TW201600411A - Accommodating bag, container for storing accommodating bag, and accommodating bag forming composite film - Google Patents

Abstract

An object of the present invention is to provide an accommodating bag which can maintain practical quality of a storing object in the accommodating bag, a container for storing the accommodating bag, and an accommodating bag-forming composite film. The object is attained by providing an accommodating bag for placing a storing object, wherein the accommodating bag is formed by a composite film in a pouch form, the composite film comprises an inner film which contacts to the storing object in the bag and an outer film which does not contact to the storing object, and the inner film is a low density polyolefin film and is composed of a film such that an amount of eluted C10 to C28 Alkane is 200ppm or less in Toluene conversion when 13mL of dimethyl carbonate is placed in contact with the inner film and the contact area of the inner film to dimethyl carbonate is 45000mm2.

Description

a storage bag, a container in which the storage bag is housed, and a composite film for forming the storage bag

The present invention relates to a storage bag, a container in which the bag is housed, and a composite film for forming the storage bag. More specifically, the present invention relates to a storage bag capable of retaining the quality of a stored food such as a food, a beverage, a medicine, a solvent, or an electronic device, and a container containing the storage bag, and a composite film for forming the storage bag.

For example, various liquids such as foods, medicines, beverage water, and solvents are placed in a storage bag and transported to a factory or a storefront. This storage bag is manufactured using various resin compositions. Among them, there is a resin composition for a storage bag which has a low molecular weight resin component which is eluted from the storage bag with respect to the liquid contained in the storage bag.

For example, Patent Document 1 discloses a resin such as a low-density polyethylene or a linear low-density polyethylene or a composition thereof, which is used for the production of a bag for pickles, a bag for use, a tube for ice, and the like, and for loading the bag. Or the liquid in the tube, the low molecular weight resin component eluted from the bag or the tube is less.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 9-87443

However, even if the resin described in Patent Document 1 is used, the low molecular weight resin component is eluted, and there is a problem that the liquid quality cannot be maintained.

The present invention has been made in view of the above problems, and an object thereof is to provide a storage bag capable of substantially maintaining the quality of a storage item loaded in a storage bag. Further, a container in which the storage bag is housed and a composite film for forming the storage bag are provided.

The present inventors have found that when 13 mL of dimethyl carbonate is brought into contact with the above-mentioned inner film having a contact area of 45,000 mm ² of dimethyl carbonate, the elution amount of C ₁₀ -C ₂₈ alkane is 200 ppm or less in terms of toluene. The low density polyethylene film or the linear low density polyethylene film can solve the above problems, and the present invention has been completed.

The storage bag of the present invention for solving the above problems is a storage bag for accommodating the object to be stored, and a composite film having an inner film on the side in contact with the object to be stored and a film on the outer side not contacting the object to be stored. Formed in a bag shape; the inner film is a low-density polyolefin film, and when 13 mL of dimethyl carbonate is brought into contact with the inner film of the dimethyl carbonate having a contact area of 45,000 mm ² , the elution amount of the C ₁₀ -C ₂₈ alkane depends on The conversion of toluene is below 200 ppm.

The storage bag of the present invention may be a double bag type bag in which the inner film and the outer film are joined to each other by a peripheral edge.

The storage bag of the present invention may be a storage medium wafer or an electrolyte solution for a lithium ion battery.

The container of the present invention for solving the above-described problems includes a container having an outer container and a storage bag, the outer container having an opening; the storage bag being housed in the outer container and having a discharge port corresponding to the opening The storage bag is stored in the outer casing and then filled with a liquid, and is formed into a bag by a composite film having an inner film on the side in contact with the liquid and a film on the outer side contacting the outer container. The inner film is a low-density polyolefin film, and when 13 mL of dimethyl carbonate is brought into contact with the inner film having a contact area of 45,000 mm ² of the dimethyl carbonate, the amount of C ₁₀ -C ₂₈ alkane eluted is in terms of toluene. 200ppm or less.

The container of the present invention may also be an electrolyte solution for a lithium ion battery of the above liquid system.

