JP2008302969A - Tube for paper bag with film inner bag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tube for a paper bag with a film inner bag enabling the paper bag with the film inner bag, the innermost layer being formed of a synthetic resin film, to be easily made at a reduced cost without applying an adhesive agent. <P>SOLUTION: The paper bag with the film inner bag has a tubular synthetic resin film tube body 4 and a tubular paper tube body 2 enclosing the tube body 4 wherein the tubular synthetic resin film tube body 4 has a first film layer 4a arranged toward the paper tube body 2 and a second film layer 4b fixed to the first film layer 4a and arranged toward the opposite side of the paper tube body 2, and the first film layer 4a is bonded to the opposite tube body at a lower temperature than the second film layer 4b. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a multilayer bag tube used for manufacturing a multilayer bag, and particularly to a paper bag tube with a film inner bag used for manufacturing a paper bag with an inner film bag.

  Conventionally, a multilayer bag comprising a plurality of layers includes a paper bag comprising an inner bag of a film made of a synthetic resin such as polyethylene (hereinafter referred to as “paper bag with an inner bag”). This paper bag with an inner bag is used in a large amount because it is suitable in terms of airtightness, moisture resistance, cleanliness, and the like.

A paper bag tube with an inner bag (hereinafter referred to as “paper bag tube”) is used as a raw material for making the paper bag with an inner bag.
Here, the “tube” refers to a raw material for bag making in which a layer such as a film or paper is formed and bonded in a cylindrical shape, cut into a certain size, and both ends are left open.

FIG. 9 is a conceptual cross-sectional view of the above-described conventional bag with an inner bag, in which the mouth is opened and the contents are filled.
9, the innermost layer is made of a synthetic resin such as a polyethylene film, and the outer layer is made of a paper material such as kraft paper.

FIG. 10 is a conceptual cross-sectional view of a paper bag tube used for manufacturing the paper bag with the inner bag of FIG.
As shown in FIG. 10, the paper bag 31 with the inner bag of FIG. 9 is manufactured using the paper bag tube 21.
The paper bag tube 21 includes a cylindrical synthetic resin film tube body (hereinafter referred to as “synthetic resin tube body”) 24 and a cylindrical paper tube body 2.
Among these, the cylindrical paper tube body 2 surrounds the synthetic resin tube body 24. The cylindrical paper tube body 2 is a tube body formed of a paper material such as kraft paper.
The synthetic resin tube body 24 is a tube body made of a synthetic resin such as a polyethylene film and made of a single film layer. The synthetic resin tube body 24 is disposed as the innermost layer of the paper bag 31 with the inner bag.

One end 21 a of the inner bag-equipped paper bag tube 21 is a portion that forms the mouth portion 5 of the inner bag-equipped paper bag 21. The paper tube body 2 and the synthetic resin tube body 24 positioned on the one end side 21a are not bonded to each other in the initial state, but an adhesive such as glue is attached to the paper tube body 2 or the synthetic resin tube body 24. 22 are applied to each other so that they cannot be separated from each other.
In this way, the paper tube body 2 and the synthetic resin tube body 3 of the mouth portion 5 are bonded to each other, such as sugar, various powders, foods such as grains or protein, resin pellets, etc. In order to fill the opening 6 between the synthetic resin tube body 24 and the synthetic resin tube body 24 opposite to the synthetic resin tube body 24 as much as possible. It is.
Since the material of the tube body to be bonded is made of synthetic resin and paper, adhesive rubber paste is usually used for the adhesive 22.
Further, the paper tube body 2 and the synthetic resin tube body 24 on the other end side 21b of the paper bag tube are not bonded.

The paper tube body 2 and the synthetic resin tube body 24 on the other end side 21b of FIG. 10 are bent in one direction as shown in FIG. 11, and then the base paper 9 with a cut tape is attached via the adhesive layer 8 of the adhesive. When arranged, the bottom portion 10 of the inner bag-equipped paper bag 31 can be formed and the other end side 21b can be sealed.
FIG. 11 is a conceptual diagram showing the operation of the paper bag with the inner bag of FIG. 9, and particularly shows the state before filling the contents.

