hydrazine, trifluoroborane-methanol, cyanoborane-ammonia, difluoroborane-methylamine, borane-methylamine, tribromoborazine-dimethylsulphate , Trichloroborane-dimethyl sulfide, trifluoroborane-dimethyl ether, trifluoroborane-ethanol, borane-isocyanomethane, dibromoborane-dimethylsulfide,
Dichloroborane-dimethylsulfide, tochloroborane-dimethylamine, trifluoroborane-ethylamine, dianoborane-methylamine, bromoborane-dimethylsulfide, chloroborane-dimethylsulfide, difluoroborane-dimethylamine, iodoborane-dimethylsulfide, chloroborane-dimethylamine, borane- Dimethylamine, borane-dimethylphosphine, tribromoborane-trimethylphosphine,
Tribromoborane-trimethylamine, trichloroborane-trimethylamine, trichloroborane-trimethylphosphine, trifluoroborane-trimethylamine, trifluoroborane-trimethylphosphine, triiodoborane-trimethylphosphine, dianoborane-dimethylamine, difluoroborane-trimethylamine, bromoborane- Trimethylphosphine, chloroborane-trimethylphosphine, fluoroborane-trimethylamine, iodoborane-trimethylamine, iodoborane-trimethylphosphine, borane-trimethylamine, trimethylborane-ammonia, trimethoxyborane-ammonia, borane-trimethylphosphite, borane-trimethylphosphite Fin, trifluorofluoroborane-2-methyl Imidazole, trifluoroborane - tetrahydrofuran, chloroborane - tetrahydrofuran, trichloroborane - diethyl ether, trifluoroborane - diethyl ether, dibromo borane - diethyl ether, dichloroborane - diethyl ether,
Dianoborane-trimethylamine, bromoborane-diethylether, dibromoborane-trimethylamine, dibromomethylborane-trimethylphosphine, chloroborane-diethylether, borane-tert-butylamine, boranedi-diethylamine, tribromoborane-pyridine, trichloroborane-pyridine, trifluoroborane Run-pyridine, borane-pyridine, borane-4-aminopyridine, bromodimethylborane-trimethylphosphine, dichlorocyanoborane-pyridine, trifluoroborane-phenol, cyanoborane-pyridine, dibromomethylborane-pyridine, borane-4-methyl Pyridine, trifluoroborane-1-hexanol, tribromoborane-triethylamine, trichloroborane-triethylamine, Loloborane-triethylamine, borane-triethylamine, trimethylborane-trimethylamine, borane-tris (dimethylamino) phosphine, trifluoroborane-methoxybenzene, trifluoroborane-4-methylaniline, borane-2,6-dimethylpyridine, trifluoroborane- Dibutyl ether,
Phenyldichloroborane-triethylamine, tribromoborane-triphenylphosphine, trichloroborane-triphenylphosphine, trifluoroborane-
Examples thereof include triphenylphosphine, borane-triphenylamine, borane-triphenylphosphine, trimethylborane-triphenylamine, triphenylborane-trimethylamine, triphenylborane-pyridine, and triphenylborane-triethylamine. In addition to the above substances, tetraborane (10), pentaborane (9), pentaborane (11), hexaborane (1
0), hexaborane (12), octaborane (12), octaborane (18), isononaborane (15), nonaborane (15), decaborane (14), 1,1'-pipentaborane (9), 1,2'-pipetaborane ( 9), 2,2'-pipentaborane (9), 1-carbahexaborane (7), 2-carbahexaborane (9), 1,2-dicarbahexaborane (6), 1,2-dicarbapenta Borane (7), 2,4-dicarbaheptane borane (7), 2,3-dicarbahexaborane (8), 1,7-dicarbaoctaborane (8), 1,2-dicarbadodecaborane ( Good results can also be obtained using 12), 1,7-dicarbadodecaborane (12) and 1,12-dicarbadodecaborane (12).

Although most of these boron compounds are commercially available, even those that are not commercially available can be produced by a method similar to that of commercially available products.

The mixing ratio of the polysilazane and the boron compound is adjusted so that the B / Si atomic ratio becomes 0.01 to 3, preferably 0.05 to 2, and more preferably 0.1 to 1. If the boron compound is added in an amount larger than this, the boron compound is simply recovered without being reacted without increasing the reactivity with the polysilazane.

The reaction can be carried out without a solvent, but it is more difficult to control the reaction than when an organic solvent is used, and a gel-like substance may be formed. Therefore, it is generally preferable to use an organic solvent.

As the reaction solvent, a solvent that does not show reactivity with polysilazane and boron compound is used. As such a non-reactive solvent, hydrocarbons, halogenated hydrocarbons, ethers, sulfur compounds and the like are used.

The reaction temperature and pressure are not particularly limited, but the reaction temperature is preferably lower than the boiling point of the reaction solvent and the boron compound.

