JP3163430B2 - Tubular body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tubular body constructed as a pipe for cooling air or refrigerant in an air conditioner or the like, and more particularly to a tubular body for efficiently absorbing water droplets generated on the surface.
It relates to a tubular body that does not drip .

[0002]

2. Description of the Related Art As a tubular body of this type, there is a tubular body composed of a synthetic resin in which a synthetic resin containing a highly water-absorbing polymer is arranged on an outer surface layer (Japanese Patent Laid-Open No. 62-22 / 1987).
No. 8783).

[0003]

In such a tube in which a synthetic resin containing a superabsorbent polymer is disposed on the outer surface layer of a tubular body, the superabsorbent polymer itself has a weight ratio of 1%.
It has a high water-absorbing ability to absorb 0 to 1500 times the water content, but since the super-absorbent polymer itself is contained in the synthetic resin, the force of the super-absorbent polymer to expand is reduced. , Is suppressed by the surrounding synthetic resin, and its original absorption ability is reduced. Further, since the outer surface layer of the tubular body is made of a synthetic resin containing a highly water-absorbing polymer, the heat insulating property is poor, and dew condensation easily occurs on the outer surface. Furthermore, it is also to have the disadvantage that the temperature of the cold air and the refrigerant of the air conditioner or the like flowing through the inside of the tubular body is increased.

Accordingly, the present invention is to provide a tubular body which has a sufficient water absorption capacity, does not drop water drops during use, and does not raise the temperature of cold air or refrigerant in an air conditioner or the like flowing inside. It is intended for.

[0005]

Means for Solving the Problems In order to achieve the above object, the present invention relates to a tubular body having a water absorbing layer formed on the surface of a tubular body made of synthetic resin, wherein the water absorbing layer is made of acrylic fiber.
By hydrolyzing the fiber surface with sodium hydroxide
Sodium acrylate, a highly water-absorbing polymer for the outer layer
Polymer and the core remains acrylic fiber
Fibers and carboxymethy
Regenerated cellulose made from rucellose sodium salt
5 to 1000 times the water content of fiber by weight
Highly water-absorbing fibers that retain high water absorption capacity
Characterized by being configured in fabric having in the brick
It is a tubular body.

[0006] The present invention also relates to a synthetic resin comprising:
In a tubular body having a water absorbing layer formed on the surface of the tubular body,
With a vinyl alcohol unsaturated carboxylic acid polymer,
Tylene-maleic anhydride polymer, acrylic acid-acrylic
Weight ratio of luamide polymer, polyacrylic acid polymer, etc.
High water absorption that absorbs 10 to 1500 times more water
Super absorbent poly which retains its function but does not substantially dissolve in water
In a fabric that contains and fixes the
It is a tubular body characterized by comprising.

As the fabric , the outer layer is made of a sodium acrylate polymer which is a highly water-absorbing polymer by hydrolyzing the surface of the acrylic fiber with sodium hydroxide, and the core is left as an acrylic fiber to obtain strength. Is preferably a two-layered fiber holding
Is a fiber or the like made of regenerated cellulose made of sodium salt of carboxymethyl cellulose, and has a weight ratio of 5%.
A highly water-absorbing fibrous material that retains a high water-absorbing ability to absorb twice to 1000 times as much moisture is also conceivable. Examples of the highly water-absorbing granular polymer contained in the fabric include vinyl alcohol-unsaturated carboxylic acid polymer , An isobutylene-maleic anhydride polymer, an acrylic acid-acrylamide polymer, a polyacrylic acid polymer, and the like, which retains a high water-absorbing ability to absorb 10 to 1500 times by weight of water. Superabsorbent polymer that is practically insoluble in water.

[0008] The fabric is preferably a nonwoven fabric formed by joining mats or thin cotton-like synthetic fibers or natural fibers with each other by an adhesive or the fusion force of the fibers themselves. Rukoto contain a particulate polymer Ru also considered. When containing highly water-absorbing fibers, a non-woven fabric is formed by joining the highly water-absorbing fibers formed in a mat or thin cotton, or such a mat or thin cotton-like high water absorbing fiber and another the mat-like or thin cotton-like synthetic fibers and natural fibers was mixed formed nonwoven, but can be formed in a mat shape or a thin cotton-like nonwoven fabric by mixing a superabsorbent fibers and other synthetic fibers and natural fibers .
When containing a highly water-absorbing granular polymer, a highly water-absorbing granular polymer is added to the above-mentioned synthetic fiber or natural fiber by mixing the highly water-absorbing granular polymer with a mat-like or thin cotton-like synthetic fiber or natural fiber. Use a non-woven fabric by bonding. The content of that is contained in the fabric of highly absorbent fibers or the superabsorbent particulate to polymer fabric, preferably in the range 1 to 70% based on the weight of the total fabric, more preferably at 3-50% is there. If the content is less than 1%, sufficient water absorption capacity cannot be obtained, and if it exceeds 70%, no increase in water absorption capacity is observed, and the content of highly water-absorbing fibers or highly water-absorbing granular polymer Effect cannot be obtained.

As the synthetic resin constituting the tubular body, a polyolefin such as polypropylene or polyethylene is used, and as the fiber constituting the nonwoven fabric, a thermoplastic synthetic resin is preferable. Further, the same polyolefin such as polyethylene or polypropylene as the tubular body is used. It is preferable to configure with. By doing so, the recyclability is improved, and the burr portion can be reused.

