JP4856115B2 - Gas sampling bag and method of manufacturing the same - Google Patents

Description

  The present invention relates to a gas sampling bag and a method for manufacturing the same, and more particularly to a gas sampling bag used for measuring an odor or measuring a component in a sample gas and a method for manufacturing the same.

  Conventionally, a gas sampling bag equipped with a valve body for intake and exhaust has been used to collect various gases such as sulfurous acid gas, which are the main cause of air pollution, as samples, and to measure their concentrations or analyze various contents. It has been. In addition, gas sampling bags are often used in the measurement and analysis of volatile organic compounds (hereinafter referred to as “VOCs”) such as solvents used in breath and offensive odor measurement or in various factories. Such a gas sampling bag does not permeate to the outside even with some components of the collected gas, and does not change various gases with unknown composition, and is not affected by the outside. Storage is required, and its performance is a very important factor. In other words, regarding the material of the gas sampling bag body, it is necessary to select a material that has low permeability and is excellent in terms of generated substances and low adsorption, and in addition, considering the configuration, structure, manufacturing method, etc., changes over time inside the bag body It is necessary to make the device as small as possible to achieve the highest measurement accuracy and high evaluation and reliability.

  For example, as shown in FIGS. 6A and 6B, the inner and outer double film structure of the container is used, and the same sampling gas is filled in both the inner bag and the outer bag, so that the gas composition in the inner bag is changed. There has been proposed a gas sample collection container that is practically invariant and extremely reduces errors (see, for example, Patent Document 1). Specifically, when the gas sample is collected, the valve on the outlet side is closed and the valve (110) and the valve (111) are opened in the inner bag (104) and the outer bag (105) to be filled with the same sample gas. . Thereafter, the valves (110) and (111) may be closed and taken home as they are. The gas composition in the outer bag (105) changes very little by the gas permeability of the film, but the gas composition in the inner bag (104) is hardly affected. For example, a plastic material may be used for the film bag. Here, (103) is an inner / outer double film bag, (106) is a gas inlet pipe to the outer bag (105), (107) is a gas inlet pipe to the inner bag (104), (108), (109 ) Indicates a gas outlet pipe, and (112) and (113) indicate valves.

Japanese Utility Model Publication No. 61-125743

  However, the following problems and problems may occur in the gas sampling bag as described above.

(I) Recently, high measurement accuracy is required in the measurement and analysis as described above, and high stability is also required for the gas collected in the bag corresponding to this. However, the actual situation is that the construction of a bag body that can actually meet such demands has not been achieved. Specifically, for gas sampling bags,
(A) There is no permeation of the collected gas to the outside (there will be a change in composition if some of the components are also permeable),
(B) There is no or very little reactivity with the sampled gas inside the bag body,
(C) There is no or very little gas generation from the bag itself,
(D) The sampled gas is not denatured or very little by ultraviolet rays or heat rays from the outside of the bag body,
(E) The characteristics (a) to (d) described above are required to be maintained for a predetermined period after the gas is collected and the measurement and analysis are completed.

  (Ii) In the invention according to the above-mentioned Patent Document 1, there is only a description that “the film bag should be made of a plastic material,” for example, and particularly gas sampling used for measurement of odor or measurement of components in a sample gas. Sufficient conditions that can be used as a bag body are not disclosed. Moreover, in the said structure, since the gas collection volume required for a measurement becomes smaller than the gas volume in an outer bag, a bigger bag is required. This enlarges the suction surface, doubles the material film and parts, and causes complicated processing, further increasing the cost burden. The same applies to materials and structures in other prior arts, and it has been difficult to use as a gas sampling bag.

  (Iii) In general, from the viewpoints of the above (a) to (c), the bag body itself is preferably a polyester film excellent in heat resistance and chemical resistance, such as a polyethylene terephthalate (hereinafter referred to as “PET”) film. However, from the viewpoint of (d), it is indispensable to shield ultraviolet rays from the outside. At this time, for example, it is conceivable to use a polyethylene terephthalate (hereinafter referred to as “aluminum PET”) film deposited on aluminum or the like. Conventionally, there is no appropriate method other than the bonding of a film using an adhesive, and the above characteristics (a) to (c) are secured by the influence of reactivity with the adhesive or impurities generated from the adhesive. It was difficult.

  (Iv) On the other hand, a bag made of fluorine resin or the like having high corrosion resistance has a very high gas permeability, and therefore, a gas sampling bag used for measurement of odor or storage of components in a sample gas that requires long-term storage. It is not suitable for use as a body. Moreover, fluororesin films such as FEP and PVDF that are partially used as gas sampling bags are very expensive and difficult to use as general gas sampling bags. In addition, the soft and high melting point characteristics of these materials are difficult to make bags.

  (V) The polyester film has various grades depending on its composition and production method. In the verification of the present inventors, a high-purity polyester film is preferable in order to satisfy the above characteristics (a) to (c). A biaxially stretched polyester film with high density is applicable, but the film with the highest density and high purity is preferable among them. On the other hand, a light-shielding material such as aluminum is deposited on the surface of the film. And found it difficult to fix. That is, it was very difficult to construct a gas sampling bag that satisfies the above (a) to (e).

  Therefore, the object of the present invention is to provide a high sealing property without any special treatment or processing in the measurement of odor or the measurement of components in the sample gas, without any deterioration of the filled gas, and from the outside. An object of the present invention is to provide a gas sampling bag that can block ultraviolet rays, heat rays, and the like, and a method for manufacturing the same.

  As a result of intensive studies, the present inventors have found that the above object can be achieved by the gas sampling bag and its manufacturing method described below, and have completed the present invention.