  Moreover, in the paper bag 31 with an inner bag of FIG. 11, since the synthetic resin tube bodies 24 which face each other and form the mouth portion 5 are not bonded to each other, the mouth portion 5 is opened as shown in FIG. The contents C can be filled into the opening 6 from 5.

Further, after the housing, as shown in FIG. 12, when the sewing machine sewing machine (not shown) is performed on the one end side 21a of the paper tube body 2 and the synthetic resin tube body 24, the mouth portion 5 can be sealed, thereby the inner bag. The attached paper bag 31 can be used for transportation and storage.
FIG. 12 is a conceptual diagram showing the operation of the paper bag with the inner bag in FIG. 9, and particularly shows a state where the mouth is sealed.

FIG. 13 is a conceptual cross-sectional view showing a conventional paper bag with a film inner bag different from FIG. 9, and particularly shows a state where the mouth is sealed.
As shown in FIG. 13, in a conventional paper bag with an inner bag, an inner bag in which a paper tube body 2 and a synthetic resin film tube body 24 are bonded without using an adhesive 22 such as glue (FIG. 9). There is a paper bag 51 (see, for example, Patent Document 1).
The inner bag-equipped paper bag 51 is manufactured by using a single-layer synthetic resin tube body 24 and an inner bag-equipped tube 41 including the respective paper tube bodies 2 which are an inner layer and an outer layer opposed to the synthetic resin tube body 24. Is.
In this tube 41 with an inner bag, heat is applied to one end side 41a thereof, thereby melting the synthetic resin tube body 24, whereby the synthetic resin tube body 24 is attached to each paper tube body 2 located inside and outside thereof. Adhere.
JP 2002-160742 A

A conventional paper bag tube 21 (FIG. 9) is used to manufacture a paper bag 31 with an inner bag by bonding the synthetic resin tube body 24 and the paper tube body 2 with an adhesive 22 so that they cannot be separated from each other. Therefore, there is a problem that the application work of the adhesive 22 is complicated, and there is a problem that the manufacturing cost of the paper bag 31 with the inner bag increases because the adhesive 22 is provided.
Further, in the conventional paper bag tube 41 (FIG. 13) that does not use the adhesive 22, the paper tube body 2 is disposed on the inner layer and the outer layer facing the synthetic resin tube body 24, respectively, and is melted by heating. Since the resin tube body 24 is bonded to the paper tube bodies 2 on both sides at the same time, the innermost layer is the synthetic resin tube body 24 and the synthetic resin tube body 24 directly forms the opening 6. The paper bag tube cannot be used, and as a result, the adhesive 22 must be adhered.

  In view of the above-mentioned circumstances, the present invention can easily manufacture a paper bag with a film inner bag in which the innermost layer is formed of a synthetic resin film without performing an adhesive application operation, and can reduce the manufacturing cost. An object of the present invention is to provide a tube for a paper bag with a film inner bag.

  The paper bag tube with a film inner bag according to the first aspect of the present invention comprises a cylindrical synthetic resin film tube body and a cylindrical paper tube body surrounding the synthetic resin film tube body, and the synthetic resin film tube The body comprises at least a first film layer disposed adjacent to the paper tube body and a second film layer disposed to be exposed to the opposite side of the paper tube body with respect to the first film layer. The first film layer is characterized by melting at a lower temperature than the second film layer and adhering to the opposing tube body.

  The paper bag tube with a film inner bag according to claim 2 of the present application is the tube for paper bag with a film inner bag according to claim 1, wherein the second film layer is formed on the opposite tube body, and the first film layer is formed on the opposite tube body. It is characterized in that it is not bonded at a temperature at which it is bonded to the opposing tube body, but is bonded at a temperature higher than this temperature.

  The paper bag tube with a film inner bag according to claim 3 of the present application is the paper bag tube with a film inner bag according to claim 1, wherein the synthetic resin film tube body is an innermost layer of the paper bag tube with a film inner bag. It is characterized by being arranged.

