JPS61219634A - Sealed type thermal expandable flat body - 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 (a) Industrial Application Field The present invention relates to a sealed heat generating material for forming a foam used for sealing, heat insulation, sound absorption, vibration damping, etc. in home appliances, automobiles, houses, etc. This invention relates to a foamable flat body.

(1) Prior Art Foams have been used in various industries since they exhibit good properties such as heat insulation, sound absorption, and vibration damping. However, when assembling the foam as part of a structure, it is bulky and difficult to handle, especially when the foam is attached to a specific location on an already assembled structure. The drawback is that it is difficult to install and has poor workability, such as having to insert it in a certain condition.

In order to solve the above-mentioned drawbacks, the following methods have been proposed.

The first method is related to two-wave foamable resin, in which a foaming agent component and a resin component are mixed at the time of use, the mixture is injected into an insulated area of a structure, and then heated and foamed to form a foam. is formed.

The second method relates to a two-cell resin sheet,
An unfoamed resin sheet mixed with a foaming agent is pasted on the above-mentioned specific location of the structure, and after f=1 digit, it is heated and foamed to form a foam.

(c) Problems that Aimei tries to solve However, in the first method, since the foaming resin is in liquid form, the resin is injected into unnecessary areas, and as a result, it is difficult to locate specific parts of the groove relic. It was not possible to form a shaped foam.

In addition, in the second method, since an unfoamed foaming agent is mixed into the unfoamed resin composition, blurring occurs during heating and foaming, and as a result, the degree of foaming varies depending on the heating temperature.
It was difficult to form a foam with good dimensional stability, and it was extremely difficult to handle. Therefore, the present inventor added a heat-melting or heat-softening adhesive to a foam and flattened it by heating and pressurizing the foam to create a heat-foamable flattened product (hereinafter referred to as a heat-foamable flat body). proposed (patent application 1986-648)
No. 33, filed on March 30, 1982).

However, the matrix of this thermally foamable flat body is Ji! Since the foam is of an open-cell type or has some open-cell portions, liquid substances such as water and oil can penetrate through the cell passages, making it impossible to achieve sufficient sealing performance. Therefore, when the above-mentioned flat body is used in a location where the sealing performance is poor, for example, a location where liquid substances such as water and oil flow in, the inflow of water causes various problems such as rust and RF.

For this reason, in the home appliance/automotive field, housing field, etc.
ζ, honey j! A foam material immersed in gender was strongly requested.

(d) Means for Solving the Problems The inventor of the present invention, as a result of repeating the sharp M and +2 revisions for the purpose of solving the above-mentioned drawbacks, found that at least the liquid material inlet side of the outer peripheral part of the above-mentioned heat-foamable flat body. It was discovered that a covering material having sealing properties can be provided on the wall surface portion, leading to the present invention.

That is, the present invention provides a heat-foamable flat body in which an elastic foam containing a fixing agent in the void is flattened and this flattened state is maintained by the fixing agent. It is characterized by having a small wall area (in both cases, a coating material is provided on the wall surface portion on the liquid material inflow side).

The elastic foam used in the present invention refers to the elastic foam that returns to its original state when the external force is removed when the foam itself is compressed and deformed by an external force, regardless of whether or not the polymer material itself that forms the foam has elasticity. It is fine as long as the condition can be recovered.

As for the foaming state of the above elastic foam, an open cell type is preferable because it allows the adhesion agent to be contained in the voids and is easy to flatten, but the adhesion agent must be included to the extent that the flattened state can be maintained. If possible, the apparent density of the foam, which may have some closed cells, is usually 0.5 or less, with a lower limit of about 0.005 and a more preferable range of 0. It is .02-0.3.

If this apparent density is too high, even if the foam is flattened, the volume will only decrease slightly, and since there are few voids, it will not be possible to contain the necessary amount of adhesive to maintain the flattened state. If it is too low, the above-mentioned foam will have poor rock-solid properties, which is undesirable.

Furthermore, the number (7) of the elastic foam is usually preferably 11 or more, and more generally a practical range of about 3 to 100 mm, but it is not limited to this.