The gas sampling bag according to the present invention has a non-gas-permeable and non-gas-adsorbing density of 1.40 g / cm ³ or more and a high-density high-purity polyester film having a purity of 98% or more, and a light shielding function. Yes and, while being constituted by a plurality of polyester film comprising an outer layer of polyester film of low density and low purity of the inner layer and the same material and different, have been fabricated superimposed layers of the same material of the inner layer and the outer layer The end portion of the sheet is heat-sealed by a heat-sealing process to form a sealed structure.

Further, the present invention is non-gas permeable, non-gas absorptive density 1.40 g / cm ³ or more, and an inner layer made of a polyester film of 98% purity or more high density high purity, have a light shielding function, the inner layer A method for producing a bag comprising a plurality of polyester films comprising the same material and different layers of low-density low-purity polyester films, comprising the following steps:
(1) A step of producing a sheet by superimposing the inner layer and the outer layer (2) A step of folding the sheets or overlapping a plurality of sheets to match edges (3) An end of the sheet on which layers of the same material are superimposed (4) a cutter that can run parallel to the clamp, or an end of the sheet that can run parallel to the cutter. A step of cutting the portion (5) a step of heat-sealing the end portion of the sheet by heat-sealing treatment to produce a sealed bag body (6) a notch portion on the end portion or the sheet surface of the sheet And providing a gas intake / exhaust port having a light-shielding property (7) a step of performing a sealing process of the notch,
When a heat seal bonding process at a plurality of locations is required, a sealed bag body is manufactured by repeating steps (3) to (5).

It is necessary to satisfy the characteristics (a) to (e) at the same time in the gas sampling bag body that can meet the recent high demands. In the verification process, the inventor is difficult to satisfy the characteristics (a) to (e) simultaneously with one film, and the characteristics (a) to (c) and (d) are This can be ensured by using a non-gas-permeable and non-gas-adsorbing density of 1.40 g / cm ³ or more and a high-density, high-purity polyester film with a purity of 98% or more in the portion (inner layer) in direct contact with the sample gas. The characteristics (d) and (e) can be ensured by using a low-density low-purity polyester film having a light-shielding function as an outer layer, and the end portion of the sheet on which these are laminated is sealed by heat-sealing It has been found that it is possible to satisfy the characteristics (a) to (e) at the same time by performing the above. At this time, by making the material constituting the inner layer and outer layer common to the chemical and physical properties of polyester, it is possible to achieve a firm seal structure that effectively utilizes heat fusion treatment for the same material and different polyester films In addition, by such a configuration or manufacturing method, a gas sampling bag body that has an unprecedented high sealing property, does not deteriorate the filled gas, and can block ultraviolet rays and heat rays from the outside, and The manufacturing method can be provided.

As used herein, “high density and high purity” refers to a film having the smallest characteristics of gas permeability, gas adsorption, and gas release due to pores and penetration. Specifically, currently usable PET films are based on a density of 1.40 g / cm ³ or more and a purity of 98% or more, but each type is improved in plastic within a range of 0 to 2% purity. It is guessed. A “high-density high-purity film” refers to a film that has a small degree of improvement and is at a position closest to 100% purity. Other film types and other types of polyester film groups are referred to as “low density and low purity films”.

The present invention is the above-described gas sampling bag, the outer layer, which has a vapor-deposited layer of aluminum on at least one side of a polyester film as a base material, is configured as the vapor deposition layer is the outermost, heat In the fusion treatment, a curl shape on the base material side of the vapor deposition layer is formed from the difference in thermal shrinkage between the base material and the vapor deposition layer, and the sealing property between the vapor deposition layers is ensured . Moreover, this invention is a manufacturing method of the said bag body for gas sampling, Comprising: In the said process (1), (5), the said outer layer has a vapor deposition layer of aluminum in the at least single side | surface of the polyester film used as a base material. In addition, the vapor deposition layer is configured to be the outermost side, and in the thermal fusion treatment, a curl shape on the base material side of the vapor deposition layer is formed from the difference in thermal shrinkage between the base material and the vapor deposition layer. The sealing property is ensured.

  As described above, the gas sampling bag according to the present invention can ensure high sealing performance without impairing the functions of the gas contacting film and the light shielding film without performing special treatment or processing. One of the important issues. In the present invention, a polyester film having an aluminum vapor deposition layer on one side is used as an outer layer, and the end portion of the sheet on which these layers are laminated is subjected to a sealing process by heat fusion, as described in the above (a) to (e). It is possible to satisfy various properties at the same time, and by heat-sealing the end portion formed by folding or stacking a plurality of sheets so that the deposited layer becomes the outermost surface, It has been found that a curl shape in the direction can be formed (details will be described later), and the sealing property between the vapor deposition layers can be secured.

  The present invention is the gas sampling bag, wherein the outer layer is made of a polyester film containing a reagent having a light shielding function.

  As described above, the gas sampling bag according to the present invention is a solid material that effectively utilizes the heat-sealing process by making the material constituting the inner layer and the outer layer the same chemical and physical properties of polyester. A seal structure is possible. In the present invention, by using a polyester film containing a reagent having a light-shielding function as an outer layer, it is possible to satisfy the characteristics (a) to (e) at the same time without performing special treatment or processing. Thus, it has become possible to construct a gas sampling bag body that blocks ultraviolet rays and heat rays from the outside, has an unprecedented high sealing property, and does not denature the filled gas.

  The present invention is the gas sampling bag, wherein the polyester film constituting the inner layer is made of high-density high-purity polyethylene terephthalate, and the polyester film constituting the outer layer is lower in density and lower purity. It consists of polyethylene terephthalate.

The present invention is a method for producing the gas sampling bag, wherein in the step (1), a high-density high-purity polyethylene terephthalate film constituting an inner layer and a low-density low-purity polyethylene terephthalate film constituting an outer layer are provided. The film is continuously fed from the rolls wound so that the winding direction and the axial direction with a high stretch ratio of each film are the same, and the sheet is produced, and the heat-seal bonding treatment to the end of each film Is performed in the same direction as the axial direction with a high stretch ratio .

