JP2015077780A - Paper member nd paper container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper member having less effect by humidity and moisture and gas barrier property such as oxygen gas without using a molten resin between paper and a barrier coating layer nor coating an adhesive agent.SOLUTION: There is provided a paper member (1) having a barrier coating layer (3) and a sealant layer (4) on a paper surface in a side with which contents contact, and at least one layer of any coating of a barrier urethane resin, a barrier acryl resin, a mixture of flat powder and vinyl alcohol resin, a mixture of flat powder and barrier acryl resin and a mixture containing the barrier urethane resin and the barrier acryl resin is arranged as the barrier coating layer.

Description

  The present invention relates to a paper member used in manufacturing a paper container mainly composed of paper. This paper member relates to a paper member used for a paper container for storing contents that require barrier properties such as oxygen gas and fragrance, for example, food such as juice and liquor, for preservation.

As a method for imparting a gas barrier property to paper, there are a method of bonding a synthetic resin film having low gas permeability, or a method of bonding a film subjected to vapor deposition of metal, silicon oxide, or the like.
For example, a laminate of films of ethylene-vinyl alcohol copolymer, polyvinylidene chloride, polyacrylonitrile, polyethylene terephthalate resin, etc. has high gas barrier properties. In addition, metal foil such as aluminum foil, polyethylene terephthalate film deposited with aluminum, and polyethylene terephthalate film deposited with silicon oxide also have high gas barrier properties.
However, such a film or metal foil having a high barrier property cannot be directly bonded to paper. In the case of bonding, a method such as laminating a molten resin between a paper and a film having a high barrier property or a metal foil, or coating with an adhesive, is required.
Because it was necessary to apply the molten resin via an adhesive on the surface where the paper and the film having the barrier property were combined, and also on the surface on the sealant layer side of the film having the barrier property. However, there are many manufacturing processes, and there is a problem that it must be expensive.

Patent Document 1 describes that a paper having gas barrier properties is obtained by applying a polyvinyl alcohol-based resin aqueous solution to a paper substrate, drying it, and holding it at a constant temperature.
This method is a component that polyvinyl alcohol resin can be disposed of together with paper, so it has excellent merit as a material for producing paper containers, such as excellent recyclability and low oxygen permeability. It is a certain paper member.
However, the properties of polyvinyl alcohol are significantly deteriorated due to moisture and humidity, and particularly when the contents contain moisture, it easily swells, peels, dissolves, and cannot maintain its shape. Had occurred.
Moreover, since the paper has a large pulp fiber ratio and a small amount of binder, the paper has high permeability and polyvinyl alcohol easily penetrates deeply into the paper substrate. Therefore, unless measures are taken such as increasing the viscosity or making the coating thickness very large, unevenness is likely to occur due to the density variation of the pulp fibers, and it is difficult to form a good layer without defects. In addition, since it is an aqueous solvent, it takes time to dry, and there is a problem that production can be performed only with special equipment having a very long drying line, and the production speed has to be extremely slow.
Furthermore, when this paper member is formed into a container such as a paper pack or a paper cup, a sealant layer 4 for fusing at least the inner surfaces is provided, resulting in a cross section as shown in FIG.
As described above, the barrier coating layer made of polyvinyl alcohol provided on the inner side of the paper 2 is easy to be uneven due to the density variation of the pulp fiber of the paper, and penetrates to form a penetrating portion, which is good without defects. Layer or surface is difficult to form. However, the paper container requires strength between the sealant layer 4 and the paper 2 both when the container is molded and when it is used. If the barrier coating layer is too thick, the problem that the interlayer is likely to be peeled off easily occurs. There was also.

JP 2001-254292 A

  In view of the above problems, even if the barrier coating layer with high permeability is thin, the layer is formed uniformly and is not coated with an adhesive, and is less affected by humidity and moisture, and is a gas barrier such as oxygen gas. It is an object of the present invention to obtain a highly productive and highly productive paper member at low cost.

  The paper member according to claim 1 of the present invention is a paper member characterized in that a melted polyethylene layer, a barrier coating layer, and a sealant layer are provided on the paper surface on which the contents are in contact.

  The paper member according to claim 2 of the present invention is the paper member according to claim 1, wherein the paper is coated paper, and a barrier coating layer is provided on the coated surface.

  The paper member according to claim 3 of the present invention is the paper member according to claim 1 or 2, wherein a molten polyethylene resin layer is used as the sealant layer.

  The paper member according to claim 4 of the present invention has a barrier urethane resin, a barrier acrylic resin, a mixture of flat powder and vinyl alcohol resin, a mixture of flat powder and barrier acrylic resin, or a barrier coating layer as a barrier coating layer. The paper member according to any one of claims 1 to 3, wherein at least one layer of any coating of a mixture containing a conductive urethane resin and a barrier acrylic resin is provided.

  The paper member according to claim 5 of the present invention is characterized in that the flat powder is an inorganic layered mineral, mica, metamorphic rocks mainly composed of mica, and water-swellable synthetic mica. It is a member.

  In the paper member according to claim 6 of the present invention, the barrier urethane resin includes an aqueous polyurethane resin (A) containing a polyurethane resin having an acid group and a polyamine compound, a water-soluble polymer (B), and a flat powder ( The paper member according to claim 4, wherein the paper member is a mixed resin having C) as a main constituent.

