JP2021160172A - Gas adsorption laminate for liquid content packaging - Google Patents

Abstract

To provide a laminate which is excellent in manufacture suitability, exhibits a high gas adsorption effect and odor taste change resistance for a long period of time, is excellent in pinhole resistance, falling body resistance and water leakage resistance in storage and transportation vibration, and is excellent in easy needle piercing properties in usage, and a packaging material and a package using the laminate.SOLUTION: A laminate for liquid content packaging has an easy piercing sealant layer 2 on one surface and a gas adsorption sealant layer 4 on the other surface, in which the easy piercing sealant layer 2 contains easy piercing polyethylene and a flexibility-imparting resin, the gas adsorption sealant layer 4 contains low elution polyethylene, the flexibility-imparting resin and a gas adsorbent, concentration of elusion TOC contained in the low elution polyethylene is 1.5 ppm or more and 250 ppm or less, a layer thickness ratio of the easy piercing sealant layer to the gas adsorption sealant layer is 0.3 to 0.8, and the gas adsorbent contains hydrophobic zeolite.SELECTED DRAWING: Figure 1

Description

The present invention relates to a liquid content packaging laminate having easy needle piercing property, pinhole resistance, and gas adsorption property, and a packaging material for liquid content packaging produced by using the liquid content packaging laminate. , Regarding liquid contents packaging.

As a packaging material, a packaging material containing an odor adsorbent has been proposed. In such a packaging material, an odor adsorbent such as synthetic zeolite or activated carbon is kneaded into the resin material. (Patent Document 1) However, such a packaging material has a problem that it adsorbs not only an odor but also moisture in the air and desorbs the once adsorbed odor, so that the odor is sufficient. No adsorption effect can be obtained. In addition, the ease of needle piercing property for packaging liquid contents is not considered.
A packaging material containing an odor adsorbent in which a chemical adsorbent is carried on an inorganic porous body is also known (Patent Document 2), but the main object to be adsorbed is only an odor component having a specific functional group. Therefore, it was not possible to sufficiently adsorb the odorous components of organic substances having no functional groups, which are generated when various resin materials are used. In addition, the easy needle puncture resistance and pinhole resistance required for liquid content packaging are not considered.

Japanese Patent No. 2538487 Japanese Unexamined Patent Publication No. 2014-23340

The present invention solves the above-mentioned problems, is excellent in manufacturing suitability such as film forming property, filling machine suitability, wrinkle resistance and printability, and exhibits high gas adsorption effect and odor resistance changeability for a long period of time. Excellent seal strength and slidability (low friction), excellent pinhole resistance, drop body resistance, and water leakage resistance during storage and transportation vibration, and excellent needle puncture resistance at the start of use. It is an object of the present invention to provide a laminated body, a packaging material using the laminated body, and a packaging body.

As a result of various studies, the present inventors have found that a laminate having a specific easily piercing sealant layer and a specific gas adsorption sealant layer achieves the above object.
The present invention is characterized by the following points.
1. 1. A laminate for packaging liquid contents, which has an easily piercing sealant layer on one surface and a gas adsorption sealant layer on the other surface.
The easy-to-pierce sealant layer contains easy-to-penetrate polyethylene and a flexibility-imparting resin.
The gas adsorption sealant layer contains low-eluting polyethylene, the flexibility-imparting resin, and a gas adsorbent.
The concentration of elution TOC contained in the low-eluting polyethylene is 1.5 ppm or more and 250 ppm or less.
The layer thickness ratio of the easy-to-pierce sealant layer / gas adsorption sealant layer is 0.3 to 0.8.
The gas adsorbent contains a hydrophobic zeolite,
The laminate for packaging the liquid contents.
2. The laminate for packaging liquid contents according to 1 above, wherein the gas adsorbent further contains an inorganic porous body carrying a chemical adsorbent.
3. 3. The easy-piercing sealant layer is a layer for imparting easy-needle piercing property to the laminated body, and is used so that the needle first comes into contact with the outside air when the needle is pierced, and has a thickness of 20 μm or more. , 40 μm or less,
The gas adsorption sealant layer is a layer for imparting gas adsorptivity to the laminate, which is used in contact with the liquid content, and contains gas components and / or the laminate. By sterilization treatment using one or more selected from the group consisting of ultraviolet irradiation, heating (hot pack), and boiling, the gas component consisting of the resin decomposition product generated from the laminate for packaging the liquid contents is adsorbed. The layer is 40 μm or more and 70 μm or less in thickness.
The laminate for packaging liquid contents according to 1 or 2 above.
4. The laminate for packaging liquid contents according to any one of 1 to 3 above, wherein the easily piercing polyethylene is C4-LLDPE.
5. The flexibility-imparting resin is an olefin-based thermoplastic elastomer and / or an olefin-based plastomer.
Of the softening resins, density, 0.85 g / cm ³ or more and 0.905 g / cm ³ or less, the Vicat softening point, 35 ° C. or more and 120 ° C. or less,
The laminate for packaging liquid contents according to any one of 1 to 4 above.
6. The laminate for packaging liquid contents according to any one of 1 to 5 above, wherein the content of the flexibility-imparting resin in the easily piercing sealant layer is 3% by mass or more and 25% by mass or less.
7. The laminate for packaging liquid contents according to any one of 1 to 6 above, wherein the low-eluting polyethylene ^{is LLDPE having a density of 0.90 g / cm 3} or more and 0.94 g / cm ^{3 or less.}
8. The liquid content packaging according to any one of 1 to 7 above, wherein the low-eluting polyethylene is one or more selected from the group consisting of C4-LLDPE, C6-LLDPE, and C8-LLDPE. Laminated body.
9. The laminate for packaging liquid contents according to any one of 1 to 8 above, wherein the content of the flexibility-imparting resin in the gas adsorption sealant layer is 2% by mass or more and 25% by mass or less.
10. The above 1 to 9 above, wherein the gas adsorbent is melt-kneaded in advance in a mass ratio of the thermoplastic resin and the gas adsorbent / thermoplastic resin at a ratio of 5/95 to 40/60. Laminate for packaging liquid contents.
11. The chemical adsorbent carried by the chemical adsorbent-supporting inorganic porous body has a functional group having reactivity with one or more selected from the group consisting of aldehydes, ketones, and carboxylic acids. The laminate for packaging liquid contents according to any one of 2 to 10 above.
12. The laminate for packaging liquid contents according to any one of 2 to 11 above, wherein the chemical adsorbent supported by the chemical adsorbent-supported inorganic porous body has an amino group or a hydroxyl group.
13. An intermediate layer is further included between the easily piercing sealant layer and the gas adsorption sealant layer.
The laminate for packaging liquid contents according to any one of 1 to 12 above, wherein the intermediate layer contains a polyamide resin.
14. The laminate for packaging liquid contents according to any one of 1 to 13 above, wherein the static friction coefficient of the easily piercing sealant layer is 0.04 or more and 0.3 or less.
15. A packaging material for liquid contents, which is produced by using the laminate for packaging liquid contents according to any one of 1 to 14 above.
16. A packaging material for a water server, which is produced from the laminate for packaging the liquid contents according to any one of 1 to 14 above.
17. A bag-in-box packaging material produced from the laminate for packaging the liquid contents according to any one of 1 to 14 above.
18. A liquid content package made from the liquid content packaging material according to 15 above.
19. A water server package made from the water server packaging material according to 16 above.
20. A bag-in-box package made from the bag-in-box packaging material according to 17 above.

According to the present invention, it is excellent in manufacturing suitability such as film forming property, filling machine suitability, wrinkle resistance generation and printability, exhibits high gas adsorption effect and odor resistance changeability for a long period of time, and exhibits seal strength and sliding. Due to its excellent properties (low friction), it is excellent in pinhole resistance, drop body resistance and water leakage resistance during storage and transportation vibration, and is excellent in needle puncture resistance at the start of use, and the laminate. It is possible to provide a packaging material and a packaging body using a laminated body.
In particular, a gas component contained in the resin itself contained in the laminate, or a gas composed of a resin decomposition product generated by decomposition of the resin constituting the packaging material during sterilization treatment using ultraviolet irradiation or heating. It has a high gas adsorption effect on the components and is excellent in easy needle piercing property at the start of use in a water server or the like.

It is a schematic cross-sectional view which shows an example about the layer structure of the laminated body for packaging liquid contents of this invention. It is a schematic cross-sectional view which shows an example of another aspect about the layer structure of the laminated body for packaging liquid contents of this invention. It is a schematic cross-sectional view which shows an example of still another aspect about the layer structure of the laminated body for packaging a liquid content of this invention. It is a figure which shows the adsorption mechanism with respect to the gas component of the chemical adsorbent-supported inorganic porous body. It is a schematic bird's-eye view which shows the weight for measuring the coefficient of static friction. It is a bird's-eye view which shows the state which fixed the laminated body of this invention to a weight. It is a figure which shows the measuring method of a static friction coefficient.

The laminate for packaging the liquid contents of the present invention, and the packaging material and the packaging produced by using the laminate for packaging the liquid contents will be described in detail below. The present invention will be described with reference to specific examples, but the present invention is not limited thereto.

<< Laminate for packaging liquid contents >>
The laminate for packaging liquid contents of the present invention has easy needle piercing property and gas adsorptive property, and is a laminate that suppresses the liquid contents from causing an offensive odor or a change in odor.
As shown in FIG. 1, the layer structure of the laminate for liquid content packaging of the present invention includes at least an easy-to-penetrate sealant layer and a gas-adsorbed sealant layer, and is composed of an easy-to-penetrate sealant layer and a gas-adsorbed sealant layer. Each is a surface layer of a laminate for packaging liquid contents, and when the package is formed, the easily piercing sealant layer is used so as to come into contact with the outside air, and the gas adsorption sealant layer is the liquid contents which are the contents of the package. It is used to contact with.
The inclusion of heat-sealable layers on both surfaces of the laminate for packaging liquid contents also makes it possible to fabricate various types of packaging with complex structures.

In addition, the laminate for packaging liquid contents of the present invention may further contain an intermediate layer having various performances, if necessary.
Furthermore, each layer may be laminated via an adhesive layer.

The thickness of the laminate for packaging the liquid contents of the present invention is preferably 100 μm or more and 130 μm or less, and more preferably 105 μm or more and 125 μm or less. If it is thinner than the above range, it is easily torn, and if it is thicker than the above range, the rigidity is likely to be too strong, and the suitability for packaging is likely to be inferior.
Further, the easily piercing sealant layer is preferably thinner than the gas adsorption sealant layer, and the layer thickness ratio of the easily piercing sealant layer / gas adsorption sealant layer is preferably 0.3 to 0.8. If it is smaller than the above range, the balance of the layer ratio is poor, and the production suitability at the time of producing the film may be inferior. If it is larger than the above range, the piercing strength may become too high.

The overall tensile elastic modulus of the laminate for packaging the liquid contents of the present invention is preferably 20 MPa or more and 300 MPa or less, and more preferably 22 MPa or more and 295 MPa or less. If it is lower than the above range, the rigidity is too small and wrinkles are likely to occur, and if it is higher than the above range, the rigidity is too strong and it tends to be difficult to handle as a packaging material.

The laminate for packaging liquid contents of the present invention has excellent gas adsorption property, easy needle piercing property, low TOC elution property, filling machine suitability, low wrinkle generation property, pinhole resistance, drop body resistance, and water leakage resistance. Since it has properties, these characteristics can be imparted to a gas-adsorptive packaging material for packaging liquid contents and a gas-adsorptive package for packaging liquid contents.
In addition, the laminate for packaging liquid contents can have high transparency depending on the application.

