JPS6036153A - Water-leakage preventive or water repellent foam molding - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a leakage-preventing or water-repellent foam molded article having a waterproof layer, and more specifically, for example, a waterproof foam molded dew tray for a heat exchanger for air conditioning or air conditioning, and a waterproof foam molded product. The present invention relates to a foam molded article having a waterproof layer, such as a body container.

A dew pan for a cooler or refrigerator is required to be waterproof because it receives water droplets that condense on the heat exchanger of the cooler indoor unit. Furthermore, the outer surface of the saucer must have a structure that prevents condensation from forming due to the cooling effect of cold air or condensed water from the heat exchanger.

Conventionally, the structure of the dew pan is such that there are no parts P that come into contact with cold air or condensed water.
The main body of fr is made of rigid injection molded product such as A J3 S resin, and the outside is made of expanded polystyrene,
It has a double structure covered with a heat insulating material such as urethane,
These have drawbacks such as a complicated manufacturing process, 1] heavier weight, and a higher manufacturing defect rate.

In order to eliminate these drawbacks, some foamed polystyrene surfaces are coated with a mixture of paraffin wax and ethylene vinyl acetate copolymer (Japanese Patent Application No. 1983).
-29533), these were also unsatisfactory in the water leakage test, and water leaked within one hour, resulting in unsatisfactory results.

The present invention was achieved as a result of intensive research in order to improve the above-mentioned drawbacks, and the present invention is made by applying polyvinylidene chloride resin, acrylic resin, polyamide resin, epoxy resin, or Leak-preventing or water-testable foam molding having a waterproof layer formed by coating one or more waterproofing agents selected from the group consisting of methylpolysiloxane alone or a mixture of a substance having an affinity with the waterproofing agent. The body is the content.

Various resins such as polystyrene resins and polyolefin resins can be used as the foam molded article, but styrene resins are more preferable in terms of rigidity, and heat-resistant styrene resins are particularly used. Examples include a copolymer of σ-methylstyrene and styrene, a copolymer of methyl methacrylate, monomethylstyrene and styrene, or a copolymer of styrene and maleic anhydride.

The waterproof paint applied to the foam molded product must be a paint that does not damage the surface of the molded product, and the waterproof dew pan for the heat exchanger must be a paint that can withstand temperatures of 80 to 90°C. Suitable materials include vinylidene chloride latex, cross-linked acrylic resin or a paint mixture of this and varnish, polyamide resin or a paint made of this and a cationic activator, and epoxy resin paint. Paints, methylpolysiloxane resin paints, especially paints containing zinc fatty acids and non-ionic activators, which are superior in water leakage prevention and water repellency compared to other comparative examples, as shown in the test results described below. It is. Furthermore, among these Examples, Example 2 (
Crosslinked acrylic resin-varnish coating No. 1) and Example 4 (epoxy two-component coating) are particularly preferred.

A more favorable effect can be obtained by mixing or dissolving a substance that has an affinity with the waterproof substance and with the base resin of the molded body into the waterproof substance and applying and impregnating it on the foam molded body. can get. When the foamed molded product is a polystyrene-based resin, materials that have an affinity for waterproof substances include polystyrene, copolymers with monomers that can be copolymerized with polystyrene, and materials that are compatible with polystyrene such as polymethyl methacrylate. Inorganic powder substances such as polymers, copolymers and zinc oxide, organic metal salts such as fatty acid zinc and stearic acid/calcium chloride, nonionic activators, cationic activators, varnish, etc. are used. When the foamed molded product is a polyolefin resin, polymers and copolymers compatible with polyolefins such as polyethylene, polyethylene copolymers, polypropylene and polypropylene copolymers, and polypentenamers are used as substances that have an affinity with waterproof substances. Inorganic powder substances such as zinc oxide and organic metal salts such as fatty acid zinc are used.

Coating, dipping,
Spray up, etc.

The water leakage-preventing or water-testing foamed molded product of the present invention can be used in various applications such as water-leakage-preventing foamed molded containers and water-repellent surfing boards, in addition to the above-mentioned dew pans for coolers or air conditioners.

Next, waterproof test results will be described for examples and comparative examples of containers, which are examples of foamed molded products having a waterproof layer of the present invention.

Examples 1 to 5, Comparative Examples j to 3 (a) Waterproof test container (1) Container 40 times expanded polystyrene waterproof container inner dimensions 3
38 x 238 x 100 pieces, 30 pieces for each part (2) Solution Luna Mild [Product name, chemical soap ■] (Luna Mild is a higher alcohol-based (anion) and fatty acid-based (nonionic) surfactant concentration of 32 cm) (3 ) Water depth: 2cm (4) Time-dependent change test in shallow water left at room temperature / / / (b) Waterproofing agent used and test result table]

[Brief explanation of the drawings] The drawings show the water leakage prevention or] odor-based water-based foam molding of the present invention.
Figure 1 shows the front view of the cooler condensation tray (2), (J3) l
r↓Cross-sectional view, FIG. 2 is a cross-sectional view of the water leakage prevention container. (1)...Foamed molded product, (2)...Waterproof layer, (3
)...Support part, (4)...Drain pump. Special No. 87 [Applicant Kanebuchi Chemical Industry Co., Ltd. Agent Patent Attorney Makoto Asano

Claims (1)

[Claims] 1. One or more waterproofing agents selected from the group consisting of polyvinylidene chloride resins, acrylic resins, polyamide resins, epoxy resins, and methylpolysiloxanes are applied to the front and back surfaces of the foam molded product. A leak-preventing or water-testable foamed molded article having a waterproof layer coated alone or in a mixture with a substance having an affinity for the waterproof layer.