KR100627145B1 - Manufacturing process of continuous foam which having inner cavity - Google Patents

Abstract

The present invention relates to a method for producing a continuous foam having an internal cavity structure using the advantages of atmospheric pressure and pressure simultaneously, comprising the steps of processing a continuous molding material in the longitudinal direction as crosslinked foam is suppressed; Preparing two or more processed molding materials to form an interface having an arbitrary shape using one or more boundary materials to prevent physical and chemical bonding between the molding materials on one or more of the molding materials; Injecting a molding material having the interface between the metal plate belts of the continuous pressurizing and crosslinking unit including a pair of plate plate belts and heating means for endless track motion, and using heat continuously transferred through the metal plate belts. With the sheet belt between the sheet belt Continuously press-crosslinking the moving continuous molding material, and continuously foaming the molding material continuously exiting the metal sheet belt in a crosslinked state, thereby implementing a foam having a hollow structure having an arbitrary shape therein. Its technical features, including what is done.

Molding material, boundary material, interface, internal cavity structure, foaming, pressurization, continuous

Description

Manufacturing process of continuous foam which having inner cavity

1 is a process diagram of a continuous foam manufacturing method provided with an internal cavity structure according to the present invention.

2 is a schematic configuration diagram of a continuous pressure crosslinking unit according to the present invention.

3A is a schematic configuration diagram of a molding material in which an interface of arbitrary shape is formed according to the present invention;

Figure 3b is a block diagram showing the step of the step of feeding the continuous pressure cross-linking portion of the molding material formed the interface in accordance with the present invention.

Figure 3c is a block diagram showing a continuous pressure crosslinking step of the molding material formed interface according to the present invention.

Figure 3d is a block diagram showing the step of forming a cavity structure therein while continuously forming a foaming material formed with an interface according to the present invention.

4A is a perspective view of a continuous foam with an internal cavity structure implemented in accordance with one embodiment of the present invention.

4B is a cross-sectional view taken along the line A-A 'of FIG. 4A;

The present invention relates to a foaming method of a molding material, and more particularly, by continuously pressurizing and cross-linking a continuous molding material having a boundary surface formed and then continuously foaming it to produce a continuous foam having an internal cavity structure in a pressurized manner. It is about how it can be.

Foaming of the molding material is to use the mechanical equipment selected by taking into account the shape and physical properties of the foam to be implemented, usually pressurized directly to the molding material processed into a constant shape, such as pellets (sheets) Depending on whether the foam is formed by heating, it can be classified into pressurized and atmospheric pressure.

The pressurization type forms a foam material by placing the molding material inside the mold, and then heats and pressurizes it to an appropriate condition. The final foam shape can be freely changed by the internal cavity shape of the mold in which the molding material is placed. In addition, since the molding material undergoes a crosslinking process in a state of directly contacting the inner cavity of the mold, the surface of the final foam that is realized is uniformly formed, and thus is widely used in various applications.

However, the pressurization type requires a mold having internal cavities identical to a specific shape of the final foam in order to implement the foam, even if the shape of the final foam is the same. There is a problem that increases the exponential price of the product increases exponentially.

In addition, the pressurization type implements a foam through a series of processes, such as opening a mold, placing a molding material, closing a mold, heating a mold, and opening a mold. In this case, a foam is manufactured through a process of opening and closing a mold. There was a limit in productivity because the production of the product had to be made discontinuously.

Moreover, in order to increase the size of the final foam to be implemented, it is necessary to increase the size of the press itself, which is a means for pressurizing a mold. In general, considering the huge weight of the press, this also has a limitation, which can be manufactured under pressure. The size of the product was limited.

On the other hand, the atmospheric pressure type, unlike the pressurization type, does not use a mold having an internal cavity having a specific shape as a pressurizing means in the process of heating the molding material, so that the foam can be continuously formed, and the size of the final foam can be arbitrarily increased. The advantage is that you can.

However, since there is no pressurizing means for controlling the volume of the molding material foamed in the foaming step, the surface of the final foam to be realized is less uniform than the foam realized by the pressurized type, which means that the surface of the foam is somewhat roughened. It means that the process to be uniformly added has a disadvantage in that the production efficiency is lower than the pressure type.