In the present invention, in order to form a coating composition using the polyborosilazane, the polyborosilazane may be dissolved in a solvent. Examples of the solvent include aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbon solvents, halogenated hydrocarbons such as halogenated methane, halogenated ethane, and halogenated benzene, aliphatic ethers, alicyclic ethers. And the like. Preferred solvents are methylene chloride, chloroform, carbon tetrachloride, bromoform, ethylene chloride, ethylidene chloride, trichloroethane, halogenated hydrocarbons such as tetrachloroethane,
Ethyl ether, isopropyl ether, ethyl butyl ether, butyl ether, 1,2-dioxyethane, siloxane, dimethyldioxane, tetrahydrofuran,
Ethers such as tetrahydropyran; and hydrocarbons such as pentanehexane, isohexane, methylpentane, heptane, isoheptane, octane, isooctane, cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane, benzene, toluene, xylene, and ethylbenzene.

When these solvents are used, two or more kinds of solvents may be mixed in order to adjust the solubility of the polyborosilazane and the evaporation rate of the solvent.

The amount of solvent used (proportion) is selected so as to improve the workability by the coating method, and the average molecular weight, molecular weight distribution and structure of polyborosilazane vary. Therefore, the solvent in the coating composition is about 90% by weight. And preferably in the range of 10 to 50% by weight.

The average molecular weight of the solvent concentration leaf raw material polyborosilazane,
Good results are usually obtained in the range of 0 to 90% by weight, although it depends on the molecular weight distribution and its structure.

In the present invention, a suitable filler may be added as needed. Examples of the filler include fine powders of oxide-based inorganic substances such as silica, alumina, zirconia, and mica, and non-oxide-based inorganic substances such as silicon carbide and silicon nitride. Depending on the application, metal powder such as aluminum, zinc, and copper can be added. Further examples of fillers include silica silica, quartz, novacurite, diatomaceous earth, and other silica-based materials: synthetic amorphous silica: kaolinite, mica, talc, wollastonite, asbestos, calcium silicate, aluminum silicate Glass bodies such as glass powder, glass spheres, hollow glass spheres, glass flakes, foam glass spheres: boron nitride, boron carbide, aluminum nitride, aluminum carbide, silicon nitride, silicon carbide, titanium boride, nitride Non-oxide inorganic substances such as titanium and titanium carbide: calcium carbonate: zinc oxide,
Metal oxides such as alumina, magnesia, titanium oxide and beryllium oxide: barium sulfate, molybdenum disulfide, tungsten disulfide, carbon fluoride and other inorganic substances: metal powders such as aluminum, bronze, lead, stainless steel, zinc, etc .: carbon black, Examples include carbon bodies such as coke, graphite, pyrolytic carbon, and hollow carbon spheres.

These fillers can be used alone or in a mixture of two or more in various shapes such as needle-like (including whisker) powder-like and scale-like. Further, it is desirable that the particle size of these fillers is smaller than the film thickness that can be applied at one time. The addition amount of the filler is in the range of 0.05 part by weight to 10 parts by weight based on 1 part by weight of polyborosilazane, and the particularly preferable addition amount is in the range of 0.2 part by weight to 5 parts by weight. Further, the surface of the filler may be surface-treated by coupling agent treatment, vapor deposition, plating or the like before use.

In the coating composition, various pigments as necessary,
Leveling agent, defoamer, antistatic agent, ultraviolet absorber, PH
Adjusters, dispersants, surface modifiers, plasticizers, drying accelerators, flow inhibitors may be added.

The coating composition of the present invention prepared as described above is uniformly dissolved and decomposed to be coated on a base such as metal, ceramics, and plastics. As a coating means as a coating, a usual coating method, that is, dipping, roll coating, bar coating, brush coating, spray coating, flow coating or the like is used. In addition, if the substrate is sanded, degreased, or surface-treated with various types of blasting before application, the adhesion performance of the coating composition is improved. After coating by such a method and sufficiently drying, heating and baking are performed. By this baking, the polyborosilazane is crosslinked, condensed and hardened to form a tough coating.

The above sintering conditions vary depending on the molecular weight and structure of polysilazane, but at a gentle heating rate of 3 ° C./min.
Firing at a temperature in the range Preferred firing temperature is 800 ° C ~ 1
It is in the range of 700 ° C.

〔effect〕

Since the coating composition of the present invention contains the above-mentioned polyborosilazane as an essential component, it is easy to handle, has excellent heat resistance, thermal shock resistance, corrosion resistance, and easily forms a silicon nitride coating film having high hardness. can do.

Therefore, it can be used even under extremely severe conditions that cannot be used with conventional organic polymer-based paints, silicone resin-based paints, polysilazane-based paints, polytitanocarbosilane-based paints, and polymetallosilazane-based paints. Can be applied to applications.

