JP6956558B2 - Method for manufacturing a laminate for hydrogen peroxide solution sterilization packaging - Google Patents

Description

The present invention relates to a laminate for hydrogen peroxide solution sterilization packaging and a method for producing the same.

Conventionally, the contents are sterilized by heat-treating at a high temperature for a short time, and the contents are filled in a sterilized packaging material by immersing it in hydrogen peroxide solution in a sterile environment and sealed. Is being done. Such packaging materials are required not to deteriorate when immersed in hydrogen peroxide. Various proposals have been made to achieve this goal.

Patent Document 1 comprises a polyester resin layer having a thickness of 9 μm or less as an outer layer, a polyamide resin layer as an intermediate layer, and a polyolefin resin layer having a low additive content as an inner layer. Laminated films for sterilization packaging have been proposed. Patent Document 1 discloses that a print layer is formed in a region on the intermediate layer side of the outer layer.

Japanese Unexamined Patent Publication No. 2014-156103

When a large amount of packaging laminate is sterilized by immersing a packaging laminate having a printing layer in the region on the intermediate layer side of the conventional outer layer in hydrogen peroxide solution, bubbles are generated in the hydrogen peroxide solution. However, as a result, sterilization with hydrogen peroxide solution may not be performed well. Specifically, the bubbles generated in the hydrogen peroxide solution may adhere to the packaging laminate during the sterilization process, so that the contents may be filled with the bubbles attached and the components of the bubbles may be transferred to the contents. rice field.

Therefore, it is necessary to provide a laminate for hydrogen peroxide solution sterilization packaging which has a printing layer and does not generate bubbles in the hydrogen peroxide solution when immersed in a hydrogen peroxide solution and subjected to a sterilization treatment. exist.

As a result of diligent studies, the present inventors have found that the above problems can be solved by the following means, and have completed the present invention. That is, the present invention is as follows:
<1> (a) A printing layer is formed on at least a part of the intermediate resin layer, and the intermediate resin layer is wound up.
(B) Unwinding the wound intermediate resin layer, and laminating the first adhesive layer on the side of the intermediate resin layer on which the printing layer is laminated.
(C) A first outer resin layer is laminated on the first adhesive layer, and the first outer resin layer, the first adhesive layer, and the intermediate resin layer are provided in this order. Winding up the laminated body,
(D) The wound laminated body is unwound, and the second adhesive layer is laminated on the side opposite to the side where the printed layer of the intermediate resin layer is laminated, and (e) the second adhesive layer. A second outer resin layer is laminated on the top, and the first outer resin layer, the first adhesive layer, the intermediate resin layer, the second adhesive layer, and the second outer resin layer are laminated. A method for producing a laminate for hydrogen peroxide solution sterilization packaging, which comprises winding the laminate for hydrogen peroxide solution sterilization packaging provided in this order.
<2> The method according to the above item <1>, wherein the print layer is formed by applying a composition for a print layer containing an antiblocking agent.
<3> The method according to the above item <1> or <2>, wherein both sides of the first outer resin layer are previously subjected to a wettability improving treatment.
<4> The method according to any one of the above items <1> to <3>, wherein both sides of the intermediate resin layer are previously subjected to a wettability improving treatment.
<5> The method according to the above <3> or <4>, wherein the wettability improving treatment is a treatment selected from the group consisting of a plasma treatment, a corona treatment, and a frame treatment.
<6> A first outer resin layer, a first adhesive layer, an intermediate resin layer, a second adhesive layer, and a second outer resin layer are provided in this order.
A printing layer is provided at least in a part between the first adhesive layer and the intermediate resin layer.
Laminate for hydrogen peroxide solution sterilization packaging.
<7> One of the first and second outer resin layers is made of polyolefin, and the other of the first and second outer resin layers is made of polyolefin or polyester. , The laminate for hydrogen peroxide solution sterilization packaging according to the above item <6>.
<8> The first outer resin layer is made of biaxially stretched polypropylene, and the second outer resin layer is made of linear low-density polyethylene.
The laminate for hydrogen peroxide solution sterilization packaging according to the above item <7>.
<9> The laminate for hydrogen peroxide solution sterilization packaging according to any one of the above items <6> to <8>, wherein the intermediate resin layer is made of polyamide.

