JP2783627B2 - Composition for coating - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a composition for forming a good film. The composition can form a film on the surface of various molded articles to form a protective film, or the film can be used as a release agent. In particular, when a film made of the composition is formed on the surface of a gypsum model, and a mold corresponding to the model is formed through the film, the agent functions as an excellent release agent. For example, one typical use is a dental resin release agent. That is, when a coating made of the coating composition of the present invention is formed on a gypsum model surface at the time of making an inlay using a dental composite resin, and an inlay is formed with the composite resin through this coating, it is extremely easy to form the cured inlay of the inlay. It has the advantage that it can be released.

(Problems to be Solved by the Invention) Conventionally, various compositions for forming a film are known. In addition to the use as a simple protective film, the coating is often widely used as a release agent. For example, when curing an inorganic cured product such as a plaster or the like with a metal mold, water, a silicone resin, paraffin wax or the like is used as a release agent, and when molding a dental resin, for example, Sodium alginate aqueous solution, tin foil, as a release agent for gypsum model and composite resin
Cellophane is used. However, these known release agents require a large force to release, the surface of the separated cured product is not smooth, the dimensional accuracy is not good, and the like, which is necessarily satisfactory. Was not. Particularly, a release agent of an aqueous solution of sodium alginate used in the field of dentistry has a drawback that the working efficiency is poor because a long time is required for drying after application.

(Means for Solving the Problems) The present inventors have intensively studied to compensate for such a drawback. As a result, it has been found that a composition in which a specific amount of a sucrose fatty acid ester and a silicone oil are mixed has excellent film-forming properties, high accuracy, and excellent mold releasability, thereby completing the present invention.

That is, the present invention is characterized in that (a) 100 parts by weight of a sucrose fatty acid ester and (b) 10 to 800 parts by weight of a silicone oil having a viscosity of 1 to 2000 cSt (25 ° C.) are dissolved in an organic solvent. It is a composition for a coating.

One of the components constituting the composition of the present invention is a sucrose fatty acid ester. The sucrose fatty acid ester is a known compound, and is an ester compound of sucrose and a fatty acid. The fatty acid is not particularly limited, and known fatty acids can be used alone or in combination. Generally preferred fatty acids are those having 15 to 20 carbon atoms, such as acetic acid, oleic acid, palmitic acid, stearic acid and the like. Specific examples of the most suitably used sucrose fatty acid esters include sucrose acetate, sucrose oleate, sucrose palmitate, and sucrose stearate.

Other essential components constituting the composition of the present invention have a viscosity of 1
It is a silicone oil having a viscosity of 20002000 cSt (25 ° C.). The silicone oil is not particularly limited, and known silicone oils can be used alone or in combination. Examples of the silicone oil generally preferably used include silicone oils such as dimethylpolysiloxane, methylhydrogenpolysiloxane, dihydrogenpolysiloxane, methylphenylpolysiloxane, fluorosilicone, and amino-modified and epoxy-modified silicone.

The silicone oil of the present invention is a sucrose fatty acid ester
10 parts by weight to 800 parts by weight, preferably 20 parts by weight, per 100 parts by weight
It is desirable to use it in the range of parts by weight to 700 parts by weight. If the amount is less than the above lower limit, the film formation is not sufficient, or the release property tends to be low when used as a release agent. On the other hand, if the amount used is larger than the above upper limit, the coating tends to be uneven or the strength of the coating tends to be insufficient.

The coating composition of the present invention is characterized in that the sucrose fatty acid ester
100 parts by weight and 10 to 800 parts by weight of the silicone oil are dissolved in an organic solvent. A coating can be formed by applying the composition to an object to be treated and then removing the organic solvent by evaporation.

As the organic solvent, a volatile organic solvent is generally suitably used, and a known solvent that dissolves both the sucrose fatty acid ester and the silicone oil is not particularly limited, alone or
Used in combination. Particularly preferably used organic solvents are halogen-based organic solvents and alcohol-based organic solvents. The halogenated organic solvent is, for example, a halogenated lower hydrocarbon such as methylene chloride, chloroform, carbon tetrachloride, ethylene chloride, methyl chloroform, and chlorofluorocarbon,
Alcohol organic solvents are methanol, ethanol,
Lower alcohols such as propyl alcohol, isopropyl alcohol, 1-butanol, 2-butanol and isobutyl alcohol are preferably used.

The amount of the volatile organic solvent used may be determined as necessary, but is usually 200 parts by weight to 1000 parts by weight, preferably 300 parts by weight, based on 100 parts by weight of the total amount of the sucrose fatty acid ester and the silicone oil. It is preferable to select from the range of from 900 parts by weight to 900 parts by weight.