In addition, the atmospheric pressure is foamed through the crosslinking process in the open state of the molding material, so that the entire molding material may undergo a uniform crosslinking process, unlike the pressurized foam which is foamed after the uniform crosslinking process is completed in the sealed inside of the mold. There was also a disadvantage that the physical properties of the foam, such as the tensile strength and compressive strength of the final foam that is implemented without a means of forcing it can not be applied to various products.

In addition, there is no way to implement a continuous foam having a cavity structure formed in any shape therein by the atmospheric pressure type widely used in the art.

The present invention has been devised to solve the above problems, and an object thereof is to provide a manufacturing method which can continuously implement a foam having a cavity structure formed in an arbitrary shape by a pressure method.

Another object of the present invention is to provide a manufacturing method capable of freely adjusting the size of the continuous foam to be implemented and the shape of the internal cavity formed inside the foam.

In order to achieve the above object, the present invention provides a method for producing a continuous foam, comprising the steps of processing a continuous molding material in the longitudinal direction as cross-linked foam is suppressed, and preparing two or more processed molding materials and then prepared molding Forming an interface having an arbitrary shape using at least one boundary material on the surface of at least one of the molding materials to prevent physical and chemical bonding between the molding materials, and in opposing directions, spaced apart at regular intervals and facing each other. And a pair of metal plate belts acting as a pressurizing means for suppressing the foaming of the molding material and heating means for continuously supplying heat to at least one selected from the metal plate belts. The interface between the metal plate belt is mold Injecting the formed molding material, and continuously press-crosslinking the continuous molding material moving together with the metal plate belt between the metal plate belts by using heat continuously transmitted through the metal plate belts. It is characterized in that it comprises a step of forming a foam having a hollow structure having an arbitrary shape inside by the interface by continuously foaming the molding material continuously exiting the metal plate belt in the state.

In the interface forming step, the boundary material is characterized in that it is made of any one or more selected from a liquid or solid material, or a molding having a predetermined shape.

After the continuous foaming step, the step of injecting or inserting at least one selected from a gas, a liquid or a solid material, or a molding having a predetermined shape into the inner cavity of the continuous foam is further added. do.

The continuous pressure cross-linking unit is characterized in that the vertical height adjustment means for adjusting the interval between the metal plate belt in response to the molding material is formed in the interface is further provided.

The continuous pressurizing cross-section is characterized in that it is further provided with a pressing means for pressing at least one of the metal plate belt in order to suppress the foaming of the crosslinked molding material while moving with the metal plate belt.

The continuous molding material is characterized in that the thin film form.

Preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. The present invention provides a processing step (S100), an interface forming step (S200) of a molding material, and a molding material input to a continuous pressure crosslinking unit. It comprises a step (S300), a continuous pressure crosslinking step (S400) of the molding material, and a continuous foaming step (S500) of the crosslinked molding material.

The processing step (S100) of the molding material is to prepare the raw material for the molding material using the main resin material selected from a variety of materials according to the use and physical properties of the foam to be implemented, and then the main resin according to the material mix design criteria When the compound is formed through a compounding step using a suitable equipment by weighing materials and sub-materials by a certain weight value, the compound is processed into a molding material in which crosslinked foaming is suppressed through a calender or an extruder. .

The molding material preferably uses various synthetic resins such as ethylene vinyl acetate (EVA) based on various vinyl acetate contents (VA%) or polyethylene (PE) based on various densities as main raw materials. The present invention is not limited thereto and may be arbitrarily selected from materials that can be made into a molded body by various crosslinked foam molding methods such as various natural rubbers or synthetic rubbers, synthetic resins and composite materials of rubber.

Molding material according to the present invention is not limited to the shape as long as it is made of a continuous shape in the longitudinal direction, but the surface state is preferably made of a uniform planar shape, the surface roughness degree (or thickness variation is constant It is more preferable that)) consists of a film of precise thin film form.

Therefore, when the surface roughness degree of the processed molding material is formed into a somewhat rough sheet shape, it may be desirable to use the same after reprocessing the material to realize a precise thin film shape.

