JPH02251430A - Metal parts for gas heater, preparation thereof and gas heater - Google Patents

Abstract

PURPOSE:To enhance heat resistance, corrosion resistance, antistaining properties and scratch resistance and to impart an excellent fine view by forming a ceramics layer to the metal part constituting a gas heater by a sol-gel method. CONSTITUTION:A ceramic layer is formed on the constitutional material of the metal part for a gas heater by a sol-gel method. The ceramics layer due to the sol-gel method can be usually formed by applying the liquid composition of raw materials for forming the ceramics layer to polymerize and gel the same. The liquid composition contains various metal alkoxides or metal hydroxides as the raw materials for forming the ceramics layer. The concn. of the raw materials for forming the ceramics layer in the liquid composition is usually set to about 10-100wt.% and appropriately determined corresponding to the properties of the raw materials to be used. Further, a colloidal substance and/or an inorg. fine powder can be added to the liquid composition of the raw materials for forming the ceramics layer if necessary. By the addition of the colloidal substance and/or the inorg. powder, the ceramics layer formed by the sol-gel method is made more dense.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a metal part for a gas stove, a method for manufacturing a metal part for a gas stove, and a gas stove.

BACKGROUND OF THE INVENTION Conventional techniques and their problems Conventionally, organic resin-coated steel plates, stainless steel plates, enamel plates, and the like have been used as materials for the exterior of gas stoves, which are gas cooking appliances for kitchens.

However, when using organic resin-coated steel sheets, there is a problem that the organic resin coating deteriorates and discolors due to heat, and when using stainless steel sheets, there is a problem that it is difficult to remove oil stains if they adhere. . In addition, since the enamel plate is heavy, the gas stove itself becomes heavy.
Moreover, it has the disadvantage that the film is easily chipped.

Conventionally, the burner part of gas stoves has been made of cast iron, stainless steel, die-cast aluminum, copper alloy, etc. However, these materials tend to deteriorate in appearance due to discoloration and rusting due to heat, and are susceptible to corrosion. There is a problem in that defective parts are likely to occur.

In addition, enamel or stainless steel plates have been conventionally used to catch boiled spills, but they have the disadvantage that if boiling liquid or the like gets on them, it is difficult to remove and it takes time and effort to clean.

Means for Solving the Problems In view of the above-mentioned problems, the inventors of the present invention have improved the heat resistance, corrosion resistance, stain resistance, scratch resistance, etc. of the various metal parts that constitute the gas stove. We have carried out extensive research to give it an excellent sense of beauty. As a result, the inventors discovered that the desired objective could be achieved by forming a ceramic layer on the metal parts constituting the gas stove by the sol-gel method, and thus completed the present invention.

That is, the present invention provides a metal component for a gas stove, a method for manufacturing the metal component, and a gas stove as shown below.

■ Metal parts for gas stoves that have a ceramic layer formed by the sol-gel method.

■ A method for manufacturing metal parts for gas stoves, which comprises applying a liquid composition of raw materials for forming ceramics onto the metal parts constituting the gas stove, and polymerizing and gelling the composition to form a ceramic layer.

■ A gas stove whose components are metal parts with a ceramic layer formed by the sol-gel method.

The materials on which the ceramic layer is formed according to the present invention are various metal parts that constitute a gas stove, such as an exterior cover, a gas burner, a burner head, a saucer,
I can give examples such as ``Gotoku''. The materials of these parts are not particularly limited, and include various metals such as iron, aluminum, copper, stainless steel, and alloys thereof, as well as galvanized,
Materials plated with nickel plating, chrome plating, aluminum plating, or various other metals can also be used.

The metal parts for gas stoves of the present invention can be obtained by forming a ceramic layer by a sol-gel method on various gas stove constituent materials as described above.

Various methods are known for forming ceramic layers using the sol-gel method, and various raw materials are also known, but in the present invention, these are not particularly limited, and any of them may be adopted. can.

Ceramics produced by the sol-gel method can usually be formed by applying a liquid composition of ceramic-forming raw materials and polymerizing and gelling the composition. The liquid composition contains various metal alkoxides and metal hydroxides as raw materials for forming ceramics, and as a preferable example of such raw materials for forming ceramics, 0 formula (R1) mMl (OR2) n (formula Among them, R1 is an alkyl group or vinyl group having 1 to 3 carbon atoms, R2 is hydrogen,
Methyl, ethyl, isopropyl or t-butyl, M is Ca or Ba.

m is 0 or 1, n is 1 or 2), 0 formula (R3) kM2(OR4)ρ (wherein R3 is an alkyl group or vinyl group having 1 to 3 carbon atoms, R4 is hydrogen , methyl, ethyl, isopropyl or t-
Butyl, M2 is A, l;), Y or La5k is 0 or 1
, ρ represents 2 or 3), a compound represented by the formula (Rs ) i M3 (ORB ) j (wherein,
R5 is an alkyl group having 1 to 3 carbon atoms or a vinyl group, R6 is hydrogen, methyl, ethyl, isopropyl or t-butyl,
M3 is Ti, Zr.

