JPH05261820A - Method for bonding expandable synthetic resin member together - Google Patents

Abstract

PURPOSE:To reduce the fear for impairing the characteristics of stock material of respective expandable synthetic resin members by a method wherein expandable synthetic resin members including the bonding parts, which are heated up to fusible temperature, of surface layer cell walls are pressurized with each other to compressed state. CONSTITUTION:First and second expandable synthetic resin members 11 and 12 are prepared by slicing foam-molded resin stock material, which is prepared by foam-molding expandable synthetic resin material in advance and has elasticity restorable to expanded state, to the predetermined thickness and shaping to the desired planar shape so as to the surface layer cell portions 13a and 14a of respective planar exposed cell bonding faces 13 and 14 are fused and bonded together. For the fusing and bonding operation, a surface layer heating means arranged insertedly and separably between respective pressing faces 21a and 22a, which are opposite to each other and constituted pressingly and operably, of a pair of pressing molds 21 and 22 or, in this case, a temperature controlled plate-like surface heater 31 is employed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for joining foamable synthetic resin members to each other. The present invention relates to a joining method for fusion-bonding while maintaining a bubble state on a joining surface as much as possible.

[0002]

2. Description of the Related Art Generally, products made of a foamable synthetic resin material having resilience have been widely used for various purposes. As a convenient example, for example, in accordance with the outer shape of various articles to be stored in the container, hold the stored article in a desired storage posture,
Alternatively, there is a holder as a foamable synthetic resin molded article for packaging (hereinafter, also referred to as a foamable synthetic resin holder, or simply a holder), and this kind of holder is well known and widely used. There is.

In the usual case, for a molded product for holding a packaged article or using a foamable synthetic resin material having such a resilience, or for a package, a molding die including the outer shape of the packaged product is used. , Is formed by heat-foaming a foamable synthetic resin material in the mold. In heat foam molding using such a mold, in the case of heat molding using a mold made of a non-foamable synthetic resin material. Unlike the above, due to the type of expandable synthetic resin material and subtle changes in foaming conditions, there is an extreme difference in the foaming state, and it is not possible to mold a molded product of uniform composition with a given shape and size. As for itself, it is often different in part and effective surface restoration elasticity cannot be obtained. In addition, when coloring the whole product in a desired shade, the mixed pigment is partially biased. There is a disadvantage of such undesirable there also. Also in the heat foam molding using a molding die, for example, if the foaming is about twice as low, it is possible to mold without causing such a disadvantage, but the practical range itself is limited. It is desirable that the foaming is a multiple of more than that, and by the way, the foaming synthetic resin handled in the method of the present invention is supposed to have a foaming of about 15 times.

On the other hand, the above-mentioned expandable synthetic resin holder is used, for example, for holding or packaging the articles stored in the container, as described above. When it is necessary to match the internal shape and size with the external shape and size of the stored article as accurately as possible, and when forming a holder that requires such highly accurate shape and size. Was not suitable for the heat-foam molding using a general molding die as described above.

Therefore, conventionally, a material which has been foam-molded in advance by a foamable synthetic resin material having a resilience, that is, a foam-molded resin which has already been foamed by the normal foaming without the above disadvantages. A material (hereinafter also simply referred to as a foam-molding resin material) is sliced into a predetermined thickness dimension and used, and the foam-molding resin material is shaped and processed to form a substrate portion having a desired shape and size. After forming the foamable synthetic resin member and the second foamable synthetic resin member serving as the holding portion respectively, and then again joining the foamable synthetic resin members to each other, the holder is as intended. In this case, as a result, it is essential to join the foamable synthetic resin members having restoring elasticity.

[0006]

The means for joining the foaming synthetic resin members having the above-mentioned restoring elasticity to each other is as follows.
In the conventional case, the shapes and dimensions of the first and second foamable synthetic resin members are shaped to be slightly larger, and after combining them, the whole is pressed into a separately prepared molding die. , And then re-heat molding each foamable synthetic resin member and fusion-bonding each other, or after shaping each foamable synthetic resin member into a predetermined shape and size, Means such as adhesive bonding with an adhesive are taken.