〔Example〕

 Hereinafter, the present invention will be described in more detail with reference to examples.

Reference Example 1 A four-necked flask having an internal volume of 1 was equipped with a gas blow-in tube, a mechanical stirrer, and a dewar condenser.
After the inside of the reactor was replaced with deoxygenated dry nitrogen, 490 ml of degassed dry pyridine was placed in a four-necked flask, and cooled with ice. Next, when 51.6 g of dichlorosilane was added, a white solid adduct (SiH ₂ Cl ₂ .2C ₃ H ₆ N) was formed. The reaction mixture was ice-cooled, and while stirring, 51.0 g of purified ammonia was blown through a sodium hydroxide tube and an activated carbon tube.

After completion of the reaction, the reaction mixture was centrifuged, washed with dry pyridine, and then filtered under a nitrogen atmosphere to obtain 850 ml of a filtrate. The solvent was distilled off from 5 ml of the filtrate under reduced pressure to obtain 0.102 g of a resin solid perhydropolysilazane.

The number average molecular weight of the obtained polymer was 980 as measured by GPC. When the IR (infrared absorption) spectrum (solvent: dry o-xylene; concentration of perhydropolysilazane: 10.2 g / l) of this polymer is examined, the wave number (cm ⁻¹ ) is 3350 (apparent absorption coefficient ε = 0.557). lg ¹¹ cm ^-1 )
And an absorption based on NH of 1175; an absorption based on SiH of 2170 (ε = 3.14); and an absorption based on SiH and SiNSi of 1020 to 820. When the ¹ H NMR (proton nuclear magnetic resonance) spectrum (60 MHz, solvent CDCl ₂ / standard substance TMS) of this polymer was examined, it was confirmed that all of the polymers showed broad absorption. That is, δ 4.8 and 4.4 (br, SiH); 1.5
(Br, NH) absorption was confirmed.

600 ml of the obtained pyridine solution of perhydropolysilazane (concentration of perhydropolysilazane: 5.20% by weight) and 30 ml (0.254 mol) of trimethyl borate were placed in an autoclave having an internal volume of 1, and the mixture was stirred at 160 ° C. for 3 hours to react. . After cooling to room temperature, 500 ml of dry o-xylene was added,
After removing the solvent at a pressure of 3 to 5 mmHg and a temperature of 50 to 70 ° C,
Polyborosilazane 38 having a number average molecular weight of 2100 as a white solid
g was obtained.

Reference Example 2 A reaction was carried out using the same apparatus as in Reference Example 1. That is,
450 ml of degassed dry tetrahydrofuran was placed in the four-necked flask shown in Reference Example 1, and cooled in a dry ice-methanol bath. Next, 46.2 g of dichlorosilane was added. The solvent is cooled and stirred with anhydrous methylamine.
44.2 g was blown as a mixed gas with nitrogen.

After completion of the reaction, the reaction mixture was centrifuged, washed with dry tetrahydrofuran, and further filtered under a nitrogen atmosphere to obtain 820 ml of a filtrate. The solvent was distilled off under reduced pressure to obtain 8.4 g of viscous oily N-methylsilazane. The number average molecular weight of the obtained polymer was 1100 as measured by GPC.
Met.

The resulting N-methylsilazane γ-pyrroline solution (N-
600 ml of methylsilazane (8.60% by weight) and 130 mol (0.482 mol) of tributyl borate were placed in an autoclave having an internal volume of 1, and the reaction was carried out at 160 ° C. for 5 hours with stirring. When the solvent was distilled off under reduced pressure in the same manner as in Reference Example 1, 48 g of polyborosilazane having a number average molecular weight of 1880 as a pale yellow solid was obtained.
Obtained.

Reference Example 3 A four-necked flask having an internal volume of 1 was equipped with a gas blow-in tube mechanical stirrer and a dewar condenser. After the inside of the reactor was replaced with deoxygenated dry nitrogen, 300 ml of dry dichloromethane and 24.3 g (0.211 mol) of methyldichlorosilane were placed in a four-necked flask and cooled with ice. While stirring, 18.1 g (1.06 mol) of purified ammonia was blown through a sodium hydroxide tube and an activated carbon tube.

After completion of the reaction, the reaction mixture was centrifuged, washed with dry dichloromethane, and filtered under a nitrogen atmosphere. The solvent was distilled off from the filtrate under reduced pressure to obtain 8.81 g of colorless and transparent methyl (hydro) silazane. The number average molecular weight of this product was 380 as measured by GPC.