As a result of repeated detailed verification of the characteristics (a) to (e) required for the gas sampling bag, the inner layer is a high-density high-purity polyethylene terephthalate (hereinafter referred to as “S-PET”) film. The outer layer is preferably a PET film (hereinafter referred to as “light-shielding PET film”) made of low-density low-purity polyethylene terephthalate (hereinafter referred to as “PET”) as a raw material and containing a light reflection layer on at least one surface or a reagent having a light-shielding function in the layer. ")" Was found to be suitable. In other words, in general, PET film has excellent properties such as mechanical strength, chemical resistance, moisture / water resistance, transparency, and plasticizer, but S-PET film is more odorless, transparent, and gas permeable. It has been verified in a demonstration test that it has excellent properties such as low adsorptivity and low adsorptivity and low volatile substances, and is very suitable for the inner layer of the bag according to the present invention. Moreover, also in the sealing method, it was verified that the combination with the light shielding PET film was suitable. In other words, the light-shielding PET film has the function of shielding and reducing ultraviolet rays and heat rays as in the above (d) and (e), and suppresses the progress of photochemical reaction and carbon monoxide (CO) generated from the PET film. In addition, it is possible to obtain a strong seal that is highly fusible with the S-PET film during the heat fusing process. Therefore, by combining such films, a gas sampling bag body that has an unprecedented high sealing property, does not deteriorate the filled gas, and can block ultraviolet rays and heat rays from the outside, and its manufacture It became possible to provide a method. Here, the winding direction of the raw fabric roll and the axial direction where the stretching ratio of each film is high are the same, and by performing the heat seal adhesion treatment on the end of each film in the same direction as the axial direction where the stretching ratio is high, Stable melting at the end of the film can be generated, and uniform and reliable melt bonding can be performed.

  The present invention is the gas sampling bag, wherein at least a part of the outer layer further has a coating layer made of an epoxy resin.

  Further, the present invention is the above method for producing a gas sampling bag, wherein in at least a part of the bag in the subsequent step of the step (4), (5) or (7), The coating process with an epoxy resin is performed under conditions of 130 to 140 ° C.

  The gas sampling bag is composed of the bag itself and a gas intake / exhaust port for injecting the sample gas into the bag, and the bonding / sealing process between the gas intake / exhaust port and the bag is based on the sealing performance of the gas sampling bag as a whole. Play an important role. In particular, it is necessary to ensure a sufficient sealing property even by freely operating the gas intake / exhaust port around the joint with the bag body at the time of sampling or measurement of the sample gas. At this time, by covering the outer surface of the bag body around the joint, a double sealing process is performed, and higher sealing performance can be secured. In addition, since the gas sampling bag according to the present invention is provided with a vapor deposition layer on the outermost side thereof, by performing a coating treatment on the outer layer, the gas sampling bag body also has a protective function of the vapor deposition layer. It becomes possible to maintain the characteristic of e) for a long time.

  The present invention is a method of manufacturing the gas sampling bag, wherein when the sheet is folded back in the step (2), the bulging portion generated at the folded portion or both ends of the folded side is super It is characterized by performing a point seal process using sound waves.

  In the manufacturing process of the gas sampling bag, the end portion where the plurality of films are stacked is sealed. At this time, for example, when a bag is formed by folding one sheet on which two films are overlapped, a bulging portion is generated at both ends of the folded portion or the folded side. When the end portion is heat-bonded in this state, there is a risk that the swelled portion may have a gap in film overlap or an insufficient heat-conducting portion. May occur. The present invention eliminates such a possibility by performing a point seal process using ultrasonic waves in advance, and makes it possible to ensure a reliable seal process for the folded part or both ends of the folded side. In addition, by setting the point seal within the range in which the heat seal of the subsequent process reaches, formation of a seal portion in the minimum range and a uniform high level heat seal are ensured.

  This invention is a manufacturing method of the said bag for gas sampling, Comprising: In the said process (5), the temperature of the said edge part heated by the said heating part exists in the melting temperature area | region of a polyester film, While providing a space | gap between the end surface of the said sheet | seat and a heating part, maintaining this space | gap distance, the said clamp or / and a heating part are run, and this edge part is fuse | melted and integrated gradually, It is characterized by the above-mentioned.

  It is very difficult to perform a uniform and reliable heat-sealing process on the ends of the overlapping resin layers. In particular, in the manufacturing process of the gas sampling bag according to the present invention, four or more resin layers overlap, and the outermost layer has an aluminum vapor deposition layer with high thermal conductivity. It has been further difficult to perform a heat-sealing process that ensures sealing performance. The present invention provides a predetermined gap between the end face of the sheet and the heating part in the heat sealing process, and while the gap distance is maintained, the clamp or / and the heating part are run to gradually melt the end part. By integrating them, it was possible to perform a uniform and reliable heat fusion treatment. Here, the predetermined gap distance means a distance that is set so that the temperature of the end portion is within the melting temperature region of the polyester film, and the temperature of the heater according to the shape and length of the end portion. Adjusted.

  The present invention is the method for manufacturing the gas sampling bag, wherein in the steps (4) and (5), the traveling speed of the clamp or / and the heating unit is determined by the thermal contraction speed or heating and melting of the sheet. It is characterized by having a speed that is substantially equal to or not exceeding the contraction speed.

  As described above, the gap distance between the heat-bonded portion and the heating portion is an important index for the end portions of the overlapping resin layers. The present inventor has found that in the verification process, the heat shrinkage rate or the shrinkage rate due to heating and melting is important, and by controlling this using the traveling speed of the clamp or / and the heating part as an index, It has become possible to perform a more uniform and reliable heat-sealing treatment.