According to the present invention, there is provided a laminate for hydrogen peroxide solution sterilization packaging, which has a printing layer and does not generate bubbles in the hydrogen peroxide solution when immersed in a hydrogen peroxide solution and subjected to a sterilization treatment. can do.

FIG. 1 is a diagram showing each step of the method for producing a laminate for hydrogen peroxide solution sterilization packaging of the present invention. FIG. 2 is a diagram showing a layer structure of the laminate for hydrogen peroxide solution sterilization packaging of the present invention.

<< Manufacturing method of laminate for hydrogen peroxide solution sterilization packaging >>
The method of the present invention for producing a laminate for hydrogen peroxide solution sterilization packaging is
(A) A printing layer is formed on at least a part of the intermediate resin layer, and the intermediate resin layer is wound up.
(B) Unwinding the intermediate resin layer, and laminating the first adhesive layer on the side on which the printing layer of the intermediate resin layer is laminated.
(C) A laminate in which the first outer resin layer is laminated on the first adhesive layer, and the first outer resin layer, the first adhesive layer, and the intermediate resin layer are provided in this order. Winding up
(D) The laminate is unwound and the second adhesive layer is laminated on the side opposite to the side where the print layer of the intermediate resin layer is laminated, and (e) the second outer resin is placed on the second adhesive layer. Hydrogen hydrogen water sterilization packaging in which layers are laminated and a first outer resin layer, a first adhesive layer, an intermediate resin layer, a second adhesive layer, and a second outer resin layer are provided in this order. This is a method for producing a laminate for hydrogen peroxide solution sterilization packaging, which comprises winding up the laminate for sterilization.

Regarding the present invention, one of the two adhesive layers in contact with the print layer is referred to as a "first adhesive layer", and the other adhesive layer is referred to as a "second adhesive layer". Mentioned. Further, the outer resin layer in contact with the first adhesive layer of the two outer resin layers is referred to as the "first outer resin layer", and the other outer resin layer is referred to as the "second outer layer". "Resin layer" is mentioned.

When the contents are packaged using the hydrogen peroxide solution sterilization packaging laminate, one of the two outer resin layers can function as a layer exposed to the outside, and the other functions as a layer on the contents side. can do. In particular, the print layer is arranged on the side exposed to the outside of the package as much as possible, and as a result, the first outer resin layer is exposed to the outside from the viewpoint of ensuring the sharpness of the print layer, the influence on the taste, and the like. It is preferable to use a side layer and a second outer resin layer as a content-side layer.

As referred to below with respect to the above steps (b)-(d), according to the method of the present invention, firstly, according to the steps (b) and (c), the printed layer is made into the first adhesive layer and the first adhesive layer. Since it can be coated with one outer resin layer, it is possible to prevent the printing layer from coming into direct contact with the other portion due to subsequent winding. Further, in the step (d), the portion in contact with the print layer when the intermediate resin layer having the print layer is wound is also covered with the second adhesive layer, so that the portion in contact with the print layer is excessive. It is possible to prevent exposure to the surface of the laminated body for hydrogen peroxide water sterilization packaging. As a result, contamination of the laminate for hydrogen peroxide solution sterilization packaging caused by the components of the composition for the printing layer constituting the printing layer is suppressed.

On the other hand, as taught in Patent Document 1, when a print layer is formed in the region on the intermediate layer side of the outer layer and the outer layer in which the print layers are laminated is wound up, the components of the print layer become the outer layer. The components of this print layer are exposed on the surface of the finally produced laminate for sterilization and packaging of hydrogen peroxide, which adheres to the opposite surface, thereby turning the laminate into a solution of hydrogen peroxide. The present inventors have found that this component accumulates in the hydrogen peroxide solution and causes foaming when immersed and sterilized.

Hereinafter, each step of the method of the present invention and the material used in each step will be described with reference to the drawings.

<(A) Formation of print layer>
As shown in FIG. 1A, the print layer is formed by forming the print layer (16) on at least a part of the intermediate resin layer (30) and winding the intermediate resin layer (30). be able to. Winding can be performed using, for example, a winding core (32).

