JP3932533B2 - Method for producing packaging material for liquid food and packaging material for liquid food - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a packaging material for liquid foods such as milk and juice and a packaging material for liquid foods, which can reduce the environmental burden.
[0002]
[Prior art]
As packaging materials for liquid foods such as milk and juice that can reduce the environmental burden, for example, those described in JP-A-5-57847 are known. The packaging material for liquid food is used for normal packaging that is not stored for a long period of time, and is laminated on both sides via a water-soluble thermoplastic resin layer such as polyvinyl alcohol laminated on both sides of the paperboard substrate layer. A thermoplastic synthetic resin (usually polyethylene) is thinly laminated on the side of the container where the printed characters enter. On the other hand, a liquid-resistant material layer 4 made of a thermoplastic synthetic resin such as polyethylene is laminated on the side in contact with the content liquid that becomes the inner surface of the container.
[0003]
For use in aseptically packed packaging for long-term storage, a thin thermoplastic synthetic resin is applied to the container surface side through a water-soluble thermoplastic resin layer such as polyvinyl alcohol laminated on both sides of the paperboard substrate layer. On the other hand, on the surface of the water-soluble thermoplastic resin layer such as polyvinyl alcohol on the inner surface side of the container, a liquid-resistant material layer made of a thermoplastic synthetic resin is provided at a position in contact with the outermost content liquid. A gas barrier material layer such as a metal foil such as an aluminum foil or a gas barrier synthetic resin film is provided on the side. With this packaging material, the paper layer can be easily recovered.
[0004]
The paperboard base layer or paper layer, which is the base paper of the roof-type container and the brick-shaped container, has an intermediate paper layer made of coniferous pulp for improving the paper layer strength and both outer side paper layers made of hardwood pulp for smoothness. A composite paper layer containing a lot of coniferous fibers, and a composite paper layer made of a so-called virgin pulp having a whiteness of 78 to 82 by a non-chlorine bleaching system or a single paper layer. The paper fiber collected from the used paper container is not reused for the paperboard base layer or paper layer that is the base paper of the packaging material for liquid food.
[0005]
The liquid beverage container collected by the milk pack collection route is collected by the procedure of “open, wash, dry, bundle, and take out”. The paper container (main roof-type container) is mainly used for high-grade toilet paper in paper mills of household paper manufacturers nationwide. However, at present, the collection rate of roof-type containers is only about 30%. This is because there are few powerful uses of the recovered paper container as in the recovery and recycling of PET bottles. Even if collected, it is difficult in terms of quantity to effectively reuse the paper fiber.
[0006]
[Problems to be solved by the invention]
In the manufacturing method of the said liquid food packaging materials, such as milk and juice, and the packaging material for liquid foods, the quantitatively powerful use with respect to the container for liquid drinks collect | recovered by a milk pack collection route is desired.
There is an inconvenience that the contents up to that time are slightly adhered to the recovered paper container and cannot be completely removed, and an unpleasant odor is generated, which needs to be eliminated.
It is desirable to eliminate food hygiene hazards due to incomplete sterilization.
The present invention responds to the above-mentioned need and longing, and newly creates a quantitatively powerful application for the recovered liquid beverage container, prevents off-flavors, and is sterilized and safe for food hygiene. It aims at providing the manufacturing method of the packaging material for foods, and the packaging material for liquid foods.
[0007]
[Means for Solving the Problems]
The method for producing a packaging material for liquid food and the packaging material for liquid food of the present invention that solves this problem are mainly composed of long fibers obtained from wood as recognized by the forest certification system on both outer layers of the composite paper layer. It is composed of virgin pulp and is limited to using only the waste paper of the container for liquid beverages collected by the collection route of the milk carton. Recycled material is used only for the intermediate paper layer, and a sterilization system is introduced during paper making. Features.
That is, a paper layer comprising an intermediate paper layer made of long fiber pulp regenerated from waste paper, and an inner and outer paper layer mainly made of virgin pulp laminated on both sides of the intermediate paper layer, and A method for producing a packaging material for liquid food having a thermoplastic resin layer laminated on the outside of a paper layer, wherein the long fiber pulp used in the intermediate layer is collected by a milk pack collection route. Prepared from bleached colored long fiber pulp regenerated only from waste paper, and at least prior to or during the paper making process in the preparation of the paper layer, at least the regenerated pulp is sterilized with ultraviolet rays and reactive oxygen species or with an electron beam using a photocatalyst It is comprised so that it may do.