  The paper bag tube with a film inner bag according to claim 4 of the present application is the tube for paper bag with film inner bag according to claim 1, wherein the first film layer is bonded to the opposing tube body and the second film. The layers are characterized in that they are not bonded to the opposing tube body.

  The tube for a paper bag with a film inner bag according to claim 5 of the present invention is the tube for a paper bag with a film inner bag according to claim 1, wherein the second film layer is opposed after the paper bag with the film inner bag is filled with the contents. It is characterized by being bonded to the tube body.

  A paper bag tube with a film inner bag according to the present invention is a paper bag tube with a film inner bag comprising a cylindrical synthetic resin film tube body and a cylindrical paper tube body surrounding the synthetic resin film tube body. The synthetic resin film tube body includes a first film layer disposed adjacent to the paper tube body, and a second film disposed to be exposed toward the opposite side of the paper tube body with respect to the first film layer. The first film layer is melted at a temperature lower than that of the second film layer so as to adhere to the opposite tube body. By heating, the first film layer of the synthetic resin film tube body adheres to the paper tube body facing it without using an adhesive, and the synthetic resin film tube With the film inner bag in which the innermost layer is formed of a synthetic resin film without applying the adhesive, so that the second film layer of the body can be prevented from adhering to the opposing tube body. The paper bag can be easily manufactured, and the manufacturing cost of the paper bag with the film inner bag can be reduced by the amount of the adhesive and its application work.

  The tube for a paper bag with a film inner bag (hereinafter referred to as “paper bag tube”) of the present invention will be described in detail in the following examples.

FIG. 1 is a conceptual cross-sectional view of a paper bag with a film inner bag manufactured by a paper bag tube according to an embodiment of the present invention, and shows a state in which contents are filled from a mouth portion.
As shown in FIG. 1, a paper bag with an inner bag (hereinafter referred to as “paper bag with an inner bag”) 11 has an innermost layer formed of a synthetic resin such as a polyethylene film, and the outer layer is made of kraft paper. It is formed with paper materials such as. The paper bag tube 1 according to the embodiment of the present invention is used for manufacturing the paper bag 11 with the inner bag.

2 is a conceptual cross-sectional view of the paper bag tube of the present invention used for manufacturing the paper bag of FIG. 1, and FIG. 3 is a conceptual end view of the paper bag tube of FIG. 1 to FIG. 8 to be described later, the same parts are denoted by the same reference numerals, and among the reference numerals shown in FIG. 1 to FIG. 8, the same parts as those in FIG. 9 to FIG. Show.
As shown in FIGS. 2 and 3, the paper bag tube 1 includes a cylindrical paper tube body 2 and a cylindrical synthetic resin film tube body 4 (hereinafter referred to as “synthetic resin tube body”). Yes.
Among these, the paper tube body 2 surrounds the synthetic resin tube body 4. The paper tube body 2 is formed of a paper material such as kraft paper.
The synthetic resin tube body 4 is arranged as the innermost layer of the paper bag 11. The synthetic resin tube body 4 is formed of a polyethylene film.

4 is a conceptual diagram showing the structure of a synthetic resin tube body constituting the paper bag tube of FIG.
The structure of the above-described synthetic resin tube body 4 will be further described. As shown in FIGS. 4 and 3, the synthetic resin tube body 4 includes at least a first film layer 4a and a second film layer 4b. .

  Among these, the first film layer 4 a is a layer disposed adjacent to the paper tube body 2, in other words, a layer facing the paper tube body 2 as shown in FIG. 2.

  Moreover, the 2nd film layer 4b is exposed and arrange | positioned toward the opposite side to the paper tube body 2 with respect to the 1st film layer, as shown in FIG. The second film layer 4b is fixed to the first film layer 4a. Moreover, since the synthetic resin tube body 4 is arrange | positioned as the innermost layer of the paper bag 11, this 2nd film layer 4b opposes the 2nd film layer 4b through the opening part 6 (FIG. 1). .

  Further, the first film layer 4a shown in FIG. 2 is not bonded to the paper tube body 2, and the second film layer 4b shown in FIG. 2 is also bonded to the opposing film layer (second film layer 4b). Not done.