  As described above, according to the present invention, there is no special treatment or processing, high sealing performance, no deterioration of the filled gas, and it is possible to block ultraviolet rays and heat rays from the outside. It has become possible to provide a gas sampling bag and a method of manufacturing the same.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<Gas Sampling Bag according to the Present Invention>
The gas sampling bag according to the present invention (hereinafter referred to as “the present bag”) includes a non-gas permeable and non-gas adsorbing high-density high-purity polyester film, and a low-density low-purity having a light shielding function. It is composed of a plurality of polyester films including an outer layer made of polyester film, and the end of the sheet produced by superimposing the inner layer and the outer layer is heat-sealed by a heat-sealing process to form a sealed structure It is characterized by doing.

  Here, “polyester” is a general term for polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN) and polybutylene naphthalate (PBN). Among these films, high-purity polyester films not only have excellent non-gas permeability from the pores for gases such as hydrogen, but also have minimal permeability to water and high-boiling hydrocarbons. In addition, it refers to a film having excellent properties and excellent non-gas adsorption properties for these gases. Specifically, the type (S-PET) selected by a strict comparative test from the type group of biaxially stretched polyethylene terephthalate (PET) film is applicable. Here, the other films are referred to as “low density and low purity films”. The “light-blocking function” refers to a function that reflects or absorbs infrared rays, visible light, ultraviolet rays, etc. irradiated on one side of the film and does not transmit the other side.

Currently available films are based on a density of 1.40 g / cm ³ or more and a purity of 98% or more, and have various types according to the application. For the high-density and high-purity polyester film in the present invention, the optimum type is selected from these type groups. The non-gas permeable, non-gas adsorbing or non-gas releasing properties mentioned here are not intended to require each characteristic generated in long-term use exceeding several months to be in a minute range, but are required as a bag for gas sampling. A film having a function capable of maintaining each characteristic in use for several days or at most several weeks is defined with the aging of 0 to 24 hours being the most important. In the verification process, since these types of PET films are excellent in transparency, smoothness, and gloss, it is preferable to use these characteristics as selection criteria in the selection of the “high density and high purity film”. Furthermore, the most suitable film for the gas sampling bag is selected by comparing the odor of odorless air over time using an olfactory sensor or odor sensor, and comparing the measured values over time using a component measuring device such as VOC. In the verification process, it became clear that the amount of NMHC (non-methane hydrocarbon) was the main cause of odor. Therefore, as will be described later, for example, NMHC in TVOC (total VOC) is measured by the FID method, and a high-density and high-purity polyester film can be selected based on the aging characteristics.

[One aspect of implementation of the bag (first configuration example)]
1A and 1B show, as a first structural example of the present bag body, an inner layer 1 made of a non-gas-permeable and non-gas-adsorbing high-density high-purity polyester film, and an aluminum deposited layer on one side. And a plurality of polyester films including an outer layer 2 made of a low-density low-purity polyester film having 3 and a vapor-deposited layer 3 that is the outermost layer, and the inner layer 1 and the outer layer 2 are overlapped. The end part 4 (4a-4d) of the made sheet | seat is heat-seal-bonded by the heat-fusion process, and the bag body which forms a sealing structure is shown. A gas intake / exhaust port 6 that communicates with the space 5 formed by the inner layer 1 is provided at one end 4d of the bag body. Hereinafter, the case where “PET” is used as the polyester film will be described unless otherwise specified.

  The collected sample gas is introduced into the space portion 5 through the intake / exhaust port 6, and the inner layer 1 having non-gas permeability and non-gas adsorption property maintains a state in which there is no alteration or leakage and no composition change occurs. can do. That is, it is possible to eliminate unstable elements inside the bag body with respect to the sample gas. At the same time, the light irradiated from the outside is reflected by the aluminum deposition layer 3 provided in the outermost layer, passes through the space portion 5 and undergoes a photoreaction of the components in the sample gas, particularly alteration by ultraviolet rays. Can be prevented. That is, unstable elements from the outside of the bag body with respect to the sample gas can be eliminated. Thus, this bag body can ensure the high stability with respect to the sealed sample gas.

  In addition, for long-term stability to the sample gas, in addition to eliminating unstable elements from the gas contact part or from the outside, the inner layer 1 and the outer layer 2 are made of the same material (PET), and heat fusion treatment is performed. By using and heat-sealing the joint portion, a very excellent sealing property can be secured. Furthermore, since the outer layer 2 having the outermost layer as the vapor deposition layer 3 is formed of an aluminum PET film, a “curl shape” to be described later can be formed between the vapor deposition layers 3 that overlap each other. Also in the sealing function, a fine ventilation shielding function can be secured.

  Here, the inner layer 1 is preferably formed of S-PET because of its non-gas-permeable and non-gas-adsorbing height. PET film has excellent properties such as mechanical strength, chemical resistance, moisture / water resistance, transparency, and plasticizer, but S-PET film is more odorless, transparent, gas permeable and adsorption. It has excellent characteristics such as low properties and low volatile substances, and is suitable for the inner layer 1 of the bag.

  The outer layer 2 is preferably a low-density, low-purity polyethylene terephthalate (hereinafter referred to as “aluminum PET”) film having an aluminum deposition layer 3 on one side as a light-shielding PET film. By utilizing the strong adhesion property between low density and low purity PET and aluminum, the strong aluminum vapor deposition layer 3 can be formed on the outermost layer of the outer layer 2. In addition, the aluminum PET film has a function of shielding and relaxing ultraviolet rays and heat rays, and can obtain the effect of suppressing the progress of photochemical reaction and carbon monoxide (CO) generated from the PET film. It is possible to form a strong seal with high fusion with the S-PET film during the adhesion treatment.