  The paper member according to claim 7 of the present invention is characterized in that the barrier acrylic resin is a mixed resin of an aqueous coating solution containing a poly (meth) acrylic acid polymer, a polyalcohol polymer, and an aqueous medium. It is a paper member in any one of Claims 4-6.

  The paper member according to claim 8 of the present invention is characterized in that the water-soluble polymer (B) is a polyvinyl alcohol resin having a saponification degree of 95% or more and a polymerization degree of 300 to 2000. This is a paper member.

  The paper member according to claim 9 of the present invention is the paper member according to claim 7, wherein the aqueous coating solution contains a plasticizer.

  A paper container according to a tenth aspect of the present invention has a body portion and a bottom portion made of the paper member according to any one of the first to ninth aspects, and the body portion has a winding and fusing portion. It is a container.

  The paper container according to an eleventh aspect of the present invention is the paper container according to the tenth aspect, wherein no barrier coating layer is provided on the edge of the paper member of the winding drum.

  The paper container according to claim 12 of the present invention is characterized in that the width of the region where the barrier coating layer is not provided on the edge of the paper member of the winding drum portion is shorter than the fusion width of the wound and fused. Item 12. A paper container according to Item 11.

  A paper container according to a thirteenth aspect of the present invention is the paper container according to any one of the tenth to twelfth aspects, wherein the edge of the paper member of the winding drum portion is skive-hemmed.

  The paper container according to claim 14 of the present invention is such that the edge of the paper member of the winding drum is previously punched around the winding and fusing portion, and a fusion-bondable thermoplastic resin is bonded to the edge of the paper container. The paper container according to any one of claims 10 to 12, wherein the paper container is covered with a layer.

The paper member of the present invention does not cause deterioration of physical properties or the like due to moisture, as well as moisture-free content. And since the barrier coating layer is formed in a uniform layer, the gas barrier property is high, the contents can be kept in a state that hardly causes oxidative deterioration, and the contents such as food can be stored for a long time. .
In addition, since the manufacturing process is small and the productivity is high, the paper member of the present invention can be manufactured at low cost.

It is sectional drawing which shows the 1st embodiment form of the paper member of this invention. It is the perspective schematic diagram which looked at the cross section which shows the mechanism of the barrier property by flat powder in the first embodiment form of the storage container of the present invention. It is a cross-sectional schematic diagram which shows the 2nd embodiment of the paper member of this invention. It is sectional drawing which shows the detail of the coating surface of the 2nd embodiment form of the paper member of this invention. It is the see-through | perspective schematic diagram which looked at the cross section which shows the mechanism of the barrier property by flat powder in the 2nd embodiment of the storage container of this invention. It is a perspective view which manufactures a paper container from a paper member. It is a figure which shows the condition which removes a winding melt | fusion part from a coating range in the manufacturing process of a paper member. It is an expanded sectional view in the fusion part at the time of manufacturing a paper container. FIG. 3 is an enlarged cross-sectional view of a lap-bonding portion subjected to end face protection treatment in the paper container of the present invention. In the paper container of this invention, it is an expanded sectional view of the fusion | melting part which removed the winding fusion | bonding part from the coating range.

Hereinafter, the paper member of the present invention will be described in detail with reference to the drawings.
A diagram showing a first embodiment of the paper member of the present invention is shown in FIG. This paper member 1 is a paper member in which a barrier coating layer 3 and a sealant layer 4 are provided on a surface b on the side where the contents of the base paper 2 are in contact.
Here, the front surface a is not particularly shown as being coated, but a coating layer may be provided for printing or preventing the contents from bleeding.

  The barrier coating layer 3 comprises a barrier urethane resin, a barrier acrylic resin, a mixture of flat powder and vinyl alcohol resin, a mixture of flat powder and barrier acrylic resin, or a barrier urethane resin and barrier acrylic resin. At least one layer of any of the mixed resin coatings is provided.

Here, the barrier urethane resin means an aqueous polyurethane resin (A) containing a polyurethane resin having an acid group and a polyamine compound, a water-soluble polymer (B), and an inorganic layered mineral (
C) is a mixed resin mainly composed of components.
And in this barrier urethane resin, the blending ratio of the aqueous polyurethane resin (A), the water-soluble polymer (B) and the inorganic layered mineral (C) in the mixed resin is:
Aqueous polyurethane resin (A) 5-80% by mass, preferably 50-80% by mass,
Water-soluble polymer (B) 5 to 80% by mass, preferably 5 to 20% by mass,
Inorganic layered mineral (C) 8-30% by mass, preferably 10-30% by mass
It is preferable that it is the range of these.

The water-soluble polymer (B) is preferably a polyvinyl alcohol resin having a saponification degree of 95% or more and a polymerization degree of 300 to 2000.
The higher the degree of saponification and polymerization, the lower the hygroscopic swelling property of the polyvinyl alcohol resin.
When the saponification degree of the polyvinyl alcohol resin is lower than 95%, it is difficult to obtain a sufficient gas barrier property.
When the polymerization degree of the polyvinyl alcohol resin is lower than 300, the gas barrier property is lowered. On the other hand, when the polymerization degree of the polyvinyl alcohol resin exceeds 2000, the viscosity of the water-based coating agent is increased, and it is difficult to uniformly mix with other components, which causes problems such as deterioration of gas barrier properties and adhesion. Absent.