The above-mentioned elastic foam can be manufactured by various known methods using various polymers. The polymer to be used is not particularly limited as long as it can form a foam having the above-mentioned tfiD, and examples include polyethylene, polypropylene, ethylene-vinyl acetate, polyurethane, and rubber. can.

The fixing agent used in the present invention is a resin that softens or melts when heated and can solidify when cooled. This adhesive needs to have a melting point or softening point lower than that of the foam. If the melting point or softening point of this adhesive is higher than the melting point or softening point of the above-mentioned foam, when the foam is flattened and fixed with the adhesive to maintain this flattened state, the flattened When the foam is heated to remove the adhesive force of the adhesive, the cells in the foam collapse, and even if the adhesive force is removed, the foam does not return to its original state, making it impossible to achieve the object of the present invention.

Further, the melting point or softening point of the above-mentioned fixing agent is generally 10°C or more higher than room temperature, and the more preferable melting point or softening point is 30 to 180°C. If this melting point or softening point is too low, it is undesirable because it will restore to the vBH type thermally exothermic foamable flat foam state during storage, and if it is too high, it is generally This is undesirable because it causes deterioration and, as a result, the properties of the restored foam deteriorate.

Various resins can be used as the fixing agent as long as they have the melting point or softening point as described above, but among these, resins with a narrow melting point range and low molecular weight are the ones whose viscosity decreases rapidly when heated. This is preferable because the flat body can be quickly restored. Examples of resins that can be used as this adhesive include epoxy? Examples include thermosetting resins such as A (Wl, 7-el resin, polyester U (fat), and thermoplastic resins such as polyethylene, polypropylene, polyamide, and polybutyral. In addition, these resins can be used to adjust the viscosity when melted. Various additives such as plasticizers and fillers may also be added to reduce costs.

Alternatively, a thermosetting resin with a curing agent that reacts when heated may be used as the adhesive, and the adhesive may be cured after the flat body is restored to its original foam form by heating. good. According to this, the hardness and strength of the restored foam can be adjusted. However, as the above-mentioned curing agent, the curing agent does not proceed at the heating temperature used to make the foam into a flat body, and the curing agent cures the resin at a temperature that does not affect the foam shape of the restored foam. Needless to say, use it.

Examples of this type of curing agent include various amine-based curing agents, imiguzol-based curing agents, nocyanonamide, acid anhydride-based curing agents, and polyester-based curing agents for epoxy resins.
Examples of 117 include peroxide compounds.

This [l! In order to incorporate the adhesive into the voids of the elastic foam, the adhesive is dissolved in a solvent to form a solution, the foam is impregnated with this solution, and then the solvent is removed, or the adhesive is in the form of a powder. There are methods such as rubbing the foam into the foam or vibrating the foam to incorporate the adhesive, or immersing the foam into a molten adhesive.

The amount of adhesive to fill the voids in the elastic foam is as follows:
Usually, the amount of adhesive is 2 in the total amount of elastic foam and adhesive.
The amount is preferably about 0 to 85% by weight, and is appropriately determined based on the relationship between the elastic recovery force of the foam and the fixing force of the adhesive so that the flattened state of the foam can be maintained by the fixing force. For example, apparent density 0.02, thickness 110lll1
Usually 100-800g for polyurethane foam books.
/m2.

As described above, the thermally foamable flat body used in the present invention can be obtained by flattening the elastic foam containing the adhesive in the voids and maintaining this flattened state with the adhesive.

To perform the above flattening, the foam containing the fixing agent is heated to a temperature at which the fixing agent softens or melts to the extent that it can be fixed. solidify. The above-mentioned temperature does not necessarily have to be higher than the melting point of the fixing agent as long as it can be fixed, and it needs to be a temperature at which the foam does not soften or melt. A specific method for this flattening is, for example, a method in which a foam containing a fixing agent is heated and pressurized in a hot press heated to around the melting point of the fixing agent to flatten it, and then cooled in this flattened state ( In this case, depending on the temperature of the hot press, a cooling step may not be necessary and it may be sufficient to just take it out from the press.), or a method in which the sheet is flattened using cooling rolls immediately after heating.