  In addition, the outer layer 2 can also use the woven fabric of a black polyester fiber, and a black polyester nonwoven fabric as a light shielding PET film. While having the function of light-shielding and mitigating ultraviolet rays and heat rays, it is possible to integrally weld and to form a highly sealed bag body by heat sealing described later.

  Moreover, when forming a bag body, as shown in FIG. 1A, after stacking a plurality of films including the inner layer 1 and the outer layer 2, the end portions 4a to 4d are not heat-sealed. Two sheets are stacked so that the film surface of the aluminum PET film is in contact with the S-PET film (the same applies to two or more sheets), and the S-PET film is folded in two so that the S-PET film is on the inside. preferable. As shown in FIG. 1 (C), the end 4b 'is folded in half, so that the heat-sealed portion is reduced and the sealing property is secured, and the light shielding property is secured by ensuring the continuity of the outermost layer. can do. At this time, as shown in FIG. 1 (D), in order to ensure the heat-sealing process of the end portions 4a and 4c, the folded end portion 4b ′ or the bulging portions generated at both end portions 4ab ′ and 4bc ′ On the other hand, as will be described later, it is preferable to perform a point seal process using ultrasonic waves in advance.

  The bag body includes a bag body itself and a gas intake / exhaust port 6 for injecting gas into the bag body, and the gas intake / exhaust port 6 preferably has a metal gas intake / exhaust port. The gas intake / exhaust port 6 is also required to have substantially the same functions as the above (a) to (e), and is accompanied by operations such as sealing of the joint with the bag and connection with other parts in the sampling operation. Robustness is required. Conventionally, a glass tube or a resin was sometimes used, but since it was difficult to block ultraviolet rays or the like, the stability of the sampled gas in the bag could be affected. It is difficult to secure the glass tube firmly to the bag body and ensure high sealing performance, especially when ensuring high workability and sealing performance for a film having the vapor-deposited layer 3 of light shielding material such as aluminum PET. Are better.

[Other Embodiments of the Bag (Second Configuration Example)]
FIG. 1E shows a polyester film containing a reagent having a light-shielding function in place of the outer layer 2 made of a low-density, low-purity polyester film having the aluminum vapor-deposited layer 3 as a second structural example of the bag body. In the case of using PET as a material, a bag body using an outer layer 2a made of a light shielding PET film) is shown. Examples of the reagent having a light shielding function include fine particles and fine particles such as carbon black and titanium oxide. The film itself forming the outer layer 2a can have a light shielding function, and the strength of the light shielding function can be adjusted by a plurality of light shielding PET films. Moreover, the heat sealing | fusion process of the sheet | seat produced by superimposing the inner layer 1 and the outer layer 2a can also be performed easily, and the bag body which has a structure with a high sealing degree can be produced.

<Method for manufacturing the bag>
The method for producing a gas sampling bag in the present invention (hereinafter referred to as “the present production method”) includes the following steps:
(1) A step of superposing an inner layer and an outer layer to produce a sheet (2) A step of folding the sheets or stacking a plurality of sheets to match the edges (3) The end of the superimposed sheets is clamped (4) cutting the edge of the sheet with a cutter that can run parallel to the clamp, or a clamp that can run parallel to the cutter (5) (6) A gas intake / exhaust port having a light shielding property by providing a notch on the end of the sheet or on the sheet surface. (7) In addition to the step of sealing the notch, the steps (3) to (5) are repeated to perform heat seal bonding at a plurality of locations to produce a sealed structure bag body To do.

[Verification results for heat fusion treatment of PET film]
Prior to the production of the bag, the PET film, the S-PET film, and the aluminum PET film were examined for the state of the melt-bonded portion of the film or the change in the film shape when the heat-sealing treatment was performed. Obtained knowledge.
(A) The melt-bonded portion of the PET film and the S-PET film has a round shape or a rod shape, and has a strong adhesive force.
(A) In the PET film and the S-PET film, the fusion in the stretched vertical axis direction is extremely stable in melting, but the horizontal axis direction exhibits a slight wave shape in the stage of heat shrinkage to melting, so that the melt-bonded portion is unstable. It becomes a factor. Presumed to be caused by the difference in the stretch ratio between the vertical axis and the horizontal axis.
(C) The melt-bonded portion of the aluminum PET film has a flat shape.
(D) The width of the hot melt shrinkage of the aluminum PET film is smaller than that of the PET film, and the strength is about 1/3 that of the PET film, but it is excellent in uniformity.
(E) The aluminum PET film curls to the PET side due to the difference in thermal shrinkage between the base PET and the deposited layer. This becomes the adhesive force between the two films and causes uniformity.
(F) Since the heat fusion unit heating amount of the aluminum PET film is smaller than the heat fusion unit heating amount of the PET film having the same thickness, the thermal deterioration of the aluminum PET film is small.

  As a result of examining the manufacturing method of this bag body based on such knowledge, it turned out that the following manufacturing processes are optimal. Hereinafter, when there is no particular limitation, the case where “PET” is used as the polyester film will be described with reference to FIGS.

(1) Step of superposing the inner layer and the outer layer to produce a sheet As shown in FIG. 2 (A), the inner layer 1 and the outer layer 2 are continuously supplied from the raw rolls R1 and R2, and the two are stacked. Together, the sheet S is produced. At this time, when the outer layer 2 is composed of an aluminum PET film having the vapor deposition layer 3 on one side, the vapor deposition layer 3 is the outermost layer (the PET film is in contact with the S-PET film constituting the inner layer 1). It is preferable to superimpose. While preventing deterioration of the filled gas, it is possible to form a strong seal S that has a high fusion property with the S-PET film during the heat fusion treatment. At this time, as for original fabric roll R1, R2, it is preferable that the winding direction and the axial direction with a high stretch ratio of PET film are the same. By performing the heat seal bonding treatment on the end portions 4a and 4c shown in FIG. 1 (A) in the same direction as the axial direction having a high stretch ratio as shown in the above finding (A), the end portions 4a and 4c of the PET film Stable melting and uniform and reliable melting and bonding can be performed.