Obtained o-xylene solution of methyl (hydro) silazane (concentration of methyl (hydro) silazane: 6.40% by weight) 300
ml into a 14-neck flask, ice-cooled, and mixed with boron trichloride.
After adding 50 g (0.427 mol) over 2 hours, add 2 g
The reaction was carried out by stirring at 5 ° C. for 3 hours. 200 ml in this solution
Of 1,1,1-3,3,3 hexamethyldisilazane was added and stirred at 80 ° C. for 3 hours to produce a precipitate. The precipitate was filtered and the filtrate was evaporated under reduced pressure to give 58 g of a pale yellow solid, polyborosilazane having a number average molecular weight of 4,800.

Reference Example 4 A four-necked flask having an internal volume of 1 was equipped with a drop coat, a condenser, a mechanical stirrer, and a gas injection tube. After replacing the inside of the reactor with deoxygenated dry nitrogen, 4
200 ml of dry chlorobenzene and 50 g of boron trichloride were placed in a one-necked flask, and this was cooled with ice. Next, 17 g of dry acetonitrile was added dropwise, and a white solid adduct (CH ₃ CN ・ BC
l ₃ ) generated. After the addition was completed, 22 g of ammonium chloride dried at 110 ° C. was added. The reaction mixture was heated under reflux for 5 hours to obtain a colorless and transparent solution. After cooling to room temperature, 45 ml of diethylamine were added dropwise. After completion of the reaction, the mixture was filtered under a nitrogen atmosphere to remove the solvent of the filtrate.
-21 g of tris (diethylamino) borazine were obtained.

Pyridine solution of perhydropolysilazane obtained in Reference Example 1 (concentration of perhydropolysilazane; 4.70% by weight) 6
B-tris (diethylamino) borazine obtained with 00 ml
55 g (0.187 mol) was placed in an autoclave having an internal volume of 1, and the reaction was carried out at 80 ° C. with stirring for 2 hours. After cooling to room temperature, the solvent was distilled off under reduced pressure in the same manner as in Reference Example 1.
Polyborosilazane 64 having a number average molecular weight of 2800 as a white solid
g was obtained.

Example Using the polyborosilazane obtained in Reference Examples 1 to 4, the respective components were mixed in the composition shown in Tables 1 to 4 to obtain a composition for silicon nitride coating.

The obtained coating composition is applied to a carbon plate (glassy carbon) of 20 mm x 40 mm x 2 mm and baked under a nitrogen atmosphere at 600 to 1750 C for 1 hour to form a silicon nitride coating with a thickness of 30 m. A film was formed.

The pencil hardness and adhesion (base peel test) of the silicon nitride coating film were measured according to the following inspection methods. The results are shown in Tables 1 to 4.

(A) Pencil hardness: according to JIS K5400.

(B) Base peel test (adhesion): Use a steel knife on the coating film
Make 100 cuts at the base of 1mm square material, glue cellophane tape (Sekisui Chemical Co., Ltd.) on it, and leave the cellophane tape strongly peeled upward 90 ° Evaluate by the number of eyes.

Continued on the front page (72) Inventor Nao Suzuki 1-3-1, Nishitsurugaoka, Oimachi, Iruma-gun, Saitama Prefecture Inside Tonen Co., Ltd. (72) Inventor Yuji Tashiro 1-3-3, Nishitsurugaoka, Oimachi, Iruma-gun, Saitama No. 1 Tonen Research Institute (72) Inventor Kiyoshi Sato 1-3-1 Nishitsurugaoka, Oi-machi, Iruma-gun, Saitama Prefecture No. 1 Tonen Research Institute (72) Inventor Takeshi Isoda Nishi-Tsurugaoka, Oi-machi, Iruma-gun, Saitama 1-3-1 No. 1 in Tonen Research Laboratory (56) References JP-A 1-252638 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C09D 183/16 C09D 185 / 04

Claims (1)

(57) [Claims] (A) A compound represented by the general formula (I): (Wherein, R ¹ , R ² , and R ³ each independently represent a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group,
Or a group other than these groups in which the portion directly connected to silicon or nitrogen in the formula is carbon, an alkylsilyl group, an alkylamino group, or an alkoxy group. However, at least one of R ¹ , R ² and R ³ is a hydrogen atom. And a part of silicon and / or a part of nitrogen constituting the main skeleton are represented by the following general formulas (i) and (i).
A polyborosilazane having a cross-linking component represented by (i), (iii) or (iv) bonded thereto, having a B / Si atomic ratio in a range of 0.01 to 3 and a number average molecular weight of 200 to 500,000. (In the formula, R ⁴ is a hydrogen atom, a halogen atom, a carbon atom having 1 to 1
Having 20 alkyl groups, alkenyl groups, cycloalkyl groups, aryl groups, alkoxy groups, alkylamino groups,
A hydroxyl group or an amino group, R ⁵ is a residue bonded to the nitrogen atom of the group having a nitrogen atom among R ⁴ ,
In v), at least two of a total of six atoms consisting of three nitrogen atoms and boron atoms are used for crosslinking, and R ⁴ can be bonded to the remaining atoms. (B) A coating composition containing at least a solvent.