JP2563071C - - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moisture-proof paper container that can be made into recycled paper using existing equipment. 2. Description of the Related Art A moisture-proof paper container is prepared by melt-extruding and laminating a polyolefin resin such as a polyethylene resin on paper to obtain a moisture-proof paper container blank plate, and then printing the desired blank on the blank. , And obtained by further box making. [0003] The blank plate for a paper container having moisture resistance and the paper container obtained by producing the blank plate are defibrated and converted into recycled paper by existing paper making equipment. When papermaking is attempted, it cannot be separated into a polyethylene resin layer as a moisture-proof layer and paper. For this,
Broken paper and trimming waste of moisture-proof paper container blanks generated in the factory, as well as moisture-proof paper containers collected after use, cannot be recycled using existing papermaking equipment. In fact, these waste papers, trimming wastes, collected paper containers, and the like are actually incinerated. [0004] The reason why a paper container having a moisture-proof property in which a polyethylene resin layer as a moisture-proof layer and paper cannot be separated cannot be recycled is as follows. That is, a strong film made of polyethylene resin is formed on a paper container provided with a polyethylene resin layer as a moisture-proof layer. Therefore, in a coarse separation device such as a pulper, the polyethylene resin layer forming the moisture-proof layer is relatively easily separated from the fiber as a continuous film of the polyethylene resin. However, the separation of the polyethylene resin film is not complete, and the polyethylene resin film that cannot be separated is pulverized in the refiner process to form a small piece of film. [0006] The small pieces of the polyethylene resin film cause clogging of the filter during the filter treatment after the refiner step, so that it is impossible to make recycled paper. On the other hand, according to the present invention, when used as a raw material pulp for recycled paper, the above-described trouble does not occur, paper can be formed on recycled paper by existing equipment, and a high degree of moisture-proofing is obtained. Provided is a paper container having properties. [0008] The above object is achieved by the moisture-proof paper container of the present invention having the following configuration. That is, according to the present invention, an undercoat layer made of an acrylic hydrophobic resin is applied to the entire surface of one of the front and back surfaces of a paper container base paper, and a microcrystalline wax is coated on the undercoat layer. And / or an overcoat layer of an acrylic hydrophobic resin containing paraffin wax is formed except for a margin portion, and the other side of the front and back of the paper container base paper is An undercoat layer made of an acrylic hydrophobic resin is formed except for a margin portion, and an overcoat layer made of an acrylic hydrophobic resin containing microcrystalline wax and / or paraffin wax is formed on the undercoat layer. It is also made of a moisture-proof paper container made of a paper container blank plate that is also formed excluding only the glue margin. In the moisture-proof paper container of the present invention having the above-described structure, the overcoat layer made of the acrylic hydrophobic resin containing microcrystalline wax and / or paraffin wax is formed of the acrylic hydrophobic resin (solid component). It is desirable to contain 5 to 20% by weight of microcrystalline wax and / or paraffin wax. In the moisture-proof paper container of the present invention having the above-described structure, the undercoat layer made of the acrylic hydrophobic resin is provided on the entire surface of one of the front and back surfaces of the paper container blank plate for forming the paper container. And a portion of the other surface excluding only the glue margin, and an overcoat layer made of an acrylic hydrophobic resin containing microcrystalline wax and / or paraffin wax is made of a layer that is suitable for adhesion by an adhesive. Has no
On both the front and back sides of the paper container blank plate, it is formed on the undercoat layer and at a portion excluding only the glue margin. The paper container blank plate produced in the moisture-proof paper container of the present invention is, for example,
Without performing pre-processing on paper such as white paperboard, during one step of gravure printing,
It can be obtained by forming a moisture-proof layer comprising the undercoat layer and the overcoat layer on both the front and back surfaces of the paper. In order to form a moisture-proof layer in one step of gravure printing, a printing machine capable of simultaneously performing pattern application on the front and back sides, for example, 8-color printing of Remanic 115 type by Bobstamplain (Switzerland) It is preferable to use a machine. Further, the blank plate for a paper container produced in the moisture-proof paper container of the present invention can be obtained by forming a moisture-proof layer on a corrugated cardboard liner in one step of flexographic printing by a flexographic printing machine. can get. Therefore, in the step of obtaining the moisture-proof paper container of the present invention, the extrusion lamination step of the molten resin for forming the moisture-proof layer can be omitted, so that the cost can be reduced. The acrylic hydrophobic resin used in the moisture-proof layer of the moisture-proof paper rooster of the present invention includes, for example, an acrylic ester monomer having 7 or more carbon atoms and the acrylic ester monomer A polymer of an acrylate ester having 3 or more carbon atoms in the alkyl group of the alcohol to be obtained, or a copolymer of the acrylate ester and styrene is used. Hereinafter, a specific configuration of a paper container having moisture resistance according to the present invention will be described with reference to production examples. REFERENCE EXAMPLE 1 Using a Remanic 115-type 8-color printing machine from Bobst Champlain (Switzerland), four-color gravure printing was performed on the surface of a white paperboard having a size of 350 g / m ² per square meter.