The composite film of the present invention for accommodating the above-mentioned problem is a composite film for storing a storage bag, and has an inner film on the side in contact with the object to be stored and a side that is not in contact with the object to be stored. The outer film; the inner film is a low-density polyolefin film, and when 13 mL of dimethyl carbonate is brought into contact with the inner film having a contact area of 45000 mm ² of the dimethyl carbonate, the elution amount of the C ₁₀ -C ₂₈ alkane is converted into toluene. Below 200ppm.

According to the present invention, it is possible to provide a storage bag capable of substantially maintaining the quality of the contents stored in the storage bag, a container in which the storage bag is housed, and a composite film for forming the storage bag.

1‧‧‧ storage bag

2‧‧‧Composite film

3‧‧‧ bag body

3a‧‧‧Upper edge

3b‧‧‧ lower edge

3c‧‧‧lateral edge

4‧‧‧Note exports

4a‧‧‧Note Export Installation Department

4b‧‧‧Note Export and Cooperation Department

5‧‧‧Outer containers

6‧‧‧ injection nozzle

7‧‧‧ gas injection nozzle

7a‧‧‧ gas

8‧‧‧ 盖部

9‧‧‧Flange

10‧‧‧Heat seal

10a‧‧‧Top edge heat seal

10b‧‧‧Bottom edge heat seal

10c‧‧‧Side edge heat seal

11‧‧‧Liquid

20‧‧‧Outer film (outer bag)

21‧‧‧ inside film (inside bag)

22‧‧‧ Openings

23‧‧‧ Space Department

24‧‧‧Nozzle front end

25‧‧‧ openings

30‧‧‧ Container

Fig. 1 is a front elevational view showing an example of a storage bag of the present invention.

2(A) and 2(B) are cross-sectional views showing an example of a composite film of the present invention.

Figure 3 is a cross-sectional view showing an example of the container of the present invention.

Fig. 4 is a view showing a state in which a gas is injected into a container shown in Fig. 3, a storage bag is compressed, and a liquid in the storage bag is taken out.

Fig. 5 is a graph showing the results of measurement by a gas chromatography mass spectrometer when a C ₁₀ -C ₁₈ alkane released from various films was heated by a pyrolyzer at 80 ° C for 5 minutes.

Hereinafter, the storage bag of the present invention, the container in which the storage bag is housed, and the composite film for forming the storage bag will be described with reference to the drawings. Further, the present invention is not limited to the following embodiments.

[storage bag]

The storage bag of the present embodiment is a storage bag (storage bag) for storing articles such as foods, beverages, medicines, solvents, and electronic device parts. For example, when the liquid is stored in the storage bag, as shown in FIGS. 1 and 2, the storage bag 1 is stored in the outer container 5 (see FIG. 3), and then used until the liquid 11 is filled. The storage bag 1 is formed of a composite film 2 having an inner film 21 on the side in contact with the liquid 11 and an outer film 20 on the side not contacting the liquid 11 (that is, the side in contact with the outer container 5), and is formed in a bag shape. The inner film 21 constituting the composite film 2 is composed of a low-density polyolefin film. When the inner film 21 is made by contacting 13 mL of dimethyl carbonate to the inner film having a contact area of 45,000 mm ² of the dimethyl carbonate, the amount of elution of the C ₁₀ to C ₂₈ alkane is 200 ppm or less in terms of toluene.

Since the inner film 21 on the side in contact with the object to be stored such as the liquid 11 is formed of the above-described film, the storage bag 1 can further reduce the dissolution (dissolution) of the C ₁₀ to C ₂₈ alkane from the inner film 21 to the storage bag 1 . The amount of the liquid 11 or the amount that flows out (releases) into the gas contained in the storage bag 1. As a result, the storage bag 1 is suppressed due to elution of C ₁₀ ~ C ₂₈ alkane or release caused by decreased mass storage article case, the substance can be maintained while accommodating goods quality. Moreover, C ₁₀ ~ C ₂₈ alkane eluted from the inside of the film 21 to the liquid storing bags accommodated the maximum amount of 1 to 11, with the release of C ₁₀ ~ C ₂₈ alkanes from the inside to the film pouch 21 of the housing 1 of the gas most A lot of the same.