Further, as the flat powder, an inorganic layered mineral is particularly preferable. Inorganic layered minerals have a cleavage property that allows crystals to peel thinly into layers. High-pressure cis-type single-chain or double-chain SiO ₄ chains are connected indefinitely in the lateral direction, and the SiO ₄ hexagonal ring is a honeycomb. It is a mineral that forms a flat SiO ₄ sheet that is lined up in the shape of a layer. The tetrahedron sheet and the octahedron sheet overlap each other, and the bond at the boundary is connected by van der Waals force.
In muscovite, etc., only exchangeable cations are sandwiched between layers of tetrahedral and octahedral sheets, but water-swelling synthetic mica such as “smectite” sandwiches an additional layer of water. , Water molecules are taken in and out, and the volume changes greatly.
Examples of the inorganic layered mineral used in the present invention include minerals such as muscovite, biotite, and phlogopite, or metamorphic rocks mainly composed of mica, and water-swelling synthetic mica, kaolinite, talc, and chlorite. used.
In these inorganic layered minerals, the planar direction of the layer is a high-density crystal that prevents the transmission of moisture, oxygen gas, fragrance, and the like.
Therefore, in this coating, it is necessary to carry out the coating with the viscosity as low as possible, to dry it while keeping the coating substrate horizontally, and to volatilize the medium system such as water quickly.

The barrier acrylic resin is a mixed resin of an aqueous coating solution containing a poly (meth) acrylic acid polymer, a polyalcohol polymer, and an aqueous medium, an aqueous solution or an aqueous dispersion, a solution, suspension, colloid or Can be used in the latex state.
Here, the polyalcohol-based polymer is a polymer having two or more hydroxyl groups in one molecule. For example, polyvinyl alcohol resin and sugars.
In particular, in the case of polyvinyl alcohol, those having a saponification degree of 95% or more and a polymerization degree in the range of 300 to 2500, preferably 300 to 1500 are particularly preferable because they exhibit gas barrier properties. In this case, as in the case of barrier urethane, if the degree of saponification is 95% or less, the gas barrier property is lowered. On the other hand, when the polymerization degree of the polyvinyl alcohol resin exceeds 2500, the viscosity of the water-based coating agent is increased, and it is difficult to uniformly mix with other components, which may cause problems such as gas barrier properties and lower adhesion. Absent.
In the case of saccharides, monosaccharides, oligosaccharides, polysaccharides, sugar alcohols obtained by using their reducing ends as alcohols, and those obtained by chemically modifying them are exemplified. Among them, malto-oligosaccharides, water-soluble starches, sugar alcohols thereof, sorbitol, dextrin, pullulan and the like have produced good results in combination with poly (meth) acrylic acid polymers.
The poly (meth) acrylic acid polymer is a polymer containing two or more carboxyl groups in one molecule. For example, polyacrylic acid, polymethacrylic acid, a copolymer of polyacrylic acid and polymethacrylic acid, or a mixture thereof can be considered. In particular, a copolymer of acrylic acid and polymethacrylic acid, and a copolymer having more polyacrylic acid monomers than polymethacrylic acid monomers exhibits more preferable gas barrier properties.

The polyalcohol-based polymer is polar, water-soluble, and has a high gas barrier property, but has high moisture absorption and permeation properties such as water.
However, when mixed with a resin of a poly (meth) acrylic acid polymer, the movement of water molecules is controlled and the influence of water molecules is suppressed, so that gas barrier properties such as oxygen and fragrance are improved.
The aqueous medium is water or a water-containing medium. In the case of the water-containing medium, the water-containing medium contains water at 30 percent or more, preferably 50 percent or more, and examples thereof include methanol, ethanol, isopropyl alcohol, and acetone.

The content of the aqueous medium is preferably 0.1 to 99 percent, preferably 5 to 95 percent of the total weight of the poly (meth) acrylic acid polymer and the polyalcohol polymer.
If it is 0.1% or less, there is a problem that cracks are generated on the coating surface, and if it is 99% or more, drying is remarkably lowered and productivity is lost.
The composition ratio of the poly (meth) acrylic acid polymer resin and the polyalcohol polymer is preferably a weight ratio of poly (meth) acrylic acid polymer: polyalcohol polymer = 95: 5 to 10:90. In particular, poly (meth) acrylic acid polymer: polyalcohol polymer = 90: 10 to 40:60 is more preferable.
In addition, by including a plasticizer in the aqueous coating liquid, cracking thereof is prevented, and gas barrier properties are further improved. The plasticizer content is 1 to 50 percent, preferably 1 to 30 percent of the total weight of the poly (meth) acrylic acid polymer and the polyalcohol polymer.
Specific examples of this plasticizer include ethylene glycol, trimethylene glycol, propylene glycol, tetramethylene glycol, 1,3-butanediol, 2,3-butanediol, pentamethylene glycol, hexamethylene glycol, diethylene glycol, triethylene glycol, Ethylene glycol, trimethylolpropane, sorbitol, mannitol, dulcitol, erythritol, glycerin and the like, and these simple substances or a mixture containing a plurality of them can be used as a plasticizer.
The coating thickness in the final product is preferably 0.1 to 100 micrometers, particularly 0.5 to 5 micrometers.

