JPS62130825A - Cylindrical expansion-molded body and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide a cylindrical foam with a semicircular or semielliptical arcuate part which is excellent in sealing effect, by a method wherein a foam sheet with no skin is folded into circular or elliptical shape and the folded inner sides are bonded together and finally cut off in parallel to the longitudinal direction. CONSTITUTION:Foam or natural or synthetic rubber, foam of polyethylene or polyurethane or the like is used as a foam 1. General purpose adhesive or hot melt adhesive, double-coated adhesive tape may be used as an adhesive bond 3. Sticking layer 13b is applied on the top surface of a foam sheet 5 by feeding an adhesive tape 13 which is produced by applying the sticky layer 13b on a strippable paper carrier 13a, and, after that, the strippable paper carrier 13a is stripped from the sticky layer 13b. The resultant foam 5, onto which the sticky layer is applied, is carried with carrying rolls 10, folded with forming rolls 6 and 6' to inner surface side, formed with side rolls 7 into circular or elliptical shape and finally compressed with compression rolls 9 to be bonded together. The cylindrical expansion-molded body formed as described above is bisected in the longitudinal direction with a cutter 4 in order to obtain final products 8.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a foam columnar molded article suitable as a sealing material and a method for producing the same.

BACKGROUND OF THE INVENTION Conventionally, semicircular or semielliptical columnar foams of rubber or synthetic resin foams have been manufactured using molds.

In the case of rubber foams, thermoforming is carried out in a mold, and in the case of polyurethane foams, liquid raw materials are injected into a mold and cast molding is carried out.

However, since molding using these molds requires individual molds, it is not only expensive as it requires a large number of molds for mass production, but also has the disadvantage that continuous manufacturing is impossible and inefficient. was there.

The present inventor has attempted to improve this drawback.As a result of research, the present inventors first continuously folded a rubber or synthetic resin skinned foam sheet into a semicircular or semielliptic shape with the skin on the outside, and By bonding with adhesive, the arc-shaped parts of the foam are covered with a skin, and a skin with excellent sealing properties is formed, which has an adhesive layer that extends along the pillars toward the top at almost right angles to the center of the bottom, and does not reach the top. We have developed the ability to produce foamed columnar molded bodies (Japanese Patent Application No. 58-244870). However, it has been found that this foamed columnar molded article with a skin has the following problems.

(1) If the sealed portion with which the sealing material comes into contact has unevenness, the skin is difficult to stretch, and a space is created on the sealing surface.

(2) When attempting to insert the sealing material into the gap between the sealed parts by pressing it from the side, if the sealed part is made of a non-slip material, the skin will adhere to the sealed part, making it difficult to insert the sealing member. There were drawbacks.

OBJECT OF THE INVENTION The present invention aims to eliminate this drawback, and its purpose is to prevent spaces from forming on the sealing surface even if the sealed part has irregularities or is made of a non-slip material. It is an object of the present invention to provide a columnar foam having a semicircular or semielliptical arcuate portion that is easy to use and has an excellent sealing effect. Another object of the present invention is to provide a manufacturing method that allows the columnar foam as described above to be manufactured continuously without the need for a mold.

Structure of the Invention The present inventor found that the above-mentioned drawbacks can be overcome when using a foam without a skin,
The present invention was completed based on this knowledge. The gist of the present invention is as follows. A foamed columnar molded product having an adhesive layer that extends almost perpendicularly to the center of the bottom surface toward the top and does not reach the top. and (2) semicircular or elliptical foam, characterized by folding a foam sheet without a skin into a circular or oval shape, gluing the folded inner surface, and then cutting approximately parallel to the length direction. A method for producing a columnar molded body. It is in.

The foam of the foam sheet used in the present invention has a density of 0.01 to 0.4 y7'cm, and a density of 50
It is preferable that the hardness at % compression is 20 to 500 f/Cm2.

If the density is less than 0.0197cm3, the sealing effect will decrease significantly over a long period of time, and if the density is less than 0.0197cm3,
If the sealing material exceeds ', it will be difficult to compress the sealing material when it is pressed diagonally from the side and inserted into the gap, making it difficult to set it completely.