When the object to be stored is a liquid such as food, beverage water, liquid medicine, or solvent, the storage bag 1 can suppress the deterioration of the quality of the liquid 11 due to the elution of the C ₁₀ to C ₂₈ alkane, and can substantially maintain the quality of the liquid 11 . In particular, when the storage material is a liquid that is required to maintain quality, such as an electrolyte solution for a lithium ion battery, the storage bag 1 can suppress deterioration of characteristics of an electrolyte solution for a lithium ion battery or the like due to elution of a C ₁₀ to C ₂₈ alkane. In addition, the quality of the electrolyte for lithium ion batteries and the like can be substantially maintained.

In addition, when the object to be stored is a solid such as a food, a medicine, or an electronic device, the storage bag 1 can suppress the deterioration of the solid matter quality due to the elution of the C ₁₀ to C ₂₈ alkane, and can substantially maintain the solid matter. Quality. In particular, when the storage object is a precision component such as a wafer, the storage bag 1 can be used as a transfer bag when the precision component is shipped to another factory. Because the pouch is C 1 release alkane ₁₀ ~ C ₂₈ is very small, and thus solved by C ₁₀ ~ C ₂₈ alkane release caused by surface adsorption of precision parts C ₁₀ ~ C ₂₈ alkane, causing problems can not form a thin film. As a result, the storage bag 1 can prevent the wafer yield from being lowered, and can substantially maintain the quality of the precision parts.

In addition, the above-mentioned "substantially retained" means a range that does not affect the quality of the stored product, and more specifically, does not cause the taste, odor, function, action, characteristics, or workability of the stored article. The scope of influence.

Next, the storage bag of the present invention will be described in detail. Hereinafter, the storage bag 1 in which the liquid is stored will be described as an example.

(composite film)

The composite film 2 is composed of an inner film 21 and an outer film 20 as shown in Fig. 2(A). The inner film 21 is disposed on the side that is in contact with the liquid 11, and the outer film 20 is disposed on the side that does not contact the liquid 11 (that is, contacts one side of the outer container 5). In the storage bag 1, the composite film 2 is cut into an arbitrary shape, and the composite film 2 is placed in a state in which the inner film 21 faces each other, and then the peripheral edge 3 of the three sides or four sides is fixed by heat sealing (3a, 3b, 3c). The heat seal portion 10 is formed by lamination, and can be manufactured by being formed into a bag shape.

The composite film 2 may also have a multiple film including the inner film 21 and the outer film 20 as described above, or may have a multilayer thin film including the inner film 21 and the outer film 20 as shown in FIG. 2(B). membrane. The multilayer film can be produced by a generally known production method, and can be produced by a co-extrusion method, a lamination method, a heat sealing method, or the like.

The composite film 2 may contain an intermediate film (not shown) of 1 or 2 or more between the inner film 21 and the outer film 20. The intermediate film is applicable to the film used in the art.

(inside film)

The inner film 21 is disposed on the side contacting one of the liquids 11. The inner film 21 is composed of a low density polyolefin film.

The low-density polyolefin film may be, for example, a film of a low-density polyolefin resin such as a low-density polyethylene resin or a low-density polypropylene resin or a copolymer resin of two kinds of low-density polyolefin resins. Further, when the low-density polyolefin film is a linear low-density polyolefin film, the linear low-density polyolefin film may be, for example, a linear low-density polyethylene resin or a linear low-density polypropylene resin. A film such as a linear low-density polyolefin resin or a copolymer resin of two kinds of linear low-density polyolefin resins. In particular, the low-density polyethylene resin and the linear low-density polyethylene resin have flexibility and can be reduced in cost. Further, in the examples described later, a representative example is a low-density polyethylene resin or a linear low-density polyethylene resin.

The low-density polyolefin film is obtained by contacting 13 mL of dimethyl carbonate with the above-mentioned inner film having a contact area of 45,000 mm ² of dimethyl carbonate, and the amount of C ₁₀ -C ₂₈ alkane which is a low molecular weight resin component is dissolved in toluene. The conversion is below 200ppm. The amount of elution of the C ₁₀ to C ₂₈ alkane is preferably 150 ppm or less in terms of toluene. According to this, the inner film 21 of the storage bag 1 is formed by using a low-density polyolefin resin having a C ₁₀ -C ₂₈ alkane elution amount of 200 ppm or less or a copolymer resin of two kinds of low-density polyolefin resins. Since the C ₁₀ -C ₂₈ alkane which is a low molecular weight resin component can be eluted from the inner film 21 to the amount of elution in the liquid 11 accommodated in the storage bag 1, the quality of the liquid 11 accommodated in the storage bag 1 can be substantially maintained.