The print layer can be formed by applying the composition for the print layer by printing means such as gravure printing, offset printing, flexographic printing, and silk printing.

{Intermediate resin layer}
As the intermediate resin layer, for example, polyolefin, vinyl-based polymer, polyester, ionomer, polycarbonate, polyamide and the like can be used, but using polyamide can be used for pinhole resistance and tension of the laminate for hydrogen peroxide solution sterilization and packaging. It is preferable from the viewpoint of ensuring physical strength such as strength.

Examples of the polyolefin include polyethylene-based resin and polypropylene-based resin.

In the present specification, the polyethylene-based resin contains a repeating unit of an ethylene group in the main chain of the polymer in an amount of 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, or 80 mol% or more. Resins, such as low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), ethylene-acrylic acid copolymer (EAA), ethylene- Methacrylic acid copolymer (EMAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate copolymer (EMA), ethylene vinyl acetate copolymer (EVA), carboxylic acid-modified polyethylene, carboxylic acid-modified ethylene It is selected from the group consisting of vinyl acetate copolymers, derivatives thereof, and mixtures thereof.

In the present specification, the polypropylene-based resin is a resin containing 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, or 80 mol% or more of repeating units of propylene groups in the main chain of the polymer. Yes, for example, polypropylene (PP) homopolymers, random polypropylene (random PP), block polypropylene (block PP), chlorinated polypropylene, carboxylic acid-modified polypropylene, derivatives thereof, and mixtures thereof.

Examples of vinyl-based polymers include polyvinyl chloride (PVC) and polystyrene.

Examples of the polyester include polyethylene terephthalate (PET) and polybutylene terephthalate.

Examples of the ionomer include a resin obtained by cross-linking a copolymer of ethylene and methacrylic acid with a metal such as zinc.

Examples of the polycarbonate include a resin obtained by condensation polymerization of bisphenol A and carbonyl chloride.

Examples of the polyamide include nylon such as nylon (registered trademark) 6 and nylon MXD6. As the nylon, either unstretched nylon or stretched nylon may be used, but using stretched nylon ensures physical strength such as pinhole resistance and tensile strength of the laminate for hydrogen peroxide solution sterilization packaging. It is preferable from the viewpoint of

Further, it is preferable that the intermediate resin layer further has a barrier layer on at least one surface from the viewpoint of protecting the contents to be packaged from oxygen in the atmosphere. As the barrier layer, for example, a coating film such as an aluminum vapor deposition film, a silica vapor deposition film, an alumina vapor deposition film, a silica / alumina dual vapor deposition film, a polyvinylidene chloride coating film, a polyvinylidene fluoride coating film, or an organic / inorganic hybrid coating film is used. be able to.

As the intermediate resin layer, it is preferable to use a resin film that has been previously subjected to a wettability improving treatment from the viewpoint of ease of forming the print layer. Further, as the resin film, a film in which both sides have been subjected to a wettability improving treatment in advance is preferable from the viewpoint of easy availability. Here, examples of the wettability improving treatment include plasma treatment, corona treatment, frame treatment, and the like.

The thickness of the intermediate resin layer can be 5 μm or more, 10 μm or more, 20 μm or more, or 30 μm or more, and can be 200 μm or less, 180 μm or less, 160 μm or less, 140 μm or less, 120 μm or less, or 100 μm or less. ..

{Print layer}
The print layer can be formed by using the composition for the print layer. As the composition for the printing layer, any commercially available ink can be used.

It is preferable that the composition for the printing layer forming the printing layer contains an antiblocking agent from the viewpoint of preventing the intermediate resin layer from sticking (blocking) when the intermediate resin layer is wound up. On the other hand, since the blocking inhibitor directly contributes to foaming when the laminate for hydrogen peroxide solution sterilization packaging is immersed in the hydrogen peroxide solution, the composition for the printing layer is a blocking inhibitor. The present invention becomes more beneficial when it contains.

