JPH06798A - Foam cutting method for silicone rubber foam body - Google Patents

Abstract

PURPOSE:To uniformly and efficiently slice a silicone rubber foam body without causing vibration or deformation by manufacturing the silicone rubber foam body in a frame body made of a resin foam body, and slicing the silicone rubber foam body integrally with the frame body. CONSTITUTION:A silicone rubber foam precursor is stored in a frame body 1 with at least the bottom wall and side walls 2a-2d made of a resin foam body. The precursor is foamed in the frame body 1 to form a silicone rubber foam body 11. The silicone rubber foam body 11 thus formed is cut by a cutting means 15 nearly in parallel with the bottom wall from the side face direction of the frame body 1 together with the frame body 1. The silicone rubber foam body 11 can be uniformly and efficiently sliced while no vibration or no deformation is generated.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel method capable of efficiently cutting a silicone rubber foam.

[0002]

TECHNICAL BACKGROUND OF THE INVENTION Silicone rubbers have a very wide temperature range of use as compared with commonly used rubber-like substances, and some of them can be used at temperatures of -100 ° C or lower to + 250 ° C or higher. . Silicone foam (silicone rubber foam), which is a foam of silicone rubber having such characteristics, is excellent in heat resistance, cold resistance, and the like, and since it is a foam, it also has good heat retention and heat insulation properties. .

In recent years, silicone rubber foams have begun to be used as various heat insulating materials, heat resistant materials, interior materials, etc. by utilizing the excellent characteristics of such silicone rubber foams. For example, the fuel tank for automobiles made of synthetic resin, which has been rapidly spreading recently, is
It is often placed on the exhaust gas pipe, and it is necessary to place a heat insulating material between them to protect the fuel tank from heating by the exhaust gas pipe. Since the heat insulating material used here is required to have extremely high heat resistance, a silicone rubber foam is particularly suitable for such an application.

Such a silicone rubber foam is obtained by casting a silicone rubber foam precursor, which is a raw material of the foam, to a predetermined thickness and then expanding the precursor while compressing the precursor to adjust the thickness. Or, after foaming the silicone rubber foam precursor, adjust the foam of the desired thickness by inserting the rotary blade from this horizontal direction into the silicone rubber foam and slicing to the desired thickness. To be done.

However, of the above methods, when foaming into blocks and slicing, since the silicone rubber foam is soft, even if the silicone rubber foam is directly cut, the rotary blade has a silicone rubber foam. It is difficult for the silicone rubber foam to enter, and it is difficult to obtain a smooth cut surface by vibrating the silicone rubber foam by the rotary blade, and the silicone rubber foam is often broken during cutting. Furthermore, there is a problem in that it becomes difficult to cut the silicone rubber foam toward the lower part of the silicone rubber foam, resulting in poor yield.

In order to solve these problems, a method of preventing the silicone rubber foam from shaking by holding both sides of the silicone rubber foam with a holding tool at the time of cutting has been adopted, but this method is very effective. There is a problem of poor workability.

Therefore, the present inventor forms a frame body with plywood, puts the above precursor therein, and foams in this frame body to produce a block-shaped silicone rubber foam body, and removes the frame body. Later I tried to cut this block. In this method, since the silicone rubber foam precursor penetrates into the grain of the plywood constituting the frame, it is necessary to attach release paper to the inner wall of the frame.

However, the manufacturing of the frame itself used in this method is considerably cumbersome, and the frame becomes considerably heavy, which makes it difficult to move. Further, it is necessary to dispose a release paper on the inner wall of the frame, which causes a problem of extremely poor workability. Furthermore, after foaming in the frame body as described above, when the frame body is removed, release paper adheres to the surface of the block-shaped silicone rubber foam, and the release paper causes the block-shaped silicone rubber foam to adhere. Was found to be more difficult to cut. In addition, since this release paper adheres to the silicone rubber foam during foaming, there is another problem that it becomes difficult to remove the release paper from the silicone rubber foam after cutting.

[0009]

OBJECTS OF THE INVENTION It is an object of the present invention to provide a novel method for efficiently cutting a silicone rubber foam.