The thickness of the flat body obtained in this manner is usually about 1/15 to 1/2 of the thickness of the original foam.

The most significant feature of the present invention is that in the outer peripheral part of the heat-foamable flat body formed as described above, there is no inflow of liquid such as water or oil into the wall surface on the demon side. The reason is that a 17IvL covering material is provided to stop the problem.

That is, a major feature of the present invention is that a sealing material is provided on the entire outer periphery of the heat-foamable flat body or on the wall surface of the outer periphery on the side into which liquid substances such as water and oil flow. There is.

As the above-mentioned covering material, various films such as polyethylene, polyethylene terephthalate, polypropylene,
Films such as polyvinyl chloride, polyamide films, and polyester films can be used alone or in combination, and as paint types, various synthetic resins such as vinyl acetate and vinyl acetate-acrylic can be used. There are acid ester copolymer systems, vinyl acetate-vinyl chloride copolymer systems, and acrylic ester copolymer systems, and synthetic rubber latex and the like can also be used.

In order to cover the outer periphery of the heat-foamable flat body with the coating material, the film is stretched or coated or impregnated with the paint at necessary locations on the outer periphery.

The covering material softens or melts when heated, and the flat body expands as the flat body expands, which hinders the restoration of the flat body.

Next, an example of the manufacturing process of the sealed thermally foamable flat body of the present invention will be explained with reference to the drawings.

(a) First, fill the voids of the elastic foam (1a) with the adhesive (2
) by impregnation or rubbing (see Figure 1(a)).
), (b) Next, this is heated to soften or melt the above-mentioned fixing agent and pressurized to flatten it, and the above-mentioned fixing agent (2) is solidified by cooling it in this flattened state. A thermally foamable flat body (11) is obtained (r:tS
Figure 1 (b)).

(c) Finally, a covering material (3) is provided on a portion of the outer periphery of the flat body (1b) by the above-mentioned method.

In this case, the flat body (1b) may be enclosed in a heat-sealable film bag (3'), as shown in Figure 2 (,) and Figure 2 (1+). It is preferable that the internal volume of the film bag (3') is smaller than the volume of the flat body (1b) when it is foamed, so that an outward pressure is applied to the bag (3') to increase the gi. This makes it possible to realize a sealing function.

By going through each of the above steps, the desired sealed heat-foamable flat body (1) can be obtained.

Note that the sealed heat-foamable flat body obtained in this way may be provided with an adhesive layer on one or both sides, and thereby,
It is also possible to improve the workability when attaching the flat body to the body to be mounted.

Specific applications of the sealed heat-foamable flat body of the present invention include use for reinforcing, sealing, and insulating spaces in various structural members such as automobile bodies, or for use in rotating motors, etc. It can also be used to prevent noise at parts of the body where vibrational sounds are generated. Moreover, since the flat body has sealing properties even after foaming and restoring, it can be effectively used even at locations where water, oil, etc. enter.

Next, an example of how the sealed thermally foamable flat body (1) is used will be explained with reference to a drawing. As shown in Fig. f53 (a), the flat body (1) is inserted between the objects to be attached (404). When the flat body (1) is heated to a softening point or melting point of the fixing agent (2) containing the flat body (1) at a predetermined location, the flat body (1) foams and restores its shape. As a result, a foamed body (5) is formed between the attached bodies (4) (4).

In the case of foam, as shown in Figure 4 (, ) and Figure 4 (b), the coating material (3) softens due to heating, and as the flat body (1) foams. Since it is stretched, there is no problem in restoring the flat body (1).

As mentioned above, when the entire outer periphery of the flat body (1) is coated with the coating material (3), a remarkable sealing function against liquids such as water and oil is realized. Mounted body (
4) A foam (5) can be interposed between (4).

(e) Effect Since the sealed heat-foamable flat body of the present invention is formed by holding an elastic foam in a flat shape with a heat-melting or heat-softening adhesive, the adhesive can be removed by heating. By melting or softening, the flat body can be restored very easily and with good dimensional stability.