  The first film layer 4a is a layer that melts at the first set temperature and thereby adheres to the opposing paper tube body 2. The second film layer 4b is a layer that melts at a second temperature higher than the first set temperature and thereby adheres to the opposing tube body. Therefore, the first film layer 4a is a layer that melts at a lower temperature than the second film layer 4b and adheres to the opposing tube body.

FIG. 5 is a conceptual diagram showing the operation of the paper bag with the inner bag of FIG. 1, and particularly shows a state before filling the contents.
As shown in FIG. 5, at the other end 1b of the paper bag tube 1, the synthetic resin tube body 4 is not bonded to the paper material tube body 2, and the adhesive adhesive layer 8 and the cut tape are used as in the prior art. By the sealing means 7 comprising the attached bottom cover paper 9, the bottom portion 10 of the inner bag-attached paper bag 11 can be formed, and the other end 1b can be sealed.

Next, the operation of the paper bag tube 1 will be described.
FIG. 6 is a conceptual diagram showing an operation of applying heat to the paper bag tube 1 of FIG. 2, and in particular, FIG. 6A shows a state before heat is applied, and FIG. 6B shows a state where heat is applied. FIG.
When the synthetic resin tube body 4 of the paper bag tube 1 is not bonded to the paper material tube body 2 as shown in FIGS. 2 and 6 (a), as shown in FIG. 6 (a), a pair of seal bars An adhesive means 61 having 61a and 61b is prepared. As shown by an arrow A and FIG. 6B, the pair of seal bars 61a and 61b is heated at a first temperature, and the pair of seal bars 61a and 61b The paper bag tube 1 is sandwiched (hereinafter, this process is referred to as “first heat treatment”).

Then, as shown in FIG. 7A and FIG. 1, the first film layer 4 a is melted and bonded to the opposing paper tube body 2. On the other hand, the second film layer 4b does not melt at the first set temperature and does not adhere to the second film layer 4b, which is a tube body of the opposing synthetic resin tube body 4.
FIG. 7 is a diagram showing the action of the paper bag tube according to the operation of FIG. 6B. In particular, FIG. 7A shows the first of the synthetic resin tube body facing the second film layer of the synthetic resin tube body 4. It is a figure which shows a mode that it can isolate | separate from a 2nd film.

  When this first heat treatment is performed on one end side 1a of the paper bag tube 1 in which the synthetic resin tube body 4 is not bonded to the paper material tube body 2, the second film layer 4b opposed to the second film layer 4b. Thus, the mouth portion 5 can be opened as shown in FIG. 1, and the contents C can be filled into the opening portion 6 of the paper bag 11 from the mouth portion 5.

  Further, since the first film layer 4a is adhered to the paper tube body 2, when the contents C are filled from the mouth portion 5, the contents C can be filled into the opening 6 as reliably as possible. Become.

  As shown in FIGS. 2 and 6 (a), the second film 4b of the synthetic resin tube body 4 on the one end side 1a of the paper bag tube 1 is the second of the synthetic resin tube body 4 which is an opposing tube body. When the film 4b is not bonded, the pair of seal bars 61a and 61b of the bonding means 61 is heated at a second temperature higher than the first temperature as shown by the arrow A and FIG. The paper bag tube 1 is sandwiched between the pair of seal bars 61a and 61b (hereinafter, this process is referred to as "second heat treatment").

  Then, as shown in FIG. 7B and FIG. 8, the second film layer 4b is melted and thereby adhered to the opposing second film layer 4b.

Accordingly, when this second heat treatment is performed after the inner heat-treated paper bag 11 (FIG. 7 (a)) is filled with the contents C as shown in FIG. Can be sealed.
FIG. 7B is a diagram illustrating a state in which the second film layer of the synthetic resin tube body is bonded to the opposing second film layer of the synthetic resin tube body in an inseparable manner. FIG. 8 is a conceptual diagram showing the operation of the paper bag of FIG. 1, and particularly shows a state where the mouth is sealed.