[Gas adsorption]
In the present invention, the gas adsorptivity refers to the ability to adsorb a gas component to be adsorbed.
In the present invention, the gas component to be adsorbed is mainly the gas component contained in the laminate itself and the resin decomposition generated by the decomposition of the resin in the laminate by the sterilization treatment using ultraviolet irradiation or heating. It is a gas component consisting of things. Here, the gas component originally contained in the laminated body is a gas component contained in the raw material constituting the laminated body and a gas component generated by the heat history when forming the laminated body.
Specific examples of the sterilization treatment using ultraviolet irradiation or heating include ultraviolet irradiation with a wavelength of 250 to 300 nm, hot pack, sterilization using boil, and the like.
An object of the present invention is to reduce the concentration of the gas component in the content or the content accommodating portion of the gas adsorption package produced by using the laminate for packaging the liquid content.
Here, the laminate for packaging the liquid contents of the present invention can adsorb the gas component before the gas component exits the laminate for packaging the liquid contents from the laminate for packaging the liquid contents to the content accommodating portion, and the liquid can also be adsorbed. It is also possible to adsorb the gas component emitted from the content packaging laminate to the content accommodating portion, and further, it is also possible to adsorb the gas component contained in the content.
The gas component to be adsorbed in the present invention is an organic substance having a relatively small molecular weight, and includes those that are easily vaporized, those that are soluble in water, those that are odorless, those that have a weak odor, and those that have a strong odor. The types are hydrocarbons, alcohols, aldehydes, ketones, carboxylic acids and the like.
Hydrocarbons are components that greatly contribute to an increase in TOC elution concentration, and alcohols, aldehydes, ketones, and carboxylic acids are components that enhance odor. By adsorbing these gas components as a whole, it is possible to achieve low TCO elution (reduction of the amount of elution components in the liquid) and improvement of odor resistance changeability (improvement of odor).
Specific compounds of hydrocarbons include propane, propene, butane, isobutane, 2-methylbutane, butene, isobutane, 2-methylpentane, 3-ethylpentane, 2,2-dimethylpentane, 3,3-dimethylpentane. , Hexane, cyclohexane, 2-methylhexane, 3-methylhexane, 2,5-dimethylhexane, heptane, 2-methylheptan, 3-methylheptan, 3-ethylheptan, 2,2,4,6,6-pentane Examples thereof include methylheptane, 3-ethyl-3-methylheptan, 3-methylheptane, octane, 2-methyloctane, 4-ethyloctane, nonane, 3-methylnonane, decane and dodecane.
Specific examples of alcohols include 2-methyl-2-propanol, 2-methylpropanol, ethanol, 1-propanol and the like.
Specific compounds of aldehydes include formaldehyde, acetaldehyde, 2-methylpropanal, 3-methylbutanal and the like.
Specific examples of the ketones include acetone, MEK, MIBK, 3,3-dimethyl-2-butanone and the like.
Specific compounds of carboxylic acids include acetic acid, isovaleric acid, 2-methylpropanoic acid, 2,2-dimethylpropanoic acid and the like.

(Easy needle piercing property)
What is easy needle piercing property? For example, in a gas adsorption package for packaging a liquid content filled with water for a water server, when the gas adsorption package is set in the water server, the needle equipped in the water server is the liquid content. It is an aptitude that the work when piercing and penetrating from the easy piercing sealant layer side of the gas adsorption package for packaging is easy, and it is quantified by measuring the piercing strength.
The piercing strength is preferably measured by preparing a strip-shaped test piece having a size of 120 mm × 80 mm from a laminate for packaging liquid contents and measuring by a method according to JIS Z 1707 1997.
The piercing strength is preferably 2N or more and 10N or less, and more preferably 2.5N or more and 9.5N or less. If it is smaller than the above range, through holes may be inadvertently generated during the packaging process, during transportation of the package, or during storage. May get worse.

(Low TOC elution)
The low TOC elution property means that the amount of TOC (Total Organic Carbon, total organic carbon) eluted from the laminate for packaging the liquid contents to the liquid contents is small.
TOC indicates the concentration of the total amount of organic substances (organic carbon bodies) that can be oxidized in water by the concentration of carbon amount, and is used as one of the typical water quality indexes. It is standardized by organic carbon (TOC) automatic measuring instrument) and the like.
In the present invention, the low TOC elution property is indicated by the change in the TOC concentration of water as the liquid content in the gas adsorption package for packaging the liquid content before and after the medium- to long-term storage.
The TOC increase concentration (the amount of increase in the TOC concentration) in the contents of the gas adsorption package for packaging liquid contents is preferably 0.05 ppm or more and 1.5 ppm or less.
In order to achieve a low TOC increase concentration in the above contents, it is necessary that the concentration of the elution TOC contained in the laminate for packaging the liquid contents is low, and the elution property contained in the laminate is required. The TOC concentration is preferably 1.5 ppm or more and 250 ppm or less.
It is technically difficult to obtain a product lower than the above range, and it is difficult to show a significant difference in practical effect. If it is higher than the above range, there is a possibility that the long-term odor resistance changeability to the liquid contents when the package is prepared is inferior.
The concentration of elution TOC contained in the above-mentioned laminate for packaging liquid contents is such that the gas adsorption sealant layer becomes an inner layer and comes into direct contact with the liquid contents using the laminate for packaging liquid contents. The pouch prepared as described above was filled with water as a liquid content and measured.

The organic compounds detected as the TOC elution amount are hydrocarbons, alcohols, aldehydes, ketones, and carboxylic acids, and hydrocarbons are particularly abundant.

Here, when the total amount of the elution TOC contained in the pouch prepared by using the laminate for packaging the liquid contents is eluted in 1000 g of the filling water, the increased concentration of the TOC in the filling water is as follows. It is calculated.
Pouch specific density: S [g / cm ³ ]
Pouch size: 15 cm x 44 cm x 50 μm thickness Pouch weight: W = 15 x 44 x 50 x 10 ^-4 x 2 x S = 6.6 x S [g]
Concentration of elution TOC contained in pouch: C [ppm]
Then
Total weight of elution TOC contained in pouch = C × W [g]
Since this elutes in 1000 g of water,
Increased concentration of TOC in filled water = C × W / 1000 = C × 6.6 × S × 10 ^-3 [ppm]
For example, when the specific gravity of the laminate for packaging the liquid contents constituting the pouch is 0.92 and the concentration of the elution TOC contained is 1.7 ppm,
The increase concentration of TOC in the filling water ^{is calculated as 1.7 × 6.6 × 0.92 × 10 -3} = 0.01 [ppm].

As a specific method for determining the increased concentration of TOC, for example, the above pouch is filled with 1000 g of distilled water at 40 ° C. to 80 ° C. and stored at 25 ° C. to 50 ° C. for several days to 4 weeks. The TOC concentration of the filled water can be measured with a total organic carbon meter or HS-GC, and the TOC concentration of untreated distilled water can be subtracted as a blank.
In the present invention, a pouch (15 cm × 44 cm) is prepared as a package using a laminate for packaging liquid contents, and 1000 g of water at 65 ° C. (distilled water for high performance liquid chromatography, genuine chemistry) is filled. To prepare a liquid filler for gas adsorption packaging for liquid content packaging, store it at 35 ° C for 2 weeks, and then measure the TOC concentration of the filled water with a TOC-L total organic carbon meter manufactured by Shimadzu Corporation. Is used as a standard method to determine the increased concentration of TOC.
Then, from the obtained TOC increase concentration of the filling water, the mass part of the filling water and the mass part of the laminate for packaging the liquid contents, the elution TOC concentration contained in the laminate for packaging the liquid contents is determined. Can be calculated.
In addition, the liquid content having a high TOC concentration can be sensually perceived as having a strong odor.
In the present invention, the TOC concentration of the liquid content can be reduced by adsorbing the TOC by the gas adsorbent contained in the laminate.

(Aptitude for filling machine)
Filling machine suitability means manufacturing that does not cause defects such as heat seal defects and pinholes in the process using a filling machine that continuously manufactures a gas adsorption package for packaging liquid contents and fills the contents. It is aptitude.

(Low wrinkle occurrence)
Low wrinkle generation means that the gas adsorption package for packaging liquid contents filled with liquid contents is unlikely to generate wrinkles due to external force in any of the packaging process, filling process, transportation process, and storage process. It is performance.
In order to prevent the occurrence of the wrinkles, it is effective to reduce the rigidity of the laminate for packaging the liquid contents, and in order to reduce the rigidity, the thickness of the laminate for packaging the liquid contents is increased. It is effective to make it thinner and to reduce the elastic modulus of the laminate for packaging liquid contents.

(Pinhole resistance)
Pinhole resistance refers to the performance of a laminate for packaging liquid contents that is unlikely to generate pinholes during the packaging process or during transportation of the package.
The pinhole referred to here is a through hole and a very local partial peeling in the gas adsorption package for liquid content packaging, and is used for liquid content packaging constituting the gas adsorption package for liquid content packaging. This may be intra-layer cohesive failure or peeling of the interlayer interface in the laminate, or peeling of the heat-sealed interface between laminates for packaging liquid contents.
By improving the pinhole resistance, the resistance to water leakage of the contents (water leakage resistance) is improved.
Specifically, the pinhole resistance is preferably such that the number of pinholes generated after 5000 times of gelboflex at 23 ° C. is 0, or 1 or more and 160 or less.
It is presumed that pinholes are generated by the progress of fatigue fracture due to local repeated bending due to vibration.

(Sliding)
The above-mentioned local repeated bending related to pinhole resistance is caused by the stress generated when the laminate or the package comes into contact with the packaging equipment or the packaging container, or the laminate or the packages, but is easily formed as an outer layer. If the static friction coefficient of the piercing sealant layer is small and the slidability is excellent, bending can be reduced by sliding, and pinhole resistance can be improved.
The coefficient of static friction of the easy-to-pierce sealant layer is preferably 0.04 or more and 0.3 or less, and more preferably 0.05 or more and 0.28 or less. It is difficult to obtain a static friction coefficient smaller than the above range, and there is a risk that peeling may easily occur at the interface of the sealant layer that is easily pierced between the laminates. If the static friction coefficient is larger than the above range, the slidability May be insufficient.

(Drop resistance)
Drop resistance refers to the performance that a gas adsorption package for packaging a liquid content filled with a liquid content is unlikely to be damaged by an impact such as dropping during transportation or cargo handling work.
The evaluation of the drop resistance in the present invention is performed when 4.7 L of water is filled in a pouch having a size of 350 mm × 330 mm and which is made of a laminate for packaging liquid contents, and vertical drop is repeated 5 times from a height of 1 m. It was confirmed that the bag was broken and that there was no liquid leakage.

(High transparency)
High transparency means that the transmittance of visible light is high and there is little fogging.
The high transparency makes it easy to visually identify and detect abnormalities in the liquid contents filled in the gas adsorption package for packaging liquid contents, and also for packaging liquid contents. It becomes easy to detect anomalies in the laminated body.
Transparency is preferably evaluated by measuring the haze (cloudiness) value (%) by a method according to JIS K 7361-1: 1997.
The haze value is preferably 35% or less. If it is larger than the above range, the transparency tends to be insufficient. The lower limit is not particularly limited, and the higher the transparency, the more preferable. The lower limit value may be 0%, but a value in the range of 3% to 15% or 5 to 10% may be a lower limit value in consideration of practical effects and manufacturing suitability.

The details of each layer constituting the laminate for packaging the liquid contents are as follows.
<Easy piercing sealant layer>
The easy-piercing sealant layer is a layer that imparts heat-sealing property and easy-needle piercing property to the laminate for packaging liquid contents of the present invention, and is rubbed with easy-piercing polyethylene, a flexibility-imparting resin, and the like. Contains a resistance reducing agent. The easily piercing polyethylene and / or the flexibility-imparting resin preferably has heat-sealing properties. Further, a general-purpose heat-sealing resin other than these may be contained.