  In addition, when one or two (multiple) PET films (or S-PET films) are placed between two superposed aluminum PET films to form a multi-layer and heat-sealed, aluminum PET The curling force to the PET film side of the film is transmitted from the top and bottom to the PET film, the instability factors such as the above knowledge (A) of the PET film are alleviated, and the heating time is shortened to almost the same as the aluminum PET film. Adhesive strength can be obtained.

(2) Step of folding the sheet or stacking a plurality of sheets and aligning the end portions As illustrated in FIG. 2B, the sheet S is cut into a regular length by a cutter K, and as shown in FIG. A plurality of sheets S1, S2 are overlapped to align the end portions 41, 42. FIG. 2D illustrates a case where the regular sheets S are folded and overlapped. At this time, in the case where the outer layer (21, 22, 2) is composed of an aluminum PET film having a vapor deposition layer (31, 32, 3) on one side, the vapor deposition layer (31, 32, 3) is the outermost layer. It is preferable to overlap. While preventing deterioration of the filled gas, it is possible to form a strong seal with high fusion with the S-PET film during the heat fusion treatment.

(3) Step of clamping the end portion of the overlapped sheet with a clamp by leaving a portion related to the heat-sealing process As shown in FIG. 3A, a processing part 4h for performing the heat-sealing process In addition, the end portion 4 of the overlapped sheet S is sandwiched between the clamps P1 and P2 with the cut processing portion 4e remaining. At this time, when the sheet S is folded back, as illustrated in FIG. 3B, the bulging portion generated at the folded end portion 4b ′ or its both end portions 4ab ′ and 4bc ′ (in this step, the processing portion is further processed). 4h and the cut processing portion 4e), it is preferable to perform point seal processing PS by ultrasonic waves in advance. It is possible to use a method of partial sealing or a method of sealing with a hot melt adhesive in a later process, but by performing point sealing before sealing, the end 4b ′ including the bulging portion can be securely The film S can be held evenly, and the film S can be prevented from misalignment or insufficient heat conduction, and a reliable heat-sealing treatment can be performed to the end portions 4a and 4c and both end portions 4ab 'and 4bc'. Reliable sealing process can be ensured. In particular, since both end portions 4ab ′ and 4bc ′ are likely to have unsealed portions, it is preferable to perform preliminary sealing by point sealing processing using ultrasonic waves several millimeters in advance and then perform full length sealing. Moreover, it is preferable that the point seal is within a range in which the heat seal melts in the subsequent step (5). Thereby, the seal part in the bag body after molding can be made the minimum range, and the total seal length can be made uniform at the heat seal level in the subsequent process.

(4) Cutting the edge of the sheet with a cutter that can run in parallel with the clamp, or a clamp that can run in parallel with the cutter. As shown in FIG. 3C, the edge of the sheet S. Cut processing portion 4e is cut by cutters K1 and K2 (corresponding to blades). At this time, as illustrated in FIG. 3D, by moving the cutters K1 and K2 in parallel with the clamps P1 and P2, a uniform cut surface can be formed with respect to the cut processing portion 4e. Further, the same processing can be performed by fixing the cutters K1 and K2 and running the clamps P1 and P2 in parallel with the cutters K1 and K2.

(5) Step of heat-sealing the end of the sheet by heat-sealing treatment to produce a sealed bag body As shown in FIG. The PET film (inner layer 1 and outer layer 2) is heat-sealed by heat-sealing treatment, and a sealed bag body is produced. As illustrated in FIG. 3 (F), the heating part H is allowed to travel in parallel with the clamps P1 and P2, so that an equal heat fusion process can be performed on the processing part 4h. At this time, it is preferable that the traveling speed of the heating unit H is set to a speed substantially equal to or not exceeding the thermal shrinkage speed of the sheet S or the shrinkage speed due to heating and melting. For the end of the overlapping resin layer, the gap distance between the processing portion 4h and the heating portion H is an important index. By controlling the traveling speed of the heating portion H using this as an index, uniform and reliable heat fusion is achieved. It became possible to perform the arrival processing. The same processing can be performed by fixing the heating unit H and running the clamps P1 and P2 in parallel with the heating unit H.

  In addition, since it is very difficult to perform uniform and reliable heat fusion treatment on the end portions of the overlapping resin layers, the temperature of the treatment portion 4h heated by the heating portion H is the melting temperature of the PET film. It is preferable to provide a gap between the processing portion 4h and the heating portion H so as to be within the region, and to gradually melt and integrate the processing portion 4h by running the heating portion H while maintaining the gap distance. . In this manufacturing method, four or more films are overlapped, and an aluminum vapor deposition layer having a high thermal conductivity is provided on the outermost side, which is a particularly effective means. The predetermined gap distance here refers to a distance that is set so that the temperature of the processing portion 4h is within the melting temperature region of PET, and the heating portion H of the heating portion H depends on the shape and length of the processing portion 4h. Adjusted with temperature.

  The above step (5) is performed at the same time as the step (4), and a thermal fusion treatment is immediately performed on a new cut surface, thereby preventing the deviation of the polymerization of the film S and a reliable thermal fusion treatment. It can be performed.

