JPH03286927A - Wall material for cooking-utensil - Google Patents

Abstract

PURPOSE:To obtain the title material inside a cooking utensil with both a purifying property and a surface hardness, by a method wherein a porous metal with high strength is formed on a porous member which comprises ceramic fiber as the major constituent and has a high void-rate, and a mold-releasing property by tar is also given on the surface of the porous metal. CONSTITUTION:For the title material, both a ceramic fiber-made porous member 1 and a metallic fiber-made porous member 3 of which the surface is coated are formed in two layers, and are used for walls inside a cooking utensil. The ceramic fiber-made porous member contains oxidic particles comprising at least one of manganese, iron, cobalt, nickel, copper, lanthanum and cerium, in a ceramic fiber comprising at least one of SiO2, Al2O3 and ZrO2 as the major constituent. For the metallic fiber-made porous member, polyborosiloxane or polyborotitanocarboxylane or the mixture thereof is used as a binder, and a compound with layer structure is coated with complex oxide of nickel and molybdenum, and with a material with a heat-resisting property containing an enamel constituent and glass powder, if necessary, an is made in a film. When the title material is used for the walls inside the cooking utensil, oil dirt generated in cooking and stuck on the walls can be purified at the level of 300 deg.C and several minutes.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a wall surface material for a cooking device that is suitable for the internal wall surface of a cooking device and has the ability to oxidize and decompose organic substances such as fats and oils generated from cooked food.

BACKGROUND OF THE INVENTION Cooking appliances that use wall materials that have the function of decomposing and removing dirt that adheres to the internal walls of the cooking appliance under heating when cooking fish, meat, etc. can be broadly classified into the following three types.

The first method is to form an enamel coating on the inner wall of the chamber, raise the temperature inside the chamber so that the surface temperature of the enamel is approximately 450° C. or higher, and use heat to decompose dirt on the surface of the enamel.

The second type uses inorganic metal phosphates, silicates, or enamel as a binder, and contains manganese, iron, cobalt,
This is a case in which a porous film in which transition metal oxides such as copper, copper, etc. or alkaline earth metal oxides are dispersed as a catalyst is formed on the inner wall surface of the refrigerator. Such a film burns and decomposes oil stains at low temperatures using the catalytic action of metal oxides.

The third method uses the same inorganic metal phosphate, silicate, or enamel as a binder, disperses metal oxide powder or noble metal powder, and forms a coating material into a porous metal body to form a surface shape of the porous metal body. This is a case where a catalyst body is formed on the inner wall surface of the refrigerator by coating it so thinly that it remains.

Problems to be Solved by the Invention However, the above conventional techniques have the following problems. Burning off the enamel coating by heat requires a large amount of thermal energy and an insulating structure.

Furthermore, the enamel coating cracks and peels off when the temperature exceeds 500''C.As a result, the iron base material corrodes and becomes unusable as a cooking appliance.

In addition, for porous membranes using phosphates or silicate as a binder, the contact area between the oil and catalyst is increased to ensure complete combustion of oil stains, and the coating is made as porous as possible to improve oxygen dissolution in the coating. Purification performance cannot be obtained unless this is done. However, if it is made porous, the hardness will decrease and it may peel off or
This poses a practical problem as it may cause damage.

Also, when paint is applied to a porous metal body, the oxide or precious metal powder is covered with the binder, reducing its activity.In order to completely burn off the oil stains, a porous metal body with as high a porosity as possible is used to increase oxygen diffusion. There must be,
On the other hand, if the voids are high, problems such as clogging and appearance impractical as interior walls of the refrigerator arise.

Furthermore, metals generally have poor wettability with oil, and oil passes through the metal porous body before being catalytically burned off and accumulates as tar on the back side.

The present invention solves the above-mentioned conventional problems by providing a high-strength metal porous body on a high-porosity porous body mainly composed of ceramic fibers, and further improving tar releasability on the surface of the metal porous body. The purpose of this invention is to provide a refrigerator interior wall material that has both purification performance and surface hardness.

Means for Solving the Problems In order to solve the above problems, in the present invention, catalyst powder and ceramic SaW are compressed! A first porous body formed by lil molding and a second porous body whose surface has purification performance, tar components, and mold release properties are stacked and used for the inner wall of a cooking appliance. This cleans the oil stains that are scattered from the food during cooking and adheres to the internal walls of the refrigerator.

