JPH04244518A - Heating cooking device - Google Patents

Abstract

PURPOSE:To prevent any contamination produced upon cooking from adhering to a device and remove any adhering contamination with ease by employing as an inner casing one yielded by chemically bonding a silane surface active agent having a carbon fluoride group to a metal surface as a monomolecular film. CONSTITUTION:There is employed a nonaqueous solvent in which a substance including a carbon fluoride group and a silane group is mixed to prepare n-hexadecane carbon tetrachloride, and chloroform solutions. When an iron plate 12 degreased by trichloroethylene is dipped in said solutions, a dehydrochlorination reaction is produced with the aid of a hydroxide group and a chlorosilyl group of a substance including the carbon fluoride group and the silane group because an oxide film surface of the iron plate includes the hydroxyl group, and hereby monomolecules of a silane surface active agent is bonded to the iron plate 12 surface. The monomolecular film 13 is not exfoliated because of its adsorption to the iron plate 12, and it is colorless and transparent and hence does not reduce reflective heat for effective cooking. Since the monomolecualr film 12 has a water repulsive property and hence does not produce any rust owing to moisture in a cooking device. Further, any contamination upon cooking is prevented, and it is simply removed if any.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to household and commercial cooking appliances such as toaster ovens, microwave ovens, and roasters, and in particular to prevention of dirt and rust that occurs during cooking.
The present invention also relates to a heating cooker using a metal inner casing that does not impair heat reflection on the surface of the inner casing due to this treatment.

0002

BACKGROUND OF THE INVENTION Conventionally, metal plates such as iron plates, aluminum, and stainless steel plates have been used as inner casings of cooking appliances. In addition, due to the nature of heating cookers, dirt from the food being cooked is likely to be generated during heating, so some models have a catalyst coated on the surface of the inner casing in order to decompose the dirt that has adhered to the inside of the cooker. Ta.

0003

[Problem to be Solved by the Invention] However, with the conventional metal inner casing, there was a problem in that if food sticks or burns during use of the cooker, it is difficult to remove it. . Additionally, some devices have a catalyst coated on the surface to break down adhering dirt, but in this case there was a problem in that the reflectance of heat from the inner casing surface decreased, reducing heating efficiency. Additionally, since there is a lot of humidity inside the heating cooker, there is also the problem that the surface of the inner casing is prone to rust.

[0004] The present invention solves the above-mentioned conventional problems.It is difficult for cooking stains to adhere, and even if stains do adhere, the stains can be easily removed, and the heating efficiency due to the above-mentioned antifouling treatment is improved. The purpose of the present invention is to provide a cooking utensil that does not deteriorate and does not cause rust on the surface of the inner casing.

[0005]

[Means for Solving the Problems] In order to achieve the first object, the present invention provides a method in which a silane surfactant having a fluorocarbon group is chemically bonded to a metal surface as a monomolecular film through siloxane bonds. is used as the inner casing of the heating cooker. In addition, in order to achieve the second objective, a substance containing multiple silyl groups is chemically bonded to the metal surface, and a silane surfactant having a fluorocarbon group is added to the metal surface as a cumulative film, and chemically bonded by siloxane bonds. The resulting product is used as the inner casing of the cooking device.

[0006]

[Operation] The inner casing used in the present invention has extremely high water and oil repellency because the silane surfactant is chemically bonded with high density at the molecular level so that fluorocarbon groups are arranged on the surface. Excellent. Furthermore, when a cumulative film is formed using a substance containing multiple silyl groups, the density of fluorocarbon groups is 2 to 3.
This increases the amount of water by about twice as much, making it possible to obtain an inner casing with even better water and oil repellency. In addition, because the metal surface and the monomolecular film or cumulative film are chemically bonded, they will not peel off.
Compared to conventional catalyst coatings, such as "SC Coat" (trade name), it is possible to obtain products with extremely superior wear resistance. Furthermore, since all of the monomolecular films are colorless and transparent, they do not reduce the heat reflection efficiency on the surface of the inner casing, unlike when coating with a catalyst that decomposes dirt. Furthermore, since the monomolecular film has excellent water repellency due to the fluorocarbon groups on the surface, it can sufficiently prevent the surface of the inner casing from rusting due to water vapor generated from the food being cooked while using the heating cooker. can. The silane surfactant having a fluorocarbon group used in the present invention may generally be one represented by the following chemical formula.