The interface forming step (S200) is a state in which crosslinked foam is suppressed, and prepares two or more molding materials processed into a length shape, and then uses an interface material on any one or more selected surfaces of the prepared molding materials to form an interface having an arbitrary shape. Forming step.

The boundary material is to prevent physical and chemical bonding between the molding materials that are in contact with each other in the continuous pressurization step of the molding material to be described later, the boundary material is a liquid having a constant viscosity, or a powder of a predetermined size. Or as long as it is possible to prevent the bonding of the molding materials in the pressure crosslinking process, such as a solid formed in a certain shape, such as a molded article or a film, there is no limitation to the material and shape.

The method of forming the interface is not limited to printing, transfer, coating, lamination, spraying, lamination, insertion, attachment or deformation thereof, or a method in which the boundary material can be formed on the surface of the molding material. The shape of the interface is also completely arbitrary and is not particularly limited.

In addition, in the case where two or more boundary surfaces are formed, all of the interface surfaces may be formed as the same boundary material, or each boundary surface may be formed using different boundary materials. Any one or more of different kinds of blowing agents may be selected and added to the material forming the interface.

3A is an example in which a boundary surface is formed on a molding material according to the present invention. After preparing two molding materials 10 processed in the longitudinal direction, the boundary surface 120 having an arbitrary shape on the surface of any one of the selected molding materials is prepared. It is shown that the case of forming the following manufacturing process will be described based on this.

After processing the continuous molding material in the longitudinal direction as cross-linked foam is suppressed, and then forming the interface on any one or more surfaces selected from the processed molding material, as shown in Figure 3b to continuously crosslink Injecting the molding material 10 into the continuous pressurizing crosslinking unit (S300), the step of continuously crosslinking the pressurization (S400) is continued.

One preferred configuration of the continuous pressure crosslinking unit according to the present invention is shown in Figure 2, the continuous pressure crosslinking unit 200 is a pair of metal plate belt 220 in the orbital motion in the opposite direction in a state spaced apart at regular intervals from each other, 270, and a heating means 290 for continuously supplying heat to each of the metal plate belt.

The heating means 290 is a means for crosslinking the molding material 10 by continuously supplying heat to the molding material 10 introduced into the continuous pressure crosslinking unit 200, and appropriately heats the metal plate belts 220 and 270. The present invention is not limited to heating means having any particular configuration because it is sufficient to supply crosslinking to form a crosslinked molding material moving together with the metal sheet belt between the metal sheet belts.

The metal plate belts 220 and 270 are means for moving the continuous molding materials introduced, and are means for crosslinking the molding materials by appropriately transferring the heat supplied from the heating means 290 to the moving molding materials. At the same time as a means for suppressing the foaming of the molding material crosslinked by the use of a tension.

The metal plate belts 220 and 270 are not particularly limited in thickness if only appropriate tension is ensured, and the width of the metal belts 220 and 270 may be appropriately changed depending on the size of the injection molding material, but is not limited to a specific value. It is preferred to be formed wider than the width of the material.

Meanwhile, the metal plate belts 220 and 270 are preferably driven by the upper rollers 212 and 214 and the lower rollers 262 and 264 which rotate in opposite directions as shown in the art, which is widely known in the art. Detailed description thereof will be omitted.

On the other hand, the thickness and the number of the injection molding material is not particularly limited, and the present invention does not exclude a case where a plurality of molding materials having a constant thickness is added at the same time in this case, the continuous pressure crosslinking unit according to the present invention is opposed to each other It is preferable that the vertical height adjusting means 230 and 240 which can properly adjust the interval of the metal plate belts 220 and 270 to be further provided.

In addition, the present invention, in addition to the metal plate belts 220 and 270 functioning as a means of preventing the molding material from foaming in the crosslinking process, the external tension is maintained by the character of the metal plate belts 220 and 270 itself. As a means for reinforcing in the metal sheet belts 220, 270 is not excluded when the case is further provided with a means for pressing any one or more belts selected from, the metal plate belt 220, 270 in this configuration An example assuming a case where the pressurizing means 280 is added to is disclosed.