Effect The present invention has the above-mentioned structure, which has the advantage that the porosity is very high and can fully demonstrate the oxidation activity of the catalyst, but has the disadvantage that the surface hardness is low and it is not suitable for practical use alone. The second porous body has extremely high strength and surface hardness, and is coated with a heat-resistant coating to provide excellent mold releasability from tar acid. It is something that can eliminate physical weaknesses.

Example An embodiment of the present invention will be described below.

First, we will explain the manufacturing method of the first porous body (hereinafter referred to as ceramic fiber porous body).
, Mn are mixed in a predetermined molar ratio and made into an aqueous solution, and an aqueous alkaline solution such as NaOH or NazCOs is added to precipitate Ce, Cu, and Mn in the form of hydrates. Next, this precipitate is washed with water until it becomes neutral, dried and then burned at 450° C. or higher, and the resulting oxide is ground with a pestle to form a fine powder.

Silica/alumina fiber (1:1
) with an average fiber diameter of 2.8 μm.

Press ceramic fiber! CeCu at the same time when forming 1t2 type
A ceramic fiber porous body with a porosity of 92% and a thickness of 1 mm was created by dispersing and molding fine powder of 1M4 particles (0<1<1).

Next, the second porous body (hereinafter referred to as metal fiber porous body) and the heat-resistant coating will be explained.The metal fiber porous body is made by laminating fine fibers of austenitic stainless steel and has a thickness of 0.5 mm.
m (porosity 65-80%) and AI nonwoven fabric
A porous material made by sintering fine powder of stainless steel may be used instead of a 1 m thick material (porosity 50 to 60%) sandwiched with expanded metal.

Next, regarding the heat-resistant coating, for example, the binder is polyborosiloxane, the filler is hollow frit and quartz glass, the layered compound is Ho5t, the catalyst is a composite oxide of Ni and Mo, and the solvent is toluene, and the mixture is mixed for 24 hours. The above was dispersed with an attritor and turned into paint.

Spray the paint with a spray gun (DeVilbiss spray gun, nozzle diameter 1.4 φ, air pressure 2-2.5 kg/d)
) was applied onto the metal fiber porous body described above at 100″C → 5
The bottom of the hole was prepared in order from 00"C to 600°C to form a coating.

For composite oxides of Ni and Mo, Ni is nitrate, M
For O, ammonium salt was used as a starting material, and the aqueous solutions of each were mixed, the resulting precipitate was filtered, washed with water, dried, and burned at 450° C. The bottom of the pit was used. The analysis result of the product is NiO:Mo0
s=35:65.

In the present invention, two layers of the ceramic fiber porous body produced as described above and the metal fiber porous body whose surface is coated are used for the inner wall of a cooking appliance.

FIG. 1 shows a conceptual cross-sectional view of the internal wall material.

1 is a ceramic fiber porous body, 2 is an oxide particle (hereinafter referred to as oxide powder), 3 is a metal fiber porous body, 4 is an expanded metal, and 5 is a heat-resistant coating.

Note that the same heat-resistant liquid 1195 as the heat-resistant liquid Wi5 is also applied to each of the metal fiber porous bodies 3.

FIG. 2 is a plan view of the inner wall material surface when used in a cooking appliance. Each side of the cooking chamber has the appearance shown in FIG. 2, and includes a surface 6 of the inner wall material and a supporting frame 7, which is spot welded to the inner wall of the cooking chamber.

FIG. 3 is an external view of a cooking appliance with internal wall material, and the cooking chamber door and other details are omitted.

Next, the oil purification performance of the interior wall surface material of the present invention will be explained.

Fine powder of oxide (however,
Ce:Cu:Mn=1:0.3:0.7 (45
5.10.25.50% by weight of 0'C baked 7i) dispersed in (respectively ■■0(II)) - A laminate of stainless steel fine fibers coated with the heat-resistant coating described above. (■) An AI nonwoven fabric sandwiched with AIII spun metal and the same heat-resistant coating as described above ([F]), and O and [F], and ■ and [F] with O below. The evaluation was made using a stack of sheets.

The evaluation method was to drop 0.15 g of salad oil onto a 0.01 rrr test piece and place it in an oven maintained at a desired temperature. If the salad oil was burnt out, it was evaluated as ○, and if it was not, it was evaluated as x. The results are shown on the skin surface.