However, in the former fusion bonding means,
Since the whole of the combined first and second expandable synthetic resin members is set in the mold and reheat-molded, the form of the closed cells or the continuous cells forming the foamed portion is easily collapsed, Not only the shape and dimensional accuracy after fusion bonding are not sufficient, but also a slightly hardened skin layer is formed on the surface portion that comes into direct contact with the mold surface, which hinders the restoration elasticity. In the latter adhesive joining means, the cost of manual pasting is relatively high, and the bubble portion is hardened by the penetration of the adhesive into the inside of the foam surface, which does not necessarily lead to a good adhesion mode, and the shape retention force is also weak, causing peeling. In addition, the solvent in the adhesive,
The characteristics of the material itself are impaired by the sulfur component and the like, and moreover, various problems such as not being suitable for bonding with an adhesive have occurred with olefin resins such as polysilicon ethylene and polysilicon propylene.

The present invention has been made in order to solve the above-mentioned conventional problems, and an object of the present invention is to prevent the characteristics of the material, particularly the foamed form, from being disturbed as much as possible. It is an object of the present invention to provide a method of joining foamable synthetic resin members to each other, which facilitates joining of foamable synthetic resin members to each other.

[0009]

In order to achieve the above object, a method of joining foamable synthetic resin members according to the present invention is a method of joining foamable synthetic resin members having restoring elasticity to each other. A heating step of heating the surface layer bubble wall joint portion of each of the foamable synthetic resin members to a fusing possible temperature, and pressurizing the foamable synthetic resin member including the heated surface layer bubble wall joint portion into a compressed state. A pressurizing step and a restoring step of releasing the pressurized and compressed state are included. In the pressurizing step, the cell wall portions heated to the fusible temperature of the foamable synthetic resin members are fused and suspended. It is characterized in that the foamed synthetic resin member is maintained in the foamed state by entwining and joining, and in the restoring step, the bubble wall portion other than the fusion-bonded portion is restored to a non-deformed state. To do.

[0010]

Therefore, according to the method of the present invention, after heating the surface layer cell wall joints of the respective foamable synthetic resin members to a temperature at which they can be fused, the foamable synthetic resin member containing the heated surface layer cell wall joints is formed. By pressurizing each other in a compressed state, the bubble wall portions can be fused and entangled with each other to be joined, and by releasing the compressed state, the bubble wall portions other than the fused portion are not deformed. 〝Can be restored to maintain the bubble state.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method for joining foamable synthetic resin members to each other according to the present invention will be described in detail with reference to FIGS.

FIGS. 1 and 2 are detailed sectional views schematically showing aspects of a heating step and a pressurizing step according to an embodiment method of the present invention, and FIG. It is a cross-sectional explanatory view schematically shown.

In the method of this embodiment, a foam-molded resin material which has been foam-molded in advance using a foamable synthetic resin material and has a restored elasticity is sliced into a predetermined thickness dimension and shaped into a desired plane shape. Using the first and second foamable synthetic resin members 11 and 12 that have been processed, the surface layer bubble wall portions 13a and 14a of the planarly exposed bubble bonding surfaces 13 and 14 are fused to each other. In this fusion-bonding operation, a pair of pressure pressing dies 21 and 22 configured to pressurize the pressure surfaces 21a and 22a facing each other and the pressure surfaces 21a and 21a, Surface layer surface heating means, which is arranged so as to be insertable and removable between 22a, is used as the surface heating heater 31 in the form of a plate whose temperature is controlled.

A specific fusion-bonding operation according to this embodiment will be described below.

First, the pair of pressure pressing dies 21 and 22
And the respective first and second foamable synthetic resin members 11 and 1 are opened at predetermined positions of the pressure surfaces 21a and 22a.
By setting and holding 2, the respective bubble bonding surfaces 11a and 12a are made to face each other with a predetermined interval.

Next, in the heating step, a temperature-controlled surface heating heater 31 as a surface layer surface heating means is inserted between the air bubble bonding surfaces 11a and 12a, which are the bonding surfaces (FIG. 1), and are opposed to each other. After heating the surface layer bubble wall portions 13a and 14a of the formed bubble bonding surfaces 13 and 14 to a required fusing possible temperature, the surface heating heater 31 is removed.

Then, in the pressurizing step, the pair of pressurizing and pressing dies 21 and 22 are closed, and the foamable synthetic resin members 11 and 12 set and held at predetermined positions are connected to each other, and by extension, the bubble bonding surfaces 11a. , 12a are brought into contact with each other and operated under pressure to compress and compress the respective foamable synthetic resin members 11 and 12 themselves (FIG. 2), so that each surface layer bubble heated to the fusing possible temperature. The wall portions 13a and 14a are joined to each other in a complicated state by fusion bonding and suspension.