[0010]

SUMMARY OF THE INVENTION A method for foaming and cutting a silicone rubber foam according to the present invention is a method in which a silicone rubber foam precursor is contained in a frame body having at least a bottom wall and a side wall made of a resin foam, and the precursor is placed in the frame body. Is foamed to form a silicone rubber foam, and the formed silicone rubber foam is then cut together with the frame body from the side surface direction of the frame body substantially parallel to the bottom wall.

In the method of the present invention, since the silicone rubber foam is formed in the frame made of the resin foam and integrated with the frame, and this is cut, the cutting blade easily enters the silicone rubber foam, Further, the silicone rubber foam can be efficiently cut without lateral rolling of the silicone rubber foam during cutting.

[0012]

DETAILED DESCRIPTION OF THE INVENTION Next, the method of the present invention will be specifically described with reference to Examples. As shown in FIGS. 1 and 2, according to the foam cutting method of the present invention, first, the silicone rubber foam 11 is manufactured in the frame 1 made of resin foam.

The frame 1 comprises a side wall 2 and a bottom wall 3. Each wall is formed of resin foam. As the resin foam that forms the side wall and the bottom wall, foams formed of various known resins such as urethane foam, styrene foam, and olefin resin foam can be used. However, the silicone rubber foam cannot be used as the resin foam forming the frame in the present invention.

In the present invention, among these resin foams, urethane foam is preferable. This urethane foam is a polyurethane foam having a urethane bond (-NH-CO-O-). This polyurethane is produced by reacting a polyisocyanate and a polyol.

Examples of polyisocyanates used herein include tolylene diisocyanate, 4,4-diphenylene methane diisocyanate, 1,5-naphthalene diisocyanate, triphenylene methyl triisocyanate, tolylene diisocyanate (TODI), xylene diisocyanate, Hexamethylene diisocyanate (including its modified products), dicyclohexylmethane diisocyanate (hydrogenated MDI) and isophorone diisocyanate (IPDI) can be mentioned.

Examples of polyols include ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, 1,3-butanediol, hexanetriol, trimethylolpropane, glycerin, pentaerythritol, sorbitol and sucrose. .

Polyurethanes can also be made from polyisocyanates and polyesters. The polyester used here is the above-mentioned diol, adipic acid,
It is formed from dicarboxylic acids such as phthalic acid, sebacic acid and dimer acid.

Since isocyanate generates carbon dioxide gas during the reaction, polyurethane can be foamed by utilizing this carbon dioxide gas. In addition, a foaming agent can also be used.

Further, in the present invention, the urethane foam forming the frame may be a crushed product of the urethane foam when the urethane foam is manufactured as described above. That is, in the present invention, the urethane foam which has already been used up, such as used urethane foam and lot-out urethane foam, is crushed and thermocompression bonded to produce a recycled urethane foam product for reuse. be able to. Further, in the present invention, a crushed material of other foamed resin such as styrofoam may be blended in place of or together with the exhausted urethane foam.

A plate-shaped urethane foam is manufactured from the above raw materials. Since this plate-shaped urethane foam constitutes the side wall and the bottom wall of the frame body, a certain degree of strength is required, and the urethane foam used as the bottom wall is usually 10 to 100 mm, preferably 30 to 100 mm.
Make it about the thickness. Further, the side wall 2a in the width direction is 5 to 5
Make it about 0 mm thick. Furthermore, the longitudinal side walls 2c, 2d
Is usually 5 to 40 mm, preferably 8 to 50 mm. By using the urethane foam having such a thickness, the frame body is unlikely to be deformed at the time of foaming and is not easily deformed at the time of slicing, and the slicing is easy. In particular, by making the urethane foam in the width direction in which the blade is inserted 5 to 20 mm thick, preferably 5 to 15 mm thicker than other portions in the width direction, it becomes easier to slice.

