JPH04150808A - Air cushion bag - Google Patents

Abstract

PURPOSE:To give a sufficient resistance against external impulses and not to bring about creases and deformation at the adhesion and also to efficiently produce air cushion bags through a continuous process, by using a specified adhesive to form an adhesion of a surface film and a backface film. CONSTITUTION:A surface film 12 and a backface film 3A are superimposed to make an air cushion bag. The surface film 12 and the backface film 3A are bonded in the peripheral edge except the air feed inlet 7. These are partially bonded at spotted points 9 in the place except the periphery. The surface film 12 and the backface film 3A is made of a plastic film having a tensile strength more than 200kgf/cm<3> and the adhesion between the surface film 12 and the backface film 3A are bonded by the adhesive 4 having 5-20kgf/cm<3> tensile stress on pulling it two times the length according to JIS K-7113.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a bag-like article for an air cushion used, for example, as a cushioning material, a cushion, an air column, an air mattress, and the like.

[Conventional technology]

The front film and the back film are overlaid, their edges are glued, and the areas other than the edges are:
Air cushion bags are bonded with multiple spot-shaped partial adhesive parts, and the adhesive part between the front film and the back film is heat-sealed using the heat fusion ability of the front and back plastic films. is formed by. In the above-mentioned bag-like article in which the front film and the back film are bonded together by heat sealing, the pressure and temperature during heat sealing are set to be sufficiently high so that sufficient adhesive strength is obtained at the bonded portion by heat sealing. Alternatively, the adhesive portion is formed by heating and pressing for a sufficiently long time.

[Problem to be solved by the invention]

By the way, when forming the adhesive part of the stacked body of the front film and the back film by heat sealing, if the pressure and temperature at the time of heat sealing are increased, the adhesive part and its surrounding area, that is, the hot roll will hit. Parts have the disadvantage of deteriorating the quality of printed designs, especially those added for the purpose of giving design characteristics, because the parts may undergo thermal deformation, wrinkles, or even changes in gloss. . In addition, sufficient heating and pressure bonding time during heat sealing leads to a decrease in productivity and is not suitable as a method for production on an industrial scale. In order to solve these problems, forming an adhesive between the front film and the back film using an adhesive may be considered. When the bag receives an instantaneous impact from the outside, the stress is concentrated on the end of the spot-shaped partial adhesive portion, so there is a high risk of the bag breaking from that portion. On the other hand, the present invention utilizes a specific adhesive to form the bonded portion between the front film and the back film. Effective distribution of instantaneous impact forces,
For air cushions that are designed to reduce the amount of stress, there is no deformation, shrinkage, or change in gloss at the bonded parts of the front and back plastic films, and it can be manufactured efficiently through high-speed production. Provides bags-like items.

[Means to solve the problem]