By the way, the base paper 2 is obtained by bonding pulp fibers with a binder. The surface of the paper has fibers that are curled in a flat shape, but overlaps and entangles in a random direction, and the density of the pulp fibers is high in some places, but the density is low in some places. Moreover, the density of the binder is lower than that of pulp fibers. Therefore, even if the paper 2 is thinly coated with the barrier coating layer 3, the unevenness on the paper surface is not eliminated. Therefore, the thin barrier coating layer 3 may be accumulated and thickened, but it is very thin and has a problem that a hole is easily formed.
Therefore, there is a method of providing a thick barrier coating layer 3 that is equal to or greater than the irregularities on the paper surface, but it is preferable to coat the barrier coating a plurality of times to ensure a thickness that can exhibit performance even at the thinnest place. In particular, since it is an aqueous coating, coating is preferably performed in a plurality of times, and in the final coating, the flat powder is oriented and overlaps without gaps.

A sealant layer 4 is provided on the barrier coating layer 3. As the sealant layer 4, a melted high-pressure low-density polyethylene resin, an ethylene vinyl acetate copolymer, a linear low-density polyethylene resin, an ionomer resin, or the like is used and bonded together by a melt extrusion lamination machine. Of course, the sealant film may be bonded with an adhesive.
This sealant layer has a role of fusing the inner surfaces of the container to form a shape, and a contact with the contents, thus preventing the contents from bleeding into the paper side. However, it is a resin that melts at a low temperature and easily adheres firmly, and does not crystallize and is solidified in a random state. Therefore, it has a high permeability to oil and oxygen gas, and also has a high moisture permeability. Has some degree.

FIG. 2 is a perspective view schematically showing a cross-sectional view showing the mechanism of the barrier property by the flat powder in the first embodiment of the present invention.
The base paper 2 easily penetrates because there is a space between the paper fibers. On the content contact surface side of the paper 2, a barrier coating layer 3 including a flat powder 6 is provided. Further, a sealant layer 4 is provided on the content contact surface side.
The flat powder 6 used for the barrier coating layer 3 in this figure is biotite, an inorganic layered mineral, which is repelled by the flat powder 6 and shows oxygen gas 7 that does not permeate. However, although there is oxygen gas 8 that permeates through only the gaps of the flat powder 6, the permeable passage is narrow and is slight.
Since this flat powder 6 is layered and has a certain surface, it is possible to coat so that the surfaces forming the layers overlap each other and cover the barrier coating layer 3 with the flat powder 6, As a whole, a barrier coating layer having a high gas barrier property can be obtained. In this way, a barrier property can be imparted to the highly air-permeable material of paper 2.

FIG. 3 is a sectional view showing another second embodiment of the paper member of the present invention.
This paper member 1 uses a coated paper in which a coating 5 (coating agent) is coated on the surface b of the base paper 2 that contacts the contents, and the barrier coating layer 3, the sealant layer 4, and the coated surface are coated on the coated surface. It is a paper member provided.

The coated paper is also called coated paper, and the paint 5 used for the coated paper is made by mixing a white pigment such as clay (kaolin) or calcium carbonate and an adhesive (binder) such as starch. The paint is applied using a coater during the paper manufacturing process. The coater may be an on-machine type in which paper making and coating are performed in one step by being directly connected to a paper machine, or an off-machine type in which the paper making and coating are performed separately.
Actually, as shown in FIG. 4, the surface of the paper 2 is not smooth, and the density of the forming fibers varies. For this reason, when a barrier coating layer is provided in this state, the flat powder that provides barrier properties cannot be arranged in a certain direction unless the coating is repeated several times on a considerably thick layer. However, by applying the coating material 5, a part of the coating 5 penetrates into the paper 2, filling the recesses, greatly repairing the surface, and creating a coated paper with a smooth surface.
The coated paper by coating the coating material at a basis weight of normally ^{15g / m 2 ~40g / m 2} , or protruding fibers of paper was before coating to the surface, the surface state of the recess has occurred The surface of the paper is smooth and the unevenness on the paper surface is relaxed. Therefore, when this coated paper is used, even if the barrier coating layer is thin, a smooth and uniform barrier coating layer can be easily formed, and thus high barrier properties can be exhibited. In particular, gloss type coated paper is preferred.

The coating layer on the front surface a side can be simply bonded to the paper 2 with a melt extrusion bonding machine. The molten polyethylene resin may be a high pressure low density polyethylene resin, but may be a linear low density polyethylene resin, a medium density polyethylene resin, an ethylene vinyl acetate copolymer, or a mixed resin thereof.
The thickness may be thin or thick, but is 12 to 60 micrometers, preferably 18
Bond with ~ 40 micrometers.

FIG. 5 is a perspective schematic view of the cross section of the paper member of the second embodiment in perspective, and is a diagram showing the mechanism of the barrier property by the flat powder.
Since the base paper 2 has a space between the paper fibers, oxygen gas, odorous substances and the like are easily transmitted therethrough.
The content contact surface b side of the paper 2 is a surface with irregularities, but the coating 5 layer is coated, and the inner surface side to be barrier-coated forms a smooth coat surface c. Oxygen gas, odorous substances, and the like easily pass through the layer of paint 5.
Further, the barrier coating layer 3 including the flat powder 6 is provided on the content contacting surface side of the layer of the paint 5. Further, a sealant layer 4 is provided on the content contact surface side.
The flat powder 6 used in the barrier coating layer 3 in this figure is inorganic layered mineral biotite or the like, and is repelled by the flat powder 6 so that the oxygen gas 7 hardly permeates. In particular, since the coating 5 is applied to a smooth surface, the flat powder 6 can be overlapped so that the same cleaved surfaces overlap along the surface. Then, the flat powder 6 can be covered so that almost no gap is left. Therefore, even if the oxygen gas 8 tries to permeate through only the gaps of the flat powder 6, the permeable passage is narrow and can pass through very little.
Since this flat powder 6 has a certain surface in a layered form, it can be arranged so that the surfaces forming the layers overlap each other and the barrier coating layer is covered with the flat powder 6 as a whole. A barrier coating layer having a high gas barrier property can be obtained.
In this way, a barrier property can be imparted to the highly air-permeable material of paper 2.