The C ₁₀ -C ₂₈ alkane system can be, for example, C ₁₀ H ₂₂ , C ₁₁ H ₂₄ , C ₁₂ H ₂₆ , C ₁₃ H ₂₈ , C ₁₄ H ₃₀ , C ₁₅ H ₃₂ , C ₁₆ H ₃₄ , C ₁₇ H ₃₆ , C ₁₈ H ₃₈ , C ₁₉ H ₄₀ , C ₂₀ H ₄₂ , C ₂₁ H ₄₄ , C ₂₂ H ₄₆ , C ₂₃ H ₄₈ , C ₂₄ H ₅₀ , C ₂₅ H ₅₂ , C ₂₆ H ₅₄ , C ₂₇ H ₅₆ , C ₂₈ H ₅₈ and the like. These lines may be one type or two or more types. Further, the reason why the alkane is limited to C ₁₀ to C ₂₈ is that when various low-density polyolefin films are brought into contact with dimethyl carbonate, it is impossible to confirm the elution of an alkane having a carbon number of less than 10 and an alkane having a carbon number of more than 28. .

The elution of the C ₁₀ -C ₂₈ alkane from the inner film 21, for example, by immersing the inner film 21 in dimethyl carbonate for a predetermined time and a predetermined temperature, can be confirmed by the presence of C ₁₀ - C _{28 in the} dimethyl carbonate. Alkanes were evaluated. The method for confirming the presence of C ₁₀ to C ₂₈ alkane can be carried out by, for example, gas chromatography, gas chromatography mass spectrometry, liquid chromatography or the like. Moreover, the elution amount of C ₁₀ ~ C ₂₈ alkane obtained from the system according to the various chromatographic chromatograph, and can be calculated by toluene conversion.

Further, the release of the C ₁₀ -C ₂₈ alkane from the inner film 21 is filled with nitrogen gas, for example, in a bag made of the inner film 21, and is allowed to stand at a predetermined temperature for a predetermined time, by confirming whether or not the gas in the bag is present. ₁₀ ~ C ₂₈ alkane can be evaluated. C ₁₀ ~ C ₂₈ paraffinic presence confirmation method by analysis such as gas chromatography, gas chromatography, mass spectrometry, or the like may be implemented. Further, a part of the above-mentioned bag was cut out, and the presence of a C ₁₀ -C ₂₈ alkane was confirmed by using a double cracker (Double-Shot Pyrolyzer) and a gas chromatography mass spectrometer. Further, the amount of C ₁₀ -C ₂₈ alkane released can be calculated from the chromatogram obtained from various chromatographs by conversion in toluene.

The thickness of the inner film 21 is not particularly limited, and is usually in the range of 10 μm or more and 120 μm or less, more preferably in the range of 30 μm or more and 100 μm or less. Such an inner film 21 can be formed by a general film forming means such as an inflation method.

(outer film)

The outer film 20 is disposed on the side that does not come into contact with one side of the liquid 11 and that comes into contact with the outer casing 5. That is, it is disposed on the outermost side of the composite film. The outer film 20 can use a film used in the art.

Further, when the liquid 11 is a solution which is hydrolyzed by moisture such as an electrolyte solution for a lithium ion battery, it is preferred to form a resin having a small amount of the outer side film 20. By using the outer side film 20 having a small amount of water, it is possible to suppress the deterioration of the battery characteristics caused by hydrolysis of the electrolyte solution for a lithium ion battery or the like. Further, the resin which can form the outer side film 20 having a small amount of water can be, for example, a polyethylene terephthalate resin or a polybutylene terephthalate resin.

The thickness of the outer film 20 is not particularly limited, but is usually in the range of 10 μm or more and 120 μm or less, preferably 30 μm or more and 80 μm or less. Such The outer film 20 can be formed by a general film forming means such as an inflation method.

(formation of storage bag)

The storage bag 1 is formed by laminating the inner film 21 and the outer film 20 to form a composite film 2, and can be formed of the laminated composite film 2. Specifically, this formation is such that the inner film 21 is placed on the liquid 11 side, and the composite film 2 is opposed to the composite film 2, and the opposite inner films 21 and 21 are bonded to each other. The bonding is usually preferably carried out by heat sealing, but is not limited thereto.