In the air cushion bag-like article of the present invention, a front film and a back film are overlapped, and the front film and the back film are bonded to each other at their edges except for the air inlet, In addition, the parts other than the edges are adhered by spot-like partial adhesion, and the front film and back film are made of plastic film with a tensile strength of 200 kg f/c 2 or more, and , 2 according to JIS K-7113 was used to form the adhesive part between the front film and the back film.
An adhesive having a tensile stress of 5 to 20 kg f/cg when stretched for double length is used. In the air cushion bag of the present invention having the above structure, the front film and the back film are made of, for example, linear low density polyethylene or high density polyethylene. Polypropylene or a mixed resin such as these resins and low density polyethylene, or a plastic film made of nylon, polyester, etc. and having a tensile strength of 200 kg f/am1 or more is used. In particular, a linear low-density polyethylene film or a film made of a mixed resin of linear low-density polyethylene and low-density polyethylene is suitable in terms of cost. In addition, the adhesive portion between the front film and the back film, that is, the adhesive portion at the edge of the stacked body of the front film and the back film, and the numerous spot-shaped partial adhesive portions in areas other than the edge portion. Adhesives used for this purpose have physical properties such as a tensile stress of 5 to 20 kg f/cm when stretched at double length according to JIS K-7113, and are, for example, prepolymer type adhesives having incyanate groups. Adhesives, two-component adhesives consisting of a main agent made of polyether polyol or a resin modified with urethane or epoxy and a curing agent having an isocyanate group are used. An adhesive with a tensile stress of 5 to 20 kg f/cm" when stretched for a long time has a tensile stress of 5 to 20 kg f/cm" when the cured film of the adhesive is stretched to double the length at room temperature. If the tensile stress of the adhesive used to bond the front film and the back film when stretched at double length according to JIS K-7113 is less than 5 kg f/cm, Sufficient adhesion performance cannot be obtained, and the bow tension stress exceeds 20 kg.
f/cg", the tensile modulus of the adhesive layer in the air cushion bag becomes too high, making it difficult to effectively disperse the instantaneous impact force applied to the edge of the adhesive layer. , it becomes impossible to measure the relaxation, and the air cushion becomes insufficiently resistant to the instantaneous impact.Applying area and amount of the above-mentioned adhesive when forming the bond between the front film and the back film is set as appropriate depending on the use of the air cushion bag. For example, when the air cushion is used as a cushioning material for articles that are easily damaged, the area and amount of adhesive applied are determined as follows: A small amount is fine, but if it is used as a pillow or cushion, it is necessary to apply a larger amount.Also, at the edge of the overlapping body of the front film and the back film, the width is about 5 to 2 C) am. In addition, the partial adhesive parts formed in spots other than the edges of the bag are, for example, a group of many circular dots with a diameter of about 20 to 40 mm, or a group of circular dots with a width of 3 to 8 mm and a length of 6 mm.
It is formed by a large number of cross-shaped dots made by crossing lines of about 0 to 90 iIm, and is made so that a part of the bag does not become a sealed part separated by these partial adhesive parts, i.e. The bag is formed into a substantially uniform spot shape so that the entire interior of the bag can be communicated with. In addition, if the amount of adhesive used to form the adhesive part is applied too much than necessary, the adhesive layer will tend to shift, and if it is too small, the initial adhesive force of the adhesive layer will be reduced, resulting in poor adhesion. The adhesive should be 1 to 10g (solid content) 7m
It is preferable to apply within the range of 2. The adhesive portion between the front film and the back film is obtained by applying a predetermined adhesive to either one of the front film or the back film to a portion where the adhesive is to be bonded between the two.
The solvent in the adhesive is evaporated by blowing hot air at about 40 to 80℃, and after the adhesive layer surface becomes sticky, a lamination film is applied, and then it is pressed with a heated roll at about 80℃. formed by In the above process, in the drying process for evaporating the solvent in the adhesive after applying the adhesive, the temperature of the hot air is kept sufficiently low (
However, it is preferable to increase the air volume to prevent the film from stretching during the adhesive drying process. In addition, the nip temperature and nip pressure of the rolls are lowered in the heat and pressure bonding process after the laminating film is brought into contact, and the winding pressure in the subsequent winding process is also weakened to prevent aging at low temperatures. It is preferable to do this thoroughly.