By the way, the paper member of the present invention is configured to ensure barrier properties by itself, but when this paper member is used as a paper container as it is, for example, in a cup container, the paper member There is a problem that the end face 21 is exposed.
That is, when the paper cup is manufactured, the winding and fusion part 9 is generated as shown in FIG. In order to produce a paper container, a surface fusion layer 40 is provided on the outer surface side of the paper substrate so that a wound portion can be formed.
However, when the paper member is wound as it is, the end face 21 of the paper member is exposed as shown in FIG.
In such a state where the end face is exposed and the contents are liquid and the end face is immersed, the contents destroy the barrier coating layer 3 because the barrier coating layer 3 uses a water-soluble resin. There is a risk that the front and back will be separated. In particular, since a water-soluble coating resin is used, there is a problem that even the end face permeates and elutes from the end face and the paper container itself is destroyed. Even if the content does not destroy the coating layer, there is a problem that the content permeates from the end face of the highly air-permeable paper and the barrier property cannot be secured.
Therefore, it is necessary to prevent the barrier coating layer and the base paper from being exposed to the inner surface of the container on the end surface of the paper member.

For this purpose, as shown in FIG. 7, the winding and fusion part 9 is coated so as to be out of the coating range of the barrier coating layer 3. If a gravure printing machine is used for coating and the arrangement of the body portion with respect to the paper member is devised, it can be partially removed from the coating range 300 as shown in FIG.
However, if the non-coating range 301 is too large, the barrier layer in the vicinity of the lap-bonding portion 9 is lost, and there is a possibility that transmission of oxygen or the like will increase. Therefore, it is necessary to make the width of the non-coating range 301 smaller than the width of the wound portion 9.
Further, as shown in FIG. 8B, when the end face 21 of the paper member is exposed even if the width 91 of the non-coating range is set to be smaller than the width of the lap-bonding fusion portion 9, There is a problem that the content penetrates from the end face and breaks the barrier coating layer 3.

  On the other hand, as shown in FIG. 9A, by forming a folded portion in the vicinity of the end face that becomes the inside of the container, the end face 21 of the paper member is formed so that the end face 21 of the barrier coating layer 3 does not come out. Can be. When there is no surface fusion layer on the outer side of the paper base material 2, the end face does not come out and the barrier property can be secured by bonding together in this way, but the entire paper member is folded back greatly, so the thickness of the fusion surface However, there is a problem that the fusion strength of the bottom plate is difficult to be obtained.

  Fig. 9-2 shows that the sealant layer 4 is formed by extending the sealant layer 4 over the paper 2 by forming a sealant layer after the paper base material is partially cut out, and forming the sealant layer. It is an example of a method using it. In this method, the sealant end face entraining part 42 is formed by fusing to the sealant layer 4 at the other end to which the sealant layer single unit fusion part 41 is wound while covering the paper end face 21 when forming the lap fusion part 9. This is an end face exposure prevention process.

  Also, in FIG. 9-3, the sealant layer single unit fusion part in which the sealant layer is stretched more than the paper 2 by manufacturing the paper base by pasting out a part of the outer shape of the paper substrate in the same manner. 41 is formed. The sheet end surface 21 is covered with the sealant layer single unit fusion portion 41 to form a sealant end surface winding portion 42. This is an example of an end face exposure prevention process in which the winding and fusing part 9 including the sealant end face winding part 42 is fused to the sealant layer 4 at the other end.

Further, a method in which the edge of the paper member of the winding and fusing part 9 is skived and hemmed may be used. FIG. 9-4 shows the edge of the paper member of the lap-bonding portion 9 where the edge of the paper member is a predetermined width from the tip, and a part of the thickness of the paper member 1 is deleted (skived) from the outside and scraped off. It is sectional drawing of the skive hemming process fusion | melting part 43 incorporating the skive hemming process method which folds back (hemming) the remaining part so that a deletion surface may become inside, and protects a paper end surface. Even in this method, the exposure of the end face can be prevented, and the barrier coating layer 3 can be prevented from being lowered. Thus, when the end face exposure prevention treatment is performed, there is no permeation of the contents, so that the barrier coating layer 4 is not deteriorated. Even after processing into a container, high performance can be maintained. In the case of the present invention, unlike the stiff barrier resin film, since it is made of a coating, there is an advantage that such processing is easy to process.

  Furthermore, when the non-coating fusion part 91 is provided in the winding fusion part 9, the end face processing becomes easy to process. For example, when the barrier coating layer 3 is present in the wound and fused portion 9, there is a problem that peeling is likely to occur inside the barrier coating layer 3 and it is difficult to manufacture a stable container. This can be solved by providing the non-coating fused portion 91 as a countermeasure. In particular, it is desirable that the vicinity of the end face to be entrained is the non-coating fused portion 91.