Mn5Sn, SL or 5rSi represents 0 or 1, j represents 3 or 4), and the like. These compounds may be used alone or in combination of two or more, and two or more of them may be condensed.

Specific examples of the raw materials for forming ceramics include (a
(OCH3) 2, Ca (OC2Hs) 2, C
a(OC3H7)2. Ca(OCtH9)2-Ba (
OCH3)2, Ba (OC2H5)2, Ba (O
Ca Hy ) 2 , Ba (OCa H9) 2 ,
Aρ(OCH3)3, A,Q(OC2Hs)3,
Ai'(OC3H7)3, AΩ(OCa H9)3, C
H3AΩ(OCH3)2, CH3AΩ(OC2H5)
2, CH3AΩ(OCa Hy )2, CH3AΩ(
OCa H9)2, Ti (OCH3)a, Ti (
OC2H5)4, Ti (OCaHy)A, T
i (OCa H9)4, CH3Ti (OCH3)
3, CH3Ti (OC2H5)3, CH3Ti (O
Ca Hy ) 3 , CH3Ti (OC4H9) 3
, C2H5Ti (OCH3)3, C2H5Ti (O
C2H5)3, C2H5Ti (OCaHy)3
, C2H5Ti (OCa Hg)3, Si (O
CH3)4, Si (OC2H5)A, Si (OC
3H7)4% Si (OC4H9)4, CH3Si
(OCH3)3, CH3Si (OC2H5)3, CH
3SL (OCa Hy )3 , CH3Si (OC
a Hg)3, C2H5Si (OCH3)3, C2H
5St (OC2H5)3, C2H5S i (OCa
Hy ) 3, C2H5Si (OC4Hg)3, Z
r (OCH3)4, Zr (OC2H5) 4, Zr
(OCa Hy) 4, Zr (OCAH9) 4,
CH3Zr (OCH3)3, CH3Zr (OC2H
5) 3, CH3Zr (OCa Hy)3, CH3Zr
(OCa Ho) 3 , C2H5Zr (OCH3
) 3, C2H5Zr (OC2H5) 3, C2H5Z r (OCa Hy) 3, C2H5Z
r (OC4H9)3, Y(OCH3)3, Y (OC
2H5) 3, Y (OCa Hy) 3, Y (
OCa Hg) 3, L a (OCH3) s,
La (OC2Hs) 3, La (OCa Hy
) 3, La (OCa Hg)3, Mn (OC
H3) 4, Mn (OC2H5) 4, Mn (OC
a Hy ) 4, Mn (OCa Hg) 4.3n
(OCH3) A, Sn (OC2Hs) a, Sn
(OCa Hy) 4, Sn (OCa Hg)
a, S r (OCH3) 4, Sr (OC2H
5)4,Sr(OCaHy)4,Sr(OC
4Hg)4, Ca (OH)2, Ba (OH)2, A
,Q(OH)3,CH3AΩ(OH)2,TL
(OH)4, CH3Ti (OH)3, C2H5T
i (OH)3, S i (OH)a, CH3S
i (OH) 3, C2H5S i (OH)3
,Zr(OH)4,CH3Zr(OH)3,C
2H5Zr (OH)3, Y (OH)3, La (
OH)3, Mn (OH)4, Sn (OH) a
, S r (OH) 4 and the like. Moreover, these condensates can be freely produced by any combination of the above-mentioned compounds, and the molecular weight can also be selected as appropriate. Examples of condensates include Zr03i (OC2H5) 6 , A, QO8i (
OC2Hs ) s, TiO3i (OC2H5) s
, (C3Hy 0) 3 Z rO3i (OC2H5)
3, (C4Hg O) 3 Z rO8i (OC2
H5) 3, (C3Hy 0) 3 TiO3i (O
C2Hs) 3, (CmuHg0)3TiO3i (
OC2H5)3, (C3Hy O)2 AρO3i
(OC2H5)3, (Ca H90)2 AΩO8i
(OC2Hs)3, etc. can be shown.