[Function] In the air cushion bag-like article of the present invention, the front film and the back film are overlapped, and the front film and the back film are arranged at the edges thereof, except for the air inlet. In addition, in areas other than the edge areas, the surface film and the back film are partially adhered in spots, and the surface film and the back film are
It is made of a plastic film that has a tensile strength of 2 kg f/cm" or more, and the adhesive part between the front film and the back film is rated 2 according to JIS K-7113.
It is bonded with an adhesive having a tensile stress of 5 to 20 kg f/cra when stretched at double length. Provides sufficient bag breakage resistance as required2
A plastic film with a bow tensile strength of 00 kg f/c+w" or more is used, and has a sufficient effect on bag breakage resistance. In addition, an air cushion usually has a large number of spot-shaped partial adhesive parts. When a bag receives an instantaneous impact from the outside, stress is concentrated at the end of the spot-shaped partially bonded part, so there is a risk of the bag breaking from that part. In the air cushion bag of the present invention having the above configuration, the adhesive portion between the front film and the back film has a tensile stress of 5 to 20 kg f/cm when stretched at double length according to JIS K-7113. Because they are bonded with an adhesive that has specific physical properties, the tensile modulus of the adhesive layer that bonds the front film and back film is low, and for this reason, when used as an air cushion, The instantaneous impact force applied to the edge of the adhesive layer, which is the edge of the partially bonded portion, is extremely effectively dispersed and alleviated. In other words, in the bag-like air cushion of the present invention, when an instantaneous impact force is applied from the outside, such as when sitting on a cushion, the adhesive layer disperses the impact force. This effect is extremely effective. [Examples] Below, the specific structure of the bag-like article for air cushion of the present invention will be explained based on manufacturing examples. Example 1 In FIGS. 1 and 2, from the take-up roll indicated by the reference numeral 2, a 100c-glue near low density polyethylene film (thickness 7
5μ, tensile strength: 250 kgf/cm”) 3
2), and on the back side (non-printing side) of the film 3,
Polyether polyol two-component adhesive (JIS K-7
Tensile stress at double length tension using 113 10 kg
f/am'') 4 for both left and right ears s5.6, excluding the air inlet planned portion 7 (width 10s + w, and for every 50 cm length of the film 3, the film 3 A line part 8 with a length of 20 mm parallel to the short side of the line part 8, and a large number of spot groups formed by a cross shape 9 made by crossing a line with a width of 5 m and a length of 90 mm inside these parts. After applying the coating amount of 5 g (solid content) to 7 m3 of the application part by roll coating method, the solvent in the adhesive is evaporated by passing it through a drying oven 10 at 80 ° C., and the back side with adhesive indicated by code 3A is A film was obtained.Subsequently, a linear film having a width of 100c+s that was rewound from the winding roll 11 was applied to the back film 3A.
A surface film 12 made of a full-surface printed film of low density polyethylene (thickness 75u, tensile strength: 250 kgf/c 3) is attached to the back surface (non-printed surface) of the surface film 12 and the adhesive coated surface of the back film 3A. While stacking them so that they are in contact with each other, they are heated at 80"C and laminated using pressure rolls 13 and 14 to form a continuum of bag-like products for air cushions indicated by reference numeral 1, and then This was wound up on a take-up roll 15.The applied area of the many spots of adhesive forming the aforementioned cross shape 9 corresponded to approximately 7% of the entire plane, and the area other than the area where the sealing part was to be formed was Furthermore, the production line for the continuous bag-like body for air cushions by the above-mentioned continuous process was operated at a speed of 30 m/ff1i.
I was able to maintain n. Thereafter, the continuous body of air cushion bag-like material obtained by the above-mentioned continuous process is cut along the center line of the bonded part forming the linear portion 8 with a width of 20+sm parallel to the short side of the continuous body. l 00CO, which is an example product of the present invention.
A bag-like material for an air cushion of IX 50CII+ was obtained. There were no wrinkles or deformation due to shrinkage in the adhesive part of the air cushion bag, and a single letter or other pattern was printed beautifully on the outer surface of the front film and the back film. It was being served. In addition, after attaching the air supply pipe to the air cushion bag-like object using a conventional method, it was used as a pinerest for sitting, and when an external shock was applied by sitting, the sealed part forming the edge part There was no bag breakage from any of the spot-like partially bonded portions, and sufficient impact resistance was obtained. Example 2 70 parts by weight of linear low density polyethylene,
A film made of a mixed resin of 10 parts by weight of low density polyethylene and 20 parts by weight of high density polyethylene (thickness 70μ, tensile strength: 245 kg f/
A front film made of polyethylene film with a width of 50cm+m with a full-scale print of a single character, etc.
Polyether polyol two-component adhesive (JIS K-7
Tensile response at double length tension by 113 10 kg f
/cm"), and by the same continuous process as in Example 1, remove the air inlet planned areas on the left and right ears on the back side (non-printing side) of the surface film. Width 10
Adhesion is applied to the linear portion of width 2 (1+m) parallel to the short side of the film, and a large number of circular spot groups of diameter path 20a+m inside the linear portion of the film for every 50 cs of film length. Apply the agent to the application area in an amount of 5g (solid content)
After applying the solution to an area of 7 m 3 , the same process as the corresponding process of Example 1 was followed to obtain a winding roll of a continuous bag-like material for an air cushion. The area of the adhesive in the form of a large number of circular spots corresponded to approximately 11% of the entire plane, and was applied approximately evenly to the area other than the area where the sealing portion was to be formed. Furthermore, the speed of the production line for the continuous body of air cushion bags through this continuous process was able to be maintained at 30 m/min. Thereafter, the obtained continuum of air cushion bag-like material is cut along the center line of the bonded part that forms a linear portion with a width of 20++no parallel to the short side of the continuum. A bag-like product for an air cushion measuring 50 cm x 50 cm was obtained as an example product. There were no wrinkles or deformation due to shrinkage in the adhesive part of the air cushion bag, and a single letter or other pattern was printed beautifully on the outer surface of the front film and the back film. It was being served. In addition, after attaching the air supply pipe to the air cushion bag-like object using a conventional method, it was used as a pinerest for sitting, and when an external shock was applied by sitting, the sealed part forming the edge part The bag did not break from the spot-like partially bonded portion, and sufficient impact resistance was obtained. Comparative Example 1 Two take-up rolls of the same film as the 100 cm glue near-load density polyethylene film used in Example 1 were prepared, and by heat sealing, the air cushion bag shape obtained in Example 1 was prepared. A continuum of bag-like objects was obtained for comparison that corresponds to the object continuum. In order to prevent wrinkles or deformation due to shrinkage from occurring in the heat-sealed part of the obtained bag-like product, and to obtain sufficient adhesive strength as an air cushion, the heat-sealing process is necessary. The speed had to be 10 m/min or less. Comparative Example 2 A low density polyethylene film with a width of 100 cm (thickness 75 u,
Using two take-up rolls with a tensile strength of 150 kg f/cm" and the same adhesive as that used in Example 1, the following steps were carried out in the same manner as in Example 1. A continuum of bag-like articles for air cushions for comparison was obtained through a continuous process, and then this was cut at predetermined positions to obtain bag-like articles for air cushions for comparison. After attaching the air supply pipe to the air cushion bag-like object using a conventional method, it was used as a pinerest for sitting, and when an external shock was applied to it by sitting, the film on the front and back sides stretched. Comparative Example 3 In the process of Example 2, a polyester polyol two-component adhesive ( JIS K-7113
Tensile response at double length tension due to 70 kg f/
c+w''), and the same process as the corresponding process of Example 2 was carried out except for that, to obtain a bag-like article for an air cushion for comparison.The obtained bag-like article for an air cushion. However, when the air inlet pipe was attached using a conventional method and then used as a cushion and subjected to an external impact due to sitting on it, the bag broke from the partially bonded part, indicating that the impact resistance was insufficient. Ta.