(Left below) From Table C1■, in the catalyst used in the present invention, if the oxide is dispersed at 25% by weight or more based on the weight of the ceramic fiber,
It can be seen that salad oil can be burnt out at 00'C.

Judging comprehensively, the ceramic fiber porous body l is 300 C.
You can burn off oil stains with just one.

However, [F] and [F] metal fiber porous bodies 3 alone have poor wettability with oil, and their activity is reduced because they are coated with a coating that emphasizes hardness and deposit releasability rather than catalytic activity. However, the tar remaining on the surface could be easily peeled off by touching it with your hands or cloth. Therefore, if two layers are stacked (0(9>), the oil that has passed through the porous metal fiber body 3 will be decomposed within the porous ceramic fiber body 1, and the small amount of oil that has adhered to the porous metal fiber body 3 will also be absorbed by the lower layer. The oil can be completely burned off with the help of the heat generated when the oil decomposes within the ceramic fiber porous body 1.

Next, the surface hardness and mold releasability, which are other characteristics of the inner wall surface material of the present invention, will be explained.

0.15g of each of the six seasonings: vinegar, soybean oil, ketchup, sauce, and curry powder were added dropwise to the same sample (0■) used for the above-mentioned evaluation of the grilling performance of salad oil, and heated to 380°C. It was heated for 1 hour. As a result, the vinegar, soy sauce, and sauce were burnt without a trace, the Kecak Nobu had hard black ash, the mayonnaise had white ash, and the curry powder had black ash on its surface. However, the ash came off cleanly when touched with hand or cloth, just as in the case of the tar acid component mentioned above. Since the metal fiber porous body 3 with high strength is located on the upper surface, the surface strength seems to pose no practical problem.

In addition, the semi-organic polyborosoloxane and polyborotitanocarbosilane used as the binder of the heat-resistant coating 5 in the present invention are almost completely destroyed when fired at 450°C or higher.
and forms a very dense thin film. Furthermore, by incorporating a layered compound, we improved the releasability between the film surface and the tar acid content, and focused on oxidatively decomposing oil stains on the surface layer of the film, and used a composite oxide of Ni and Mo as a catalyst. Selected and mixed.

Finally, with the present invention, Sera Chinku m! I Regarding the catalyst dispersed in the porous body 1, the above-mentioned Mn, FeCo,
Since at least one oxide of Ni+Cu+La+Ce exhibits high activity against oxidative decomposition of hydrocarbons such as oil stains, the composition is not particularly limited.

As described in detail, the wall material for cooking appliances of the present invention is porous and has a very high ability to decompose oil stains, and when used on the inner walls of cooking appliances, it can remove oil stains that occur during cooking and adhere to the walls. 30
It can be purified at a level of 0"C for several minutes.

In addition, the second porous body, that is, the gold-N fiber porous body and the heat-resistant coating, improves surface hardness and releasability of deposits, so it has a good appearance and feel, and it is easy to remove residual ash and deposits. Since it can be wiped clean, the inner wall surface of the cooker can be kept clean forever.

[Brief explanation of the drawing]

FIG. 1 is a conceptual sectional view of a wall material for a cooker according to an embodiment of the present invention, FIG. 2 is a plan view of the surface of the same material, and FIG. 3 is an external perspective view of a cooker using the same material. 1... Ceramic fiber porous body, 2...
Oxide powder, 3... Metal fiber porous body, 4...
...Exband metal, 5...Heat-resistant coating.

Claims (2)

[Claims] (1) A first ceramic fiber containing oxide particles of at least one of manganese, iron, cobalt, nickel, copper, lanthanum, and cerium in a ceramic fiber containing at least one of SiO_2, Al_2O_3, and ZrO_2 as a main component. A porous body, polyborosiloxane, polyborotitanocarbosilane, or a mixture of the above two types are used as a binder, and a compound having a layered structure is combined with a composite oxide of nickel and molybdenum, and if necessary, an enamel component or glass. A wall material for a cooker, which is made by laminating a second porous body coated with a heat-resistant coating containing powder. (2) The wall surface material for a cooker according to claim (1), wherein the second porous body is made of laminated aluminum or stainless steel fibers and sandwiched with aluminum or stainless expanded metal.