JPH0351758B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a mold release or lubricating composition containing boron nitride powder as a main ingredient, which has excellent heat resistance and wear resistance. (Prior art and problems) Conventionally, when boron nitride is used as a mold release/lubricant agent, it is suspended in water or a solvent, and applied to various base materials by spraying or brushing.
Alternatively, this has been done by spreading boron nitride powder itself on the surface of the base material. Moreover, the boron nitride powder can be released from the mold. When used as a lubricant, the powder has poor adhesion to the substrate, and coatings formed by conventional methods tend to release after one or several uses. The disadvantage is that the lubricating effect is lost, resulting in unsatisfactory use, and therefore frequent application is required. Even if the powder is kneaded with resin, oil, etc. as a countermeasure, this alone will not improve the drawback that it is difficult to blend into the base material. As a method for improving the adhesion with this base material, examples include using additives such as carboxymethyl cellulose and sodium lignin sulfonate, and additive aids such as water glass and phosphates (Japanese Patent Laid-Open No. 55-29506 ),
Example using monoaluminum phosphate (Unexamined Japanese Patent Publication No. 1983-
145131). (Problems to be solved by the invention) However, these methods have problems in workability because they use strongly acidic or strongly alkaline materials, and are also corrosive to the base material and cause precipitation over time. However, there are also problems in maintaining storage stability due to the occurrence of oxidation, and improvements in these problems have been desired. (Means for Solving the Problems) The present invention was made as a result of various studies to improve these drawbacks, and its gist is that the following general formula is applied to 100 parts by weight of boron nitride powder.
A boron nitride-containing mold release or lubricant composition is provided by dispersing and dissolving 10 to 150 parts by weight of the organosilicon compounds (1) to (3) and 1 to 10 parts by weight of a surfactant in an organic solvent. There is a particular thing. The boron nitride-containing composition obtained by the present invention itself has excellent storage stability, and the film formed by applying it to a substrate and drying or baking it,
By improving its strength and adhesion to the base material, it is easier to release the mold. The duration as a lubricant is improved,
Work efficiency can be significantly improved. To explain this in detail below, the organosilicon compound used in the present invention has the general formula: (Here, R ¹ is an atom or group selected from a hydrogen atom or an unsubstituted or substituted monovalent hydrocarbon group, and a and b are 0<a<2, 0.001<b<
0.5) silicone varnish with an undetermined molecular weight, manufactured by Shin-Etsu Chemical Co., Ltd., KR230B, KR311,
KR5221 etc. are exemplified. (Here, R ² and R ³ are hydrogen atoms or atoms or groups selected from the same or different unsubstituted or substituted monovalent hydrocarbon groups, and c and d are 0<
A polysilazane polysiloxane with an indefinite molecular weight, where c, d<2, m, n are m≧1, n≧0. 3 R ⁴ _e Si(OR ⁵ ) _4-e (where R ⁴ is a group selected from unsubstituted or substituted monovalent hydrocarbon groups, R ⁵ is a saturated unsubstituted or substituted monovalent hydrocarbon group, e is 1, 2, 3
An ester silane (carbon functional silane) represented by a positive number selected from, for example, KBM-503 (γ-methacryloxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd.
Examples include KBM-403 (γ-glycidoxypropyltrimethoxysilane). Boron nitride powder was placed in an organic solvent. The organic silicon compound and surfactant are added to this suspension, and the mixture is thoroughly mixed using a powerful mixer such as a homogenizer. The mold release of the present invention is performed by dispersing the mold. A composition suitable for lubricant applications is obtained. The smaller the particle size of the boron nitride powder, the better its dispersibility and the more uniform a film can be obtained during baking, but in general, it is desirable to have a particle size of 20 μm or less, and the concentration can be adjusted according to the method of application. can be adopted. The amount of the organosilicon compound used is in the range of 10 to 150 parts by weight per 100 parts by weight of boron nitride powder. If it is less than 10 parts by weight, the effect will be poor, and if it is more than 150 parts by weight, the properties of boron nitride will be impaired. The surfactant is blended at a ratio of 1 to 10 parts by weight per 100 parts by weight of boron nitride powder, and the type of surfactant may be anionic, cationic, nonionic, or other, but specific examples include alkyl sulfonates and higher alcohols. Examples include sulfates, quaternary ammonium salts, ethylene oxide adducts of organic amines, ethylene oxide adducts of amides, and ethylene oxide adducts of fatty acids. The solvent is not particularly limited and may be any solvent as long as it is soluble in the organosilicon compound, and examples include dichloromethane, dichloroethane, diethyl ether, tetrahydrofuran, toluene, and xylene. The boron nitride-containing composition thus obtained is applied to a substrate by spraying, brushing, etc.
A film with good adhesion to the substrate is formed by heat treatment. (Function) The boron nitride-containing composition of the present invention has high heat resistance. It is a mixture of boron nitride powder, which has lubricating properties, and an organosilicon compound, which is chemically neutral and stable in addition to heat resistance and mold release properties.This is applied to a base material and dried. Alternatively, the coating formed by baking treatment exhibits the characteristics of both synergistically,
Compared to conventional methods, this method has superior adhesion to substrates, workability, durability, etc. Therefore, it can be used as an additive to engine oil and other lubricating oils, in addition to applications such as aluminum die-casting molds and mold release agents in glass molding. In this case, it is also useful to dry the boron nitride-containing composition of the present invention to remove the organic solvent, and then add the powdered composition. (Example 1) Boron nitride powder 120g, trichloroethane 1080
Mix and suspend thoroughly. For each 50g of this stock solution, silicone varnish KR manufactured by Shin-Etsu Chemical Co., Ltd.
−230B, KR−311, modified silicone varnish KR−
5221 (Polyester modified silicone varnish), ES
-100IN (epoxy modified silicone varnish)
2.0g and surfactant Emazol L-10 manufactured by Kao Corporation
(Sorbitan monolaurate) 0.1 g was added to each sample and uniformly dispersed using a homogenizer to prepare samples. These samples were applied with a brush to a 0.3 mm iron test piece, air-dried, and then baked at 180°C for 30 minutes. The properties of these coatings are summarized in Table 1. In addition, KR-230B, KR-311, KR-5221, ES
-1001N are siloxanes with the following compositions. KR−23OB: CH ₃ SiO _3/2 ] ₉₇ [CH ₃ ] ₂ SiO _2/2 ] ₃ KR−311: [CH ₃ SiO _3/2 ] _22.8 [(CH ₃ ) ₂ SiO _2/2 ] _34.1