Since polyethylene-based resin is resistant to sterilization treatment using ultraviolet irradiation and heating and has the property of being difficult to decompose, if a large amount of polyethylene-based resin is contained in the easy-to-pierce sealant layer, an odor component will be generated. And the increase in TOC concentration of the liquid content can be suppressed, which is preferable. In addition, many polyethylene-based resins have excellent heat-sealing properties.
Therefore, the easily piercing polyethylene can impart easy needle piercing property and heat sealing property to the easy piercing sealant layer, and further, it can impart low odor property and reduction of increase in TOC concentration. can.

The content of the easily piercing polyethylene in the easily piercing sealant layer is preferably 60% by mass or more and 95% by mass or less, and more preferably 75% by mass or more and 94% by mass or less. If it is less than the above range, the easy needle piercing property of the laminate for packaging liquid contents may be insufficient, and if it is more than the above range, the pinhole resistance may be lowered.

Then, the flexibility-imparting resin can impart pinhole resistance, and further, if a polyethylene-based flexibility-imparting resin is used, heat-sealing property, low odor property, and reduction of increase in TOC concentration are imparted. be able to.
The content of the flexibility-imparting resin in the easily piercing sealant layer is preferably 3% by mass or more and 40% by mass or less, more preferably 4% by mass or more and 25% by mass or less, and 5% by mass or more and 20% by mass or less. Is even more preferable. If it is less than the above range, the easy-to-pierce sealant layer may be too hard and the pinhole resistance may decrease. If it is more than the above range, the rigidity of the laminate for packaging liquid contents becomes too small and wrinkles occur. It may be easier to do.

As the friction resistance reducing agent, a slip agent and / or an anti-blocking agent can be contained.
The content of the frictional resistance reducing agent in the easily piercing sealant layer is preferably 0.05% by mass or more and 2% by mass or less, and more preferably 0.1% by mass or more and 1.5% by mass or less. If it is less than the above range, the frictional resistance reducing effect is unlikely to be exhibited, and if it is more than the above range, the frictional resistance reducing effect does not change so much. There is a risk that the interlayer adhesiveness in the laminate will decrease.
Further, the mass ratio of the anti-blocking agent / slip agent is not particularly limited, and a publicly known ratio is possible and can be determined according to the characteristics of the laminate, but 1.5 / 1 to 15/1 is preferable. Preferably, 2/1 to 12/1 is more preferable. Within the above range, the effect of the slip agent and the effect of the anti-blocking agent are well-balanced, and a good frictional resistance reducing effect can be easily obtained.
Alternatively, the content of the antiblocking agent in the easily piercing sealant layer is preferably 0.05% by mass or more and 1.5% by mass or less, and more preferably 0.1% by mass or more and 1% by mass or less. If it is less than the above range, the effect of the anti-blocking agent is difficult to be exhibited, and if it is more than the above range, the effect of reducing frictional resistance does not change so much. There is a risk that the interlayer adhesiveness in the laminate will decrease.
Alternatively, the content of the slip agent in the easily piercing sealant layer is preferably 0.005% by mass or more and 0.2% by mass or less, and more preferably 0.01% by mass or more and 0.15% by mass or less. If it is less than the above range, the effect of the slip agent is unlikely to be exhibited, and if it is more than the above range, the effect of reducing frictional resistance does not change so much. There is a risk that the interlayer adhesiveness in the laminate will decrease.

Since the easy-piercing sealant layer is the layer that the needle first comes into contact with when the needle is pierced, the easy-needle piercing property can be adjusted by the thickness of the easy-piercing sealant layer.
The thickness of the easy-piercing sealant layer is preferably 20 μm or more and 40 μm or less in order to have a good balance between heat-sealing property and easy-needle piercing property. If it is thinner than the above range, the heat sealability may be insufficient, and if it is thicker than the above range, the needle piercing property may be inferior.

The easy-piercing sealant layer may be formed by a known method. For example, the resin constituting the easy-piercing sealant layer may be melted and formed on another layer by (co) extrusion, a co-extrusion inflation method or the like. Therefore, the easy piercing sealant layer may be formed and laminated with another layer at the same time. Alternatively, the film is once formed by a film-forming method that has been conventionally used such as an extrusion method, a cast molding method, a T-die method, a cutting method, and an inflation method, and is laminated via an adhesive or the like to form the film. Can be done.
The method for producing the film may be any of the above methods, but the inflation method is preferable.
The film may be unstretched, but it can also be used with improved strength, dimensional stability, and heat resistance by stretching in the uniaxial or biaxial directions by, for example, a tenter method or a tubular method.
For example, a stretched film stretched in the biaxial direction is vertically stretched 2 to 4 times by a roll stretching machine at 50 to 100 ° C., and further laterally stretched 3 to 5 times by a tenter stretching machine in an atmosphere of 90 to 150 ° C. It can be obtained by heat treatment in an atmosphere of 100 to 240 ° C. with the same tenter. Further, the stretched film may be simultaneously biaxially stretched or sequentially biaxially stretched.
Among the above, it is particularly preferable to use a non-stretched single layer film or a non-stretched multilayer film.

The easy-to-pierce sealant layer may be composed of one layer, may have a multi-layer structure of two or more layers having the same and / or different composition, and may be made of easy-to-penetrate polyethylene, a flexibility-imparting resin, and friction. It may contain a layer that does not contain any one or more of the resistance reducing agents.
When the easy-to-pierce sealant layer has a multi-layer structure, for example, there may be two or more layers having different types and contents of the easy-to-penetrate polyethylene and / or the flexibility-imparting resin, and a layer having a high heat-sealing property. Is included in the outer surface and / or inner surface of the easily pierced sealant layer, so that high interlayer adhesion strength and / or high heat sealability can be obtained.

[Easy piercing polyethylene]
Easy-piercing polyethylene is polyethylene that has heat-sealing properties and is excellent in easy-needle piercing properties.
Specific examples of easy-to-pierce polyethylene include low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), linear (linear) low-density polyethylene (LLDPE), and ethylene-vinyl acetate. Copolymers, ethyl ethylene-ethyl acrylate copolymers, ethylene-acrylic acid copolymers, ethylene-methacrylic acid copolymers, ethylene-methylmethacrylic acid copolymers, ethylene-propylene copolymers and mixtures of their resins The present is mentioned, but the present invention is not limited to these resins.

Among the above, LLDPE is preferable, and C4-LLDPE is more preferable as the easily piercing polyethylene in the present invention.
C4-LLDPE is a kind of LLDPE composed of a copolymer of ethylene and 1-butene, and is a molecule having a side chain having 4 carbon atoms derived from 1-butene in the main chain of LLDPE derived from ethylene. It is a structure.
C4-LLDPE has a relatively low tensile impact strength, tensile strength, and tensile elastic modulus because the side chain is shorter and the MFR is lower than that of C6-LLDPE and C8-LLDPE. It is soft and has excellent easy needle piercing property, and can impart excellent easy needle piercing property to the laminated body.

The density of the easily piercing polyethylene is not particularly limited, and polyethylene of various densities can be used. However, in order to have excellent pinhole resistance, 0.90 g / cm ³ or more and 0.935 g / cm ³ or less is preferable.
The MFR of the easily piercing polyethylene is preferably 1 g / 10 minutes or more, 10 g / 10 minutes or less, and more preferably 3 g / 10 minutes or more and 7 g / 10 minutes or less. As long as the MFR is within the above range, good MFR can be maintained and good film-forming property and adhesiveness can be exhibited even when mixed with a flexibility-imparting resin or a friction resistance reducing agent.
The easily piercing polyethylene is preferably resistant to sterilization treatment using ultraviolet irradiation or heating, has excellent low odor, and can reduce an increase in TOC concentration.

<Gas adsorption sealant layer>
The gas adsorption sealant layer is a layer that imparts heat-sealing property, gas adsorption property, and low elution property to the laminate for packaging the liquid content of the present invention, and is a low-eluting resin, a flexibility-imparting resin, and a gas. Contains an adsorbent. The low-eluting resin and / or the flexibility-imparting resin preferably has a heat-sealing property. Further, a general-purpose heat-sealing resin other than these may be contained.
Since polyethylene-based resin is resistant to sterilization treatment using ultraviolet irradiation and heating and has the property of being difficult to decompose, if a large amount of polyethylene-based resin is contained in the gas adsorption sealant layer, gas components may be generated. It is preferable because it can suppress an increase in the TOC concentration of the liquid content. In addition, many polyethylene-based resins have excellent heat-sealing properties.
Therefore, the low-eluting resin can impart low-eluting property and heat-sealing property to the gas adsorption sealant layer, and further can impart low odor property and reduction of increase in TOC concentration.

The content of the low-eluting resin in the gas adsorption sealant layer is preferably 35% by mass or more and 97% by mass or less. If it is less than the above range, the rigidity of the laminate for packaging liquid contents may become too small and wrinkles may easily occur. If it is more than the above range, the easily piercing sealant layer is too hard and has pinhole resistance. May decrease.

Then, the flexibility-imparting resin can impart pinhole resistance, and further, if a polyethylene-based flexibility-imparting resin is used, heat-sealing property, low odor property, and suppression of increase in TOC concentration can be imparted. Can be done.
The content of the flexibility-imparting resin in the gas adsorption sealant layer is preferably 2% by mass or more and 25% by mass or less, and more preferably 5% by mass or more and 22% by mass or less. If it is less than the above range, the gas adsorption sealant layer may be too hard and the pinhole resistance may be lowered. If it is more than the above range, the rigidity of the laminate for packaging liquid contents becomes too small and wrinkles occur. It may be easier.

The laminate for liquid content packaging of the present invention contains a gas adsorbent in the gas adsorption sealant layer in contact with the content, so that the concentration of gas components in the content container of the gas adsorption package for liquid content packaging can be increased. , Can be lowered efficiently.
The content of the gas adsorbent in the gas adsorption sealant layer is preferably 0.3% by mass or more and 15% by mass or less, and more preferably 0.5% by mass or more and 14% by mass or less.
If it is less than the above range, the gas adsorption effect is unlikely to be exhibited, and if it is more than the above range, the film forming property may be deteriorated.

The gas adsorption sealant layer can contain a smaller amount of slip agent, anti-blocking agent, antioxidant, solvent, and other additives, but it is an additive that is likely to increase the elution amount of organic substances when heated. It is preferable to limit the use to prevent oxidation due to high temperature.

Since the gas adsorption sealant layer is a layer in contact with the content accommodating portion and the contents of the gas adsorption package for liquid content packaging, the gas adsorption property is adjusted by the thickness of the gas adsorption sealant layer to reduce odor. Low TOC elution can be regulated.
The thickness of the gas adsorption sealant layer is preferably 40 μm or more and 70 μm or less in order to have a good balance between heat sealability, gas adsorption property and low TOC elution property. If it is thinner than the above range, the heat sealability and / or gas adsorption property may be insufficient, and if it is thicker than the above range, the low TOC elution property may be inferior.