After that, in the restoring step, the pressurizing and pressing states of the pressurizing and pressing dies 21 and 22 are released and opened again, so that the foamable synthetic resin members 11 and 12 are restored to their original state by their elasticity. The state is restored, and at the same time, the surface layer bubble wall portions 13a and 14a other than the fusion-bonded portion are restored to the non-deformed state.

Therefore, in the method of the above-mentioned embodiment, since the heated surface layer cell wall portions of each expandable synthetic resin member are fused and entangled with each other, strong joining can be performed very easily. At the same time, the bubble wall parts other than the fusion-bonded part can be restored to the non-deformed state, and there is little fear that the foaming form of each part including the joint part will be destroyed, and each foamable synthetic resin after joining The bubble state of the member can be maintained well.

In the method of the above embodiment, the case where each of the expandable synthetic resin members to be joined has a flat plate shape has been described, but the invention is not limited to the flat plate shape, and the surface cell wall can be fused. It may have any shape as long as it can be heated to a temperature. Further, although the case where the plate-shaped surface heater is used as the surface layer surface heating means has been described, it goes without saying that a means for moving the rod-shaped heater, a hot air heating means, or the like can also be adopted.

[0021]

As described above in detail with reference to the embodiments, according to the method of the present invention, in the method of joining the expandable synthetic resin members having the restoring elasticity to each other, the surface layer bubbles of the expandable synthetic resin members are joined together. After heating the wall joints to a temperature at which they can be fused, the foamable synthetic resin members including the heated surface cell wall joints are pressed into a compressed state to fuse and suspend the cell walls. It can be easily joined by entanglement, and by releasing the compressed state, the bubble wall part other than the fusion part can be restored to the non-deformed state, effectively maintaining the bubble state of each foamable synthetic resin member. Fusion bonding is also possible, and regarding the joining form, because of the fusion between the surface layer bubble wall joints and the suspension, the joining is strong and there is no hardened portion on the joint surface. As a result, it does not occur May excellent features such as small a danger of damaging the material characteristics of the expandable synthetic resin member itself.

[Brief description of drawings]

FIG. 1 is a detailed sectional view schematically showing an aspect of a heating step in a method for joining foamable synthetic resin members to each other to which an embodiment of the present invention is applied.

FIG. 2 is a detailed cross-sectional view schematically showing an aspect of a pressing step in the above joining method.

FIG. 3 is a cross sectional explanatory view conceptually showing one example of the above-mentioned joining mode.

[Explanation of symbols]

 11, 12 First and second foamable synthetic resin members 13, 14 Bubble joining surface 13a, 14a Surface layer bubble wall portion 21, 22 Pressing type (pressurizing means) 21a, 22a Pressing surface 31 Surface heating heater (table Layer surface heating means)

Claims (2)

[Claims] 1. A method of joining foamable synthetic resin members having restoring elasticity to each other, comprising a heating step of heating a surface layer cell wall joint portion of each of the foamable synthetic resin members to a fusing possible temperature, The method includes a pressurizing step of pressurizing the foamable synthetic resin members including the heated surface layer cell wall joints into a compressed state, and a restoring step of releasing the pressurized and compressed state. Of the flexible synthetic resin member, which are heated to a temperature at which they can be fused, are fused and entangled with each other, and in the restoration step, the bubble wall portion other than the fused portion is restored to a non-deformed state. The method of joining foamable synthetic resin members to each other is characterized in that the foamed synthetic resin members can be maintained in a bubble state. 2. A set of pressure pressing dies, which are configured to be capable of pressurizing the respective pressure surfaces facing each other, are provided, and the bubble bonding surfaces of the foamable synthetic resin members are provided on the respective pressure surfaces. The surface layer heating means is inserted and removed between the respective bubble bonding surfaces to be held facing each other and bonded to each other, and when the surface layer heating means is inserted, the surface layer bubble wall of each bubble bonding surface. The method for joining foamable synthetic resin members to each other according to claim 1, wherein the joining portion is heated to a temperature at which fusion can be performed, and when the joining portion is detached, the pressurizing and releasing operations of the respective pressing dies can be performed.