As a result, the collected liquid beverage container can be reused for a new quantitatively powerful application, and there can be obtained a liquid food packaging material and a method for producing the same that are free from off-flavors and safe in food hygiene.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The method for producing a packaging material for liquid food according to claim 1 of the present invention mainly comprises an intermediate paper layer made of long fiber pulp regenerated from waste paper and long fibers laminated on both sides of the intermediate paper layer. A method for producing a packaging material for liquid food, comprising: a paper layer comprising an inner and outer paper layer made of virgin pulp; and a thermoplastic resin layer laminated on the outer side of the paper layer, Long fiber pulp is prepared from bleached colored long fiber pulp regenerated only from the waste paper of the container for liquid beverages collected by the milk pack collection route, and at least before the paper making process in the preparation of the paper layer, at least during the process This includes sterilizing pulp with ultraviolet rays and reactive oxygen species or with an electron beam utilizing a photocatalyst .
[0009]
Oite this inventions, the sterilization of recycled pulp, in leverage photocatalytic UV and reactive oxygen species, or you sterilized with an electron beam.
[0010]
The packaging material for liquid food according to claim 2 comprises an intermediate paper layer made of long fiber pulp regenerated from waste paper, and a virgin pulp mainly composed of long fibers laminated on both sides of the intermediate paper layer. A liquid food packaging material having a paper layer comprising an inner and outer paper layer and a thermoplastic resin layer laminated on the outer side of the paper layer, wherein the long fiber pulp used for the intermediate layer is collected in a milk pack. Prepared from bleached long fiber pulp regenerated only from waste paper recovered from the container for liquid beverages collected by the route, before or during the paper making process in the preparation of the paper layer, using a photocatalyst, ultraviolet rays and reactive oxygen species Or 35 to 35% by weight of the outer paper layer having surface smoothness that can be directly printed, 20 to 30% by weight of the intermediate paper layer, and 40 to 40% of the inner paper layer. 35% by weight And wherein the Rukoto.
Hereinafter, embodiments of the present invention will be described in detail.
[0011]
In this invention, it is prepared from bleached colored long fiber pulp regenerated only from the waste paper of the container for liquid beverages collected by the milk pack collection route.
Milk packs are collected from the viewpoint of protecting the forest resources by preventing environmental destruction due to the logging of the timber, which is the container material, and collecting the empty packaging containers and forming the laminated material (wrapping web) from these containers. The pulp is reused and the polyethylene contained therein is reused.
According to the rule that environmentally-conscious citizens “open, wash, dry, bundle, and take out”, the collection container for liquid beverage is managed strictly. The recycling process of used empty packaging containers is to clean the collected empty pack containers again, and then shred them regardless of the shape, and shred and separate the pulp component called repulper and other components. Polyethylene containing the pulp content of the paper base material layer and the polyethylene content, or the pulp content of the paper base material layer and other aluminum foil, etc. Separate the minutes. At this time, the shredded packaging laminate material is stirred in the warm water of the repulper tank, and the paper fibers of the paper base material layer are loosened. In separating the polyethylene, a filter device called a screen connected to the repulper or a filter provided in the repulper is used to pass only the fibers that have been loosened and made fine. . Long fiber pulp regenerated only from waste paper in a liquid beverage container is obtained.
The inner and outer paper layers of the present invention are made of virgin pulp mainly composed of long fibers. Virgin pulp is a long fiber made from forest materials recognized by the forest certification system in each country, and is obtained by importing or domestically producing white dioxin-free pulp. Even short fibers can be virgin pulp obtained from wood approved by the forest certification system.
[0012]
This invention includes sterilizing at least the recycled pulp before or during the paper making process in the preparation of the paper layer . The sterilization of playback pulp, by utilizing a photocatalyst can be sterilized by ultraviolet and reactive oxygen species, or may be the sterilization of recycled pulp, sterilized by electron beam.
Although a residue is slightly adhered to the recovered paper container, it is washed in the pulper, so that a bad smell as a pulp does not become a problem. Moreover, the liquid beverage collection container is managed very strictly according to the rules for reducing the environmental load. In the papermaking process in the recycled papermaking process, problems such as odors are prevented by using odor sensors, various monitoring systems, and inspection frequency.
Before or during the papermaking process in the preparation of paper layers, a sterilization and activation device that uses photocatalysts and sterilizes with ultraviolet rays and active oxygen species (OH radicals) will be introduced. Moreover, it can also sterilize using an electron beam. Sterilize all bacteria with an electron beam.
If necessary, a clay coat treatment (CLC) can be applied to the container outer paper layer surface. Surface smoothness and whiteness can be ensured.
If necessary, both the intermediate paper layer and the outer paper layer can be subjected to a minimum sizing treatment of liquid paper such as cross-section water absorption. Demonstrates effects such as cross-section water absorption.
