JPH04102418A - Cooking hood - Google Patents

Abstract

PURPOSE:To form a high-hardness coating film while keeping an excellent heat-resistance by coating and baking a heat-resistant paint consisting of polymetallocarbosilane, silicone resin, inorganic filler, alkylalkoxysilane and alkoxide of metal, on the outside of a hood. CONSTITUTION:Polymetallocarbosilane is itself a recognized organic silicon polymer. As an embodiment of silicone resin, denaturated silicone that has been reacted with a denaturation resin such as dimethylpolysiloxane is given. As inorganic fillers, at least one kind out of oxide, boride, phosphate, silicate, silicide, nitride, and carbide is used. As alkylalkoxysilane, methyltrimethoxysilane or the like can be given. As alkoxide of metal being selected from titanium, zirconium, and aluminum, tetraethoxytitanium or the like can be given. As to the method for coating and baking these heat-resistant paints on a cooking hood, there is no special restriction.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a cooking hood that is placed on a cooking plate to cover food such as hamburgers or steaks when cooking the food.

(Prior art and its problems) Utility Model Application Publication No. 2-4526 discloses a cooking hood coated with a heat-resistant paint in which polymetallocarbosilane, silicone resin, and inorganic filler are dispersed or dissolved in an organic solvent. is disclosed.

Compared to unpainted cooking hoods, the cooking hood described in this publication maintains its visual beauty without darkening the surface during use, and also has a strong bond between the coating film and the base metal. 2 because of its high adhesion! It has the excellent feature that the film does not peel off from the base metal.

On the other hand, the coating film in the cooking hood described in the above publication is
The general baking temperature for heat-resistant paint is 250~4
It is formed by curing polymetallocarbosilane by heating to 50°C, and the pencil hardness of the coating is 2H.
-3H, has a relatively low hardness, and has the problem of easily scratching the coating film.

Therefore, when using or cleaning the cooking hood, it is necessary to handle it carefully so as not to damage the coating.

(Technical means for explaining the problem) The present invention provides a cooking hood in which a coating film with high hardness is formed while maintaining the excellent heat resistance of a polymetallocarbosilane coating.

According to the present invention, in a metal cooking hood that covers a cooking plate on which food is placed, the outer surface of the hood contains polymetallocarbosilane, silicone resin, inorganic filler, alkyl alkoxysilane, and titanium and zirconium. A cooking hood is provided which is coated with a heat-resistant paint made of a metal alkoxide selected from aluminum and aluminum.

The polymetallocarbosilane used in the present invention is an organosilicon polymer known per se, for example, Japanese Patent Publication No. 61-4
No. 9335, No. 62-60414, No. 63-
It can be prepared according to the methods described in JP-A No. 37139 and JP-A No. 63-49691. The descriptions in these publications are incorporated herein by reference.

A typical method for producing polymetallocarbosilane is a method in which a polycarbosilane having a number average molecular weight of 200 to 1,000 is reacted with a titanium or zirconium alkoxide. Through this reaction, polycarbosilane is a crosslinked polymer with a number average molecular weight of 700 to 100°000, in which some of the silicon atoms in its skeleton are bonded via oxygen atoms with titanium atoms or zirconium atoms. A metallocarbosilane is obtained.

An organic solvent solution of the above polymetallocarbosilane is commercially available from Ube Industries Aji as Tyrannocoat [F] varnish type.

Specific examples of the silicone resin in the present invention include dimethylpolysiloxane, methylphenylpolysiloxane,
Pure silicone resins such as diphenylpolysiloxane, pure silicone resins, alkyd resins, polyester resins,
Examples include modified silicones reacted with modifying resins such as acrylic resins and epoxy resins.

The blending ratio of the silicone resin is 10 to 900 parts by weight, particularly 50 to 900 parts by weight, per 100 parts by weight of polymetallocarbosilane.
Preferably, it is 500 parts by weight. If the blending ratio of silicone resin is too small, the flexibility of the coating film will be reduced due to baking, and if the ratio is too high, the heat resistance and corrosion resistance of the coating film will be reduced due to baking.