In the case where the pressing means 280 is further provided according to the present invention, the pressing means 280 is in contact with the metal plate belts 220 and 270 as much as possible so that the foaming of the molding material to which the metal plate belts 220 and 270 are crosslinked. It is preferable to configure to control the phenomenon effectively.

Although the configuration of the pressing means 280 is not particularly limited, it is preferable that the pressing means 280 is formed in a flat plate shape having a predetermined thickness so as to press the metal plate belts 220 and 270 uniformly. In view of the heat transfer it will be preferable that the heating means 290 is installed inside the pressurizing means 280 as shown.

The continuous pressure crosslinking step (S400) is, as disclosed in Figure 3c, the continuous molding material 30 is formed with a continuous interface material 120 is formed between the metal plate belt 220, 270 of the continuous pressure crosslinking unit 200 is the metal plate In the process of moving together with the belt (220, 270) is a step of continuously receiving heat from the heating means 290 is crosslinked continuously.

That is, the molding material 30 moves in a state in which it is confined in a predetermined space between the metal plate belts 220 and 270 according to the movement of the metal plate belts 220 and 270, and continues from the heating means 290 during the moving process. The entire molding material 30 is crosslinked in a uniform state by the heat (ΔQ) transmitted to the foaming material, and the foaming phenomenon of the molding material 30 continuously crosslinking is caused by tension (and addition) of the metal plate belts 220 and 270. It is to be suppressed by the pressure (ΔP) continuously applied by the pressing means).

Meanwhile, in the molding materials 30 crosslinked while moving together with the metal plate belts 220 and 270, the continuous crosslinking occurs not only on the molding materials themselves but also on surfaces where the molding materials are in contact with each other, but the boundary surface formed through the boundary material. The crosslinking phenomenon between the molding materials is disturbed by the boundary material at the portions of the molding material contacted to both sides based on the reference numeral 120.

Therefore, in the continuous pressure crosslinking step (S400), except for the portion of the boundary surface 120 where crosslinking is hindered, the molding material 10 processed and input separately is as shown by reference numeral 30 → 50 during the continuous crosslinking process. There is no distinction between the molding materials and the same process as crosslinking a single molding material.

3c illustrates a case in which a pressing means is added to continuously pressurize the metal plate belt in order to more appropriately suppress the foaming phenomenon of the molding material. In the present invention, unlike the present invention, the molding is crosslinked using only the tension of the metal plate belt itself. Of course, the material can be pressurized.

The molding material continuously crosslinked between the metal plate belts 220 and 270 in which a constant pressurized state is maintained is continuously foamed as shown in FIG. 3D as it is naturally exposed to the external environment while leaving the metal plate belts 220 and 270. In step S500, the molding materials 50 sequentially leaving the metal plate belt, which is kept under a constant pressure state, are naturally continuous as shown in FIG. 3D in the order of leaving the metal plate belt as the pressure state is released at a time. The foam 70 is implemented.

On the other hand, when the foam is formed, the parts of the molding material which are not bonded to each other due to the interface formed on a predetermined portion inside the molding material until the foaming step are expanded and foamed in the same proportion as other parts on the foam during foaming, As the molding materials are foamed in a state separated from each other by the boundary material, a three-dimensional space having a predetermined shape is formed inside the foam, and the space formed inside the foam is the internal cavity structure 160.

Figure 4a shows a configuration of a continuous foam that can be implemented according to the manufacturing process of the present invention described above, Figure 4b shows a cross-sectional view A-A 'of Figure 4a.

The internal cavity structure 160 formed by the inner molding surface 162 has a predetermined amount of gas (eg N ₂ , CO _2, etc.) that is not discharged to the outside of the foam in the gas generated by the decomposition action of the foaming agent during foaming. As the cavity structure 160 is filled, the internal space maintains a constant air pressure.

The shape and structure of the internal hollow structure is completely irrelevant to the structure and shape of various manufacturing tools or equipment related to the foam molding, such as a mold, the present invention variously changes the shape of the interface between the shape and the structure of the internal hollow structure Or by varying the boundary material constituting the interface.