The shape of the storage bag 1 can be, for example, a bag shape, a box shape, a tubular shape, or the like. The bag-shaped (especially double-layered bag) storage bag 1 can be formed, for example, by laminating two composite films 2 and 2 and joining the peripheral edges thereof. More specifically, the composite film 2 in which only the peripheral edge is joined or entirely joined between the inner film 21 and the outer film 20 is formed so as to overlap with the inner film 21 of the composite film 2, and further formed by peripheral bonding. Further, the two laminated composite films 2 may be the same or different. In addition, the inner film 21 and the outer film 20 are not joined, and only the superposed composite film 2 is superposed on each other so as to be in contact with the inner film 21 of the composite film 2, and then formed by peripheral bonding.

The bonding of the peripheral edges described above can be carried out, for example, by heat sealing. As shown in FIG. 1, the bonding system can heat-treat the four sides of the composite film 2. When the folded composite film 2 is overlapped, the three sides can be heat-sealed. Further, each of the inner edges of the heat-sealed portion may have an inner edge formed in an arc shape. This makes it possible to have a structure in which it is difficult to leave a fluid storage material in each part.

As described above, when the storage bag 1 is a double-pocket bag formed by joining the peripheral edges between the inner film 21 and the outer film 20, since the outer film 20 can be used with a durable film which is generally used, durability can be provided. Good storage bag 1. Further, since the double bag type bag can suppress the deterioration of the quality of the liquid 11 caused by the elution of the C ₁₀ ~ C ₂₈ alkane from the inner film 21, the C ₁₀ ~ C ₂₈ alkane released from the outer film 20 can be prevented from being affected by the inner film 21 When it is moved to the liquid 11, the quality of the liquid 11 can be substantially maintained. Further, the peripheral edge of the inner film 21 and the outer film 20 can be easily joined by providing, for example, a heat seal layer on one side of the inner film 21 and the outer film 20.

The method for producing the storage bag 1 is not limited to the above-described heat sealing method, and a method such as a coextrusion method or a lamination method may be used. By manufacturing the storage bag 1 in this manner, the inner bag 21 of the composite film 2 can be used to form the inner bag 21 filled with the liquid 11 (the inner bag is formed of the inner film 21, so the same component symbol "21" is given), and the composite is utilized. The outer film 20 of the film 2 forms the outer bag 20 in which the inner bag 21 is housed (since the outer bag is constituted by the outer film 20, the same component symbol "20" is given).

(liquid)

The liquid 11 is filled in the storage bag 1, and is not particularly limited as long as it is a solution which is resistant to the inner film 21. For example, an electrolyte solution for a lithium ion battery or polylactic acid is used. A solution in which the liquid system is hydrolyzed by moisture. Others may be, for example, a photoresist removal liquid, an etching liquid, or another chemical liquid used in the semiconductor manufacturing step. Others may, for example, guide the photoresist removal liquid used in the frame manufacturing step, the etching liquid, the photoresist removal liquid or the etching liquid used in the suspension substrate manufacturing step, the printing ink used in the printing step, High purity liquid, liquid Pharmaceuticals, beverages, solvents, etc.

Further, the electrolyte solution for a lithium ion battery can dissolve, for example, an organic electrolyte such as LiPF ₆ , LiC1 O ₄ , LiBF ₄ , LiN(SO ₂ CF ₃ ) ₂ , LiN(SO ₂ C ₂ F ₅ ) ₂ or the like belonging to a lithium salt. .

[container]

As shown in FIG. 3 and FIG. 4, the container 30 of the present invention includes an exterior container 5 in which the opening 22 is provided, and an accommodation container 4 accommodated in the exterior container 5 and provided with a discharge port 4 corresponding to the opening 22. Bag 1. In the container 30, the storage bag 1 is housed in the outer casing 5, and then the liquid 11 is filled. The storage bag 1 is formed in a bag shape by a composite film 2 having an inner film 21 on the side in contact with the liquid 11 and an outer film 20 on the side in contact with the outer container 5, which is formed in a bag shape. In the 21-type low-density polyolefin film, when 13 mL of dimethyl carbonate is brought into contact with the inner film having a contact area of 45,000 mm ² of the dimethyl carbonate, the amount of elution of the C ₁₀ -C ₂₈ alkane is 200 ppm or less in terms of toluene.