As the inorganic filler in the present invention, at least one selected from oxides, borides, phosphates, silicates, silicides, borides, nitrides, and carbides is used. Examples include magnesium, calcium, barium,
Titanium, zirconium, chromium, manganese, iron, cobalt, nickel, copper, zinc, boron, aluminum, silicon oxides, carbides, nitrides, silicides, borides, lithium, sodium, potassium, magnesium, calcium or zinc. Examples include borates, phosphates, and silicates.

The blending ratio of the inorganic filler is polymetallocarbosilane 10
0 parts by weight, 10 to 900 parts by weight, especially 50 to 50 parts by weight
Preferably, it is 0 parts by weight. By incorporating an inorganic filler, the adhesion of the coating film to the substrate during baking is improved, but if the proportion of the inorganic filler is too high, the flexibility of the coating film decreases.

The alkylalkoxysilane in the present invention has the formula R' y+ 31 (OR") a-n (wherein, R
1 and R2 each represent an alkyl group, n represents 1-3. ) are generally used. Specific examples thereof include methyltrimethoxysilane, ethyltrimethoxysilane, butyltriethoxysilane, methyltripropoxysilane, dimethyljethoxysilane, diethyldibutoxysilane, triethylethoxysilane, and trimethylbutoxysilane.

The blending ratio of alkyl alkoxysilane is 0.2 to 10 mol, especially 0.2 to 10 mol per 100 g of polymetallocarbosilane.
．． The amount is preferably 5 to 5 mol. If the blending ratio of alkyl alkoxysilane is too small, the hardness of the painted film will not be sufficient, and if the blending ratio is too large, the initial adhesion of the painted film to the substrate will decrease.

The metal alkoxide selected from titanium, zirconium and aluminum in the present invention has the formula R", M (OR'> 4-m (wherein R3 and R4 each represent an alkyl group, and M is titanium or represents zirconium, m is 1 to 3), or a compound represented by the formula R', Al1 (OR'') 3
-p (wherein R″ and Rh each represent an alkyl group, and p is 1 to 2) is used. Specific examples thereof include tetraethoxytitanium, tetrabutoxytitanium, Titanium, tetramethoxyzirconium, tetrapropoxyzirconium, tetrabutoxyzirconium, methyltributoxytitanium, dimethyljethoxytitanium, ethyltriptoxyzirconium, dimethyldibutoxyzirconium, trimethyltriethoxytitanium, triethoxyaluminum, tributoxyaluminum, tripropoxyaluminum can be mentioned.

The mixing ratio of the above metal alkoxide is 0.1 to 5 mol, particularly 0.2 mol, per 100 g of polymetallocarbosilane.
The amount is preferably 5 to 2 moles. If the blending ratio of metal alkoxide is too small, the hardness of the painted film will not be sufficient, and if the blending ratio is too high, the stability as a paint will be impaired and it will gel during short-term storage.

The above coating components in the present invention are used after being dispersed or dissolved in an organic solvent. Any organic solvent can be used as long as it is capable of dissolving polymetallocarbosilane and silicone resin. Specific examples include toluene, xylene, n-butanol, isobutanol, butyl acetate, mineral spirit, solvent naphtha, ethyl cellosolve, and cellosolve acetate.

The proportion of the organic solvent to be used varies depending on the type and blending proportion of the film-forming components, and can be appropriately determined by those skilled in the art in accordance with the disclosure of the present invention.

The cooking hood to which the heat-resistant paint is baked is designed to cover food when it is cooked on a cooking board such as an iron plate or metal net.

An example of this is the Chimney Roaster manufactured by Chimney ■.

There are no particular restrictions on the method of applying the heat-resistant paint of the present invention to the cooking method hood, and the coating is applied by a known method such as brushing, roll coating, spraying, dipping, etc., followed by drying and baking. .