Moreover, as the paper bag tube 1 of the present invention, a tube having the following conditions is given as a preferred embodiment.
That is, as the paper tube body 2, a kraft paper having two layers of 78 g / m ² stacked and bonded is used.
The synthetic resin tube body 4 includes a first film layer 4a and a second film layer 4b, and the total thickness of the synthetic resin tube body 4 is 0.08 mm (surface tension 42 mN / m).
Further, the synthetic resin tube body 4 is obtained by fixing the first film layer 4a and the second film layer 4b to each other by film formation by an inflation method.
The first film 4a is mainly composed of linear low density polyethylene (L-LDPE), which has better low-temperature sealability than high pressure polyethylene (LDPE).
Further, the surface of the first film layer 4a is subjected to a surface modification treatment for improving the adhesion between the first film layer 4a and the paper tube body 2, for example, a typical treatment for the surface modification. Perform corona treatment known as.
The second film 4b is formed with a blend composition of 50% to 75% high density polyethylene (HDPE) and 50 to 25% high pressure polyethylene (LDPE).
Moreover, in order to prevent blocking in the first heat treatment (the second film 4b facing each other closes the mouth portion 5 by fusion) and to improve the opening of the paper bag 11 with the inner bag, general-purpose anti-blocking An agent or a slip agent (an agent that makes the second films 4b facing each other slip easily) is added. In particular, it is preferable to add a fatty acid amide as the slip agent.
Moreover, this paper bag tube 1 can be used as a raw material when manufacturing a paper bag with an inner bag of a so-called gusseted bag (folded bag).
The types, thicknesses, and properties of the paper tube body 2 and the types, thicknesses, and properties of the first film layer 4a and the second film layer 4b of the synthetic resin tube body 4 are as described above. Needless to say, the preferred conditions are not limited.

The conditions for the first heat treatment described above are preferably as follows.
That is, the first temperature is 135 ° C. to 145 ° C. (the room temperature during the first heat treatment is 18 ° C.).
The heating time by the bonding means 61 is 8 seconds to 10 seconds. The pressure applied when the paper bag tube 1 is sandwiched by the bonding means 61 is 0.6 ± 0.1 MPa. Further, when the pressure is 0.6 ± 0.1 MPa in this way, the first film layer 4a of the synthetic resin film body 4 in the gusseted bag and the paper are compared with the case where the pressure is 0.2 Mpa or less. Bonding with the tube body 2 can be performed as uniformly as possible.
Further, when the first temperature is 135 ° C. to 145 ° C., the tube body in which the second film layer 4b faces even when heated for the heating time as compared with the case where the first temperature is 150 ° C. or higher. It is possible to prevent the possibility of being fused to the surface as much as possible.
Moreover, it is preferable to perform a corona treatment in advance as the first film layer 4a, and in this way, the first film layer 4a and the paper tube body 2 can be bonded as reliably as possible, and the second film layer 4a The possibility that the films 4b adhere to each other due to melting can be further prevented as much as possible.

Next, the conditions for the second heat treatment are preferably as follows.
The second temperature is 230 ° C. or higher (the room temperature during the second heat treatment is 18 ° C.).
The heating time at the second temperature is 8 to 10 seconds. The pressure by the bonding means 61 is 0.6 ± 0.1 MPa. In addition, the conditions in the above-mentioned second heat treatment can achieve the adhesion between the second film layers 4b under substantially the same adhesion conditions as those of other paper bags with a polyethylene tube inner bag.

  As described above, the paper bag tube 1 according to the embodiment of the present invention includes the cylindrical synthetic resin tube body 4 and the cylindrical paper tube body 2 surrounding the synthetic resin tube body 4, The synthetic resin tube body 4 is a first film layer 4a disposed adjacent to the paper tube body 2 and a second film layer exposed to the opposite side of the paper tube body 2 with respect to the first film layer. The first film layer 4a is melted at a first temperature lower than the second temperature, which is the melting temperature of the second film layer 4b, and is bonded to the opposing tube body 2. Therefore, by heating the paper bag tube 1 at the low temperature, the first film layer 4a of the synthetic resin tube body 4 adheres to the paper tube body 2 opposed thereto without using the adhesive 22 and is synthesized. Resin tube body The second film layer 4b can be prevented from adhering to the opposing tube body (second film layer 4b), so that the innermost layer can be made of a synthetic resin without performing the operation of applying the adhesive 22. The paper bag 11 with the inner bag formed by the film can be easily manufactured, and the manufacturing cost of the paper bag 11 with the inner bag can be reduced by the amount of the adhesive 22 and the application work.

