JP3061336B2 - Hydrophilic treatment agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a treating agent having hydrophilic properties.

[0002]

2. Description of the Related Art Heretofore, as this kind of treating agent, a substance obtained by dissolving or dispersing silicon oxide as a solid content in a solvent such as an alcohol solution or dimethylacetamide has been used.

[0003]

However, for example, in the case of an inner container of an electric water heater, such a conventional treating agent is applied on the first coating layer containing fluorine as a main component and a hydrophilic treatment layer is applied. Even if water is formed, if a conventional hot-water boiling with a citric acid solution (hereinafter referred to as citric acid treatment) is performed to remove scales adhered by repeated boiling, the hydrophilically treated layer is destroyed together with scale removal. You.

[0004] In the case of boiling water, silicon oxide forming the hydrophilic treatment layer reacts with scale components such as calcium and magnesium contained in tap water to produce components easily dissolved in citric acid. It is thought to be because.

[0005] For this reason, when water is heated again after the citric acid treatment, an air layer is generated between the heated surface and water due to the deterioration of the hydrophilic property of the coating surface due to the destruction of the hydrophilic treatment layer, and the air-burning state is caused. When the density is high, there has been a problem that abnormal detection of the sensor and discoloration of the coating occur due to a remarkable temperature rise of the heating surface.

An object of the present invention is to solve the above-mentioned problems, and to provide a treating agent which retains a hydrophilic treatment layer even after a citric acid treatment for removing water scale, secures hydrophilic performance, and improves reliability and durability. It is an object.

[0007]

According to the present invention, in order to achieve the above object, polyethersulfone or silicon oxide and polyethersulfone are used as solids, and dimethylacetamide or N-methyl- 2
-Pyrrolidinone, or a hydrophilic treatment agent using dimethylacetamide and N-methyl-2-pyrrolidinone.

[0008]

According to the present invention, polyethersulfone or silicon oxide and polyethersulfone are used as solid components in the above-mentioned means for solving the above problems, and the polyethersulfone does not react with the scale component. Adhesive strength can be further improved, and by mixing silicon oxide and polyethersulfone at an appropriate mixing ratio depending on the type of the first coating layer, adhesion can be further improved and noise can be reduced. Hydrophilicity can be ensured even after boiling with a citric acid-treated solution.

Dimethylacetamide as a solvent;
Alternatively, N-methyl-2-pyrrolidinone, or dimethylacetamide and N-methyl-2-pyrrolidinone are used, and dimethylacetamide can improve the solid content and the adhesion to the first coating layer. In addition, N-methyl-2-pyrrolidinone has a higher boiling point than dimethylacetamide, and the solvent does not easily fly during firing, so that the solid content and the adhesion to the first coating layer can be further improved.

In addition, the adhesion can be improved by mixing dimethylacetamide and N-methyl-2-pyrrolidinone at an appropriate mixing ratio depending on the type of the first coating layer. N after flying
Since -methyl-2-pyrrolidinone flies, pinholes, cracks, blisters and the like are suppressed, and a stable hydrophilic treatment layer can be formed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 1, reference numeral 1 denotes an exterior body, in which a bottomed cylindrical container 2 is housed. On the inner bottom surface 2a of the container 2, a polyethersulfone or a silicon oxide and a polyethersulfone as a solid content are coated on the first coating layer 3 mainly containing fluorine and polyethersulfone, and The hydrophilic treatment layer 4 is formed by applying dimethylacetamide, N-methyl-2-pyrrolidinone, or a treatment agent that provides hydrophilic performance using dimethylacetamide and N-methyl-2-pyrrolidinone.

The first coating layer 3 and the hydrophilic treatment layer 4 were formed as follows. First, a paint prepared by dissolving fluorine and polyethersulfone in a solvent is applied, and after drying at about 150 ° C., as a solid, polyethersulfone or silicon oxide and polyethersulfone are used as solvents. A first coating film is obtained by applying a treatment agent that provides hydrophilic performance using dimethylacetamide, N-methyl-2-pyrrolidinone, or dimethylacetamide and N-methyl-2-pyrrolidinone, and then firing at about 350 ° C. Layer 3 and second coating layer 4
Was formed.

On the back side of the bottom surface of the container 2, a heating element 5 is pressed and fixed by a back plate 6. Reference numeral 7 denotes a control board, which controls energization of the heating element 5 by an electric signal from the temperature detecting device 8.

In the above configuration, when the liquid is stored in the container 2 and the energization is started, the heating element 5 is heated to heat the liquid in the container 2, and the predetermined temperature is detected by the temperature detecting device 8 attached to the lower part of the container 2. It is controlled to the liquid temperature.

Here, in the embodiment, on the first coating layer mainly containing fluorine and polyethersulfone,
Polyethersulfone or silicon oxide and polyethersulfone as solids, dimethylacetamide or N-methyl-2-pyrrolidinone as a solvent,
Alternatively, a hydrophilic treatment layer 4 is formed by applying a treatment agent that provides hydrophilic performance using dimethylacetamide and N-methyl-2-pyrrolidinone, and a scale component such as calcium or magnesium contained in tap water is formed. Since a component that does not react and easily dissolves in citric acid is not generated, even if a boiling process is performed with a citric acid solution for removing scales adhered by repeated boiling, the hydrophilic treatment layer 4 remains and hydrophilic performance can be secured. Therefore, reliability and durability can be improved.

[0017]

As is apparent from the above description of the embodiment, the present invention provides polyether sulfone or silicon oxide and polyether sulfone as solids on the first coating layer as a solvent. A hydrophilic treatment layer is formed by applying a treatment agent that provides hydrophilic performance using dimethylacetamide, or N-methyl-2-pyrrolidinone, or dimethylacetamide and N-methyl-2-pyrrolidinone, and the hydrophilic treatment layer is formed. Does not react with scale components such as calcium and magnesium contained in tap water, and does not produce components that are easily dissolved in citric acid.

Therefore, even if the water is heated with a citric acid solution for removing water scale adhered by repeated water boiling, the hydrophilic treatment layer remains and the hydrophilic performance can be secured, so that the reliability and durability can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of an electric water heater according to an embodiment of the present invention.

FIG. 2 is a partially enlarged view of a bottom portion of the container of the electric water heater.

[Explanation of symbols]

 2a inner bottom surface 3 first coating layer 4 hydrophilic treatment layer

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Hidenori Kawanishi 1006 Kadoma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. In-company (72) Inventor Maeda Maeda 1006 Kadoma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. Inventor Yoshiho Nodo 1006 Kazuma Kadoma, Kadoma City, Osaka Inside Matsushita Electric Industrial Co., Ltd.

Claims (1)

(57) [Claims] 1. A port re polyether sulfone or includes a silicon oxide and polyether sulfone, consists of dimethylacetamide and N- methyl-2-pyrrolidinone
A hydrophilic treatment agent comprising at least one selected from the group .