The coating amount of the heat-resistant paint is preferably 20 to 100 g/n (20 to 100 g/n). If the coating amount is too small, pinholes are likely to occur in the coating film and corrosion resistance will be reduced.

On the other hand, if the coating amount is excessively large, cracks are likely to occur in the coating film when the coating film is exposed to high temperatures or to cooling/heating cycles.

The baking temperature is preferably 150°C or higher, particularly 200°C or higher. If the baking temperature is too low, the polymetallocarbosilane, which is one of the paint components, will not be sufficiently cured, resulting in a decrease in the strength of the coating film and also in its impact resistance.

(Example) Examples and comparative examples are shown below. Unless otherwise specified in the examples, "%" and "parts" refer to "% by weight" and "parts by weight," respectively.

The pencil hardness of the formed coating film was measured according to JIS K 5400.

Further, the heat resistance of the coating film was evaluated as follows.

That is, after holding the object to be coated in an air open environment at 1000°C for 200 hours, it is taken out from the oven and slowly cooled in the air. Then, a cross cut of 11 pitches is made in the coating film using a cutter knife, and this area is covered with adhesive cellophane. A tape was applied, and after the tape was rapidly removed, the presence or absence of peeling of the paint film was examined. The heat resistance was rated as "good" if no peeling of the coating film was observed, and the heat resistance was rated as "poor" if any peeling was observed.

Example 1 100 parts of a 50% xylene solution of polytitanocarbosilane (manufactured by Ube Industries, Ltd., Tyrannocoat 0 Fes Type), 100 parts of a 50% xylene solution of methylphenylpolysiloxane (manufactured by Toshiba Silicone Corporation, TSR-116), silicon carbide 100 parts of powder, 150 parts of methyltrimethoxysilane,
A heat-resistant paint was prepared by mixing 250 parts of tetrabutoxytitanium and 70 parts of xylene using a mixer.

Separately, a stainless steel plate (SLIS 316L) with a thickness of 0.6 mm was degreased with acetone and air-dried as a base material.

Approximately 30μ of the heat-resistant paint is applied to the base material using a spray gun.
It was coated to a very thick coating, baked in an air oven at 300"C for 25 minutes, and then slowly cooled.

The pencil hardness of the formed coating film was 9H or higher.

Furthermore, the heat resistance of this coating film was "good."

Example 2 Example 1 was repeated, except that 400 parts of tetrabutoxyzirconium was used instead of tetrabutoxytitanium.

The pencil hardness of the resulting coating film is 9H or higher, and the heat resistance is "
It was "Good".

Comparative Example 1 Example 1 except that tetrabutoxytitanium was not blended
repeated.

The pencil hardness of the resulting coating film was 2H, and the heat resistance was "good".
Met.

Example 3 Example 1 was repeated except that 200 parts of silicon nitride powder was used instead of silicon carbide powder.

The pencil hardness of the resulting coating film is 9H or higher, and the heat resistance is "
It was "Good".

Example 4 Example 1 was repeated except that 50 parts of zirconium oxide powder was used instead of silicon carbide powder.

The pencil hardness of the resulting coating film is 9H or higher, and the heat resistance is "
It was a good J.

Example 5 The heat-resistant paint prepared in Example 1 was applied to the outer surface of a chimney roaster made by Chimney ■ to a thickness of approximately 30 μm, and after baking at 300°C for 25 minutes in an air oven. It was slowly cooled.

The surface of the obtained cooking hood did not darken during use and was resistant to scratches.

Claims (1)

[Claims] A metal cooking hood that covers the cooking plate on which the food is placed, the outer surface of the hood containing a polymetallocarbosilane, a silicone resin, an inorganic filler, an alkyl alkoxysilane, and a material selected from titanium, zirconium, and aluminium. A cooking hood coated with a heat-resistant paint made of metal alkoxide.