The gas adsorption sealant layer may be formed by a known method. For example, the resin constituting the gas adsorption sealant layer may be melted and formed by (co) extrusion on another layer, or by a coextrusion inflation method or the like. The gas adsorption sealant layer may be formed and laminated with another layer at the same time. Alternatively, the film is once formed by a film-forming method that has been conventionally used such as an extrusion method, a cast molding method, a T-die method, a cutting method, and an inflation method, and is laminated via an adhesive or the like to form the film. Can be done.
The method for producing the film may be any of the above methods, but the inflation method is preferable.
The film may be unstretched, but it can also be used with improved strength, dimensional stability, and heat resistance by stretching in the uniaxial or biaxial directions by, for example, a tenter method or a tubular method.
For example, a stretched film stretched in the biaxial direction is vertically stretched 2 to 4 times by a roll stretching machine at 50 to 100 ° C., and further laterally stretched 3 to 5 times by a tenter stretching machine in an atmosphere of 90 to 150 ° C. It can be obtained by heat treatment in an atmosphere of 100 to 240 ° C. with the same tenter. Further, the stretched film may be simultaneously biaxially stretched or sequentially biaxially stretched.
Among the above, it is particularly preferable to use a non-stretched single layer film or a non-stretched multilayer film.

The gas adsorption sealant layer may be composed of one layer, may have a multi-layer structure of two or more layers having the same and / or different composition, and may not contain a gas adsorbent and / or a low-eluting resin. It may contain layers.
When the gas adsorbent sealant layer has a multi-layer structure, for example, there may be two or more layers having different types and contents of the gas adsorbent, and a layer having a low gas adsorbent content may be formed on the outer surface of the gas adsorbent sealant layer and the outer surface of the gas adsorbent sealant layer. By including it in / or the inner surface, high interlayer adhesion strength and / or high heat sealability can be obtained.

(Low elution resin)
The low-eluting resin means a resin in which the amount of TOC (Total Organic Carbon, total organic carbon) eluted from the resin to the liquid content is small, and the amount of elution varies depending on the shape of the resin, the thermal history, and the like.
By incorporating a low-eluting resin having heat-sealing property into the gas adsorption sealant layer in contact with the liquid content, the gas adsorption sealant layer is imparted with heat-sealing property, and the gas adsorption package for packaging the liquid content of the present invention can be used. It is possible to reduce the concentration of organic substances eluted in the filled liquid contents and suppress the change in odor of the liquid contents.

The concentration of the eluted TOC contained in the low-eluting resin is preferably 1.5 ppm or more and 250 ppm.
It is difficult to prepare a product lower than the above range, and it is difficult to show a significant difference in practical effect. If it is higher than the above range, there is a possibility that the long-term odor resistance changeability to the liquid contents when the package is prepared is inferior.
The concentration of the elution TOC contained in the above-mentioned low-eluting resin is a value measured in the film-formed low-eluting resin. The reason for measuring in the filmed state is that the low-eluting resin may increase the amount of TOC eluted by being given various thermal histories when it is formed into a film such as the formation of a sealant layer. This is a consideration, and it is preferable to give a corresponding thermal history at the time of actual film formation or lamination.

As a low-eluting resin having heat-sealing properties, it has excellent heat-sealing properties, is resistant to sterilization treatment using ultraviolet irradiation or heating, and is difficult to be decomposed. Therefore, it is a polyethylene-based resin (low-eluting property). Polyethylene resin) is preferable.
The low-eluting polyethylene resin originally contains a small amount of elution TOC, is resistant to sterilization treatment using ultraviolet irradiation or heating, and is difficult to be decomposed. Therefore, the liquid content after the sterilization treatment It is possible to reduce the amount of gas components and elution TOC generated from the laminate for packaging.
In general, some polyethylenes have a lower limit of density ^{less than 0.90 g / cm 3} , an upper limit of ^{about 0.96 g / cm 3} , and a density of low-density polyethylene is 0. .910g / cm ³ or more and less than 0.930 g / cm ^3, the density of the linear low density polyethylene 0.910 g / cm ³ or more, but is 0.925 g / cm ³ or less, low elution in the present invention It is preferable to use polyethylene having a density of 0.90 g / cm ³ or more and 0.94 g / cm ^{3 or less.}
Low-eluting polyethylene having a density in the above range tends to reduce the amount of organic matter eluted.

The MFR (melt flow rate) of the low-eluting polyethylene resin is preferably 1 g / 10 minutes or more, 10 g / 10 minutes or less, 1.5 g / 10 minutes or more, and 7 g / 10 minutes or less. As long as the MFR is within the above range, good MFR can be maintained and good film-forming property and adhesiveness can be exhibited even when mixed with a flexibility-imparting resin or a gas adsorbent.

Specific examples of polyethylene types of low-eluting polyethylene-based resin include low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), linear (linear) low-density polyethylene (LLDPE), and the like. Ethethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-methylmethacrylic acid copolymer, ethylene-propylene copolymer, etc. Examples include, but are not limited to, low elution and mixtures of their resins.
Among the above, linear low density polyethylene (LLDPE) is preferable, and one or more selected from the group consisting of C4-LLDPE, C6-LLDPE, and C8-LLDPE is more preferable, and C6-LLDPE is more preferable. More preferred.
Here, C4-LLDPE is a linear low-density polyethylene composed of a copolymer of ethylene and 1-butene, and C6-LLDPE is composed of ethylene and 1-hexene and / or 4-methyl-1-pentene. It is a linear low density polyethylene composed of the copolymer of ethylene, and C8-LLDPE is a linear low density polyethylene composed of a copolymer of ethylene and 1-octene.
Each molecular structure has 4 and 6 carbon atoms derived from 1-butene, 1-hexene and / or 4-methyl-1-pentene and 1-octene on the main chain of ethylene-derived LLDPE, respectively. It has a molecular structure in which 8 or 8 side chains are present.

In order to keep the elution TOC amount of the resin low, for example, when producing the resin, it is necessary to reduce the residual amount of unreacted raw materials, the amount of low molecular weight products and by-products, and to remove the polymerization catalyst. Is. Specifically, the purity of raw materials can be improved, conditions such as reaction temperature and pressure can be precisely controlled, and unreacted raw materials, low molecular weight products, by-products, and polymerization catalysts can be removed by distillation or washing. Examples thereof include a method of preventing oxidation due to contact with oxygen in the air at a high temperature.
Another method is to limit the use of additives that are likely to increase the amount of elution TOC when pelletizing or filming the produced resin, and to prevent oxidation due to high temperature. Specific additives include lubricants, antioxidants, antiblocking agents, solvents, and the like.
The present invention is not limited to the above method.

[Gas adsorbent]
In the present invention, the gas adsorbent contains hydrophobic zeolite. Then, the chemically adsorbent-supported inorganic porous body can be further contained.
The content of the gas adsorbent in the gas adsorption sealant layer is preferably 0.3% by mass or more and 15% by mass or less. The content of this gas adsorbent is the total amount of the hydrophobic zeolite and the chemical adsorbent-supported inorganic porous body when they are contained.
The content of the hydrophobic zeolite in the gas adsorption sealant layer is preferably 0.3% by mass or more and 15% by mass or less. If it is less than the above range, the gas adsorption effect is unlikely to be exhibited, and if it is more than the above range, the film forming property may be deteriorated.
When the chemical adsorbent-supported inorganic porous body is contained, the content of the chemical adsorbent-supported inorganic porous body in the gas adsorption sealant layer is preferably 0.1% by mass or more and 10% by mass or less. If it is less than the above range, it is difficult to exhibit the gas adsorption effect due to the inclusion of the chemical adsorbent-supported inorganic porous body, and if it is more than the above range, the film-forming property may be deteriorated.

(Hydrophobic zeolite)
In the present invention, the hydrophobic zeolite used as the gas adsorbent preferably has a SiO ₂ / Al ₂ O ₃ molar ratio of 30/1 to 10000/1. When the molar ratio is in the above range, the balance between hydrophobicity and pore size is excellent, and good gas adsorption can be obtained.
The hydrophobic zeolite maintains the adsorption effect of the gas component even when the laminate of the present invention is exposed to 230 ° C. or higher.
The hydrophobic zeolite may have any outer shape such as spherical, rod-shaped, or elliptical, and may have any form such as powder, lump, or granular, but is uniform when dispersed in the resin. From the viewpoint of dispersibility, kneading characteristics, film forming property, etc., the powder form is preferable.

In the present invention, the average particle size of the hydrophobic zeolite can be appropriately selected depending on the intended use, but the average particle size is preferably 0.01 μm to 15 μm. Here, the average particle size is a value measured by a dynamic light scattering method.
When the average particle size is smaller than the above range, the hydrophobic zeolite tends to aggregate and the dispersibility tends to decrease. Further, when the average particle size is larger than the above range, the film-forming property of the layer containing the hydrophobic zeolite tends to be inferior, so that it tends to be difficult to add a large amount of hydrophobic zeolite, and the surface area also increases. Since it is reduced, there is a possibility that a sufficient deodorizing effect cannot be obtained.

Since hydrophobic zeolite is hydrophobic, it is difficult to adsorb highly polar water molecules, etc., and conversely, it has low polarity compatibility with gas components, hydrophobic gases, and lipophilic gases (including solvent-based gases). Is high and it is easy to adsorb these. That is, it is also excellent in the function of adsorbing a gas component having no functional group. Further, the zeolite surface is basic due to the effects of alkali metals such as Ca, Na and K and alkaline earth metals existing on the zeolite surface, and acid gas is easily adsorbed by the neutralization reaction.

(Chemisorbent-supported inorganic porous material)
In the present invention, the chemical adsorbent-supported inorganic porous body is one in which a chemical adsorbent is supported on the inorganic porous body, and is particularly excellent in the function of adsorbing a gas component having a functional group.
In the present invention, the chemical adsorbent used for the chemically adsorbent-supporting inorganic porous body is a compound having a reactive functional group that chemically reacts with an odorous substance and binds to the inorganic porous body, and can be supported on the inorganic porous body. Is.
More specifically, it is a compound having a functional group having a reactivity to bind to aldehydes, ketones, carboxylic acids or alcohols, and examples of such a compound include a compound containing an amino group and a compound having a hydroxyl group. And so on.
As a supporting method, a known or conventional supporting method can be applied. For example, an inorganic porous body may be impregnated with a solution containing a chemical adsorbent described below and dried to support the inorganic porous material. can.
In the present invention, by using the chemical adsorbent-supporting inorganic porous body, the adsorption capacity of the chemical adsorbent per unit mass can be significantly enhanced, and the chemical adsorbent and the chemical adsorbent-supporting inorganic porous body in the laminate can be significantly enhanced. The content rate can be reduced. In addition, physical adsorption characteristics for the pores of the inorganic porous body can be expected.
As a result, high adhesive strength and sealing strength can be obtained, and the excellent adhesiveness, coatability and film forming property required for the adhesive layer can be maintained, and the excellent heat sealing property and film forming property required for the sealant layer can be maintained. Can be retained.

The chemical adsorbent-supported inorganic porous body preferably contains one or more elements selected from the group of copper, zinc, silver, platinum, iron, and cobalt.
Further, the chemisorbent-supported inorganic porous body may have an arbitrary outer shape such as a spherical shape, a rod shape, or an elliptical shape, and may have any shape such as a powder shape, a lump shape, or a granular shape. From the viewpoint of uniform dispersibility, kneading characteristics, etc., the powder form is preferable.

As the chemical adsorbent-supported inorganic porous material, an inorganic porous body having an arbitrary average particle size can be appropriately selected depending on the intended use, but in the present invention, an average particle size of 0.01 μm to 15 μm is particularly preferable, and 0 .1 μm to 13 μm is more preferable, and 1 μm to 12 μm is even more preferable. Here, the average particle size is a value measured by a dynamic light scattering method.
When the average particle size is smaller than the above range, the chemically adsorbent-supported inorganic porous material tends to aggregate and the dispersibility tends to decrease.
Further, when the average particle size is larger than the above range, the film-forming property is inferior, so that it tends to be difficult to contain a large amount of the chemically adsorbent-supported inorganic porous material, and there is a possibility that a sufficient adsorption effect cannot be obtained. Occurs.
Specific examples of commercially available products include NS-241 and NS-231 (amino group-containing compound-supported inorganic porous material) manufactured by Toa Synthetic Co., Ltd., and Dashlite M (amino group-containing compound) manufactured by Sinanen Zeomic Co., Ltd. A supported inorganic porous body), Kesmon NS-80E (supported inorganic porous body) and the like can be used as a suitable gas adsorbent in the present invention.