These raw materials for forming ceramics usually contain organic solvents,
It is used after being dissolved or dispersed in water, a mixed solvent thereof, etc., but if the raw material for forming ceramics itself is liquid, it is also possible to use it as it is. As the organic solvent, any one used in the liquid composition of the known sol-gel method can be used, such as lower alcohols such as methanol, ethanol, propatool, butanol, ethylene glycol monoalkyl ether, diethylene glycol monoalkyl ether, etc. , hydrocarbon ether alcohols having methyl, ethyl, propyl, butyl, etc. as an alkyl group such as propylene glycol monoalkyl ether, dipropylene glycol monoalkyl ether, ethylene glycol monoalkyl ether acetate, diethylene glycol monoalkyl ether acetate,
Acetate esters of the above hydrocarbon ether alcohols such as propylene glycol monoalkyl ether acetate and dipropylene glycol monoalkyl ether acetate, acetate esters of alcohols such as ethoxyethyl acetate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate Acetate esters such as, acetone, etc. can be used.

The concentration of the raw material for forming ceramics in the liquid composition is usually about 10 to 100% by weight, and may be determined as appropriate depending on the properties of the raw material used.

In addition, the liquid composition of the raw material for forming ceramics includes:
Colloidal substances and/or inorganic fine powders can be added as necessary. By adding the colloidal substance and/or the inorganic fine powder, the ceramic layer formed by the sol-gel method is made more dense.

The colloidal substance used in the present invention is 10 to 100
It refers to liquid or solid particles of about 0.00 angstroms dispersed in a dispersion medium, and various known types can be used. As the dispersion medium, organic solvents such as the above-mentioned lower alcohols, hydrocarbon ether alcohols, and acetic esters thereof, and water are used alone or in combination, and the concentration of the dispersed particles is 10 to 60% by weight. Generally, it is about 10%. In the present invention, any such colloidal substances can be used. Specific examples of colloidal substances include colloidal silica, colloidal alumina, colloidal titanium oxide, colloidal zirconium oxide, colloidal zirconium silicate, colloidal aluminum hydroxide, and colloidal zirconium hydroxide. .

The inorganic fine powder has a particle size of about 5 to 150 mμ, and for example, alumina fine powder, titanium oxide fine powder, silica fine powder, etc. can be used.

The colloidal substance and/or inorganic fine powder can be added up to about 70% by weight, preferably about 3 to 40% by weight, in the liquid composition of the raw material for forming ceramics.

If necessary, a pigment, a coating reinforcing material, etc. may be added to the liquid composition of the raw material for forming ceramics. As the pigment, ordinary inorganic or organic pigments can be used, such as magnesium oxide, silicon nitride, boron nitride, titanium nitride, nickel oxide, quartz, silica, zirconium silicate, alumina, titanium oxide, and titanium. yellow,
Magnesium carbonate, dolomite, silicon carbide, tungsten carbide, iron oxide (red, black), barium yellow, antimony yellow, cobalt blue, cobalt violet, cobalt green, manganese black, manganese blue, manganese violet, strontium chromate, talc, chromium oxide Hydrate green, chromium oxide green, zinc green, barium carbonate, chalk, precipitated calcium carbonate, aluminum hydrate, zinc oxide, fluorite, molybdenum red, molybdenum orange, chrome yellow, lead chromate, ultramarine, vermilion, basic carbonate Lead, azo pigments, etc. can be used. Pigments can be used together with pigment fillers, thickeners, etc. in accordance with conventional methods.

The coating reinforcing material is an inorganic fibrous material, and typical examples thereof include potassium titanate, silicon carbide, silicon nitride, aluminum oxide, beryllia, boron carbide, silicate glass, and quartz.

The pigment can be added to the liquid composition up to about 70% by weight, and the coating reinforcing material can be added to the liquid composition up to about 70% by weight, preferably about 1 to 65% by weight.

The pH of the liquid composition described above is preferably adjusted to about 2.5 to 6.0 in order to prevent rapid gelation. p
For H adjustment, inorganic or organic acids such as hydrochloric acid, acetic acid, chloroacetic acid, citric acid, maleic acid, oxalic acid, toluenesulfonic acid, glutaric acid, dimethylmalonic acid, and benzoic acid can be used.

The liquid composition further contains carbon dioxide as a buffered latent catalyst that does not cause the liquid composition to gel at room temperature (and that can be dissociated by heating to accelerate the polymerization of the liquid composition). acid metal salts, amine carboxylates,
Quaternary ammonium carboxylate, nitrate, etc. can be added to the liquid composition up to about 1.5% by weight.