  In FIG. 10A, a sealant layer unit fusion part 41 in which the sealant layer 4 is extended from the paper 2 is formed by manufacturing the paper base material after removing a part of the outer shape of the paper base material. It is an example of a method using it. When removing a part of the outer shape, if there is a barrier coating layer at the place to cut, the cutting of the blade is likely to deteriorate, and therefore peeling near the cutting is likely to occur. , Improve productivity. In this method, the sealant end face entraining part 42 is formed by fusing to the sealant layer 4 at the other end to which the sealant layer single unit fusion part 41 is wound while covering the paper end face 21 when forming the lap fusion part 9. This is an end face exposure prevention process.

In FIG. 10-2, the sealant layer unit fusion part 41 in which the sealant layer is extended from the paper 2 is manufactured by pasting a part of the outer shape of the paper base material and then bonding the sealant layer. Let it form. Similar to FIG. 10-1, such as the problem of cutting when extracting a part of the outer shape, cutting performance is improved by cutting in the non-coating range, and the sealant layer single unit fusion portion in which the sealant layer 4 is extended from the paper 2. 41 becomes easy to form. The paper end surface 21 is covered with the sealant layer single unit fusion portion 41 to form the sealant end surface winding portion 42. This is an end face exposure prevention treatment for fusing the winding and fusing part 9 including the sealant end face winding part 42 to the sealant layer 4 at the other end.

In FIG. 10-3, at the edge of the paper member of the winding and fusing part 9, the edge of the paper member is deleted from the outside by a predetermined width, and a part of the thickness of the paper member 1 is deleted (skived) from the outside. It is sectional drawing of the skive hemming process fusion | melting part 43 incorporating the skive hemming processing method which folds back (hemming) the remaining part cut off so that a deletion surface may become inside, and protects a paper end surface.
When a part of the thickness of the paper member 1 is removed from the outside (skive), if there is a barrier coating layer 3 that is easy to peel off inside the layer, the shaving blade to be removed is slippery and it is difficult to form a good cross section was there. However, this can be solved by setting a part of the thickness of the paper member 1 as a non-coating range in a range in which the outer part is deleted (skived) from the outside. Even in this method, it is possible to prevent the end face from being exposed and prevent the barrier coating layer 3 from being lowered. In this way, a part of the wrapping fusion part is used as the non-coating fusion part 91, and the end face exposure prevention treatment is performed there. Then, there is no permeation of the contents, there is no deterioration of the barrier coating layer 4 or productivity, and high performance can be maintained even after processing into a container. In the case of the present invention, unlike the stiff barrier resin film, since it is made of a coating, there is an advantage that such processing is easy to process.

  Although the present invention is as described above, specific examples of the present invention will be described below.

<Example 1>
The paper base material is MC acid-resistant cup base paper manufactured by Oji F-Tex Co., Ltd., basis weight 260 g / m ²
Corona discharge treatment is performed with the coated surface coated with kaolin and starch inside the paper substrate.
The barrier coating layer uses an adhesive WPB-341 (water-based urethane resin) manufactured by Mitsui Chemicals, and has a coating thickness of 3 g / m ² (barrier urethane resin).
The innermost layer is a 30-micrometer pasting of molten polyethylene (low density polyethylene). The outermost layer is bonded with 20 micrometers of molten polyethylene (low density polyethylene). The prototype container is a yogurt paper cup with a capacity of 100 grams.
The paper member is used for both the bottom and side parts. End face is guaranteed by skive hemming method. In the evaluation, the oxygen gas barrier property was measured with a MOCON oxygen permeability measuring device OX-TRAN (registered trademark) 2/61 manufactured by Hitachi High-Technologies Corporation.
The measurement result was 0.5 cc / Package · day, and the barrier property was confirmed.

<Example 2>
The paper base material is MC acid-resistant cup base paper manufactured by Oji F-Tex Co., Ltd., and has a basis weight of 260 g / m ² .
The barrier coating layer was mixed with an adhesive WPB-341 (aqueous urethane resin): biotite: polyvinyl alcohol: isocyanate = 60: 15: 15: 10 manufactured by Mitsui Chemicals, Inc. The coating thickness is 1 g / m ² (mixture of flat powder, polyvinyl alcohol and barrier urethane resin).
The innermost layer is a 30-micrometer pasting of molten polyethylene (low density polyethylene). The outermost layer is bonded with 20 micrometers of molten polyethylene (low density polyethylene). The prototype container is a yogurt paper cup with a capacity of 100 grams. The paper member is used for both the bottom and side parts. End face is guaranteed by skive hemming method.
In the evaluation, the oxygen gas barrier property was measured with a MOCON oxygen permeability measuring device OX-TRAN (registered trademark) 2/61 manufactured by Hitachi High-Technologies Corporation.
As a result of the measurement, the barrier property was confirmed as 0.3 cc / Package · day.

<Example 3>
The paper base material is MC acid-resistant cup base paper manufactured by Oji F-Tex Co., Ltd., basis weight 260 g / m ² .
Corona discharge treatment is performed with the coated surface coated with kaolin and starch inside the paper substrate.
The barrier coating layer is a 25:75 mixed solution of POVAL (registered trademark) 105 (polyvinyl alcohol) manufactured by Kuraray Co., Ltd. and a 25 percent aqueous solution of polyacrylic acid manufactured by Wako Pure Chemical Industries, Ltd. Coating thickness: 2 g / m ² (mixture of polyvinyl alcohol and polyacrylic acid)
The innermost layer is a 30-micrometer pasting of molten polyethylene (low density polyethylene). The outermost layer is bonded with 20 micrometers of molten polyethylene (low density polyethylene). The prototype container is a yogurt paper cup with a capacity of 100 grams. The paper member is used for both the bottom and side parts. End face is guaranteed by skive hemming method.
In the evaluation, the oxygen gas barrier property was measured with a MOCON oxygen permeability measuring device OX-TRAN (registered trademark) 2/61 manufactured by Hitachi High-Technologies Corporation.
The measurement result was 0.1 cc / Package · day.