F(CF2)m(CH2)nSiRqX3
-q (in the formula m=1 to 15, n=0 to 15, m+n=1
Each integer of 0 to 30 and q=0 to 2 is shown, R represents an alkyl group, and X represents a halogen atom. ) F(CF2)m(CH2)nA(CH
2) pSi(CH3)qX3-q (in the formula m=1-8,
Indicates each integer of n = 0 to 2, p = 5 to 25, q = 0 to 2, X represents a halogen atom or alkoxy, and A represents an oxygen atom (O-), carboxy (COO-), or
Represents dimethylsilylene (-Si(CH3)2-). )
For example, CF3(CF2)7(CH2)mSi
Cl3 (m=1or0) CF3CH2
O(CH2)15SiCl3 CF3(
CH2)2Si(CH3)2(CH2)15SiCl3
F(CF2)4(CH2)2Si(C
H3)2(CH2)9SiCl3CF
3COO(CH2)15SiCl3, etc.

[0008]

EXAMPLES (Example 1) Examples of the present invention will be described below with reference to the accompanying drawings. FIG. 1(a) is an external view of a toaster oven which is an example of the present invention, and FIG. 1(b) is a partial sectional view of the inner casing. In FIG. 1, reference numeral 11 denotes an inner casing using an iron plate. In addition, in FIG. 2, 12 is a metal substrate of the inner casing;
3 is a monomolecular film having water and oil repellency. Hereinafter, an antifouling treatment for the surface of the inner casing 11 will be described when an iron plate is used for the inner casing 11.

An iron plate that has been degreased with trichlorethylene is prepared, and a non-aqueous solvent mixed with a substance containing a fluorocarbon group and a silane group, such as CF3 (CF2)7 (CH2
) 3×10-3~ using a substance represented by 2SiCl3
80 dissolved at a concentration of about 5×1 0-2 mol/l
%n-hexadecane, 12% carbon tetrachloride, 8% chloroform solution was prepared and the iron plate was immersed for about 2 hours.
A natural oxide film is formed on the surface of the iron plate, and since the oxide film surface contains many hydroxyl groups, the chlorosilyl groups of substances containing fluorocarbon groups and silane groups react with the hydroxyl groups, resulting in a dehydrochlorination reaction. occurs, and single molecules of the silane surfactant chemically bond to the iron plate surface.

The monomolecular film thus formed has a thickness of approximately 15 angstroms, and since this monomolecular film is adsorbed to the iron plate through chemical bonds as described above, a grid test was carried out. There was no peeling at all. In addition, since this monomolecular film is colorless and transparent, the heat reflected from the inner casing to the food being cooked does not decrease, resulting in improved cooking efficiency compared to conventional catalysts coated on the inner casing. Get better. The surface of the iron plate covered with the monomolecular film does not rust due to the water repellency of the monomolecular film. Since iron plates can be used in areas that were not previously available, it is possible to provide a cheaper product. In addition, in the present invention, as the silane surfactant having a fluorocarbon group, in addition to those shown in the examples, those shown by the chemical formulas explained in the section of operation may be used.

(Embodiment 2) A second embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a toaster oven similar to that in Example 1, but a toaster oven using an aluminized steel plate for the inner casing 11 will be described. The aluminum surface is hydrophilic, but the proportion of hydroxyl groups is smaller than that of the iron plate surface, but it is not suitable for substances containing multiple silyl groups (e.g., SiCl).
4, or SiHCl3, SiH2Cl2, Cl-(
When immersed in a non-aqueous solvent containing SiCl2O)n -SiCl3 (n is an integer, etc.) for about an hour, a dehydrochlorination reaction occurs on the surface because there are some hydrophilic hydroxyl groups on the surface of the aluminized steel sheet. A silane monolayer of a substance containing a plurality of groups is formed. Furthermore, by substituting a halogen group (for example, a Cl group) in the single molecule with a hydroxyl group, the single molecule of the silane surfactant can be chemically bonded to the metal surface.