[0013]
The composite paper layer prepared in this invention is used in a paper packaging container called a pack container as a container for selling liquid foods such as milk and juice. As a laminated material (packaging web) mainly composed of the paper layer of the present invention used in such a packaging container, in the case of normal packaging which is not stored for a long time (for example, a gable top seal paper having a gable-shaped top) For example, a polyethylene layer, which is a thin thermoplastic synthetic resin, is directly on the container surface side (the side where printing characters enter) of the paper layer, which is the support layer, and the other side, which is the inner surface of the container. As the liquid-resistant material layer, a laminated material in which a polyethylene layer having a predetermined thickness is laminated (laminated) in one or two layers is used. In the case of aseptically filled packaging containers (generally rectangular parallelepiped containers) for long-term storage, a thin polyethylene layer is directly on the container surface side of the paper layer as the support layer, and the other side that becomes the container inner surface. Is provided with a barrier layer such as an aluminum foil or an inorganic oxide PET film via an adhesive resin layer (generally polyethylene), and a polyethylene layer is laminated on one or two layers as a liquid-resistant material layer on the surface. (Laminated) laminated material is used. Such packaging laminate material (packaging web) is supplied to the packaging filling machine in the form of long rolls with the required printing and crease lines, and is folded in the packaging filling machine to make liquid food as a container. Fill.
[0014]
As shown in FIG. 1, a packaging material 1 for liquid food according to the present invention includes a virgin mainly composed of an intermediate paper layer 2 made of long fiber pulp regenerated from waste paper and long fibers laminated on both sides of the intermediate paper layer. A packaging material for liquid food having at least a paper layer comprising an outer paper layer 3 and an inner paper layer 4 made of pulp, and a thermoplastic resin layer 5 laminated on the outer side of the paper layer. If necessary, the long fiber pulp used in the intermediate layer in which the barrier layer 6 and the plurality of thermoplastic resin layers 5 can be provided is regenerated only from the waste paper of the container for liquid beverages collected by the milk pack collection route. 40 to 35 of the outer paper layer having a surface smoothness which is prepared from the bleached long-colored fiber pulp and sterilized before or during the paper making process in the preparation of the paper layer and which is directly reproducible. % By weight, the intermediate paper layer having 20-30% by weight and the inner paper layer having 40-35% by weight.
In the construction of the paper, it is possible to obtain a fiber density that places importance on rigidity as a paper container. Along with the clay coating treatment, in order to improve the printability on the outermost surface or the printing surface, it is possible to obtain a surface smoothness with appropriate mixing of short fibers and direct printing in view.
[0015]
【The invention's effect】
As described above, according to the present invention, a quantitatively powerful application for a recovered liquid beverage container is newly created, a method for producing a packaging material for liquid food that is safe for food hygiene by preventing odor and sterilizing. And the advantageous effect that the packaging material for liquid foods can be provided is acquired. .
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a liquid food packaging material according to an embodiment of the present invention.
DESCRIPTION OF SYMBOLS 1 ... Packaging material 2 ... Intermediate paper layer 3 ... Outer paper layer 4 ... Inner paper layer 5 ... Thermoplastic resin layer layer 6 ... Barrier layer

Claims (2)

A paper layer comprising an intermediate paper layer made of long fiber pulp regenerated from waste paper, and an inner and outer paper layer made of virgin pulp mainly composed of long fibers laminated on both sides of the intermediate paper layer, and the paper layer A method for producing a packaging material for liquid food having a thermoplastic resin layer laminated on the outside thereof,
The long fiber pulp used for the intermediate layer is prepared from bleached colored long fiber pulp regenerated only from the waste paper of the container for liquid beverages collected by the milk pack collection route,
A method for producing a packaging material for liquid food, which comprises sterilizing at least the recycled pulp with ultraviolet rays and active oxygen species or with an electron beam before or during the paper making process in the preparation of the paper layer. A paper layer comprising an intermediate paper layer made of long fiber pulp regenerated from waste paper, and an inner and outer paper layer made of virgin pulp mainly composed of long fibers laminated on both sides of the intermediate paper layer, and the paper layer A packaging material for liquid food having a thermoplastic resin layer laminated on the outside thereof,
The long fiber pulp used for the intermediate layer is prepared from bleached colored long fiber pulp regenerated only from the waste paper of the container for liquid beverages collected by the milk pack collection route,
The recycled pulp sterilized with ultraviolet rays and active oxygen species or with an electron beam using a photocatalyst before or during the paper making process in the preparation of the paper layer,
Package for liquid food, characterized in that the outer paper layer having surface smoothness which can be directly printed has 40 to 35% by weight, the intermediate paper layer has 20 to 30% by weight and the inner paper layer has 40 to 35% by weight. material.

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