<Example 4>
The paper base material is MC acid-resistant cup base paper manufactured by Oji F-Tex Co., Ltd., basis weight 260 g / m ² .
As a coating layer on the inner surface side of the paper base material, a water-based barrier urethane resin, Takelac WPB-341 manufactured by Mitsui Chemicals, is coated to a thickness of 2.0 g / m ² .
Furthermore, as a barrier coating layer, Takelac WPB-341, a water-based barrier urethane resin, was double coated on a bamboo base WPB-341 coat of a paper substrate to a thickness of 2.0 g / m ² .
The innermost layer is a 30-micrometer pasting of molten polyethylene (low density polyethylene). The outermost layer is bonded with 20 micrometers of molten polyethylene (low density polyethylene). The prototype sheet was evaluated and measured as it was without using a container.
In the evaluation, the oxygen gas barrier property was measured with a MOCON oxygen permeability measuring device OX-TRAN (registered trademark) 2/61 manufactured by Hitachi High-Technologies Corporation.
The measurement result was 6.0 cc / m ² · day.

<Example 5>
The paper base material is MC acid-resistant cup base paper manufactured by Oji F-Tex Co., Ltd., basis weight 260 g / m ² .
A water-based coating agent MC coat manufactured by Toyo Ink Co., Ltd. was applied to the inner surface side of the paper substrate to a thickness of 0.3 g / m ² using a gravure printing machine.
As a barrier coating layer, a water-based barrier urethane resin, Takerak WPB-341, manufactured by Mitsui Chemicals, was coated with a gravure printing machine at a thickness of 2.0 g / m ² .
The innermost layer is a 30-micrometer pasting of molten polyethylene (low density polyethylene). The outermost layer is bonded with 20 micrometers of molten polyethylene (low density polyethylene). The prototype sheet was evaluated and measured as it was without using a container.
In the evaluation, the oxygen gas barrier property was measured with a MOCON oxygen permeability measuring device OX-TRAN (registered trademark) 2/61 manufactured by Hitachi High-Technologies Corporation.
The measurement result was 0.7 cc / m ² · day.

<Comparative Example 1>
The paper base material is MC acid-resistant cup base paper manufactured by Oji F-Tex Co., Ltd., basis weight 260 g / m ² . Corona discharge treatment is performed with the coated surface coated with kaolin and starch inside the paper substrate. Barrier coating layer is not applied.
The innermost layer is a 30-micrometer pasting of molten polyethylene (low density polyethylene).
The outermost layer is bonded with 20 micrometers of molten polyethylene (low density polyethylene). The prototype container is a yogurt paper cup with a capacity of 100 grams. The paper member is used for both the bottom and side parts. End face is guaranteed by skive hemming method.
In the evaluation, the oxygen gas barrier property was measured with a MOCON oxygen permeability measuring device OX-TRAN (registered trademark) 2/61 manufactured by Hitachi High-Technologies Corporation.
The measurement result was 1 cc / Package · day or more, and it was judged that the transmission was large beyond the measurement limit and the barrier property was poor.

<Comparative Example 2>
The paper base material is a cup base paper manufactured by Nippon Daishowa Paperboard Co., Ltd., and has a basis weight of 250 g / m ² . Corona discharge treatment is performed with the coated surface coated with kaolin and starch inside the paper substrate.
The barrier film layer is coated with A616 made by Mitsui Chemicals as an adhesive on both sides of the polyethylene terephthalate film 12 micrometers, and 30 micrometers (innermost surface) and 15 micrometers (outer) molten polyethylene are bonded together. It was. Thereafter, the paper base material and the barrier film bonded with polyethylene were bonded together by flowing molten polyethylene between them using an extruder lamination machine.
The innermost layer is a 30-micrometer pasting of molten polyethylene (low density polyethylene). At this time, A616 manufactured by Mitsui Chemicals, Inc. was applied as an adhesive.
The outermost layer is bonded with 20 micrometers of molten polyethylene (low density polyethylene). The prototype container is a yogurt paper cup with a capacity of 100 grams.
The paper member is used for both the bottom and side parts. End face is guaranteed by skive hemming method. In the evaluation, the oxygen gas barrier property was measured with a MOCON oxygen permeability measuring device OX-TRAN (registered trademark) 2/61 manufactured by Hitachi High-Technologies Corporation.
The measurement result was 0.5 cc / Package · day, and the barrier property was confirmed. However, as described above, the product has a large environmental load, such as many bonding steps and a large amount of resin used. .

<Comparative Example 3>
The paper base material is MC acid-resistant cup base paper manufactured by Oji F-Tex Co., Ltd., basis weight 260 g / m ² .
A water-based coating agent MC coat manufactured by Toyo Ink Co., Ltd. was applied to the inner surface side of the paper substrate to a thickness of 0.3 g / m ² using a gravure printing machine.
The barrier coating layer was not applied.
The innermost layer is a 30-micrometer pasting of molten polyethylene (low density polyethylene). The outermost layer is bonded with 20 micrometers of molten polyethylene (low density polyethylene). The prototype sheet was evaluated and measured as it was without using a container.
In the evaluation, the oxygen gas barrier property was measured with a MOCON oxygen permeability measuring device OX-TRAN (registered trademark) 2/61 manufactured by Hitachi High-Technologies Corporation.
The measurement result was 1000 cc / m ² · day or more, and it was judged that the transmission was large beyond the measurement limit and the barrier property was poor.