The storage bag 1 constituting the container 30 is the same as described above, and the effects are also the same. In addition, as shown in FIG. 4, the container 30 is fed between the outer container 5 and the storage bag 1 via the gas injection nozzle 7 (space portion 23). Since the gas 7a is compressed, the liquid 11 in the storage bag 1 can be discharged from the injection port 4 through the nozzle tip end 24 and the dispensing nozzle 6 without the gas 7a coming into direct contact with the liquid 11.

The outline of the related container 30 will be described with reference to Fig. 3 .

The container 30 is provided with an exterior container 5, a storage bag 1, and a lid portion 8. The outer casing 5 may be made of metal (canister) or made of resin. The metal exterior container 5 is preferably made of, for example, a stainless steel material. The storage bag 1 is a bag-shaped container housed in the outer casing 5. The lid portion 8 is for sealing the outer container 5. The storage bag 1 includes an inner bag 21, an outer bag 20, a lid portion 8, and a dispensing nozzle 6.

The inner bag 21 is filled with the liquid 11, and is formed of the inner film 21 described above. The outer bag 20 accommodates the inner bag 21 and is formed of the outer film 20 described above. The bag body 3 of the storage bag 1 integrally seals the inner bag 21 and the outer bag 20, and the upper edge heat seal portion 10a and the bottom edge heat seal portion 10b are formed on the upper edge 3a, the lower edge 3b, and the side edge 3c, respectively. It can be manufactured by the side edge heat sealing part 10c.

The lid portion 8 is for connecting both the storage bag 1 and the outer container 5. The injection port mounting portion 4a of the injection port 4 to which the lid portion 8 is connected is inserted into the opening portion 25 of the inner bag 21 and the outer bag 20, and the inner bag 21 and the outer bag 20 are integrally sealed to hold the inner bag 21 And fixed. The injection nozzle 6 is a tube for discharging the liquid 11 in the inner bag 21 to the outside. The nozzle 6 for injection is inserted into the hole of the lid portion 8.

The lid portion 8 is opened and closed by the injection port of the storage bag 1. The opening 22 is configured to detachably connect the injection port 4 of the storage bag 1.

The nozzle 6 for injection is used for discharging liquid. The injection nozzle 6 is provided in the hole portion of the injection port 4. The gas injection nozzle 7 is used for the outer container 5 and the storage bag 1 The space portion 23 injects a passage of the gas 7a. The gas 7a to be injected into the gas injection nozzle 7 may be, for example, nitrogen, air, oxygen, carbon dioxide or the like. The gas injection nozzle 7 is provided on the flange 9 at the upper portion of the outer casing 5.

Further, when the injection port engagement portion 4b of the injection port 4 is connected and fixed to the lid portion 8, the hole portion of the injection port 4 and the hole portion of the lid portion 8 are closed, and the injection port 4 and the injection nozzle are further closed. 6 phase connection. In this case, the liquid in the storage bag 1 can be ejected from the injection nozzle 6 via the injection port 4.

In the present embodiment, the storage opening engagement portion 4b is connected to the lid portion 8 to hold the storage bag 1 housed in the outer casing 5, but the injection port engagement portion 4b and the lid portion 8 may be integrated. The storage bag 1 is housed in the outer casing 5 and held by the opening 22 provided in the outer casing 5. In this case, the lid portion 8 is fixed in contact with the outer container 5, and the inside of the storage bag 1 is sealed. Further, the fixing portion of the lid portion 8 to the outer container 5 can be implemented by, for example, a bolt or the like.

In addition, as shown in FIG. 4, the gas 7a is injected into the space portion 23 between the outer casing 5 and the storage bag 1 via the gas injection nozzle 7, as shown in FIG. In other words, by injecting the gas 7a into the space between the outer casing 5 and the liquid bag 1, the space is expanded, whereby the storage bag 1 is pressed and the liquid is withdrawn.

On the other hand, the injection of the liquid can directly fill the liquid into the inner bag 21 of the storage bag 1 via the injection port 4 and the discharge nozzle 6, but the inside of the inner bag 21 can also be used when the storage bag 1 is folded. Injecting an inert gas such as nitrogen to expand the inner bag 21 and the outer bag 20 After that, the liquid is injected again.