Generally, the blocking inhibitor prevents sticking (blocking) with the other surface on which the printing layer is not formed, for example, when a printing layer is formed on one surface of the resin film and wound in a roll shape. Then, in order to facilitate the rewinding of the resin film, it is an additive of granules or powders to be added to the printing layer.

Examples of the blocking inhibitor include inorganic substances such as silica, talc, mica, clay, kaolin, calcium carbonate, barium carbonate, magnesium carbonate, titanium oxide, silicon oxide, aluminum oxide, calcium sulfate, barium sulfate, calcium phosphate, and magnesium phosphate. Examples thereof include particles, organic resin fine particles such as polyolefin-based resin fine particles, urethane resin fine particles, acrylic resin fine particles, and phenol resin fine particles.

<(B) Lamination of the first adhesive layer>
As shown in FIG. 1B, the first adhesive layer is laminated on the side where the wound intermediate resin layer (30) is unwound and the printed layer (16) on the intermediate resin layer (30) is laminated. This can be done by laminating the first adhesive layer (14).

According to this step, since the print layer (16) can be coated with the first adhesive layer (14), it is possible to prevent the print layer (16) from coming into direct contact with other parts due to the subsequent winding. can. However, at this stage, the intermediate resin layer is in contact with the printing layer (16) when it is wound up, so that the portion (16') to which the components of the printing layer are attached is exposed on the surface on the opposite side of the intermediate resin layer. doing.

{First adhesive layer}
As the first adhesive layer, a polyester resin-based, epoxy resin-based, urethane resin-based, silicone resin-based, vinyl acetate resin-based, acrylic resin-based thermosetting adhesive, and a mixture and derivative thereof can be used. ..

The thickness of the first adhesive layer can be 1 μm or more, 3 μm or more, or 5 μm or more, and can be 20 μm or less, 15 μm or less, or 10 μm or less.

<(C) Lamination of the first outer resin layer>
To laminate the first outer resin layer, as shown in FIG. 1 (c), the first outer resin layer (12) is laminated on the first adhesive layer (14), and the first outer resin is laminated. This can be done by winding the intermediate laminate (40) having the layer (12), the first adhesive layer (14), and the intermediate resin layer (30) in this order. Winding can be performed using, for example, a winding core (42).

At this winding stage, a portion further in contact with the portion (16') to which the component of the print layer (16) is attached is formed, but in this portion, the component in the print layer is hardly present.

{First outer resin layer}
Examples of the resin constituting the first outer resin layer include resins that are not deteriorated by hydrogen peroxide, such as polyolefins, vinyl-based polymers, polyesters, ionomers, and polycarbonates. As these resins, the resins mentioned for the intermediate resin layer can be used.

When the contents are packaged using the polypropylene water sterilization packaging laminate and the first outer resin layer is used as the layer to be exposed to the outside, the thermoplastic resin constituting the first outer resin layer. From the viewpoint of ensuring resistance to hydrogen peroxide, it is preferable to use polyolefin or polyester, and in particular, using biaxially stretched polypropylene is preferable from the viewpoint of ensuring the hand-cutting property of the laminate for hydrogen peroxide solution sterilization packaging. preferable.

When the contents are packaged using the laminate for hydrogen peroxide solution sterilization packaging, when the first outer resin layer is used as the layer to be exposed to the outside, the first outer resin layer is previously wettable. It is preferable to use a resin film that has been subjected to an improvement treatment from the viewpoint of improving the suitability of printing with an inkjet printer or the like after filling the contents. Further, as the resin film, a film in which both sides have been subjected to a wettability improving treatment in advance is preferable from the viewpoint of easy availability. Examples of the wettability improving treatment include plasma treatment, corona treatment, frame treatment and the like.

The thickness of the outer resin layer can be 5 μm or more, 10 μm or more, 20 μm or more, or 30 μm or more, and can be 200 μm or less, 180 μm or less, 160 μm or less, 140 μm or less, 120 μm or less, or 100 μm or less. ..

<(D) Lamination of the second adhesive layer>
In the lamination of the second adhesive layer, as shown in FIG. 1D, the wound intermediate laminate (40) is unwound, and the second adhesive layer is on the side opposite to the side where the print layer of the intermediate resin layer (30) is laminated. This can be done by laminating the two adhesive layers (24).