The case where tetrachlorosilane is used as a substance containing a plurality of silyl groups will be explained below. An aluminized steel plate that has been degreased with trichlorethylene is treated with 3 x 10-3 to 5 x 10-2 mol/tetrachlorosilane.
80% n-hexadecane dissolved at a concentration of about 12
% carbon tetrachloride, 8% chloroform solution is prepared, and the aluminized steel sheet is immersed in a non-aqueous atmosphere at room temperature for 1 hour to form a monomolecular film of trichlorosilyl groups on the surface of the aluminized steel sheet. Thereafter, in order to remove excess tetrachlorosilane, it is washed with chloroform for 30 minutes, and further washed with water for 15 minutes. This water washing step replaces the chlorosilyl group with a hydroxyl group. In this way, three hydroxyl groups are obtained for each hydroxyl group present on the aluminized steel sheet.

[0013] After that, when a silane surfactant having a fluorocarbon group is chemically bonded by the method shown in Example 1, a water- and oil-repellent cumulative film is formed on the surface of the aluminized steel sheet. be done. By performing tetrachlorosilane treatment in advance in this way, a monomolecular film with three times as many fluorocarbon groups as that without treatment is formed, and it forms a monomolecular film with three times as many fluorocarbon groups on the surface as on an aluminum substrate, compared to a steel plate. Even for materials with a small number of hydroxyl groups, it is possible to create a substrate with sufficient water and oil repellency.

[0014] Furthermore, since the cumulative film of this example is also colorless and transparent, the heat reflected from the inner casing to the food to be cooked does not decrease, and compared to the case where the inner casing is coated with a conventional catalyst. ,
Improves cooking efficiency. In order to confirm the water and oil repellency inside the heating cooker using the substrate created in this way for the inner casing, we tested an untreated toaster oven and a toaster oven whose inner casing was coated with a catalyst that decomposes dirt. , and the one in which a monomolecular film was chemically bonded to the surface of the inner casing of the present invention, and the effect on the toasting quality of bread was measured. (Table 1) shows the time required to bake the same amount of bread to a certain color using each toaster oven.

[0015]

[Table 1]

As can be seen from this table, the toaster oven of the present invention has no difference in cooking time compared to an untreated one, and has better cooking efficiency than one whose inner casing is coated with a catalyst. You can see that it is happening. In addition, when we conducted an accelerated test for burnt bread using the toaster oven of the present invention and an untreated one, we found that the inner casing of the toaster oven of the present invention was less likely to attract dirt than the untreated one; Dirt was much easier to remove when the inner casing was wiped with a dry towel. Note that this method of improving water and oil repellency through tetrachlorosilane treatment can also be applied to copper and stainless steel substrates, which have a small proportion of hydroxyl groups on their surfaces, similar to aluminum. Further, although the toaster oven has been described in Examples 1 and 2, it goes without saying that the present invention can also be applied to roasters and microwave ovens having similar inner casings.

[0017]

[Effects of the Invention] As described above, the heating cooker of the present invention, which has an inner casing whose surface has been treated to be water- and oil-repellent, prevents dirt generated during cooking from adhering to the surface of the inner casing. Since dirt can be easily removed, it is possible to keep the interior of the cooker extremely clean. Further, by using this inner casing, the reflection of heat inside the refrigerator is not hindered, and rust can be prevented inside the refrigerator even in a humid cooker.

[Brief explanation of the drawing]

[Fig. 1] (a) is an external view of a toaster oven in the first and second embodiments of the present invention; (b) is a sectional view of the inner casing in the same embodiments;

[Explanation of symbols]

11 Inner case 12 Metal substrate 13 Monolayer

Claims (2)

[Claims] 1. A cooking device using, as an inner casing, a monomolecular film of a silane surfactant having a fluorocarbon group chemically bonded to a metal surface. [Claim 2] A material in which a substance containing a plurality of silyl groups is chemically bonded to a metal surface, and a silane surfactant having a fluorocarbon group is chemically bonded as a cumulative film to the metal surface to which the substance is chemically bonded. A heating cooker using as the inner casing.