Additionally, if the hardness at 50% compression is less than 20 f//cm2, it will be sufficiently pressed into the gap between the materials to be sealed.
Water leaks from the contact area. Further, if the pressure exceeds 500 f/cm2, the material to be sealed is hard and cannot be compressed when inserted, so it is difficult to insert it. Therefore, it is desirable that it be within the above range.

As a semicircular or semielliptical foam columnar molded product, when the height of the arc shape is b and the length of the bottom surface is a, 1.4>
->0.8 is preferable.

If = is smaller than 0.8, (1) the formed bottom surface will be convex and it will be difficult to form a straight line, so an extra cutting process will be required to make it straight, which will complicate the manufacturing process accordingly. (2
) The edge of the bottom surface is stressed outward, and the adhesive surface tends to peel off. If this peeling is to be prevented, it is necessary to hold it in that shape for a long time, which impairs productivity. (3) Since the height of the arc becomes too low and becomes flat, the sealing effect due to the use of the arc is also reduced.

If - exceeds 1.4, there will be a drawback that the extrusion tip will fall backwards when inserted into the gap between the sealing material.

This range is particularly desirable in cases where there is a large gap, such as between an automobile air conditioner's blower and a cooling unit, or a cooling unit and a heater unit.

The present invention will be explained based on the drawings. Figure 1 is a side view of the foam columnar molded product of the present invention, and Figures 2, 4, and 5 are outlines showing embodiments of the method for manufacturing the molded product of the present invention. It is an explanatory diagram.

In FIG. 1, 1 is a rubber or synthetic resin foam (hereinafter simply referred to as foam), 2 is a bottom surface, and 3 is an adhesive layer. The foam 1 may have a semicircular shape, a semielliptical shape, a combination of both, or an open cell or a closed cell.

Foams include natural rubber and synthetic rubber! Examples include polyolefin foams such as polyethylene, polypropylene, polyethylene/propylene, and polyurethane foams. When a polyurethane foam is used as a water sealing material, it is preferably a polyurethane made from a hydrophobic polyol, such as polybutadiene polyurethane or dimer acid polyurethane. In addition, even if it is a general-purpose polyurethane raw material, it is mainly composed of polyether polyol or polyester polyol obtained by addition polymerization of 90 mol % or more of alkylene oxide having 3 or more carbon atoms, polyester polyol, or a mixture of both, and a polyisocyanate compound. Open cells obtained by foaming with the addition of one or more substances selected from a substance consisting essentially of hydrocarbons, animal and vegetable oils, and dialkyl phthalates having a boiling point of 150 t: or less and a boiling point of 2001: or more at normal pressure. Polyurethane foam may also be used.

However, in the case of air sealing material, general-purpose polyurethane foam may be used. For the contact layer, a general-purpose adhesive may be used, or hot melt adhesive and double-sided adhesive tape may be used.
Alternatively, the surface of the foam may be melted and bonded by heat.

Next, an embodiment of the method for manufacturing a foamed columnar molded article of the present invention will be described based on FIG. 2.

FIG. 2A is a plan view, and FIG. 2 is a side view.

In the figure, reference numeral 5 designates a foam sheet, on which an adhesive tape 13 with a release paper 13a applied to the adhesive layer 13b is supplied from an adhesive tape roll 12 to apply the adhesive layer 13b, and the release paper 13
Peel off a. The foam 5 coated with the adhesive layer is transported by a transport roll 10, bent inward by forming rolls 6 and 6', formed into a circular or oval shape by side rolls 7, and compressed by compression rolls 9. and glued.

In this case, the joints of the ends 5 a + 5 b of the foam are contacted but do not need to be glued. FIG. 3 shows a circular or elliptical foamed columnar molded product formed by compression bonding by the above-described method, and is divided into two lengthwise with a cutter 4 to obtain a final product 8. In the figure, 5 a + 5 b is the foam end;
3 is an adhesive layer.