[0010]

According to the present invention, as described above, when moisture adheres to the water-absorbing layer, the highly water-absorbing fiber or the highly water-absorbing granular polymer can be sufficiently swollen, and the high water-absorbing polymer can be obtained. An original large swelling ratio can be obtained.
Therefore, it can absorb very much water,
Water does not drip from the surface of the tubular body during use. Further, since the water-absorbing layer is made of a fabric having an air portion between fibers, the heat-absorbing layer has a high heat insulating property and can suppress the temperature of the fluid inside the tubular body from flowing out. The fabric can be integrally formed at the time of molding, is easily welded to the tube, and does not peel off.

[0011]

EXAMPLES-out group Dzu an embodiment in the drawings of the present invention will be described. FIG. 1 is a perspective view illustrating a tubular body 1 of the present invention. The tubular body 1 includes a tubular body 2 and a water absorbing layer 3 formed on the surface thereof. The tube 2 is made of polypropylene , and a highly water-absorbing granular polymer is formed on the surface of the tube 2.
Fabric made of non-woven fabric as water-absorbing layer 3
That features together.

As the highly water-absorbing granular polymer, Sumikagel NP-1020 (trade name, manufactured by Sumitomo Chemical Co., Ltd.) was used. This is a sodium acrylate polymer having a carboxylic acid sodium group, particle size 10 to 30
μm. As the fabric, a 3-denier polypropylene fiber was formed in a mat shape, the above-mentioned highly water-absorbing granular polymer was contained and fixed therein, and a nonwoven fabric was formed by a dry method. At this time, the content of the superabsorbent granular polymer contained was 30% of the weight of the whole fabric.
%.

In the production of the tubular body 1, the above-mentioned two divided fabrics were placed in a divided mold, and polypropylene was extruded and blow-molded to be simultaneously and integrally molded. The tubular body 1 was mounted in an engine room and a vehicle as a duct of an air conditioner of an automobile, and the state of water droplets adhering to the surface was observed. At this time, the diameter of the tubular body 1 is 50 m.
m, the thickness of the tube 2 is 2 mm, and the thickness of the water absorbing layer 3 is 0.7.
mm.

[0014] The tubular body 1, air temperature 30 ° C., 80% humidity
R. H. In the atmosphere, cool air at a temperature of 4 ° C.
The tube was introduced for a period of time and passed therethrough, and the state of the surface of the tubular body 1 was observed.
Further, for comparison, a tubular body made of only a polypropylene tubular body having a thickness of 2 mm without a water absorbing layer (Comparative Example 1)
And a water-absorbing layer with a highly water-absorbing polymer (Sumikagel NP-10)
A similar experiment was conducted using a sample (Comparative Example 2) in which an ethylene-vinyl acetate copolymer (vinyl acetate content: 25 mol%) containing 50) by weight of 20) was disposed.

The tubular body of Comparative Example 1 water droplets adhere to the surface,
As the use proceeded, water droplets dropped. Further, the tubular body of Comparative Example 2 is not dripping of water drops in the use of short, the long term use, there was dripping of water drops. This was particularly noticeable in tubulars used in the engine compartment. However, in the tubular body of the example, at the time of the experiment, water droplets were absorbed by the surface layer, and no water droplets were dropped .

[0016]

The present invention is configured as described above.
When moisture adheres to the water-absorbing layer, the superabsorbent fibers or the high-absorbent granular polymer constituting the outer layer can swell sufficiently, and the superabsorbent fibers or the high-absorbent polymer inherently have a very large size. The swelling ratio can be obtained.

Accordingly, it is possible to absorb a very large amount of water, not only to have an effect that it is easily saturated during use and water does not drip from the surface of the tubular body, but also to have a high heat insulating property and to have a tubular body. The heat radiation of the internal fluid to the outside can be suppressed.

[Brief description of the drawings]

FIG. 1 is a perspective view of a tubular body according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tubular body 2 Tubular body 3 Water absorption layer

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B32B 1/00-35/00 F16L 9/00-9/22 F16L 11/00-11/24

Claims (2)

(57) [Claims] 1. A tubular body having a water-absorbing layer formed on the surface of a tube made of a synthetic resin, wherein the water-absorbing layer is formed of an acrylic fiber.
By hydrolyzing the fiber surface with sodium hydroxide
Sodium acrylate, a highly water-absorbing polymer for the outer layer
Polymer and the core remains acrylic fiber
Fibers and carboxymethy
Regenerated cellulose made from rucellose sodium salt
5 to 1000 times the water content of fiber by weight
Highly water-absorbing fibers that retain high water absorption capacity
A tubular body comprising a fabric in a brick . 2. The surface of a tube made of synthetic resin is adsorbed.
In the tubular body with the water layer formed, the water absorption layer is
Cole unsaturated carboxylic acid polymer, isobutylene-anhydride
Ilenic acid polymer, acrylic acid-acrylamide polymer
Weight ratio of polymer, polyacrylic acid polymer, etc.
Although it retains high water absorption capacity, which absorbs 1500 times more water
A superabsorbent granular polymer that is practically insoluble in water
A tubular body comprising a fabric contained and fixed in a fabric .