In the fifth color, an acrylic hydrophobic resin emulsion (acrylic resin solid component: 40
(% By weight) on the surface of the white paperboard except for the adhesive margin, and the sixth color contains 15 parts by weight of microcrystalline wax with respect to 100 parts by weight of the acrylic hydrophobic resin. An overcoat layer of an acrylic hydrophobic resin emulsion (acrylic resin solid component: 40% by weight) was formed on the undercoat layer except for a margin portion. The undercoat layer and the overcoat layer are formed at a plate depth of 100 μm and a line number of 10, respectively.
This was performed using a gravure roll of 0. Subsequently, an undercoat layer of an acrylic hydrophobic resin emulsion (acrylic resin solid component: 40% by weight) is formed on the back surface of the above-mentioned white paperboard in a portion excluding a glue margin portion in the seventh color. In addition, in the eighth color, 1 to 100 parts by weight of the acrylic hydrophobic resin is used.
An overcoat layer of an acrylic hydrophobic resin emulsion containing 5 parts by weight of microcrystalline wax (acrylic resin solid component: 40% by weight) was formed on the undercoat layer except for the glue margin. The undercoat layer and the overcoat layer were formed using a gravure roll having a plate depth of 100 μm and a line number of 100. The blank paperboard having a moisture-proof layer composed of an undercoat layer and an overcoat layer on each of the front and back layers thus obtained is punched into a blank for a paper container, and then subjected to a normal box-making process for reference. Moisture-proof paper container (90 mm long, 150 mm wide, height 110
mm). Example 1 After performing gravure printing of four colors on the surface of 350 g / m ² white paperboard using a Remanic 115-type eight-color printer of Bobst Champlain (Switzerland),
In the fifth color, an acrylic hydrophobic resin emulsion (acrylic resin solid component: 40
(% By weight) on the entire surface of the white paperboard including the glue margin, and the sixth, seventh, and eighth colors of the sixth, seventh, and eighth colors in Reference Example 1 were used.
The same process as the color tinting process was performed to obtain a white paperboard having a moisture-proof layer composed of an undercoat layer and an overcoat layer on each of the front and back sides. Subsequently, the white paperboard having the moisture-proof layer on the front and back sides is punched into a blank sheet for a paper container, and then subjected to a normal box-making process to produce the moisture-proof paper according to one embodiment of the present invention. A container (90 mm long, 150 mm wide, 110 mm high) was obtained. Example 2 A 4-color gravure printing was performed on the surface of 350 g / m ² white paperboard using a Remanic 115-type 8-color printing machine of Bobst Champlain (Switzerland).
The same process as the fifth and sixth colors in the process of obtaining the white paperboard having the moisture-proof layer on the front and back of Reference Example 1 was performed for the fifth and sixth colors, and the seventh color was applied to the back of the white paperboard. An undercoat layer made of an acrylic hydrophobic resin emulsion (acrylic resin solid component: 40% by weight) was formed on the entire surface including the paste margin, and in the eighth color, the reference example 1 was used.