  Further, in the conventional paper bag tube 21, the adhesive 22, which is an adhesive means, is made of a sticky rubber paste as compared with starch paste generally used for the purpose of bonding paper together. In the application work, the surroundings must be cleaned, and the cleaning work is complicated. However, in the present invention, since the adhesive 22 is not used, the application operation of the adhesive 22 itself is not performed, and therefore the peripheral cleaning operation is not required.

  Moreover, in the paper bag tube 1 with an inner bag in which the innermost layer is formed of a synthetic resin film, the tube body 2 is bonded to the synthetic resin tube body 4 facing the paper tube body 2 and the second film layer 4b is opposed to the tube body. Since the state which is not adhere | attached on a certain 2nd film 4b can be maintained, when filling the content C from the opening part 5, the content C can be filled in the opening part 6 as reliably as possible.

  Further, in the paper bag tube 1 of the present invention, the second film layer 4b does not adhere to the opposing tube body at the first temperature at which the first film layer 4a adheres to the opposing tube body. Since the bonding is performed at the second temperature higher than the first temperature, the mouth portion 5 can be sealed as reliably as possible by the bonding at the higher second temperature. Further, in this paper bag tube 1, the first film layer 4a and the paper tube body 2 and the second film layer 4b can be bonded together using a common bonding means 61. The manufacture of the paper bag 11 with the inner bag is simplified.

Further, in the conventional paper bag tube 51 (FIG. 13), the melting when the synthetic resin tube body 4 is heated occurs both inside and outside the synthetic resin tube body 4, so that the synthetic resin tube body 4 is melted by the melting. Adhesion is simultaneously performed between the inner tube body facing the synthetic resin tube 4 and the outer tube body facing each other, so that the mouth portion 5 and the opening portion 6 are closed before the container C is filled. There was a risk of blockage.
However, the paper bag tube 1 of the present invention comprises a synthetic resin tube body 4 surrounded by a paper tube body 2, a first film layer 4a disposed adjacent to the paper tube body 2, and a first film. At least a second film layer 4b arranged to be exposed to the opposite side of the paper tube body 2 with respect to the layer 4a, and the first film layer 4a has a lower temperature than the second film layer 4b. Therefore, the synthetic resin tube body 4 can be bonded to the paper tube body 2 by one-side melting of the synthetic resin tube body 4, thereby allowing the synthetic resin tube body 4 to It can be arranged as the innermost layer of the paper bag tube 1.

  Further, as shown in FIG. 1, the paper bag tube 1 of the present invention is bonded to the tube body facing the first film layer 4a, and the second film layer 4b is not bonded to the facing tube body. In such a paper bag tube 1, the contents can be filled into the opening 6 as reliably as possible.

  Further, the paper bag tube 1 of the present invention may be in a state where the second film layer 4b is bonded to the opposite tube body (in this embodiment, the second film layer 4b). For example, as described above, the paper bag tube 1 may be such that after the contents are filled in the paper bag 1, the mouth portion 5 of the paper bag 11 with the inner bag is sealed by the second heat treatment.

  Of course, the paper bag tube 1 of the present invention may be a paper bag tube 1 with an inner bag in a state before the first heat treatment as shown in FIG.

  Moreover, the synthetic resin film tube body 4 used for the paper bag tube 1 of this invention should just have at least the 1st film layer 4a and the 2nd film layer 4b, and the synthetic resin film tube body 4 is As in the above-described embodiment, the first film layer 4a and the second film layer 4b may be composed of two film layers disposed adjacent to each other. The synthetic resin film tube body 4 may be composed of three or more film layers including the first film layer 4a and the second film layer 4b. For example, the synthetic resin film tube body 4 may be a multilayer film in which an aluminum foil layer and other layers are interposed between the first film layer 4a and the second film layer 4b.