(6) Step of providing a notch portion on the end or sheet surface of the sheet and providing a gas intake / exhaust port having light shielding properties The gas intake / exhaust port 6 provided in the bag body is formed from the workability shown in FIG. As shown in A) and (B), the metal gas inlet / outlet 6 is disposed at the end 4d of the sheet S, or at both ends 4ad or 4cd thereof. However, the arrangement position of the gas intake / exhaust port 6 is not limited to this, and can be on the surface of the sheet S. Further, the gas intake / exhaust port 6 is preferably a corrosion-resistant tubular body such as a metal such as stainless steel because of the sealing performance of the joint portion with the polyester film and the robustness accompanied by operations such as connection with other parts in the sampling operation. The notch 6a is cut along the end 4d or both ends 4ad or 4cd to a size that allows the gas intake / exhaust port 6 to be inserted with some flexibility using a knife or the like.

(7) Step of sealing the notch 6 In the sealing process of the notch 6a, the gas inlet / outlet contacting the inner peripheral surface of the notch 6a before inserting the gas inlet / outlet 6 into the notch 6a. A thermoplastic resin adhesive 6 b is applied to the outer peripheral surface of 6 in advance. Although the adhesive 6b is not specified, for example, an epoxy resin that cures at room temperature is preferable. As shown in FIGS. 4A and 4B, after a layer of adhesive 6b is formed on the outer peripheral surface of the gas intake / exhaust port 6, the gas intake / exhaust port 6 is inserted in a direction perpendicular to the notch 6a, The adhesive 6b application portion of the intake / exhaust port 6 is attached to the inner peripheral surface of the notch 6a, and the inner peripheral surface of the notch 6a and the outer peripheral surface of the gas intake / exhaust port 6 are completely intimately sealed. At this time, as shown in FIG. 4A, by decentering the gas intake / exhaust port 6, the area of the inner peripheral surface of the notch 6a contacting the outer periphery of the gas intake / exhaust port 6 can be increased, and the notch 6a. Securely contacts the outer peripheral surface of the gas inlet / outlet 6. By maintaining this state for a predetermined time, the notch 6a and the gas intake / exhaust port 6 are securely bonded.

  (8) In the above, one cycle of the sealing process is completed. However, when a plurality of heat seal bonding processes are required, the steps (3) to (5) are repeated, so that the sealing structure A bag can be produced. Specifically, when a plurality of sheets S are overlapped, the processing is performed for the end portions 4a to 4d, and when the sheet S is folded, the processing is performed for the end portions 4a, 4c, and 4d.

  At this time, it is preferable that at least a part of the bag body is subjected to a coating treatment with an epoxy resin at a temperature condition of 130 to 140 ° C. in any subsequent step of steps (4), (5) or (7). . By coating the outer surface of the bag body around the joint, a double sealing process is performed, and higher sealing performance can be secured. Further, when an aluminum PET film is used for the outer layer 2, it is possible to have a protective function for the vapor deposition layer 3 provided on the outermost side.

  The actual sample gas was used as a target, and a demonstration experiment including comparison with a conventional gas sampling bag was performed using this bag.

[Example 1]
(1) Experimental bag body Experiments were conducted on the bag bodies Fa to Fe shown in Table 1 below. Bag body Fa is a PET film (manufactured by Toray Industries, Inc., model Lumirror (TM)), bag body Fb is a fluororesin (FEP) film (manufactured by Daikin, Neoflon (TM)), and bag body Fc is a polyvinyl fluoride resin (PVF) A film (manufactured by DuPont, Tedlar (TM)) was used. A bag formed using an S-PET film (manufactured by Toray Industries, Inc., model Lumirror (TM)) as an inner layer and an aluminum PET film (manufactured by Toray Industries, Inc., model Lumirror (TM)) as an outer layer as the main bags Fd and Fe. Was used. The internal volume of each bag was 20L.

(2) Experimental gas The air sampled at one point in Kyoto city was used as a sample gas, and its change with time was traced.

（３−３）測定装置
ＣＨ_４、ＮＭＨＣおよびＴＨＣについては、大気汚染監視用ＨＣ濃度測定装置（堀場製作所社製、ＡＰＨＡ−３７０）を用いて測定し、ＣＯについては毒ガス検知器（一酸化炭素計）（新コスモス電機社製、ＸＣ−２２００）を用いて測定した。 (3) Experimental conditions (3-1) Measurement items The concentrations of methane (CH ₄ ), NMHC, total hydrocarbons (THC), and carbon monoxide (CO) in the sample gas at an elapsed time of 0 to 75 hours including the middle. It was measured.
(3-2) Exposure conditions The bags Fa to Fe were exposed under the conditions shown in Table 2 below. In the case of indoors, the room temperature was set to 18 to 25 ° C., and in the case of the outdoors, the environmental temperature was 7 to 22 ° C. (there was a temperature rise accompanying sunlight irradiation).

(3-3) Measuring device CH ₄ , NMHC and THC are measured using an HC concentration measuring device for air pollution monitoring (APHA-370, manufactured by Horiba, Ltd.), and a poisonous gas detector (carbon monoxide) is measured for CO. Total) (New Cosmos Electric Co., Ltd., XC-2200).

(4) Results Results as shown in FIGS. 5 (A) to (D) were obtained.
(4-1) CH ₄
As shown in FIG. 5 (A), the variation of CH ₄ was large in the PVF film (Fc), and was slightly higher at each time point of the FEP film (Fb). The other films including the bag were all the same, although there were some fluctuations.
(4-2) NMHC
As shown in FIG. 5 (B), the fluctuation of NMHC was large in the PVF film (Fc), and the value was slightly higher in the PET film (Fa). The other films including the bag were all the same, although there were some fluctuations.
(4-3) THC
As shown in FIG. 5 (C), the variation of THC was large in the PVF film (Fc), and a tendency to gradually increase in the PET film (Fa) was observed. There was almost no change in all the other films including the bag.
(4-4) CO
As shown in FIG. 5D, the PET film (Fa) showed a tendency to gradually increase. There was no change in the bag (Fe).