FIG. 4 shows an embodiment in which adhesive is applied to the folded inner surface of a foam, with FIG. 4A being a plan view and FIG. 4B being a side view. The foam sheet 5 is conveyed by means of a conveyor roll 10 and is folded to the inner side by means of forming rolls 6.6'. When there is still an opening, an adhesive liquid 14, such as a hot melt adhesive liquid, is supplied through a transport hose 15 to apply the adhesive to the inner surface, and then compressed and bonded by a compression roll 9.

FIG. 5 is a side view of an embodiment in which adhesive tape is attached to the bottom surface.

The product 8 is transported by a transport roll 10, the bottom surface is cut with a cut knife 11 to remove a cut piece 16 if necessary, and an adhesive tape 13 consisting of an adhesive layer 13b and a release paper 13a is applied to the cut surface of the adhesive roll 12. The adhesive layer 13b of the adhesive tape is applied by pressing with a pressure roll 17. This yields a product 18 with adhesive tape.

When using this, it can be used for adhesion to the other substrate by peeling off the release paper, and also acts to reinforce the adhesive layer. Therefore, if it is convenient to use adhesive on the bottom of the product, it is preferable to attach adhesive tape in this manner.

Effects of the Invention When the foamed columnar molded article of the present invention is used as a backing material, (1) Since its shape is semicircular or semielliptical, when it is pressed from the side into the gap between the parts to be sealed and set, it cannot be sealed. The material can be easily inserted without being pushed down, and even when the material of the sealed member is not easily slippery, the material can be easily inserted without being pushed down.

(2) Since the molded body has an adhesive layer in the center of the bottom surface toward the top, when it is compressed from the top (upper surface), the adhesive layer acts as a spring and prevents it from falling down. It has rigidity in the parallel direction, and when it is compressed during sealing, it increases the adhesion to the part to be sealed, and the adhesive layer is highly compressed to enhance the sealing effect.

Furthermore, in the direction perpendicular to the adhesive layer, it is flexible and has excellent fit around curved parts.

(3) Since there is no skin on the surface of the foam sheet, even if the surface of the part to be sealed is uneven and not smooth,
The foam can be filled up to the gaps between the concave and convex portions.

Furthermore, even if the material of the sealed portion is difficult to slip, it can be easily inserted into the gap without falling over.

(4) It does not require a mold and can be manufactured easily and continuously.

It has excellent effects such as

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a foam columnar molded article without a skin of the present invention;
FIG. 2 and FIG. 4 are embodiments of the method for manufacturing a molded body of the present invention, and FIG. 3 is a cross-sectional view of an elliptical foam columnar molded body.
Each of FIGS. 2 and 4 shows a plan view thereof, each B shows a side view thereof, and FIG. 5 shows an embodiment in the case where an adhesive tape is provided on the bottom surface. 1: Foam, 2: Bottom surface, 3: Adhesive layer, 4: Knife, 5: Foam sheet without skin, 5a+5b: Foam sheet end, 6, 6': Molding coal, 7 = Guide roll, 8
: Product, 9: Compression roll, 10: Conveyance roll, 11: Cut knife, 12: Adhesive tape roll, 13: Adhesive tape, 13a: Release paper, 1
3b=Adhesive layer, 14: Adhesive liquid, 15: Transport hose, 16: Cut piece, 17: Pressure roll, 1
8; Product with adhesive tape.

Claims (1)

[Scope of Claims] 1) Consisting of a semicircular or semi-elliptical columnar body made of rubber or synthetic resin foam, having no skin on its surface, and extending along the columnar shape toward the top at approximately right angles to the center of the bottom surface; A foam columnar molded product with an adhesive layer that does not reach . 2) The density of the rubber or synthetic resin foam is 0.01 to 0.
4g/cm^3 and hardness at 50% compression is 20
The foamed columnar molded article according to claim 1, which has a weight of 500 g/cm^2. 3) The foam columnar molded article according to claim 1 or 2, wherein 1.4≧(arc shape height/bottom length)≧0.8. 4) A semicircular or semielliptical foam column characterized by folding a foam sheet without a skin into a circular or oval shape, gluing the folded inner surface, and then cutting almost parallel to the length direction. Method for manufacturing molded bodies.