In addition to the print layer (16), the portion (16') to which the component of the print layer is further adhered is covered by the second adhesive layer (24) by this step, so that the portion to which the component of the print layer is adhered (16') It is possible to prevent 16') from being exposed to the surface of the laminate for hydrogen peroxide solution sterilization packaging. As a result, contamination of the laminate for hydrogen peroxide solution sterilization and packaging caused by the components of the composition for the print layer constituting the print layer (16) is suppressed.

{Second adhesive layer}
As the second adhesive layer, the adhesives mentioned for the first adhesive layer can be used.

<(E) Lamination of the second outer resin layer>
To laminate the second outer resin layer, as shown in FIG. 1 (e), the second outer resin layer (22) is laminated on the second adhesive layer (24), and the first outer resin is laminated. Peroxidation comprising a layer (12), a first adhesive layer (14), an intermediate resin layer (30), a second adhesive layer (24), and a second outer resin layer (22) in this order. This can be done by winding up the hydrogen water sterilization packaging laminate (100). Winding can be performed using, for example, a winding core (102).

{Second outer resin layer}
As the second outer resin layer, the resins mentioned for the first outer resin layer can be used.

When the contents are packaged using the hydrogen peroxide solution sterilization packaging laminate, when the second outer resin layer is used as the content side layer, the thermoplastic resin constituting the second outer resin layer is used. , Polyolefin is preferable from the viewpoint of ensuring hydrogen peroxide resistance, and linear low density polyethylene is particularly preferable from the viewpoint of ensuring heat sealability.

The thickness of the second outer resin layer can be 5 μm or more, 10 μm or more, 20 μm or more, or 30 μm or more, and is 200 μm or less, 180 μm or less, 160 μm or less, 140 μm or less, 120 μm or less, or 100 μm or less. be able to.

<Other processes>
The method of the present invention for producing a laminate for hydrogen peroxide solution sterilization packaging may include other optional steps. Other steps include, for example, aging. Aging may be performed, for example, after winding the laminate for hydrogen peroxide solution sterilization packaging.

<< Laminate for hydrogen peroxide solution sterilization packaging >>
As shown in FIG. 2, the laminate for hydrogen peroxide solution sterilization packaging of the present invention, particularly the laminate for hydrogen peroxide solution sterilization packaging produced by the above method, has a first outer resin layer (12) and a first layer. A first adhesive layer (14), an intermediate resin layer (30), a second adhesive layer (24), and a second outer resin layer (22) are provided in this order, and the first adhesive layer (14) is provided. ) And the intermediate resin layer (30), which has a printing layer (16) at least in a part thereof, is a laminate (100) for sterilization and packaging with a hydrogen peroxide solution.

The present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

<< Preparation of laminate for hydrogen peroxide solution sterilization packaging >>
<Example>
According to the procedure shown in FIG. 1, the laminate for hydrogen peroxide solution sterilization packaging of the example was prepared.

More specifically, first, an oil-based gravure ink (Rio Alpha (registered trademark) S, Toyo Ink Co., Ltd.) was applied to a part of the barrier coat nylon (ONYW, Kojin Film & Chemicals Co., Ltd., 15 μm) as an intermediate resin layer. A print layer was formed by gravure printing, and an intermediate resin layer was wound up.

Next, the intermediate resin layer was unwound, and the two-component curable polyester urethane adhesive (RU-50 / H-4, Rock Paint) as the first adhesive layer was placed on the side where the printing layer on the intermediate resin layer was laminated. Company) was laminated.

Next, biaxially stretched polypropylene (YT42, Toray Film Processing Co., Ltd., 25 μm) as the first outer resin layer is laminated on the first adhesive layer, and the first outer resin layer, the first adhesive layer, And the laminate having the intermediate resin layer in this order was wound up.

Next, the laminate was unwound, and a two-component curable polyester urethane adhesive (RU-50 / H-4, Rock Paint Co., Ltd.) as a second adhesive layer was laminated on the intermediate resin layer.