(5) Summary As described above, the conventional PET film (Fa), FEP film (Fb), and PVF film (Fc) do not have a light-shielding function, and are variable factors in any of the above measurement items. As a result, On the other hand, in this bag body, such a tendency was not seen at all, it was proved that there was no deterioration of the filled gas, and the function of blocking ultraviolet rays and heat rays from the outside was sufficient.

  The gas sampling bag described above has mainly been described for a bag used for odor measurement with excellent sample gas stability. However, the bag is not limited to such applications, and various process gases are used. It can be widely applied to the field of collecting air, air, exhaust gas, etc., especially on-site and measuring in batch.

Explanatory drawing which illustrates the structure of the bag body for gas sampling which concerns on this invention Explanatory drawing which illustrates the manufacturing process of the bag body for gas sampling which concerns on this invention Explanatory drawing which illustrates the manufacturing process of the bag body for gas sampling which concerns on this invention Explanatory drawing which illustrates the manufacturing process of the bag body for gas sampling which concerns on this invention Explanatory drawing illustrating the verification test results of the gas sampling bag Explanatory drawing which shows the bag body for gas sampling which concerns on a prior art

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, Inner layer 2, 21, 22 Outer layer 3, 31, 32 Deposition layer 4, 4a, 4b, 4b ', 4c, 4d, 4ab', 4bc ', 41, 42 End 4e Cut processing part 4h Processing part 5 Space part 6 Gas inlet / outlet 6a Notch 6b Adhesive K, K1, K2 Cutter (blade)
H Heating part P, P1, P2 Clamp PS Point seal processing R1, R2 Original fabric roller S, S1, S2 Sheet

Claims (11)

Non gas permeable, non-gas adsorption of density 1.40 g / cm ³ or more, and an inner layer made of a polyester film of 98% purity or more high density high purity, have a light shielding function, the inner layer of the same material and of the heterologous It is composed of a plurality of polyester films including an outer layer made of a low-density, low-purity polyester film, and the end portion of the sheet produced by superimposing the inner layer and the outer layer of the same material is heated by heat sealing. A gas sampling bag, which is sealed to form a sealed structure. The outer layer, which has a vapor-deposited layer of aluminum on at least one side of a polyester film as a base material, is configured as the vapor deposition layer is outermost, by heat-sealing, thermal contraction of the substrate and the deposited layer The gas sampling bag according to claim 1 , wherein a curl shape on the base material side of the vapor deposition layer is formed from the difference between the vapor deposition layers to ensure the sealing property between the vapor deposition layers . The gas sampling bag according to claim 1, wherein the outer layer is made of a polyester film containing a reagent having a light shielding function. The gas sampling bag according to any one of claims 1 to 3 , further comprising a coating layer made of an epoxy resin on at least a part of the outer layer. Non gas permeable, non-gas adsorption of density 1.40 g / cm ³ or more, and an inner layer made of a polyester film of 98% purity or more high density high purity, have a light shielding function, the inner layer of the same material and of the heterologous A method for producing a bag comprising a plurality of polyester films including an outer layer comprising a low-density low-purity polyester film, comprising the following steps:
(1) A step of producing a sheet by superimposing the inner layer and the outer layer (2) A step of folding the sheets or overlapping a plurality of sheets to match edges (3) An end of the sheet on which layers of the same material are superimposed (4) a cutter that can run parallel to the clamp, or an end of the sheet that can run parallel to the cutter. A step of cutting the portion (5) a step of heat-sealing the end portion of the sheet by heat-sealing treatment to produce a sealed bag body (6) a notch portion on the end portion or the sheet surface of the sheet And providing a gas intake / exhaust port having a light-shielding property (7) a step of performing a sealing process of the notch,
A process for producing a bag body for gas sampling, characterized in that when a heat seal bonding process at a plurality of locations is required, steps (3) to (5) are repeated to produce a sealed bag body. In the steps (1) and (5), the outer layer has an aluminum vapor deposition layer on at least one surface of a polyester film serving as a base material, and the vapor deposition layer is arranged on the outermost side, and is heat-sealed. 6. The gas sampling for gas sampling according to claim 5, wherein a curl shape on the base material side of the vapor deposition layer is formed from a difference in thermal shrinkage between the base material and the vapor deposition layer, and a sealing property between the vapor deposition layers is secured. A method for manufacturing a bag. In the step (1), the high-density high-purity polyethylene terephthalate film constituting the inner layer and the low-density low-purity polyethylene terephthalate film constituting the outer layer are the same in the winding direction and the axial direction in which the stretch ratio of each film is high. In addition to continuously supplying from each of the rolls wound so as to produce the sheet, the heat seal adhesion treatment for the end of each film is performed in the same direction as the axial direction with a high stretch ratio The manufacturing method of the bag body for gas sampling of Claim 5 or 6 . When processing folding the sheet in the step (2), claim and performs against bulge occurs at both ends of the該折return part or folded edges, the point seal process by pre ultrasound 5-7 The manufacturing method of the bag body for gas sampling in any one of . In the step (5), a gap is provided between the end face of the sheet and the heating portion so that the temperature of the end heated by the heating portion is within the melting temperature region of the polyester film, and the gap The gas sampling bag body according to any one of claims 5 to 8, wherein the end part is gradually melted and integrated by running the clamp or / and the heating part while maintaining the distance. Method. In the steps (4) and (5), the traveling speed of the clamp or / and the heating unit is set to a speed substantially equal to or not exceeding the thermal shrinkage speed of the sheet or the shrinkage speed due to heating and melting. A method for producing a gas sampling bag according to claim 9. In the subsequent step of any one of the steps (4), (5) or (7), at least a part of the bag body is subjected to a coating treatment with an epoxy resin at a temperature condition of 130 to 140 ° C. method for producing a gas sampling bag body according to any of claims 5 -10.

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