【formula】

[Formula] KR5221: Polyester modified silicone (50% modified) Polyester...Condensation product silicone of trimethylolethane and isophthalic acid...[CH ₃ SiO _3/2 ] _31.3

【formula】

[Formula] ES-1001N: Epoxy modified silicone (30% modified) Epoxy... Condensate silicone of bisphenol A and epichlorohydrin... [CH ₃ SiO _3/2 ] _19.0 [(CH ₃ ) ₂ SiO _2/2 ] _40.3

【formula】

[Formula] Next, 200 g of the above trichloroethane dispersion of boron nitride powder, with and without 10 g of ES-100lN added, were applied to the surface of a plaster mold with a brush and dried. A bare film was formed. Molten glass at 700 to 800°C was poured into these molds to create glass molded bodies. The state of the boron nitride coating after this glass molded body was removed from the mold was that without the addition of silicone varnish, the entire surface peeled off and could not be reused, whereas the coating on the mold with silicone varnish was stable. It could be reused up to 4 times. (Example 2) After adding 100 g of methyltrichlorosilane and 10 g of both-terminated dichloropolysiloxane (average molecular weight 2600) to 500 g of methylene chloride, ammonia glass was blown in while stirring at a temperature below 20°C to cause a reaction, until absorption disappeared. At this point, excess ammonia glass was discharged and the generated ammonium chloride was filtered off to obtain a polysilazane polysiloxane solution having a concentration of about 10%. 10 g of the polysilazane polysiloxane solution was added to 50 g of the same trichloroethane dispersion of boron nitride powder as in Example 1, and 0.1 g of the surfactant Naimeen S-215 (polyoxyethylene octadecylamine) manufactured by NOF Corporation was added. A coating treatment similar to that in Example 1 was carried out using a material to which g was added, and the film properties were measured. The results are also shown in Table 1. (Example 3) 50 g of boron nitride powder was treated with 200 g of a 1% methanol solution of carbon functional silane KBM-503 (γ-methacryloxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical. 5 g of this treated nitrogen boron powder was added to 45 g of trichloroethane.
g, plus 0.1 g of surfactant Emazol L-10.
After adding 2.0 g of KR-230B, the mixture was uniformly dispersed using a homogenizer. This treatment liquid had improved dispersibility and was less likely to settle when compared to the case where untreated boron nitride was used. The film properties after the same coating treatment as in Example 1 were measured. The results are also shown in Table 1. (Effects of the Invention) The boron nitride-containing mold release or lubricant composition of the present invention uses a combination of boron nitride, an organosilicon compound of general formulas (1) to (3), and a surfactant. As a result, boron nitride is uniformly dispersed in the organosilicon compound dissolved in the organic solvent by the action of the surfactant, and the resulting film is dispersed by the action of the functional groups of the organosilicon compound. It has excellent adhesion to the substrate, and since boron nitride is uniformly dispersed in this organosilicon compound, even if boron nitride itself has poor adhesion to the substrate, the coating as a whole has good adhesion to the substrate. It has very high adhesive properties. Moreover,
The above organosilicon compounds have excellent heat resistance and mold release properties, and form a chemically neutral and highly stable film, so boron nitride does not become unevenly distributed in the organosilicon compounds. A film with uniformly dispersed mold release and lubrication effects not only exhibits sufficient mold release and lubrication effects, but also exhibits these mold release and lubrication effects stably over a long period of time, and also has high strength and durability. play.

【table】

Claims (1)

[Claims] 1. 10 to 150 parts by weight of an organosilicon compound and 1 to 10 parts by weight of a surfactant per 100 parts by weight of boron nitride powder.
Parts by weight are dispersed and dissolved in an organic solvent, and the organosilicon compound is one or more selected from the following general formulas (1), (2), and (3). Mold or lubricating compositions. (Here, R ¹ is an atom or group selected from a hydrogen atom or an unsubstituted or substituted monovalent hydrocarbon group, a and b are 0<a<2, 0.001<b<0.5) (Here, R ² and R ³ are hydrogen atoms or atoms or groups selected from the same or different unsubstituted or substituted monovalent hydrocarbon groups, and c and d are 0<c, d<
2, m, n are m≧1, n≧0) R ⁴ _e Si (OR ⁵ ) _4-e …(3) (where R ⁴ is selected from unsubstituted or substituted monovalent hydrocarbon groups group, R ⁵ is a saturated unsubstituted or substituted monovalent hydrocarbon group, e is an integer selected from 1, 2, 3)