A frame body as shown in FIG. 1 is manufactured using the urethane foam having the above thickness. The frame 1 used in the present invention includes at least the bottom wall 3 and the side walls 2a, 2b,
2c and 2d are formed of a resin foam such as the above urethane foam. The frame body is manufactured by placing the bottom wall 3 on a substrate such as plywood and bonding four side walls to the bottom wall 3 with an adhesive or the like. Particularly in the present invention, the frame body 1 made of this resin foam forms the outer frame of the frame body 1 with plywood or the like, and the resin foam body and the side walls 2a, 2b, 2c forming the bottom wall 3 in the outer frame. It is possible to easily manufacture by arranging the resin foam forming 2d, 2d and adhering the joint portion of the resin foam, and then removing the outer frame.

The size of the frame is not particularly limited, but in consideration of the weight of the frame, the efficiency of the foaming reaction, the transportability and the cutting efficiency of the cut silicone rubber foam, it is used for foaming in the frame. The volume that can be formed is preferably about 1 to 500 liters.
It is preferable that the height is about 100 mm, the width is about 100 to 1500 mm, and the height is about 700 mm.

A silicone rubber foaming precursor is placed in the frame 1 as described above, and this precursor is foamed in the frame 1.
Since the silicone rubber foam does not penetrate into the resin foam forming the side wall of the frame at the foaming stage, it is not necessary to attach release paper to the inner peripheral surface of the frame used in the present invention. .

For the silicone rubber foam, RTV (Room
Various foams such as Temperature Vulcanizing) are known, but among them, RTV is a two-liquid type, and since the two liquids are mixed and stirred at room temperature, foaming and hardening occurs within a few minutes. It does not require heating and is suitable for use in the method of the invention. Further, since this RTV is foamed by using hydrogen gas generated during the curing reaction, it is not necessary to specifically mix an additive for foaming such as CFC, which is preferable in terms of working environment.

As the RTV, catalyst systems such as Pt catalyst system, Sn catalyst system, organometallic salt catalyst system, and aminoxy group reaction system are known. In the present invention, any of them is used. The catalyst system or reaction system of the above can also be used. Among them, Pt catalyst type RTV is particularly preferable because it has a good foaming property and good workability.

A silicone rubber foam raw material (silicone rubber foam precursor) capable of producing the above-mentioned silicone rubber foam is put in the frame body, and usually 2 to 20 times, preferably 3 times in the frame body. A silicone rubber foam is produced by foaming at a foaming ratio of about 15 times.

When producing this silicone rubber foam, it is preferable to place the lid 4 on the surface of the silicone rubber foam precursor filled in the frame 1 to foam the silicone rubber foam, as shown in FIG. That is, since the silicone rubber foam is cut horizontally, the loss of the silicone rubber foam due to slicing can be reduced by making the upper surface of the silicone rubber foam produced by reacting in the frame body as horizontal as possible. The lid 4 used here is
Any material can be used as long as it can be floated on the surface of the silicone rubber foam precursor contained in the frame body 1 and can rise to the upper part inside the frame body as the silicone rubber precursor foams, usually about 10 to 100 mm. A resin foam such as urethane foam having a thickness of 10 mm and having a shape that can be inserted into the frame body from the upper opening of the frame body 1 is used.

The foaming time of the silicone rubber foam precursor is
It can be appropriately selected, for example, by changing the composition of the precursor in consideration of the working condition, etc.
It takes about 10 minutes. In the silicone rubber foam thus produced, open cells or closed cells or both open cells and closed cells are formed depending on the expansion ratio.