On the other hand, since the foam formed through the continuous foaming step is naturally foamed in the external environment, its surface may be formed to be rather rough rather than uniform, and the present invention may be performed by adding a continuous molding step to planarize the surface of the continuously formed foam. The case where a molded foam is obtained is not excluded.

The continuous molding step, it is preferable to use a forming roller consisting of a pair of rollers that are spaced apart at regular intervals well known in the art to rotate in the opposite direction, the forming roller in consideration of the thickness of the foam and the continuous pressure cross-linking unit It is more preferable that roller interval adjusting means capable of adjusting a pair of roller intervals facing each other is provided.

In addition, the present invention is a gas containing air, or a liquid substance having a constant viscosity, or a powder and a certain shape in any one or more of the internal cavity of the foam implemented through the continuous foaming step or all of the internal cavity It may further include the step (S700) of injecting or inserting any one or more selected from a solid material consisting of, of course, the molded material is included in the solid material of a predetermined shape.

It is apparent that material injection or insertion into the inner cavity is possible at any time after the continuous foaming step in which the inner cavity is formed.

In the above, the present invention is limited to the preferred embodiments of the present invention. However, the present invention is not limited thereto, and various changes or modifications can be made, and such changes or modifications fall within the scope of the present invention as long as the changes or modifications are made to those skilled in the art. something to do.

The present invention is to configure the crosslinking process of the molding material to be made in a constant pressure state by using the tension of the metal plate belt rather than a mold having an internal cavity of a specific shape, it is possible to realize a relatively large and continuous foam of the size In this respect, it helps to overcome the limitations of pressurization.

In addition, the present invention is configured to be uniformly cross-linked except the interface by receiving heat continuously from the heating means in a state in which the molding material is constantly pressurized by the metal plate belt, the excellent excellent continuous foam implemented At the same time, it provides the advantages of overcoming the limitations of atmospheric pressure in that it can have physical properties.

In addition, the present invention has a unique effect that can control a variety of shapes and physical properties of the hollow structure formed therein so that the continuous foam can be actively applied to various applications.

Claims (6)

As a method for producing a continuous foam, Processing the molding material continuous in the longitudinal direction as crosslinked foaming is suppressed; Preparing two or more processed molding materials, and then forming an interface having an arbitrary shape on one or more of the prepared molding materials by using one or more boundary materials to prevent physical and chemical bonding between the molding materials; A pair of metal plate belts which serve as pressurizing means for suppressing foaming of the molding material and continuously heat in an infinitely orbital movement in opposite directions while being spaced apart at regular intervals, and heat is continuously applied to at least one selected from the metal plate belts. Injecting a molding material having the interface between the belt belts of the continuous pressure crosslinking unit comprising a heating means for supplying the heat sink; Continuously press-crosslinking a continuous molding material that moves with the metal plate belt between metal plate belts using heat continuously transmitted through the metal plate belt; Continuously foaming a molding material continuously exiting the metal sheet belt in a crosslinked state to implement a foam having a hollow structure having an arbitrary shape inside the interface; A method for producing a continuous foam having an internal cavity structure comprising. The method of claim 1, In the interface forming step, the boundary material is a liquid or solid material, or a method of producing a continuous foam with an internal cavity structure, characterized in that it is made of any one or more selected from a molding consisting of a predetermined shape. The method of claim 1, After the continuous foaming step, the step of injecting or inserting at least one selected from a gas, a liquid or a solid material, or a molding having a predetermined shape into the inner cavity of the continuous foam is further added. Method for producing a continuous foam having an internal cavity structure. The method of claim 1, The continuous pressurizing cross section is a method of manufacturing a continuous foam having an internal cavity structure, characterized in that the vertical height adjusting means for adjusting the interval between the metal plate belt in response to the molding material is formed in the interface. The method of claim 1, The continuous pressurizing portion further comprises a pressure means for pressurizing at least one of the metal sheet belt to suppress the foaming of the crosslinked molding material while moving with the metal sheet belt continuous foam having an internal cavity structure Manufacturing method. The method of claim 1, The continuous molding material is a method for producing a continuous foam having an internal cavity structure, characterized in that the thin film form.

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