Next, a linear low-density polyethylene (UB106T, Tamapoli, 40 μm) as a second outer resin layer is laminated on the second adhesive layer, and the first outer resin layer, the first adhesive layer, This is carried out by winding up a laminate for hydrogen peroxide solution sterilization packaging having an intermediate resin layer, a second adhesive layer, and a second outer resin layer in this order, and aging at 40 ° C. for 96 hours. An example laminate for hydrogen peroxide solution sterilization packaging was prepared.

<Comparison example>
A print layer is not formed on the intermediate resin layer, but a print layer is formed on the side in contact with the first adhesive layer of biaxially stretched polypropylene (YT42, Toray Film Processing Co., Ltd., 25 μm) as the first outer resin layer, and then A laminate for hydrogen peroxide solution sterilization packaging of Comparative Example was prepared in the same manner as in Examples except that the wound one was used.

<Reference example>
A laminate for hydrogen peroxide solution sterilization packaging of Reference Example was prepared in the same manner as in Examples except that the printing layer was not formed on the intermediate resin layer.

"evaluation"
The prepared laminate for hydrogen peroxide solution sterilization and packaging was cut into 2 × 10 cm rectangles, and one piece was immersed in 50 ml of 35% hydrogen peroxide solution (Yoneyama Yakuhin Kogyo Co., Ltd.) heated to 60 ° C. for 30 seconds. Next, the soaked sheet was taken out, another cut piece was immersed, and this was repeated a certain number of times.

Hydrogen peroxide solution The hydrogen peroxide solution obtained by repeating the immersion of the sterilization packaging laminate a certain number of times is transferred to a 50 ml female linder, an air tube with an air stone at the tip is inserted, and air is blown at 0.8 L / min with an air pump. It was fed for 1 minute and the presence or absence of bubbles was observed.

The results are shown in Table 1. In Table 1, those in which bubbles were not generated are marked with ◯, and those in which bubbles were generated are marked with x.

From Table 1, the laminate for hydrogen peroxide solution sterilization packaging of the example in which the printing layer is present between the first adhesive layer and the intermediate resin layer is the first outer resin layer and the first adhesive layer. Compared with the laminated body for hydrogen peroxide solution sterilization and packaging in which a printed layer is present between and, the hydrogen peroxide solution when the laminate for hydrogen peroxide solution sterilization and packaging is repeatedly immersed a certain number of times. It can be understood that the contamination of the hydrogen peroxide solution is suppressed because the foaming of the hydrogen peroxide solution is suppressed.

12 First outer resin layer 14 First adhesive layer 16 Printing layer 16'Part where the components of the printing layer are attached 22 Second outer resin layer 24 Second adhesive layer 30 Intermediate resin layer 40 Intermediate laminate 100 Peroxidation Laminate for hydrogen water sterilization packaging

Claims (5)

(A) A printing layer is formed on at least a part of the intermediate resin layer, and the intermediate resin layer is wound up.
(B) Unwinding the wound intermediate resin layer, and laminating the first adhesive layer on the side of the intermediate resin layer on which the printing layer is laminated.
(C) A first outer resin layer is laminated on the first adhesive layer, and the first outer resin layer, the first adhesive layer, and the intermediate resin layer are provided in this order. Winding up the laminated body,
(D) The wound laminated body is unwound, and a second adhesive layer is laminated on the side of the intermediate resin layer opposite to the side on which the printed layer is laminated, and (e) the second adhesive layer. A second outer resin layer is laminated on the top, and the first outer resin layer, the first adhesive layer, the intermediate resin layer, the second adhesive layer, and the second outer resin layer are laminated. A method for producing a laminate for hydrogen peroxide solution sterilization packaging, which comprises winding the laminate for hydrogen peroxide solution sterilization packaging provided in this order. The method according to claim 1, wherein the print layer is formed by applying a composition for a print layer containing an antiblocking agent. The method according to claim 1 or 2, wherein both sides of the first outer resin layer are previously subjected to a wettability improving treatment. The method according to any one of claims 1 to 3, wherein both sides of the intermediate resin layer are previously subjected to a wettability improving treatment. The method according to claim 3 or 4, wherein the wettability improving treatment is a treatment selected from the group consisting of a plasma treatment, a corona treatment, and a frame treatment.

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