Since the chemical adsorbent-supported inorganic porous body is chemically adsorbed, the odorous substance once adsorbed is difficult to be desorbed, and the odor can be efficiently adsorbed.
Furthermore, since the odorous substance binds to a specific functional group of the chemical adsorbent, it is not easily affected by various substances that reduce the odor-adsorbing ability, such as water vapor.

(Amino group-supported inorganic porous material)
The amino group-supported inorganic porous body is an inorganic porous body carrying an amino group on its surface, and can chemically adsorb an odorous substance that chemically reacts with the amino group.
The amino group-supported inorganic porous body can be produced, for example, by using a compound containing an amino group.
Examples of the compound containing an amino group include alkylamines, cyclic amines, polyamines, and alcohol amines. Specific examples thereof include ethylenediamine, tetramethylenediamine, metaphenylenediamine, diethylenetriamine, triethylenetriamine, tetraethylenepentamine, ethanolamine, piperazine and piperidine.
The amino group-supported inorganic porous body has excellent adsorption performance for aldehydes and ketones.
Aldehydes and ketones chemically react with amino groups by Schiff reaction and are adsorbed.

(Hydroxy group-supported inorganic porous material)
The hydroxyl group-supported inorganic porous body is an inorganic porous body that supports a hydroxyl group on its surface, and can chemically adsorb an odorous substance that chemically reacts with the hydroxyl group.
The hydroxyl group-supported inorganic porous body can be produced, for example, by using a compound containing a hydroxyl group.
Examples of the compound containing a hydroxyl group include metal hydroxides. Specific examples thereof include sodium hydroxide, potassium hydroxide, magnesium hydroxide, iron hydroxide and the like.
The hydroxyl group-supported inorganic porous body has excellent adsorption performance for carboxylic acids and amines.

(Inorganic porous material used for chemical adsorbent-supported inorganic porous material)
In the present invention, any inorganic compound having a large number of pores on the surface thereof can be used as the inorganic porous body used for the chemical adsorbent-supporting inorganic porous body, and for example, zeolite, silicon dioxide, silicate, and the like can be used. Inorganic phosphates such as activated charcoal, titania, calcium phosphate, alumina, aluminum hydroxide, magnesium hydroxide, and mixtures thereof can be mentioned, and in particular, porous pore size effective for the molecular size and cluster size of the substance to be adsorbed. It is preferable to apply aluminum hydroxide, zeolite, or silicate from the viewpoint of having a state and safety.
In the above, the zeolite is preferably hydrophobic, and more preferably the SiO ₂ / Al ₂ O ₃ molar ratio is 400/1 to 10000/1.
In particular, it is preferable to apply aluminum hydroxide, zeolite, or silicate from the viewpoint of having a porous state having a pore size effective with respect to the molecular size and cluster size of the substance to be adsorbed and from the viewpoint of safety.

The outer shape of the inorganic porous body may be any outer shape such as spherical, rod-shaped, or elliptical, and may be any shape such as powder, lump, or granular, but it carries a chemical adsorbent. After forming an inorganic porous body carrying a chemical adsorbent, it is preferably in the form of powder from the viewpoints of film forming property, uniform dispersion, kneading characteristics and the like.
As the inorganic porous body, an arbitrary average particle size can be appropriately selected depending on the intended use, but in order to achieve the average particle size of the above-mentioned chemical adsorbent-supported inorganic porous body, the average particle size is 0. Those of 01 μm to 15 μm are preferable, those of 0.1 μm to 13 μm are more preferable, and those of 1 μm to 12 μm are further preferable.

(Chemisorbent used for inorganic porous materials supported by chemical adsorbent)
In the present invention, the chemical adsorbent used for the chemical adsorbent-bearing inorganic porous material causes a chemical reaction with an elution organic substance or a gas substance generated by decomposition of the resin during sterilization treatment using ultraviolet irradiation or heating. It is a compound having a reactive functional group to be bonded to the above-mentioned inorganic porous body and can be supported on the above-mentioned inorganic porous body.
More specifically, a functional group having reactivity to bind to one or more selected from the group consisting of various aldehydes, ketones, carboxylic acids and the like generated during sterilization treatment using ultraviolet irradiation or heating. It is a compound having.

Examples of such compounds include compounds containing an amino group, for example, polyamines such as alkylamines and tetramethylenediamine, and compounds having basic functional groups such as ethanolamine, piperidine and aquatic groups, for example, sodium hydroxide and hydroxylated compounds. Hydroxide such as potassium, magnesium hydroxide, iron hydroxide, carbonate such as sodium carbonate, sodium hydrogencarbonate, calcium carbonate, hydrogen carbonate, amide group-containing compound such as 2-acrylamide-2-methylpropanesulfonic acid, etc. Can be mentioned.
In the present invention, as a chemical adsorbent exhibiting a particularly excellent adsorption effect, a compound having an amino group or an aquatic group, for example, a polyamine such as ethylenediamine, diethylenetriamine, triethylenetriamine, tetraethylenepentamine, piperazine, metaphenylenediamine, etc. Examples thereof include, but are not limited to, sodium hydroxide, potassium hydroxide, magnesium hydroxide, iron hydroxide and the like.

The adsorption mechanism of the chemical adsorbent on the substance to be adsorbed will be described in more detail with reference to the specific examples of FIGS. 4A to 4B, but the present invention is not limited thereto.
For example, when the substance to be adsorbed is an acid-based substance, as shown in FIG. 4A, the chemical adsorbent-supporting inorganic obtained by supporting, for example, a compound having an aquatic group on an inorganic porous body as a chemical adsorbent. A porous body can be used. As a result, the carboxyl group and the aquatic group cause a chemical reaction to bond with each other, and the substance to be adsorbed is adsorbed.
When the substance to be adsorbed is an aldehyde, as shown in FIG. 4B, the chemical adsorbent-supported inorganic porous body is formed by supporting, for example, a compound having an amino group on an inorganic porous body as a chemical adsorbent. The body can be used. As a result, the aldehyde group and the amino group cause a chemical reaction to bond with each other, and the substance to be adsorbed is adsorbed.

At this time, since the substance is chemically adsorbed, the substance to be adsorbed once adsorbed does not desorb, and gas adsorption can be performed efficiently.
Further, unlike the physical adsorbent in which the substance to be adsorbed and the water vapor are adsorbed on the same adsorption site, the chemical adsorbent in the present invention is a gas because the substance to be adsorbed binds to a specific functional group of the chemical adsorbent. It is not easily affected by various substances that reduce the adsorptive capacity, such as water vapor.

(Improved dispersibility by masterbatch of gas adsorbent)
The gas adsorbent may be directly mixed with other components of the gas adsorption sealant layer and melt-kneaded, but the gas adsorbent is mixed with the thermoplastic resin at a high concentration and then melt-kneaded (melt blend). A gas adsorption sealant layer of a gas adsorbent is produced by a so-called master batch method in which a master batch is prepared, mixed with other components of the gas adsorption sealant layer at a ratio according to the target content, and melt-kneaded. It is preferable to increase the dispersibility in.
By adopting the masterbatch method, the gas adsorbent can be efficiently and uniformly dispersed in the gas adsorption sealant layer even when a gas adsorbent that easily causes agglutination is used.

The mass ratio of the gas adsorbent / thermoplastic resin in the masterbatch is not particularly limited, but the ratio is preferably 3/97 to 40/60, and more preferably 5/95 to 35/65.
As a method for kneading the gas adsorbent and the thermoplastic resin, a known or conventional kneading method can be applied.
The thermoplastic resin used for the master batch can be used in a type and content within a range that does not significantly adversely affect the heat sealability, film forming property, gas adsorption property, and low elution property of the entire gas adsorption sealant layer. A resin having high compatibility with other resins such as heat-sealing resin B, low-eluting resin, and C6-LLDPE contained in the gas adsorption sealant layer and having the same degree of heat-sealing property is preferable, and they are the same. Or it may be different. Further, it may be low-eluting polyethylene.

Specific examples of the thermoplastic resin include, but are limited to, general-purpose polyethylene, polypropylene, methylpentene polymer, polyolefin resins such as acid-modified polyolefin resins, and mixtures of these resins. Instead, the type of thermoplastic resin can be selected according to the purpose.

The MFR (melt flow rate) of the thermoplastic resin is preferably 0.2 g / 10 minutes or more and 10 g / 10 minutes or less. If the MFR is in this range, melt kneading with the gas adsorbent is easy, the gas adsorbent is easily dispersed in the gas adsorbent sealant layer, and the film-forming property of the gas adsorbent sealant layer is easily maintained.

Details of the raw materials used for both the easy-piercing sealant layer and the gas adsorption sealant layer are as follows.

[Flexibility imparting resin]
In the present invention, the flexibility-imparting resin is a resin that imparts flexibility by mixing. For example, flexibility can be imparted to the easy piercing sealant layer and / or the gas adsorption sealant layer.
As the flexibility-imparting resin, it is preferable that the flexibility-imparting resin itself is soft.
The vicut softening point of the flexibility-imparting resin is preferably 35 ° C. or higher and 120 ° C. or lower, and more preferably 40 ° C. or higher and 115 ° C. or lower. If the Vicat softening point is larger than the above range, it is often difficult to show a sufficient effect of imparting flexibility at the operating temperature of the laminated body, and if the Vicat softening point is smaller than the above range, it is at the operating temperature of the laminated body. It is easy to cause stickiness.
Then, the density of the softening resins, 0.85 g / cm ³ or more, 0.905 g / cm ³ or less. If the density is higher than the above range, it is often difficult to exhibit a sufficient flexibility-imparting effect, and it is difficult to prepare a density smaller than the above range.
Further, if the elution TOC content of the flexibility-imparting resin is small, the elution TOC content of the entire laminate can be reduced, and the increase in TOC concentration of the liquid content can be suppressed.
As a specific flexibility-imparting resin, an olefin-based thermoplastic elastomer or an olefin-based plastomer is preferable, and one or two of the above can be contained.

(Olefin-based thermoplastic elastomer)
The olefin-based thermoplastic elastomer used as the flexibility-imparting resin in the present invention is a copolymer having a hard segment derived from an olefin and a soft segment derived from an olefin, and is a repeating unit derived from each olefin monomer. It is classified into a random copolymer type and a block copolymer type according to the arrangement state. One of these may be used alone, or two or more thereof may be mixed and used.
In general, the random copolymer type is relatively softer and has a lower melting point (softening point) than the block copolymer type.
Specific examples of olefin-based thermoplastic elastomers include ethylene-propylene block copolymers, ethylene / butene random copolymers, ethylene / octene block copolymers, and various cyclic olefin copolymers.

The random copolymer type olefin-based thermoplastic elastomer is an olefin-based copolymer in the case where the repeating units derived from each olefin monomer are randomly arranged.
For example, the main chain structure of an olefin-based random copolymer composed of monomer A and monomer B is represented by -A-B-A-A-B-A-B-B-A-B- or the like.

The block copolymer type olefin-based thermoplastic elastomer is a block in which several repeating units derived from one type of olefin monomer are consecutively formed, and then several repeating units derived from another type of olefin monomer are consecutively formed. It is an olefin-based copolymer when blocks are formed and arranged.
For example, the main chain structure of an olefin-based random copolymer composed of monomer A and monomer B is represented by -A-A-A-A-B-B-B-B-B-A-A-A-. NS.