When the coating composition of the present invention is stored or used at a relatively low temperature (20 ° C. or lower), a mixed solvent of a halogen-based organic solvent and an alcohol-based organic solvent is suitably employed. When dissolved in a single solvent, sucrose fatty acid ester, which is one of the components, tends to precipitate at a temperature of 20 ° C or lower, and in the winter, etc., it is necessary to heat each time it is used. The sucrose fatty acid ester does not precipitate even at the comparatively low temperature. Even if it is precipitated, it can be dissolved in a short time by returning it to around 20 ° C. Specific examples of the solvent used in combination include methylene chloride and chloroform as halogen-based organic solvents; and methanol and ethanol as alcohol-based organic solvents. In particular, methylene chloride-ethanol is preferred from the viewpoint of toxicity to the human body. preferable. The mixing ratio of these two solvents is 5 to 70 parts by weight, especially 5 to 40 parts by weight of the alcoholic organic solvent with respect to 100 parts by weight of the halogenated organic solvent, so that precipitation of the sucrose fatty acid ester at low temperatures is prevented. It is preferable because the effect of the

It is often a preferable embodiment to appropriately add a known resin or inorganic filler to the coating composition of the present invention, if necessary, in order to improve the mold release ability and adjust the viscosity. The resin inorganic filler is not particularly limited and can be appropriately selected and used. Specific examples of commonly used resins include, as the resin, polymethyl methacrylate, polystyrene, polyvinyl alcohol, polyethylene glycol,
Polyvinyl butyral, hydroxypropyl cellulose polyvinyl pyrrolidone, and the like. As the inorganic filler, for example, quartz, amorphous silica, silica zirconia,
Clay, aluminum oxide, talc, mica, kaolin,
Glass, barium sulfate, titanium oxide, silicon nitride, aluminum nitride, calcium carbonate, and the like.

The amount of the resin and the inorganic filler to be added may be appropriately determined so as not to adversely affect the viscosity and the releasing ability, but is generally 50 parts by weight or less based on 100 parts by weight of the sucrose fatty acid ester. Is preferred.

(Effects of the Invention) As described above, the coating composition of the present invention can be applied to a molded article or a form to be protected and an organic solvent can be removed to form a uniform and strong coating. Therefore, it can be used not only for various protective coatings but also as a release agent. In particular, it has good releasability from an inorganic cured product such as gypsum, and is effective as a release agent for an inorganic cured product. This effect is achieved only by using both essential components of sucrose fatty acid ester and silicone oil together, and is not exhibited even if each component is used alone. That is, when sucrose fatty acid ester alone is used, it has a film forming ability but insufficient releasability, and when silicone oil alone is used, it has no film forming ability and is porous such as an inorganic cured product such as gypsum. , Penetrates into the interior and does not exhibit releasability.

〔Example〕

EXAMPLES Hereinafter, in order to more specifically describe the present invention, examples and comparative examples will be described. However, the present invention is not limited to these examples.

Examples 1-11 Using gypsum (ultra-hard plaster manufactured by Jiji Dental Industry Co., Ltd.),
After kneading in a constant temperature chamber at 23 ° C. and 50% humidity, the mixture was poured on a polypropylene film to obtain a flat cured product. On the hardened gypsum surface, the sucrose fatty acid ester and silicone oil shown in Table 1 were dissolved in the solvent shown in Table 1, applied three times using a small brush, and dried by blowing air.

Next, a 1.5 mm thick paraffin wax plate with a 4 mm inner diameter hole was pressed against the gypsum surface, and the hole was filled with a composite resin (Pulphite Light, manufactured by Tokuyama Soda Co., Ltd.). Irradiator (product name: White Light)
Irradiation for 30 seconds gave a cured resin. The releasability of the film formed on the gypsum surface was evaluated by applying a force in a direction parallel to the gypsum surface and measuring a force (shear force) required to peel off the composite resin. The results were as shown in Table 1.

The quick-drying property was evaluated by measuring the time until the tackiness of the coating surface disappeared after the release agent was applied to the gypsum surface three times with a small brush. The results are shown in Table 1.

Examples 12 to 24 After the sucrose fatty acid ester and the silicone oil were dissolved in the mixed organic solvent shown in Table 2, the sucrose fatty acid ester was precipitated at a temperature at which the sucrose fatty acid ester was precipitated. Was measured.

Separability and quick drying of each composition were evaluated in the same manner as in Examples 1 to 11, and the results are shown in Table 2.

Examples 25 to 32 As compositions for coating, the compositions shown in Examples 12 to 19 were used, and sucrose fatty acid esters were once precipitated in a water bath at 0 ° C, and then transferred to a constant temperature room at 23 ° C to dissolve the precipitates. The time to do was measured. The results are shown in Table 3.

From Examples 12 to 24, and 25 to 32, not only that the composition of the present invention is excellent in releasability, but also when a mixed solution combining a halogenated organic solvent and an alcoholic organic solvent is used. It can be seen that the solubility of sucrose fatty acid ester at low temperature is improved.

Comparative Examples 1 to 8 Instead of the components of the coating composition in Example 1,
The procedure was performed in the same manner as in Example 1 except that the components for coating shown in the table were used. The results were as shown in Table 2.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) C09D 183/04 C08L 83/04 C08K 5/15

Claims (1)

(57) [Claims] 1. A coating film comprising: a) 100 parts by weight of a sucrose fatty acid ester and b) 10 to 800 parts by weight of a silicone oil having a viscosity of 1 to 2000 cSt (25 ° C.) in an organic solvent. Composition.