Furthermore, since the sealed heat-foamable flat body is provided with a covering material on at least the wall surface portion of the outer periphery where sealability is required,
After the above-mentioned flat body is attached between the objects to be attached and restored, liquid substances such as water and oil will not flow into the inside from the attachment point.

(f) Examples Example 1 10+n+ consisting of ethylene-vinyl acetate copolymer.

Thick foam (apparent density 081, open cell type, melting point 10
0 to 120°C) was impregnated with a 10% acetone solution of an epoxy resin (trade name: Epicor #1001, manufactured by Yuka Nel Co., Ltd., melting point: 64 to 74°C), and then 7 setones were removed. As a result, the above-mentioned foam was impregnated with 150 g/2 epoxy resin.Then, this foam was flattened using a hot press at 50°C to obtain a heat-foamable flat body having a thickness of 1.2I6111.

Next, a polyester film (30μ) whose inner surface was coated with polyethylene 1! ! The entire outer periphery of the flat body was covered by enclosing the flat body in a bag. At this time, the inner volume of the bag was made to be 60% of the original foam, and the bag was configured so that an outward pressure would be applied to the bag when it was restored by heating and foaming.

This sealed thermally foamable flat body was placed between the objects to be attached with a gap of 51 nlI, and when heated in a dryer at 70°C, it foamed and restored after 2 minutes, and the gap between the objects to be attached was Filled the gap. This product also had sealing properties against moisture.

Example 2 While vibrating a 5 mm thick urethane foam (apparent density 0.02, open cell type, melting point 340°C), polyamide powder (manufactured by Romotosu Roussin Co., Ltd.) of 60 mm thick was applied to the entire void space of the foam. Name Buratamide H-103, melting point 80
~90°C) in an amount of 80g/2 spears, the foam was heated to 150°C, and immediately thereafter flattened through cooling rolls to obtain a heat-foamable flat body with a thickness of 0°81.

Next, Emaruno a, a vinyl acetate copolymer, was applied to the entire outer periphery to form a 'ζ film, thereby obtaining a sealed heat-foamable flat body of the present invention. This one has a gap of 31 F
When placed between 7+ wave wearing bodies and heated to 150℃, 1
After a few minutes, it foamed and restored, filling the gap. This product had sealability against moisture.

In each of the above embodiments, the coating material was formed on the entire outer circumference of the flat body, but instead of this, the fourth embodiment was explained.
As shown in FIG. 4(a) and FIG. 4(b), the tW material may be provided only on the wall portion of the outer periphery where sealing performance is required.

(g) Effects of the Invention Since the present invention is configured as described above, it is not bulky and can be handled very easily during transportation and installation in gaps, and moreover, the installation requires no heating afterward. This allows the gap to be easily filled with the foam.

In particular, since the sealed heat-foamable flat body of the present invention has a coating material on at least the wall surface on the liquid inflow side of its outer periphery, it is possible to reliably prevent the inflow of liquids such as water and oil. , it can be effectively used even in locations where the above-mentioned liquid material flows.

[Brief explanation of drawings]

1(a) to 1(c) are partial cross-sectional views illustrating the IJl manufacturing method of the sealed heat-foamable flat body of the present invention, and FIG.
a) and FIG. 2(b) are partial sectional views showing the case where a film bag is used as the covering material, and FIG. 3(a) and FIG. 3(b) are the sealed heat-foamable flat bodies of the present invention. FIGS. 4(a) and 4(b) are sectional views showing other embodiments of the sealed thermally foamable flat body of the present invention. 1... Density 11 type heat-foamable flat body 1a... Amane foam book lb... Heat-foamable flat body 2... Adhesive agent 3... Covering material 3'... Film bag making 1 cover material) 1... 嘗 り 翿 8社 fake body 1 b... heat S so history denpei stop 2... (11 wearing system 3... double Jaku size 4 figure 4 ( b)

Claims (1)

[Claims] (1) In a heat-foamable flat body formed by flattening an elastic foam containing a fixing agent in the void and maintaining this flattened state by the fixing agent, the flat body has at least a liquid material on its outer periphery. A sealed thermally foamable flat body characterized by providing a covering material on the wall surface on the inflow side.