(Olefin-based plastomer for flexibility-imparting resin)
The olefin-based plastomer used as the flexibility-imparting resin in the present invention has a main chain composed of one kind of monomer, but due to the influence of the side chain and the narrow molecular weight distribution, the olefin-based polymer exhibits elasticity and thermoplasticity. Is.
Examples of the olefin-based plastomer as described above include LLDPE synthesized using a metallocene catalyst having a narrow molecular weight distribution, which is called a metallocene plastomer.

[General-purpose heat-sealing resin]
General-purpose heat-sealable resins contained in the easily piercing sealant layer and / or the gas adsorption sealant layer include polyolefins, olefin-based copolymers, copolymers of olefins and vinyl compounds, and olefins and various (meth) acrylics. Copolymers with compounds, copolymers of olefins and unsaturated carboxylic acids, ionomer resins, ternary copolymer resins of olefins with various (meth) acrylic compounds and various unsaturated carboxylic acids, polyethylene terephthalate (PET) , Polyacrylonitrile (PAN) and the like. One of these may be used alone, or two or more thereof may be mixed and used.
Among the above, polyolefins and olefin-based copolymers are preferable, and olefin-based copolymers are more preferable, in terms of heat-sealing properties.

(Polyolefin)
In the present invention, the polyolefin is a resin having a main chain composed of repeating units derived from one or more types of monomers.
Examples thereof include polyethylene, polypropylene, methylpentene polymer, cyclic polyolefin resin, and the like. Examples of polyethylene include low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (MDPE), and linear (linear) polyethylene. Examples thereof include low density polyethylene (LLDPE) and metallocene polyethylene. One of these may be used alone, or two or more thereof may be mixed and used.

(Vinyl compound)
The vinyl compound is a compound having a vinyl group, and specific examples thereof include vinyl acetate and vinyl alcohol. Examples of various (meth) acrylic compounds include (meth) acrylic acid and (meth) acrylic acid ester. Can be mentioned. One of these may be used alone, or two or more thereof may be mixed and used.

(Unsaturated carboxylic acid)
The unsaturated carboxylic acid is a carboxylic acid having an unsaturated carbon-carbon bond, and specific examples thereof include maleic acid, fumaric acid, and anhydrides thereof. One of these may be used alone, or two or more thereof may be mixed and used.

[Friction resistance reducing agent]

(Slip agent)
In the present invention, a known slip agent can be used as the slip agent without particular limitation.
For example, higher fatty acid amides such as erucic acid amides, stearic acid amides, oleic acid amides, behenic acid amides, ethylene bisoleic acid amides and ethylene bisstearic acid amides, higher fatty acid esters, glyceric acid esters, and higher hydrocarbons such as paraffins. Wax, higher fatty acid wax, metal soap and the like are preferably mentioned, and in addition to these, hydrophilic silicone, silicone-grafted acrylic, silicone-grafted epoxy resin, silicone-grafted polyether, silicone-grafted polyester, etc. Examples thereof include block-type silicone acrylic copolymers and polyglycerol-modified silicones. These slip agents may be used alone or in combination of two or more.

Among the above, it is preferable to use a higher fatty acid amide, and among the higher fatty acid amides, it is more preferable to use an erucic acid amide, a stearic acid amide, and an oleic acid amide, and it is further preferable to use an erucic acid amide.

(Anti-blocking agent)
In the present invention, a known anti-blocking agent can be used for anti-blocking without particular limitation.
For example, synthetic zeolite, natural zeolite, talc, silica, diatomaceous earth, kaolin, PMMA and the like can be mentioned, and one or more selected from the group consisting of these can be used.
Among the above, it is preferable to use synthetic zeolite and talc in combination, and the mass ratio of synthetic zeolite / talc is preferably 70/30 to 95/5.

(Improved dispersibility by masterbatch of friction resistance reducing agent)
The friction resistance reducing agent may be directly mixed with other components and melt-kneaded, but the friction resistance reducing agent is mixed with a thermoplastic resin at a high concentration and then melt-kneaded (melt blended) to prepare a masterbatch. However, it is preferable to enhance the dispersibility of the friction resistance reducing agent by a so-called masterbatch method in which this is mixed with other constituent components at a ratio corresponding to the target content and melt-kneaded.
By adopting the masterbatch method, the frictional resistance reducing agent can be efficiently and uniformly dispersed even when the frictional resistance reducing agent in which aggregation is likely to occur is used.
In the masterbatch, each of the slip agent and the antiblocking agent may be individually masterbatched, or both may be contained in the masterbatch.

The mass ratio of the friction resistance reducing agent / thermoplastic resin in the masterbatch is preferably 10/90 to 70/30.
When the slip agents are individually master-batched, the mass ratio of the slip agent / thermoplastic resin is preferably 2/98 to 10/90.
When the anti-blocking agents are individually master-batched, the mass ratio of the anti-blocking agent / thermoplastic resin is preferably 10/90 to 90/10.

As a method of kneading the friction resistance reducing agent and the thermoplastic resin, a known or conventional kneading method can be applied.
The thermoplastic resin used in the masterbatch has a great adverse effect on the heat-sealing property and film-forming property of the entire content target layer, and on the content target layer's unique properties such as easy needle piercing property, gas adsorption property, and low elution property. It can be used with a type and content within the range not given.
Further, a resin having high compatibility with other resins contained in the content target layer and having the same degree of heat-sealing property is preferable, and may be the same as or different from these.

Specific examples of the thermoplastic resin include, but are limited to, general-purpose polyethylene, polypropylene, methylpentene polymer, polyolefin resins such as acid-modified polyolefin resins, and mixtures of these resins. Instead, the type of thermoplastic resin can be selected according to the purpose.

<Middle layer>
In the present invention, the intermediate layer is a layer that imparts various properties to the laminated body, and for example, it is possible to impart rigidity to the laminated body, impart gas barrier property, light-shielding property, strength, and the like.
What kind of characteristics are given is determined according to the type of contents to be packaged, mechanical strength, chemical resistance, solvent resistance, manufacturability, etc. required for physical distribution, and various materials are applied. Can be done.
The intermediate layer preferably contains a thermoplastic resin, and more preferably a resin film obtained by forming a film of the thermoplastic resin. For example, a known or commercially available film having gas barrier property, light shielding property, and high strength is used. be able to. The film may be unstretched, uniaxially stretched or biaxially stretched. A metal foil such as an aluminum foil can also be used.

When it is desired to improve the gas barrier property of the laminate, it is preferable to use a silica vapor deposition film, an aluminum oxide vapor deposition film, or an aluminum foil, and a silica vapor deposition film, an aluminum oxide vapor deposition film, or the like is formed on at least one surface of the resin film. Can be produced.
When it is desired to increase the piercing strength of the laminated body, a film having high strength can be used. Specifically, PET, polybutylene terephthalate, a thin-film vapor deposition film such as a silica vapor deposition film or an aluminum oxide vapor deposition film, or the like can be used. Is preferable.
When it is desired to improve the light-shielding property of the laminated body, it is preferable to use an aluminum foil.

Examples of the type of thermoplastic resin include polyethylene resin, polypropylene resin, cyclic polyolefin resin, polyvinyl alcohol, ethylene / vinyl alcohol copolymer, fluorine resin, polystyrene resin, and acrylonitrile-styrene copolymer (AS). Resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), polyvinyl chloride resin, fluorine resin, poly (meth) acrylic resin, polycarbonate resin, polyethylene terephthalate (PET), polyethylene naphthalate and other polyesters. Polyamide (nylon) -based resin such as based resin, polyamide 6, polyamide 11, polyamide 12, polyamide 66, polyamide 610, polyamide 6T, polyamide 6I, polyamide 9T, polyamide M5T, polyamide 6/66, polyimide-based resin, polyamide-based Various resins such as resins, polyarylphthalate resins, silicone resins, polysulfone resins, polyphenylene sulfide resins, polyether sulfone resins, polyurethane resins, acetal resins, and cellulose resins can be included.
The intermediate layer preferably contains one or more resins selected from the above, and may be composed of one layer or two or more layers having the same composition or different compositions.

The intermediate layer in the present invention preferably includes an intermediate layer that imparts appropriate rigidity to the laminated body.
As the film containing a thermoplastic resin in order to obtain an intermediate layer that imparts rigidity, a resin film containing a polyamide-based resin is preferable among the films containing the above-mentioned thermoplastic resin, and among the polyamide-based resins, polyamide 6/66 A resin film containing a copolymer and / or a polyamide 6/66/12 copolymer is more preferable.

The intermediate layer has workability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidant properties, slipperiness, releasability, flame retardancy, antifungal properties, electrical properties, strength, etc. of the laminate. Various reforming resins, plastic compounding agents, additives and the like can be contained for the purpose of improving and modifying the above. In this case, these additives may be arbitrarily contained in the intermediate layer from a very small amount to several tens of mass% depending on the purpose. In the present invention, as general additives, colorants such as lubricants, cross-linking agents, antioxidants, ultraviolet adsorbents, light stabilizers, fillers, antistatic agents, lubricants, antiblocking agents, dyes and pigments. Etc. can be arbitrarily contained.
In the present invention, as the intermediate layer, a single-layer or multi-layered film can be used by using a film-forming method such as an extrusion method, a cast molding method, a T-die method, a cutting method, or an inflation method.

The thickness of the intermediate layer can be appropriately determined by those skilled in the art according to the function of the intermediate layer and the packaging application, but is preferably 6 μm or more and 150 μm or less, more preferably 9 μm or more and 130 μm or less.
In particular, in the case of a layer that imparts rigidity using a resin film containing a polyamide resin, it is preferably 10 μm or more and 50 μm or less.

If necessary, the surface of the intermediate layer is preferably subjected to various surface treatments in advance before laminating. Examples of the surface treatment include corona treatment and ozone treatment.

<Adhesive layer>
In the present invention, between the layers of each layer and the layers within each layer constituting the laminate for packaging liquid contents,
It is also possible to provide an adhesive layer and stack them.
Further, before forming the adhesive layer, an anchor coat layer may be formed in advance on the surface of the layer to be bonded in order to improve the adhesiveness.

The adhesive (adhesive composition) forming the adhesive layer may be a thermosetting type, an ultraviolet curable type, an electron beam curable type, or the like, and may be in any form such as an aqueous type, a solution type, an emulsion type, and a dispersed type. The properties may be any of film / sheet, powder, solid, etc., and the adhesive mechanism may be a chemical reaction type, a solvent volatilization type, a thermosetting type, a thermosetting type, or the like. Any form may be used.
Further, such an adhesive includes a polyvinyl acetate-based adhesive such as polyvinyl acetate or a vinyl acetate-ethylene copolymer, or a polyacrylic composed of a copolymer of polyacrylic acid and polystyrene, polyester, polyvinyl acetate or the like. Acid-based adhesives, cyanoacrylate-based adhesives, ethylene copolymer-based adhesives consisting of copolymers of ethylene and monomers such as vinyl acetate, ethyl acrylate, acrylic acid, and methacrylic acid, cellulose-based adhesives, and polyurethane-based adhesives. Agents, polyester adhesives, polyamide adhesives, polyimide adhesives, polyolefin adhesives, amino resin adhesives made of urea resin, melamine resin, etc., phenol resin adhesives, epoxy adhesives, reactive types ( Meta) Examples thereof include an elastomer adhesive made of acrylic adhesive, chloroprene rubber, nitrile rubber, styrene-butadiene rubber, etc., a silicone adhesive, an alkali metal silicate, an inorganic adhesive made of low melting point glass, and the like.
Among the above, polyolefin-based adhesives are preferable when forming a laminate by coextrusion and film formation by an inflation method.