【Effect of the invention】

The air cushion bag of the present invention has sufficient resistance to external impact, does not cause wrinkles or deformation at the bonded part, can be efficiently produced by continuous production, and has a high cost. Quality air cushion bags can be obtained through mass production.

[Brief explanation of drawings]

FIG. 1 is a plan view illustrating the part where the adhesive is applied to the film when manufacturing the air cushion bag of the present invention, and FIG. 2 is a plan view of the bag for the air cushion of the present invention. It is an explanatory view showing an example of a manufacturing process of a continuous body of bag-like objects which are precursors of bag-like objects. 1... Continuous body of bag-like material for air cushion, 2.11... Wind-up roll of film used for bag-like material for air cushion, ... Back film.・・・Adhesive, ・・・Air inlet, ・・・Partial adhesive part. 2...Surface film.

Claims (1)

[Claims] 1. The front film and the back film are overlapped, and the front film and the back film are bonded at their edges except for the air inlet, and
In areas other than the edges, the front film and the back film have a tensile strength of 20
An adhesive that is made of a plastic film with a strength of 0 kgf/cm^2 or more, and whose adhesive part between the front film and the back film has a tensile stress of 5 to 20 kgf/cm^2 when stretched at double length according to JISK-7113. A bag-like article for an air cushion, characterized by having an adhesive part made of.