  In addition, in order to take out the stored item C from the inner bag-attached paper bag 11 filled with the stored item C and the mouth portion 5 sealed, similarly to the conventional inner bag-attached paper bags 31, 51, the bottom backing paper 9 with a cut tape is used. The bottom 10 may be unsealed using a cut tape (not shown), or the mouth 5 may be unsealed with a cutting means such as a cutter.

FIG. 1 is a conceptual cross-sectional view of a paper bag with a film inner bag manufactured by a paper bag tube according to an embodiment of the present invention, and shows a state in which contents are filled from a mouth portion. FIG. 2 is a conceptual cross-sectional view of a paper bag tube of the present invention used for manufacturing the paper bag of FIG. 3 is a conceptual end view of the paper bag tube of FIG. 4 is a conceptual diagram showing the structure of a synthetic resin tube body constituting the paper bag tube of FIG. FIG. 5 is a conceptual diagram showing the operation of the paper bag with the inner bag of FIG. 1, and particularly shows a state before filling the contents. FIG. 6 is a conceptual diagram showing the operation of applying heat to the paper bag tube of FIG. 2, and in particular, FIG. 6 (a) shows the state before applying heat and FIG. 6 (b) shows the state of applying heat. It is. FIG. 7 is a diagram showing the action of the paper bag tube according to the operation of FIG. 6B. In particular, FIG. 7A shows the second of the synthetic resin tube body facing the second film layer of the synthetic resin tube body. It is a figure which shows a mode that it can isolate | separate from a film layer, FIG.7 (b) adheres the 2nd film layer of a synthetic resin tube body to the 2nd film layer of the synthetic resin tube body which opposes so that separation is impossible FIG. FIG. 8 is a conceptual diagram showing the operation of the paper bag of FIG. 1, and particularly shows a state where the mouth is sealed. FIG. 9 is a conceptual cross-sectional view of the above-described conventional bag 1 with an inner bag, and shows a state in which the mouth is opened and the contents are filled. FIG. 10 is a conceptual cross-sectional view of a paper bag tube used for manufacturing the paper bag with the inner bag of FIG. 9. FIG. 11 is a conceptual diagram showing the operation of the paper bag with the inner bag of FIG. 9, and particularly shows a state before filling the contents. FIG. 12 is a conceptual diagram showing the operation of the paper bag with the inner bag of FIG. 9, and particularly shows a state where the mouth is sealed. FIG. 13 is a conceptual cross-sectional view showing a conventional paper bag with a film inner bag different from FIG. 9, and particularly shows a state where the mouth is sealed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Tube for paper bags with a film inner bag 2 ... Paper tube body 4 ... Synthetic resin film tube body 4a ... First film layer 4b ... Second film layer 11 ... Paper bag with film inner bag

Claims (5)

In a tube for a paper bag with a film inner bag comprising a cylindrical synthetic resin film tube body and a cylindrical paper tube body surrounding the synthetic resin film tube body,
Synthetic resin film tube body
A first film layer disposed adjacent to the paper tube body;
And at least a second film layer disposed so as to be exposed to the opposite side of the paper tube body with respect to the first film layer,
The first film layer is melted at a temperature lower than that of the second film layer and bonded to an opposing tube body.   The second film layer is not bonded to the opposing tube body at a temperature at which the first film layer is bonded to the opposing tube body, but is bonded at a temperature higher than the temperature. The tube for paper bags with a film inner bag of 1.   The tube for a paper bag with a film inner bag according to claim 1, wherein the synthetic resin film tube body is arranged as an innermost layer of the tube for a paper bag with a film inner bag.   The tube for a paper bag with a film inner bag according to claim 1, wherein the first film layer adheres to the opposing tube body, and the second film layer does not adhere to the opposing tube body.   2. The tube for a paper bag with a film inner bag according to claim 1, wherein the second film layer is adhered to the opposing tube body after the contents are filled in the paper bag with the film inner bag.

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