In one aspect of the present invention, the adhesive layer may be any of an EC (extrusion coat) adhesive, a dry laminating adhesive, a non-solvent laminating adhesive, and the like.
When an EC adhesive is used, it is not particularly limited, but for example, first, the adhesive is heated and melted, expanded and stretched in the required width direction with a T-die or the like, extruded into a curtain shape, and flowed onto the layer to be bonded. By sandwiching the adhesive layer between the rubber roll and the cooled metal roll, the adhesive layer is formed, and the adhesive layer is adhered to and laminated at the same time.

In another aspect, the adhesive layer may be formed by sand lamination. In this case, the adhesive layer can be any resin that can be melted by heating and applied in an extruder. Specifically, the resins listed as the above-mentioned thermoplastic resins having heat-sealing properties can be preferably used.

When using an adhesive for dry laminating, an adhesive dispersed or dissolved in a solvent is applied onto one film, dried, and the other film is laminated and then laminated at 30 to 120 ° C. for several hours to several hours. By aging for days, the adhesive can be cured, adhered and laminated.

When a non-solvent laminating adhesive is used, the adhesive itself is applied onto the layer to be adhered without being dispersed or dissolved in a solvent, dried, and the films forming the other layer are laminated and then laminated. The adhesive is cured and laminated by aging at ~ 120 ° C. for several hours to several days.

The dry laminating adhesive or the non-solvent laminating adhesive can be used by coating with, for example, a roll coat, a gravure roll coat, a kiss coat, etc., and the coating amount is 0.1 to 10 g / m ² (dry state). Is desirable. By setting the coating amount within the above range, good adhesiveness can be obtained.

(Anchor coat layer)
The anchor coat layer can be formed from any anchor coat agent.
Examples of the anchor coating agent include organic titanium, isocyanate (urethane), polyethyleneimine, acid-modified polyethylene, polybutadiene, polyacrylic, polyester, epoxy, polyvinyl acetate, cellulose, and others. Anchor coating agents such as, etc. can be used.

<< Gas adsorption packaging material for packaging liquid contents >>
The gas adsorption packaging material for liquid content packaging of the present invention is a packaging material produced from the laminate for liquid content packaging of the present invention, and may be the same as the laminate for liquid content packaging. If necessary, various functional layers, a printing layer, and the like can be further included.
Further, the gas adsorption packaging material for packaging the liquid contents of the present invention may be subjected to laminating processing (dry laminating or extruded laminating), bag making processing, and other post-treatment processing.
Specific examples of the gas adsorption packaging material for liquid content packaging of the present invention include a packaging material for a water server and a packaging material for a bag-in-box.

[Method of manufacturing laminate for liquid content packaging or gas adsorption packaging material for liquid content packaging]
For example, an example will be described in the case of producing a laminate (packaging material) for packaging liquid contents having a layer structure of an easily piercing sealant layer / adhesive layer / intermediate layer / adhesive layer / gas adsorption sealant layer. ..
The production method shown below is an example and does not limit the present invention.
First, a resin composition for forming each of the easily piercing sealant layer, the adhesive layer, the intermediate layer, the adhesive layer, and the gas adsorption sealant layer is prepared.
Then, the five layers of the easy-piercing sealant layer, the adhesive layer, the intermediate layer, the adhesive layer, and the gas adsorption sealant layer are co-extruded and laminated by the inflation film forming to prepare a laminate for packaging liquid contents.
In this way, a laminate for packaging liquid contents or a packaging material for liquid contents can be produced.

Lamination of each layer in the above is a laminating method used when manufacturing ordinary packaging materials, for example, a wet lamination method, a dry lamination method, a solvent-free dry lamination method, an extrusion lamination method, a T-die coextrusion molding method, and the like. It can be carried out by any method such as a co-extrusion lamination method, an inflation method, or the like.
The laminate for liquid content packaging or the gas adsorption packaging material for liquid content packaging obtained above has a chemical function, an electrical function, a magnetic function, a mechanical function, a friction / wear / lubrication function, and an optical function. It is also possible to perform secondary processing for the purpose of imparting a function, a thermal function, a surface function such as biocompatibility, and the like.
Examples of secondary processing include embossing, painting, adhesion, printing, metallizing (plating, etc.), machining, surface treatment (antistatic treatment, corona discharge treatment, plasma treatment, photochromism treatment, physical vapor deposition, chemical vapor deposition, etc.) Coating, etc.) and the like.

<< Liquid contents package >>
The liquid content package of the present invention is a package produced by packaging the liquid content using the packaging material for the liquid content of the present invention.
Specific examples of the liquid content package of the present invention include a water server package and a bag-in-box package.

[How to make a liquid content package]
As an example of a method for producing a liquid content package, a method for producing a packaging bag made of a packaging material for liquid content will be mentioned.
First, it can be produced by bending the packaging material for liquid contents or stacking two sheets so that the gas adsorption sealant layers of the packaging material for liquid contents face each other, and heat-sealing the peripheral end thereof. ..
The form of the packaging bag is, for example, side seal type, two-way seal type, three-way seal type, four-way seal type, envelope-attached seal type, gassho-attached seal type (pillow-seal type), fold-attached seal type, flat-bottom seal type, etc. Examples include a square bottom seal type and a gusset type.
As a heat sealing method, for example, a known method such as a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, or an ultrasonic seal can be applied.

<< Liquid contents >>
In the present invention, specific examples of the liquid content packaged in the liquid content package include drinking water, juices, infusion solution for drip, soy sauce, sauce, and other seasoning liquids, soup, honey, sauce, dressing, and the like. Examples include liquids in general.

Details of the raw materials used in the examples are as follows.
[Easy piercing polyethylene]
-Easy piercing polyethylene 1: UMERIT 720FT manufactured by Ube Industries, Ltd. C4-LLDPE, density 0.918 ^{g / cm 3} , MFR 4 g / 10 minutes.

[Low-eluting polyethylene]
Low-eluting polyethylene 1: Ultozex 1520L manufactured by Prime Polymer Co., Ltd. C6-LLDPE, density 0.916 g / cm ³ , MFR 2.3 g / 10 minutes. The concentration of elution TOC in a 50 μm thick film is 96 ppm.
-Low-eluting polyethylene 2: Ultozex 3520L manufactured by Prime Polymer Co., Ltd. C6-LLDPE, density 0.931 g / cm ³ , MFR 2.1 g / 10 minutes. The concentration of elution TOC in a 50 μm thick film is 42 ppm.
-Low-eluting polyethylene 3: Neozex 3510F manufactured by Prime Polymer Co., Ltd. C4-LLDPE, density 0.933 g / cm ³ , MFR 1.6 g / 10 minutes. The concentration of elution TOC in a 50 μm thick film is 52 ppm.
Low-eluting polyethylene 4: Ube-Maruzen Polyethylene Co., Ltd., Ube-Maruzen 125NF, HAO-LLDPE (copolymer of higher α-olefin with 6 or more carbon atoms such as C6 and C8 and comonomer LLDPE), density 0.924 g / cm ³ , MFR 2.2 g / 10 minutes. The concentration of elution TOC in a 50 μm thick film is 92 ppm.
-Low-eluting polyethylene 5: Kernel KF283 manufactured by Japan Polyethylene Corporation. Olefin plastomer, density 0.921 g / cm ³ , MFR 2.5 g / 10 min. The concentration of elution TOC in a 50 μm thick film is 98 ppm.

[General-purpose polyethylene]
-General-purpose polyethylene 1: Novatec LC600A manufactured by Japan Polyethylene Corporation. LDPE. Density is 0.918 g / cm ³ , MFR 7 g / 10 minutes.
-General-purpose polyethylene 2: Evolu SP2020 manufactured by Prime Polymer Co., Ltd. C6-LLDPE, density 0.916 g / cm ³ , MFR 2.1 g / 10 minutes. The concentration of elution TOC in a 50 μm thick film is 263 ppm.

[Gas adsorbent]
-Hydrophobic Zeolite 1: Mizusawa Industrial Chemicals Co., Ltd. Hydrophobic Zeolite, Mizuka Sieves EX-122. SiO ₂ / Al ₂ O ₃ molar ratio = 32/1, average particle size = 2.5 to 5.5 μm.
-Hydrophobic Zeolite 2: Hydrophobic Zeolite manufactured by Mizusawa Industrial Chemicals Co., Ltd., Silton MT400
.. SiO ₂ / Al ₂ O ₃ molar ratio = 400/1, average particle size = 5-7 μm.
-Hydrophobic zeolite 3: Hydrophobic zeolite manufactured by Mizusawa Industrial Chemicals Co., Ltd., Silton MT-8000. SiO ₂ / Al ₂ O ₃ molar ratio = 8000/1, average particle size = 0.8 μm.
-Chemisorbent-supported inorganic porous body 1: Kesmon NS-241 manufactured by Toagosei Co., Ltd. Amino group-containing compound-supported inorganic porous body. Average particle size 3.5 μm.
-Chemisorbent-supported inorganic porous body 2: Kesmon NS-80E manufactured by Toagosei Co., Ltd. Hydroxy group-containing compound-supported inorganic porous body. Average particle size 2 μm.

[Flexibility imparting resin]
-Flexibility-imparting resin 1: Toughmer A-4085S manufactured by Mitsui Chemicals, Inc. Ethylene / 1-butene random copolymer, density 0.885 g / cm ³ , MFR 3.6 g / 10 min, Vicat softening point 55 ° C.
-Flexibility-imparting resin 2: INFUSE9100 manufactured by Dow Chemical Co., Ltd. Ethylene / octene block copolymer, density 0.877 g / cm ³ , MFR 1 g / 10 min, Vicat softening point 114 ° C.
-Flexibility-imparting resin 3: Kernel KS340T manufactured by Japan Polyethylene Corporation. Olefin plastomer (metallocene plastomer), density 0.880 g / cm ³ , MFR 3.5 g / cm ³ , Vicat softening point 44 ° C.

[Anti-blocking agent]
-Anti-blocking agent masterbatch 1: PEX-ABT-16 manufactured by Tokyo Ink Co., Ltd. Masterbatch with synthetic zeolite and talc added. Contains 45% by mass of synthetic zeolite, 5% by mass of talc, and 50% by mass of low-density polyethylene.

[Slip agent]
-Slip agent masterbatch 1: EMB-10 manufactured by Sumitomo Mitsui Polyolefin Co., Ltd. Masterbatch of slip agent. Contains 4% by mass of erucic acid amide and 96% by mass of LDPE.

[glue]
-Adhesive 1: Admer NF557 manufactured by Mitsui Chemicals, Inc. Polyolefin adhesive.
[Resin for intermediate layer]
-Nylon resin 1: UBE5033B manufactured by Ube Industries, Ltd. Polyamide 6/66 copolymer.
-Nylon resin 2: UBE6434 manufactured by Ube Industries, Ltd. Polyamide 6/66/12 copolymer.

[Adjustment of masterbatch]
The masterbatch used for the gas adsorption sealant layer was prepared by adjusting as follows.
(Adjustment of masterbatch 1)
General-purpose polyethylene 1 and hydrophobic zeolite 1 were melt-blended at the following ratios to obtain Masterbatch 1 (MB1).
General-purpose polyethylene 1 90 parts by mass Hydrophobic zeolite 1 10 parts by mass

[Adjustment of master batches 2-9]
According to the formulation shown in Table 1, Masterbatch 2-9 (MB2-9) was obtained by melt blending in the same manner as in Masterbatch 1.

[Adjustment of easy piercing sealant layer resin composition]
Easy piercing sealant layer resin compositions 1 to 8 were obtained by dry blending each raw material with the formulations shown in Table 2.

[Preparation of gas adsorption sealant layer resin composition]
Gas adsorption sealant layer resin compositions 1 to 18 were obtained by dry blending each raw material with the formulations shown in Tables 3 and 4.