When a liquid such as an electrolyte solution for a lithium ion battery is filled into the inner bag 21, since a liquid such as an electrolyte solution for a lithium ion battery is more likely to be wet, it is necessary to appropriately manage the dew point in the storage bag 1. That is, it is preferable to lower the moisture content in the air by lowering the dew point temperature to about -50 ° C to -70 ° C, and then filling the inner bag 21 with a liquid such as an electrolyte solution for a lithium ion battery.

[Examples]

The present invention will be described in more detail by way of the following experimental examples, but the present invention is not limited to the materials and the like used in the following examples. In addition, each experimental system described later changed the type of the inner film constituting the composite film, and the pseudo-evaluation of the bag was performed, and the evaluation result was not performed in the form of a bag.

[Experiment 1] (production of various films)

Each of the resin films shown in Table 1 was used, and various sample films having a thickness of 80 μm were produced by an inflation film forming apparatus (manufactured by WINDMOELLER & HOELSCHER CORPORATION). Further, 5 g of various resin particles were immersed in 13 mL of a solvent (dimethyl carbonate: DMC), and allowed to stand at 60 ° C for one week. Then, using a gas chromatography mass spectrometer (manufactured by Shimadzu Corporation, product name: GCMS-QP2010), it was confirmed whether or not there was a C ₁₀ -C ₂₈ alkane eluted from the resin particles in the solvent. Further, the C ₁₀ to C ₂₈ alkane concentration (ppm) in the solvent was calculated in terms of toluene based on the chromatogram obtained by a gas chromatography mass spectrometer. The results are shown in Table 1.

-: not determined

[Experiment 2] (Low-molecular weight resin component for dissolution test of various films)

9 sheets of a film having a size of 25 mm × 100 mm were cut out from the film of the sample 1 to 9 prepared, and 13 mL of dimethyl carbonate (DMC) immersed in a solvent for an electrolyte solution for a lithium ion battery was allowed to stand at 60 ° C for one week. Then, it was confirmed using a gas chromatography mass spectrometer whether or not the C ₁₀ -C ₂₈ alkane was eluted from the film to DMC. Further, based on the chromatogram obtained by a gas chromatography mass spectrometer, the amount of C ₁₀ to C ₂₈ alkane (ppm) eluted to 13 mL of DMC from a film having a contact area of 45,000 mm ² in contact with DMC was calculated in terms of toluene. The results are shown in Table 2. Further, the detection limit concentration of various alkanes measured by a gas chromatography mass spectrometer was 5 ppm in terms of toluene.

From the chromatographic results, it was confirmed that the samples of the sample 8 and the sample 9 were clearly found to have peaks of any kind of alkane, but the films of the samples 1 to 7 were confirmed to have only a small amount of alkane elution (not shown). Further, it was confirmed that the low molecular weight resin component eluted from the film of the sample 8 and the sample 9 to the DMC was a C ₁₀ to C ₂₈ alkane. Further, as shown in Table 2, a film made of a low-density polyethylene resin or a linear low-density polyethylene resin particle having a C ₁₀ -C ₂₈ alkane elution amount of more than 1000 ppm in terms of toluene under the predetermined conditions ( In the sample 8 and the sample 9), the amount of C ₁₀ to C ₂₈ alkane eluted to 13 mL of DMC from the film having a contact area of 45,000 mm ² in contact with DMC was more than 200 ppm in terms of toluene. On the other hand, a film made of a low-density polyethylene resin or a linear low-density polyethylene resin pellet having a C ₁₀ -C ₂₈ alkane elution amount of 1000 ppm or less in terms of toluene is prepared under the predetermined conditions (sample 1 to sample 7). The amount of the C ₁₀ -C ₂₈ alkane eluted to 13 mL of DMC from the film having a contact area of 45,000 mm ² in contact with DMC was 200 ppm or less in terms of toluene, and it was confirmed that the amount of elution was only slightly.

[Experiment 3] (Confirmation test for releasing low molecular weight resin components from storage bags of various films)

Generally, a wafer is formed by forming a photoresist film on the surface of the wafer, and then loading it into a storage bag and then shipping it to a film forming factory. In such a factory, the particles in the working environment are managed to a certain amount or less, and the film formation of the photoresist film is performed on the surface of the wafer by a spin coating device. However, even in such an environment, it is impossible to form a photoresist film on the surface of the wafer, which may cause a problem that the wafer yield is lowered. Therefore, the following experiment was carried out.