Examples of such buffered latent catalysts include dimethylamine acetate, ethanolamine acetate, dimethylaniline formate, sodium acetate, sodium propionate, potassium formate, sodium formate, benzyltrimethylammonium acetate, sodium nitrate, and ammonium nitrate.

Furthermore, when it is desired to impart flexibility to the ceramic film or to enable thick coating, a resin-modified silicone resin can be blended into the liquid composition. By blending silicone resin, the flexibility of the ceramic film is improved, and by using a resin-modified film, good adhesion to plastic materials can be maintained. Examples of types of resin modification include epoxy modification, polyester-alkyd modification, phenol modification, and acrylic modification. As a resin-modified silicone resin,
Any material can be used without limitation as long as it is soluble in the liquid composition of the raw material for forming ceramics. good.

In the present invention, a ceramic layer is formed by applying the above-described liquid composition of raw materials for forming ceramics onto a metal component for a gas stove, which is a base material, and polymerizing and gelling the composition. It is sufficient to provide the ceramic layer only on the required parts depending on the purpose of each metal part.For example, it is sufficient to provide the ceramic layer on the surface of the outer cover, the top surface of the tray, the outside of the burner, etc. By doing so, the intended purpose can be achieved. Burner heads and the like are usually provided with a ceramic layer over the entire surface.

The coating method is not particularly limited, and for example, a spray method, a roll coating method, a dip method, a curtain flow method, a printing method, etc. can be employed. Polymerization and gelation of the liquid composition proceed even at room temperature, but heating shortens the gelation time and increases the polymerization density, making the ceramic layer more dense. The higher the heating temperature, the more dense the ceramic layer can be, but from a cost standpoint, heating at about 100 to 250° C. for about 10 to 30 minutes is appropriate.

In order to completely prevent the formation of pinholes in the ceramic layer, after the liquid composition of the raw material for forming ceramics is applied, dried, or cured by heating, one or two layers of the liquid composition of the raw material for ceramics is further applied. It is preferable to coat two or more layers and cure them to form two or more ceramic layers by the sol-gel method.

In addition, when a pigment is added to the liquid composition of the raw material for forming ceramics, a ceramic layer made of the liquid composition of the raw material for ceramics formation to which no pigment is added is added on the ceramic layer to be formed. 0.5~40
By providing the ceramic layer with a thickness of approximately μm, the surface layer of the ceramic layer can be made dense and the water repellency can be further improved.

The ceramic layer formed by the sol-gel method has a total thickness of 3 to 1
The thickness may be approximately 50 μm.

The gas stove of the present invention can be manufactured by providing a ceramic layer on the necessary metal parts by the method described above before assembling each component, and then assembling each part, or by assembling each part and then applying the necessary It can be obtained by any method of providing a ceramic layer on a component. Furthermore, in the gas stove of the present invention, it is not necessary to provide ceramic layers on all metal parts, and it is sufficient to provide ceramic layers only on necessary metal parts depending on the required characteristics.

The present invention can be applied to various conventional gas stoves, for example, in addition to so-called gas staple stoves, it can be applied to gas stove portions in gas ranges, gas cabinets, gas drop-in stoves, and the like.

Effects of the Invention The metal parts for gas stoves according to the present invention have a dense ceramic layer formed by the sol-gel method, and the ceramic layer is a smooth film with extremely good adhesion and no pinholes. Metal parts having such ceramic layers have excellent heat resistance, can prevent metal oxidation at high temperatures, and have very little discoloration or loss of gloss. Furthermore, it has excellent properties such as being hard to be scratched due to its high surface hardness, and being non-staining, making it easy to remove food stains and maintaining its aesthetic appearance for a long period of time. Furthermore, since it is possible to freely color the liquid composition of the raw material for forming ceramics by appropriately selecting the pigment to be added to the liquid composition, there is also the advantage that products with a variety of colors can be provided.

Example Hereinafter, the present invention will be explained in more detail by showing examples.

Example 1 Ceramic layers were formed on each of the metal components of a gas stove, such as the gas burner cover, the burner head, and the tray, by the following method.

That is, 15 g of isopropyl alcohol, 13 g of finely powdered alumina, 15 g of water, and 30 g of methyltrimethoxysilane.
25 g of titanium oxide 1 15 g of silicone
A liquid composition for forming a ceramic layer was prepared by adding and mixing 9 g of potassium titanate fibers and 0.1 g of hydrochloric acid, and this was applied to each of the above parts by a spray method and heated at 150°C for 20 minutes.
Heated for a minute.