<Example 1>
Using the easily piercing sealant layer resin composition 1 obtained above, the nylon resin 1, the adhesive 1, and the gas adsorption sealant layer resin composition 1, a laminate having the following layer structure is obtained by an inflation method. rice field.
Then, various evaluations were carried out using the obtained laminate as a packaging material.
(Laminate layer structure)
Easy-to-pierce sealant layer resin composition 1 (30 μm) / adhesive 1 (5 μm) / nylon resin 1 (20 μm) / adhesive 1 (5 μm) / gas adsorption sealant layer resin composition 1 (55 μm) (115 μm in total)

<Examples 2 to 23, Comparative Examples 1 to 4>
Using the raw materials shown in Tables 5 to 8, the same operation as in Example 1 was carried out to obtain a laminate, which was evaluated in the same manner.
The characteristics and evaluation results of the laminated body are shown in Tables 9 to 14.

<Evaluation method>
[Film formation]
The appearance of the laminate was observed and sensually evaluated. The evaluation criteria are as follows.
◯: Film formation is possible without wrinkles or bumps on the laminate.
X: Many wrinkles and bumps occur on the laminated body, making it difficult to form a film.

[Heat sealability]
The laminate was cut into 5 cm x 10 cm, and two sheets were stacked so that the gas adsorption sealant layers faced each other, and two sheets were easily pierced and stacked so that the gas adsorption sealant layer and the gas adsorption sealant layer faced each other. Was prepared, and each was heat-sealed in a 1 cm × 10 cm area using a heat-seal tester (manufactured by Tester Sangyo Co., Ltd .: TP-701-A). State divided into).
Then, each of them was cut into strips with a width of 15 mm, and each of the bifurcated ends was mounted on a tensile tester to measure the tensile strength (N / 15 mm) to determine pass / fail.
Heat seal condition Temperature: 160 ℃
Pressure: 1 kgf / cm ²
Time: 1 second Tensile strength test conditions Test speed: 300 mm / min Load range: 50 N
Pass / Fail Result ○: 30N / 15mm or more, passed.
X: Less than 30 N / 15 mm and failed.

[Standing friction coefficient of easy piercing sealant layer]
As shown in FIG. 6, the SUS jig (sliding piece: weighted 200 g) shown in FIG. 5 is placed on the surface of the cut laminate on the odor adsorption sealant layer side, and the end of the laminate is turned up. The laminate was folded and fixed with double-sided tape on the upper part of the jig. The evaluation was carried out in a normal temperature and humidity environment (23 ° C., 50% RH).
Then, as shown in FIG. 7, the jig to which the laminated body was attached was pulled at a constant speed (100 mm / min), the frictional force between the film surface and the metal plate was measured, and the static friction coefficient was detected.
The measurement was performed 5 times individually, and the average value was calculated.
The detailed conditions are as follows.
Equipment used: Toyo Seiki Friction Tester TR-2

[Pinhole resistance]
The laminate was cut into A4 size (30 cm × 21 cm), bent with a Gelboflex tester (BE-1005 manufactured by Tester Sangyo Co., Ltd.), and then the number of pinholes generated in the laminate was counted.
Temperature: 23 ° C
Gerbo flexion count: 5000 times

[Puncture strength]
A strip-shaped test piece having a size of 120 mm × 80 mm was prepared from the laminated body, and the piercing strength was measured by a method according to JIS Z 1707 1997. 7.5N or less was accepted.

[Filling machine suitability]
The winding raw fabric of the laminated body was passed through a filling machine (Orihiro Co., Ltd., ONPACK-7916 system) to evaluate the bag-making processing state. The evaluation criteria are as follows.
◯: The slipperiness of the film is good, the heat seal part does not shift, and bag making is possible.
X: The film is not slippery enough and the heat seal part is displaced, making bag making difficult.

[Drop resistance]
A pouch (350 mm × 240 mm) was prepared using the laminated body. Then, after filling with 4.7 L of water and repeating vertical dropping from a height of 1 m 5 times, it was confirmed whether or not there was liquid leakage due to bag rupture.
◯: No liquid leakage due to bag breakage.
X: There is a liquid leak due to a broken bag.

[Gas adsorption effect]
(TOC increase concentration of filled water)
A pouch (15 cm × 44 cm) was prepared using the laminated body. The inner surface of the pouch was previously subjected to UV irradiation sterilization treatment.
Then, the pouch was filled with 1000 g of water at 65 ° C. (distilled water for high performance liquid chromatography manufactured by Genuine Chemical Co., Ltd.) to prepare a packaged liquid filler, and after storage at 35 ° C. for 2 weeks, Shimadzu Co., Ltd. The TOC concentration of the filled water was measured by a TOC-L total organic carbon meter manufactured by Mfg. Co., Ltd.
Next, the TOC concentration of the water before filling was measured in the same manner, and the TOC increase concentration in each package was calculated from the following formula.
TOC increase concentration = TOC concentration of filled water after storage-TOC concentration of water before filling TOC concentration of water before filling: 0.02 ppm
UV irradiation sterilization treatment conditions UV wavelength: 253.7 nm
Irradiation time: 10 seconds
Temperature: 25 ° C

(Change in taste of filled water)
A pouch (13 cm × 17 cm) was prepared using the laminated body. The inner surface of the pouch was sterilized and sterilized by UV irradiation in advance. The UV irradiation sterilization treatment was carried out under the same conditions as the TOC increased concentration.
Then, 100 g of water at 65 ° C. (manufactured by Suntory Co., Ltd., natural water from Japan) was hot-packed in the obtained pouch to prepare a liquid packing material for packaging, and the sensory evaluation was performed after storage at 10 ° C. for 1 week. Was carried out.
The index of sensory evaluation is as follows. There were 5 participants in the sensory evaluation experiment, and the average value was calculated and used as the evaluation result.
1: Strong odor 2: Slightly reduced odor 3: Significantly reduced odor 4: Equivalent to natural water before filling

<Summary of results>
The laminates of all the examples, which are the laminates for packaging liquid contents of the present invention, have good film forming property, filling machine suitability, drop body resistance, heat sealability, easy needle piercing property, elastic modulus, and pin resistance. The hole property, the static friction coefficient of the easily pierced sealant layer, and the gas adsorption effect (TOC concentration of the filling water, change in the odor of the filling water) also showed a balance.
However, the laminates of Comparative Examples 1, 2 and 3 in which the gas adsorption sealant layer did not contain low-eluting polyethylene showed a large TOC elution concentration, a poor odor change, and an inferior gas adsorption effect.
Further, in Comparative Example 4 in which the content of the low-eluting polyethylene in the gas adsorption sealant layer was too low and the content of the gas adsorbent was too large, the gas adsorption effect was good, but the film-forming property was inferior.
Further, all the comparative examples in which the easy-piercing sealant layer did not contain the easy-piercing polyethylene showed higher piercing strength than all the examples, and the easy-needle piercing property was inferior.

1 Laminate for liquid content packaging 2 Easy piercing sealant layer 3 Intermediate layer 4 Gas adsorption sealant layer 5 Adhesive layer 10 Chemical adsorbent-bearing inorganic porous body 12 Laminate for liquid content packaging (easy piercing sealant layer) Is outside)
13 Weight 14 Metal plate (mirror brass plate)
15 Heater 16 Pulley 17 Force gauge 18 Vertical electric measuring stand

Claims (20)

A laminate for packaging liquid contents, which has an easily piercing sealant layer on one surface and a gas adsorption sealant layer on the other surface.
The easy-to-pierce sealant layer contains easy-to-penetrate polyethylene and a flexibility-imparting resin.
The gas adsorption sealant layer contains low-eluting polyethylene, the flexibility-imparting resin, and a gas adsorbent.
The concentration of elution TOC contained in the low-eluting polyethylene is 1.5 ppm or more and 250 ppm or less.
The layer thickness ratio of the easy-to-pierce sealant layer / gas adsorption sealant layer is 0.3 to 0.8.
The gas adsorbent contains a hydrophobic zeolite,
The laminate for packaging the liquid contents. The laminate for packaging liquid contents according to claim 1, wherein the gas adsorbent further contains an inorganic porous body carrying a chemical adsorbent. The easy-piercing sealant layer is a layer for imparting easy-needle piercing property to the laminated body, and is used so that the needle first comes into contact with the outside air when the needle is pierced, and has a thickness of 20 μm or more. , 40 μm or less,
The gas adsorption sealant layer is a layer for imparting gas adsorptivity to the laminate, which is used in contact with the liquid content, and contains gas components and / or the laminate. By sterilization treatment using one or more selected from the group consisting of ultraviolet irradiation, heating (hot pack), and boiling, the gas component consisting of the resin decomposition product generated from the laminate for packaging the liquid contents is adsorbed. The layer is 40 μm or more and 70 μm or less in thickness.
The laminate for packaging liquid contents according to claim 1 or 2. The laminate for packaging liquid contents according to any one of claims 1 to 3, wherein the easily piercing polyethylene is C4-LLDPE. The flexibility-imparting resin is an olefin-based thermoplastic elastomer and / or an olefin-based plastomer.
Of the softening resins, density, 0.85 g / cm ³ or more and 0.905 g / cm ³ or less, the Vicat softening point, 35 ° C. or more and 120 ° C. or less,
The laminate for packaging liquid contents according to any one of claims 1 to 4. The liquid content packaging according to any one of claims 1 to 5, wherein the content of the flexibility-imparting resin in the easily piercing sealant layer is 3% by mass or more and 25% by mass or less. Laminated body. The laminate for packaging liquid contents according to any one of claims 1 to 6, wherein the low-eluting polyethylene ^{is LLDPE having a density of 0.90 g / cm 3} or more and 0.94 g / cm ^{3 or less.} body. The liquid content according to any one of claims 1 to 7, wherein the low-eluting polyethylene is one or more selected from the group consisting of C4-LLDPE, C6-LLDPE, and C8-LLDPE. Laminate for packaging. The laminate for packaging liquid contents according to any one of claims 1 to 8, wherein the content of the flexibility-imparting resin in the gas adsorption sealant layer is 2% by mass or more and 25% by mass or less. body. Any one of claims 1 to 9, wherein the gas adsorbent is melt-kneaded in advance in a mass ratio of the thermoplastic resin and the gas adsorbent / thermoplastic resin at a ratio of 5/95 to 40/60. Described in the section,
Laminate for packaging liquid contents. The chemical adsorbent carried by the chemical adsorbent-supporting inorganic porous body has a functional group having reactivity with one or more selected from the group consisting of aldehydes, ketones, and carboxylic acids. The laminate for packaging liquid contents according to any one of claims 2 to 10. The laminate for packaging liquid contents according to any one of claims 2 to 11, wherein the chemical adsorbent supported by the chemical adsorbent-supported inorganic porous body has an amino group or a hydroxyl group. .. An intermediate layer is further included between the easily piercing sealant layer and the gas adsorption sealant layer.
The intermediate layer contains a polyamide resin.
The laminate for packaging liquid contents according to any one of claims 1 to 12. The laminate for packaging liquid contents according to any one of claims 1 to 13, wherein the static friction coefficient of the easily piercing sealant layer is 0.04 or more and 0.3 or less. A packaging material for liquid contents, which is produced by using the laminate for packaging liquid contents according to any one of claims 1 to 14. A packaging material for a water server, which is produced from the laminate for packaging the liquid contents according to any one of claims 1 to 14. A bag-in-box packaging material produced from the laminate for packaging liquid contents according to any one of claims 1 to 14. A liquid content package made from the liquid content packaging material according to claim 15. A water server package made from the water server packaging material according to claim 16. A bag-in-box package made from the bag-in-box packaging material according to claim 17.

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