<Comparative Example 4>
The paper base material is MC acid-resistant cup base paper manufactured by Oji F-Tex Co., Ltd., basis weight 260 g / m ² .
A water-based coating agent MC coat manufactured by Toyo Ink Co., Ltd. was applied to the inner surface side of the paper substrate to a thickness of 0.3 g / m ² using a gravure printing machine.
Instead of the barrier coating layer, an aqueous coating agent MC coat manufactured by Toyo Ink Co., Ltd. was applied to a thickness of 0.3 g / m ² using a gravure printing machine.
The innermost layer is a 30-micrometer pasting of molten polyethylene (low density polyethylene). The outermost layer is bonded with 20 micrometers of molten polyethylene (low density polyethylene). The prototype sheet was evaluated and measured as it was without using a container.
In the evaluation, the oxygen gas barrier property was measured with a MOCON oxygen permeability measuring device OX-TRAN (registered trademark) 2/61 manufactured by Hitachi High-Technologies Corporation.
The measurement result was determined to be 1000 cc / m ² · day or more, exceeding the measurement limit, having large transmission and poor barrier properties.

本発明の紙部材は、以上の様に、本発明の紙部材は、製造工程が少なく、紙にバリア性フィルムを貼り合わせるのではなく、湿気や水分の影響を少なくしながら、紙部材にバリア性を付与するもので、生産性が高く、かつ、プラスチックの使用量を最小にしていくことができると共に、廃棄しやすい構成になっているなど、本発明のメリットは大きい。

As described above, the paper member of the present invention has a small number of manufacturing processes, and does not have a barrier film attached to the paper. The advantages of the present invention are great, such as high productivity, minimization of the amount of plastic used, and easy disposal.

1 ... Paper member 2 ... Paper 21 ... Paper edge (inside the container)
3 ... Barrier coating layer 300 ... Coating range 301 ... Uncoated range 4 ... Sealant layer 40 ...・ ・ ・ ・ ・ Surface fusion layer 41 ・ ・ ・ ・ ・ ・ ・ ・ Sealant layer single unit fusion part 42 ・ ・ ・ ・ ・ ・ ・ ・ Sealant end face entrainment part 43 ・ ・ ・ Skiving and hemming processing Fusion part 5 ... Paint 6 ... Flat powder 7 ... Oxygen gas 8 not permeating ...・ Permeating oxygen gas 9 ・ ・ ・ ・ ・ ・ ・ ・ ・ Fusing part 91 ・ ・ ・ ・ ・ ・ ・ ・ Width a of non-coating range ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Front surface of paper b ・ ・ ・ ・ ・ ・ ・ ・ ・ Surface on which paper content comes into contact (coating surface)
c ... Paint surface (coat layer surface)

Claims (14)

  A paper member, wherein a barrier coating layer and a sealant layer are provided on the paper surface on which the contents are in contact.   The paper member according to claim 1, wherein the paper is coated paper, and a barrier coating layer is provided on the coated surface.   The paper member according to claim 1 or 2, wherein a molten polyethylene resin layer is used as the sealant layer.   As the barrier coating layer, a barrier urethane resin, a barrier acrylic resin, a mixture of flat powder and vinyl alcohol resin, a mixture of flat powder and barrier acrylic resin, or a barrier urethane resin and barrier acrylic resin The paper member according to claim 1, wherein at least one layer of the mixture is provided.   The paper member according to claim 4, wherein the flat powder is an inorganic layered mineral, and is mica, metamorphic rock mainly composed of mica, and water-swellable synthetic mica.   Mixed resin whose barrier urethane resin is mainly composed of an aqueous polyurethane resin (A) containing a polyurethane resin having an acid group and a polyamine compound, a water-soluble polymer (B), and a flat powder (C). The paper member according to claim 4, wherein the paper member is.   The barrier acrylic resin is a mixed resin of an aqueous coating liquid containing a poly (meth) acrylic acid polymer, a polyalcohol polymer, and an aqueous medium, according to any one of claims 4 to 6. Paper member.   The paper member according to claim 6, wherein the water-soluble polymer (B) is a polyvinyl alcohol resin having a saponification degree of 95% or more and a polymerization degree of 300 to 2000.   The paper member according to claim 7, wherein the aqueous coating solution contains a plasticizer.   A paper container having a body part and a bottom part made of the paper member according to claim 1, wherein the body part has a winding and fusing part.   The paper container according to claim 10, wherein no barrier coating layer is provided on an edge of the paper member of the winding drum.   The paper container according to claim 11, wherein the width of the region where the barrier coating layer is not provided on the edge of the paper member of the winding drum portion is shorter than the fusion width of winding and fusing.   The paper container according to any one of claims 10 to 12, wherein an edge of the paper member of the winding drum portion is skived and hemmed.   The edge of the paper member of the winding drum is obtained by previously punching the periphery of the winding and fusing part, bonding a fusible thermoplastic resin, and covering the edge with a thermoplastic resin layer. The paper container in any one of 10-12.

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