In the same manner as in the eighth color step, white paperboard having a moisture-proof layer consisting of an undercoat layer and an overcoat layer on each of the front and back sides was obtained. Subsequently, the white paperboard having the moisture-proof layer on the front and back sides is punched into a blank plate for a paper container, and then subjected to a normal box-making process to produce a moisture-proof paper according to one embodiment of the present invention. A container (90 mm long, 150 mm wide, 110 mm high) was obtained. Comparative Example 1 Polyethylene resin (Mitsui Petrochemical Co., Ltd .: Mirason 16) was melt-extruded to 20 g / m ² with an extrusion laminator on the surface of 350 g / m ² white paperboard. By pressing a kraft paper having a basis weight of 70 g / m ² on the melt-extruded surface of the above, a moisture-proof paper having a three-layer structure of “white paperboard / coated layer of polyethylene resin / kraft paper” was obtained. Subsequently, the three-layered moisture-proof paper is punched into a blank for a paper container, and then subjected to a normal box-making process to provide a moisture-proof paper container (90 mm long, 150 mm wide, 150 mm wide) for comparison. Height 110 mm). [Experiment 1] Approximately 100 g of calcium chloride was filled in each of the moisture-proof paper containers of Reference Example 1, Examples 1 and 2, and Comparative Example 1 at 40 ° C. and 90% RH. Was measured for 24 hours in an atmosphere (g / m ² · 24 hrs.). The results are shown in [Table 1]. [Experiment 2] Each of the moisture-proof paper containers of Reference Example 1 and Examples 1 and 2 was disintegrated in water to obtain 1% by weight of disintegrated pulp. Beat to 320 ml, and further flat screen (slit width: 0.15 m /
m) to remove foreign matter and form a paper, thereby obtaining Reference Example 1 and Examples 1 to 3.
Three types of recycled paper were obtained using the moisture-proof paper containers of Example 2 as pulp raw materials. Subsequently, each of the obtained recycled papers was subjected to an accelerated thermal drying test (105 ° C. for 30 minutes), and the presence or absence of seepage due to melting of the resin was observed. The results are also shown in [Table 1]. [Experiment 3] Recycling paper using the moisture-proof paper container of Comparative Example 1 as a pulp raw material was attempted in the same manner as in [Experiment 2] described above. The resin film and the paper were separated, but the entire polyethylene resin film could not be removed. For this reason, during the filter treatment after the refiner treatment, small pieces of the polyethylene resin film were clogged in the filter, making it impossible to produce recycled paper. [Table 1] Operation and Effect of the Invention The moisture-proof paper container of the present invention comprises a base coat for paper container and a base coat and a top coat, both of which form a moisture-proof layer laminated on the front and back surfaces of the base paper. Due to the coating layer, it has excellent moisture-proof performance, and has an excellent effect as a packaging material for foods that do not like to absorb moisture and powdery synthetic detergents. Further, in the moisture-proof paper container of the present invention, the moisture-proof layer laminated on the paper container base paper contains an undercoat layer made of an acrylic hydrophobic resin, and microcrystalline wax and / or paraffin wax. When the paper container having the moisture-proof property is disintegrated and converted into recycled paper by the existing paper making equipment, heating and heating during the production process of the recycled paper are performed. In the drying process, the resin component does not seep out to the surface of the papermaking paper. Therefore, the dryer is not contaminated in the process of making the recycled paper, and it is possible to accurately manufacture the recycled paper, and it is also possible to obtain a recycled paper-making paper in a rolled state. In addition, it has an extremely excellent effect in both prevention of environmental pollution. Furthermore, since the moisture-proof layer of the moisture-proof paper container of the present invention can be formed during the printing process on white paperboard or the like, which is the base paper for a paper container, the moisture-proof layer is not melted on conventional paper. As compared with the step of forming the moisture-proof layer by extrusion lamination of the resin, the step of forming the moisture-proof layer is greatly reduced, and the cost can be reduced.

Claims (1)

Claims: 1. An undercoat layer of an acrylic hydrophobic resin is applied to the entire surface of one of the front and back surfaces of a paper container base paper. Has an overcoat layer formed of an acrylic hydrophobic resin containing microcrystalline wax and / or paraffin wax except for a margin portion, and the top and bottom of the paper container base paper described above. On the other side, an undercoat layer made of an acrylic hydrophobic resin is formed except for a margin portion, and an acrylic hydrophobic resin containing microcrystalline wax and / or paraffin wax is formed on the undercoat layer. A paper container having a moisture-proof property, characterized in that a paper container blank plate in which an overcoat layer made of a conductive resin is also formed except for only a glue margin portion is produced. 2. An acrylic hydrophobic resin-containing overcoat layer containing a microcrystalline wax and / or a paraffin wax comprises an acrylic hydrophobic resin (
The moisture-proof paper container according to claim 1, which contains 5 to 20% by weight of the solid component) of microcrystalline wax and / or paraffin wax.