In the present invention, as shown in FIG. 2, after the silicone rubber foam 11 is manufactured in the frame 1 as described above, the silicone rubber foam 11 is put into the frame 1.
At the same time, cutting (slicing) is performed from the side wall 2a direction to the side wall 2b direction substantially parallel to the lower surface wall. This cutting is the frame 1
This can be done with a cutting means 15, such as a rotary blade or a saw, which is arranged to move relative to it.
For example, the frame 1 may be a horizontal moving device 1 such as a belt conveyor.
First, the frame body 1 and the upper portion of the silicone rubber foam 11 are cut so that the upper surface of the silicone rubber foam 11 from which the lid is removed is exposed horizontally. Next, the frame 1 is moved in the direction of the cutting means 15 (direction of arrow A) rotated by the motor 17 or the like. When the cutting means 15 reaches the side wall 2a, the side wall 2a is cut first, and then the silicone rubber foam 11 together with the frame 1 is sliced from the side wall 2a direction to the side wall 2c direction. When the cutting means 15 reaches the side wall 2c and cuts the side wall 2c, the sliced silicon rubber foam is removed, and the frame body 1 is moved in the opposite direction (direction of arrow B) to return to the cutting start position. Next, the positions of the frame 1 and / or the cutting means 15 are moved up and down in correspondence with the slice thickness, and the frame 1 and the cutting means 15 are set at new cutting positions. After setting the frame body 1 and the cutting means 15 in this way, the silicone rubber foam 11 is sliced together with the frame body 1 in the same manner as above. By repeating this operation, the silicone rubber foam 11 is attached to the lower surface wall 3
Slice one by one until reaching. After cutting in this way, a sheet-like silicone rubber foam having a desired thickness can be obtained by removing the frame body around the cut silicone rubber foam.

The cutting device shown in FIG. 2 shows a mode in which the blade is provided only on one side of the rotary blade, but by providing the blade on both sides, the frame 1 can be moved to the arrow B. You can also slice from the opposite direction when returning to.

By cutting the silicone rubber foam 11 together with the frame body 1 in this manner, the slice thickness of the silicone rubber foam can be reduced, and the slice thickness is 5 mm.
It can be made as thin as possible. Moreover, since the silicone rubber foam is cut together with the frame body, the silicone rubber foam does not vibrate and the cut surface becomes smooth.

In the above description, the case where urethane foam is used as the frame has been mainly described, but the same operation can be performed when a frame made of another resin foam is used.

The sheet-like silicone rubber foam thus obtained can be used for applications such as a heat insulating material, a heat-resistant material, and a heat insulating material in which the silicone rubber foam is conventionally used.

[0034]

According to the method of the present invention, a silicone rubber foam is manufactured in a frame formed of a resin foam such as urethane foam, and the frame body is made of a resin foam such as urethane foam which is easy to cut. After the cutting blade enters the silicone rubber foam, the cutting blade enters and the silicone rubber foam is sliced as a unit with the frame body, so it becomes very easy to slice the silicone rubber foam, and at the time of slicing The silicone rubber foam can be sliced uniformly and efficiently without vibration or deformation.

Moreover, by using the frame body formed of the resin foam such as urethane foam as described above, the bottom of the foam can be sliced without waste and the yield is improved.

Further, the frame used in the present invention can be very easily manufactured by adhering a plate-shaped resin foam, for example. Moreover, since it is not necessary to attach release paper or the like to the inside of the frame body, the frame body can be easily manufactured, and the urethane foam can be easily separated from the sliced silicone rubber foam. In addition, the problem that it is difficult to remove the release paper from the sliced silicone rubber foam is solved. Further, since no release paper is used, the problem that the silicone rubber foam is difficult to cut by the release paper does not occur.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing an embodiment of a foam cutting method of the present invention.

FIG. 2 is a diagram schematically showing an example of a cut state of the foam cutting method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Frame body 2a, 2b, 2c, 2d ... Side wall 3 ... Bottom wall 4 ... Lid body 11 ... Silicone rubber foam 15 ... Cutting means 16 ... Horizontal movement device 17 ... Motor

Claims (3)

[Claims] 1. A silicone rubber foam precursor is contained in a frame body having at least a bottom wall and a side wall formed of a resin foam, and the precursor is foamed in the frame body to form a silicone rubber foam body. A foam cutting method for a silicone rubber foam, which comprises cutting the formed silicone rubber foam together with the frame from a side surface direction of the frame substantially parallel to a bottom wall. 2. The silicone rubber foam precursor is foamed in a frame while the upper surface of the silicone rubber foam precursor is covered with urethane foam.
Item 6. A method of foam cutting a silicone rubber foam according to the item. 3. The method of foam cutting a silicone rubber foam according to claim 1, wherein the resin foam is urethane foam.