A small piece (8 mm × 8 mm) cut out from a storage bag made of the film of the samples 3 and 5, and a small piece (8 mm × 8 mm) in which a storage bag in which a hindered wafer was formed from a photoresist film on the surface was taken (8 mm × 8 mm; 10 and the film of the sample 11 were heated at 80 ° C for 5 minutes using a thermal cracker (Frontier Laboratories Co., Ltd., product name: PY-2020D), and then confirmed by gas chromatography mass spectrometry from a small piece. Release C ₁₀ ~ C ₁₈ alkane. The result is shown in Figure 5.

As shown in FIG. 5, a film (sample 10 and film 11 of sample 11) in which a surface resist film was formed to form a storage bag of a hindered wafer was stored, and it was confirmed that a large amount of polyolefin (C ₁₀ -C ₁₈ alkane) was released. Polyolefins can hinder the formation of photoresist films. On the other hand, the polyolefin (C ₁₀ -C ₁₈ alkane) was slightly released from the films of the samples 3 and 5, and it was confirmed that half of the film of the sample 11 was not released.

In fact, in the wafer accommodated in the storage bag manufactured by the film of the samples 3 and 5, it was confirmed that the photoresist film can be formed on the surface without any problem, and the quality of the wafer can be maintained.

From these matters, a film made of a low-density polyethylene resin or a linear low-density polyethylene resin pellet having a C ₁₀ -C ₂₈ alkane elution amount of 1000 ppm or less in terms of toluene under a predetermined condition is a C ₁₀ The release of ~C ₁₈ alkane is only marginal and does not affect wafer quality.

1‧‧‧ storage bag

2‧‧‧Composite film

3‧‧‧ bag body

3a‧‧‧Upper edge

3b‧‧‧ lower edge

3c‧‧‧lateral edge

4‧‧‧Note exports

4a‧‧‧Note Export Installation Department

4b‧‧‧Note Export and Cooperation Department

10‧‧‧Heat seal

10a‧‧‧Top edge heat seal

10b‧‧‧Bottom edge heat seal

10c‧‧‧Side edge heat seal

20‧‧‧Outer film (outer bag)

21‧‧‧ inside film (inside bag)

Claims (6)

A storage bag is a storage bag for accommodating a storage object, and is characterized in that a composite film having an inner film that is in contact with the object to be stored and a film that is not in contact with the outer side of the object to be stored is formed as a bag-like shape; the inner film is a low-density polyolefin film, and when 13 mL of dimethyl carbonate is brought into contact with the inner film having a contact area of 45,000 mm ² of the dimethyl carbonate, the elution amount of the C ₁₀ -C ₂₈ alkane is converted into toluene. Below 200ppm. The storage bag according to claim 1, wherein the inner film and the outer film are joined to each other by a double bag type bag. The storage bag according to claim 1 or 2, wherein the object to be stored is a wafer or an electrolyte solution for a lithium ion battery. A container having a container having an outer container and a storage bag, wherein the outer container is provided with an opening; the storage bag is housed in the outer container and has a discharge port corresponding to the opening; The storage bag is stored in the outer casing and then filled with a liquid, and the composite film having the inner film on the side in contact with the liquid and the outer film on the side in contact with the outer container is formed into a bag shape; When the inner film is a low-density polyolefin film, when 13 mL of dimethyl carbonate is brought into contact with the inner film having a contact area of 45,000 mm ² of the dimethyl carbonate, the amount of elution of the C ₁₀ -C ₂₈ alkane is 200 ppm or less in terms of toluene. The container of claim 4, wherein the liquid electrolyte solution for a lithium ion battery. A composite film for storing a storage bag for a storage bag, comprising: an inner film on a side in contact with the object to be stored; and an outer film on a side not contacting the object to be stored; When the inner film is a low-density polyolefin film, when 13 mL of dimethyl carbonate is brought into contact with the inner film having a contact area of 45,000 mm ² of the dimethyl carbonate, the amount of elution of the C ₁₀ -C ₂₈ alkane is 200 ppm or less in terms of toluene.