On top of this, the above liquid composition was applied again and heated to 150°C for 20 minutes.
The mixture was heated for a minute to form a white ceramic layer of 30 μm in total by the sol-gel method. Next, 35 g of acidic colloidal silica aqueous solution (concentration 30% by weight), 40 g of isopropyl alcohol, and 25 g of methyltrimethoxysilane.
to prepare a liquid composition for forming a ceramic layer,
Coated on the above white ceramic layer by spraying method,
A transparent ceramic layer having a thickness of 5 μm was provided by heating at 0° C. for 20 minutes.

Performance tests were conducted on each of the obtained parts using the following method. The results are shown in Table 1.

1 Adhesion: JI 5K-5400 Paint film adhesion test 2 Hardness: Empi hardness 3 Scratch resistance: Scratch test with a nylon brush 10,000 brushing times 4 Heat resistance: 400℃ or 600℃ 5 Salt water resistance = Dropwise addition of 2% saline solution, 10 cycles of heating at 400°C 6 Salt water spray properties: J I 5Z2371 salt water spray test 1000 hours 7 Boiling water resistance: Boiling water immersion 160 hours 8 Thermal shock resistance = 100 cycles of 1 hour each from 20°C to 600°C 9 Impact resistance: DuPont impact test 10 Moisture resistance: J I 5K-2246 wet test, 000 hours 11 Stain resistance ■: Stain after heating cooking oil at 250°C
■: Stain caused by vinegar ■: Stain after heating ketchup at 250°C ■: Stain after heating soy sauce at 250°C ■: Stain after heating butter at 250°C ■: Stain after heating sauce at 250°C Example 2 Si ( OC2H5) 4 and Z r (OCA H9)
Partial condensate of A (C4Hg O) 3 Z r-0-
3L (OC2H5) 335g, isopropyl alcohol 12g1 butylcellosolve 3g1, zirconium silicate 20
g1 titanium oxide 12g1 cobalt clean 8g, acetic acid 0
．． 5 g was added and mixed to prepare a liquid composition for forming a ceramic layer, and this was applied to the cast iron gas burner and brass gas burner head of a table gas stove by a spray method, heated at 150°C for 20 minutes, and thickened. 15μm
A light green ceramic layer was provided.

Also, 10g of isopropyl alcohol, 5g of ethyl acetate
, and 13 g of fine powder alumina with a particle size of 20 mμ 1 30 g of methyltrimethoxysilane in a mixed solvent consisting of 15 g of water
20 g of titanium white, 15 g of zirconium silicate, 7 g of cobalt green, 9 g of alumina fiber, and 0.0 g of hydrochloric acid. A liquid composition for forming a ceramic layer is prepared by adding and mixing Ig, and this is applied to the surface of an exterior cover, a tray, etc. by electrostatic spraying, heated at 150°C for 20 minutes, and then applied again. The composition was applied and heated at 150° C. for 20 minutes to form a light green ceramic layer of 30 μm in total by the sol-gel method.

Then, a methanol sol solution of colloidal silica (concentration 4
0% by weight) 30sr, isopropyl alcohol 43g1
A composition obtained by heating and mixing 2 g of water and 25 g of methyltrimethoxysilane at 60°C was applied onto the ceramic coating layer of each of the above parts by electrostatic spraying, and
It was heated at ℃ for 20 minutes to form a 7 μm transparent ceramic film.

Performance tests were conducted on the obtained gas burner and gas burner head in the same manner as in Example 1, and they were found to have the same excellent performance as in Example 1.

Further, when a gas stove using the above-mentioned parts was tested for 6 months of continuous use, no discoloration or abnormality occurred in the coating film. Another 15 minutes 0N10FF 4
No discoloration or abnormality occurred in the coating film even after cycling Tetos 000 times.

As can be seen from the above results, the gas stove of the present invention did not cause discoloration or peeling of the coating due to heat, and was able to maintain its aesthetic appearance for a long period of time.

(that's all)

Claims (3)

[Claims] (1) A metal part for a gas stove having a ceramic layer formed by a sol-gel method. (2) A method for manufacturing metal parts for a gas stove, which comprises applying a liquid composition of a raw material for forming ceramics onto the metal parts constituting the gas stove, and polymerizing and gelling the composition to form a ceramic layer. . (3) A gas stove whose components include metal parts having a ceramic layer formed by a sol-gel method.