JP2016014209A - Pattern paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide pattern paper which has excellent printability owing to high falling prevention of a crushed product and has excellent beautiful decorative properties by suppressing a lowering of visibility of a crushed product or the like.SOLUTION: Pattern paper includes a combination paper layer composed of three or more layers including a first paper layer positioned at the surface and a second paper layer laminated immediately under the first paper layer by combination paper making. The basis weight of the first paper layer is 5 to 25 g/m; the second paper layer contains a dry separated product of a plant; and the content of the dry separated product is 0.5 to 20 mass% of the whole of the second paper layer. The ash content of the first paper layer is preferably 1.5 mass% or lower. Alternatively, the ash content of the first paper layer is preferably higher than 1.5 mass% and 5.5 mass% or lower.

Description

  The present invention relates to a pattern paper.

  2. Description of the Related Art Conventionally, there has been known a paper in which a pattern is formed on a paper by containing pulverized material such as coffee bean koji in the paper as a pattern paper (see JP-A-4-82999). In such a pattern paper, the pulverized product may be exposed on the surface of the paper, and even when it is not exposed, the entanglement between the pulverized product and the pulp fibers forming the paper is low. For this reason, the pulverized product easily falls off due to friction, printing, processing, etc., especially when printing is performed on the surface of the pattern paper, the chipping of the crushed product, adhesion to other parts, damage to the printing plate There is an inconvenience that is likely to occur.

  For the above inconvenience, by adding a paper strength enhancer, starch, PVA, etc., the pulverized material is fixed in the paper layer, or the paper strength enhancer is size-pressed to coat the surface of the pattern paper. Further, it is said that dropping of the pulverized product can be reduced (see JP-A-6-235198). However, with these techniques, the printability tends to be impaired by the solidification of the paper layer, and the reduction of pulverized material exposed on the paper surface is still insufficient.

JP-A-4-82999 JP-A-6-235198

  The present invention has been made in view of the above inconveniences, and an object thereof is to provide a pattern paper that is excellent in printability due to the high fall-off prevention property of the pulverized product, and further excellent in cosmetic properties due to suppression of a decrease in visibility of the pulverized product. And

  As a result of intensive studies in order to solve the above problems, the present inventor has three or more paper layers, and the basis weight of the first paper layer located on the surface is within a specific range. The 2nd paper layer laminated | stacked immediately under a layer contains the dry pulverized material of a plant, The pattern paper in which content of the dry pulverized material of the said plant is in a specific range, it is difficult for the pulverized material in a pattern paper to fall off. As a result, the present inventors have found that it is a pattern paper that is excellent in printability and that is easy to visually recognize a pulverized product or the like and that is excellent in cosmetics, and has completed the present invention.

The invention made in order to solve the above-mentioned problem is a three- or more-layered paper including a first paper layer positioned on the surface and a second paper layer laminated by direct bonding immediately below the first paper layer. A patterned paper comprising a layer, wherein the basis weight of the first paper layer is 5 g / m ² or more and 25 g / m ² or less, the second paper layer contains a dry pulverized product of the plant, and the plant is dried. The patterned paper is characterized in that the content of the pulverized product is 0.5% by mass or more and 20% by mass or less of the entire second paper layer.

  The pattern paper includes a first paper layer located on the surface and a second paper layer laminated by lamination just below the first paper layer. , Also referred to as “pulverized material”), the falling of the pulverized material contained in the second paper layer can be greatly reduced, and printing defects and the like can be greatly reduced. Moreover, the said pattern paper makes the transparency of a 1st paper layer high by making the basic weight of a 1st paper layer into the said range, and it becomes easy to visually recognize the crushed material contained in a 2nd paper layer. Therefore, the pattern paper is excellent in cosmetics. Furthermore, by setting the content of the pulverized material contained in the second paper layer of the pattern paper within the above range, the pulverized material drop-off reducing performance is improved while maintaining the above-described cosmetics. In addition, since the pulverized material of the pattern paper is derived from a plant and plastically deforms at a lower pressure than the pulverized material derived from minerals, etc., the pulverized material is deformed by a flattening process using a calendar or the like after papermaking. The surface of the surface tends to be flat. Therefore, the pattern paper is excellent in printability.

  The ash content of the first paper layer is preferably 1.5% by mass or less. Thus, the transparency and printing strength of a 1st paper layer can be improved more by making the ash content of a 1st paper layer into the said range. Therefore, falling off of the pulverized product can be further reduced while enhancing the cosmetics.

  The ash content of the first paper layer is preferably more than 1.5% by mass and not more than 5.5% by mass. Thus, the transparency and printing strength of a 1st paper layer can be improved more by making the ash content of a 1st paper layer into the said range. Therefore, falling off of the pulverized product can be further reduced while enhancing the cosmetics.

  The first paper layer contains hardwood bleached kraft pulp (LBKP), and the content of LBKP is preferably 60% by mass or more and 100% by mass or less. Thus, by setting the content of LBKP in the first paper layer within the above range, even if pulp such as softwood bleached kraft pulp (NBKP) is blended in the first paper layer, the transparency of the first paper layer is increased. Can keep. Therefore, the strength can be improved while maintaining the above-mentioned performance such as cosmetics.

  The blank paper opacity of the first paper layer is preferably 40% or more and 60% or less. Thus, by setting the blank paper opacity of the first paper layer within the above range, the printability and transparency of the first paper layer can be balanced, and the above performances such as cosmetics can be further improved. .

Here, the basis weight (unit: g / m ² ) is a value measured according to JIS-P-8124: 2011 “Paper and paperboard—Measurement method of basis weight”.

  Ash content (unit: mass%) is a value evaluated in accordance with JIS-P-8251: 2003 “Paper, paperboard and pulp-ash content test method—525 ° C. combustion method”.

  The blank paper opacity (unit:%) is a value evaluated in accordance with JIS-P-8149: 2000 “Paper and paperboard—Opacity test method (paper backing) —diffuse illumination method”.

  As described above, the pattern paper is excellent in printability due to the high fall-off prevention property of the pulverized product, and also has excellent cosmetic properties due to the suppression of a decrease in visibility of the pulverized product. Therefore, the pattern paper can be suitably used for packaging bags such as handbags and packaging materials such as cardboard.

<Pattern paper>
The pattern paper has a multilayer structure formed by combining three or more layers. This multi-layer structure is a three or more paper layer including a first paper layer located on the surface and a second paper layer laminated immediately below the first paper layer. Paper layers other than the first paper layer and the second paper layer (hereinafter, also referred to as “other paper layers”) are laminated by sheeting just below the second paper layer. That is, the first paper layer, the second paper layer, and the other paper layers are sequentially laminated and laminated in order from the surface side.

  As an upper limit of the number of layers of the pattern paper, 6 layers are preferable and 5 layers are more preferable. If the number of layers is 7 or more, the production process may be complicated.

[First paper layer]
The first paper layer is a paper layer located on the surface of the pattern paper. Examples of the raw fiber for the first paper layer include wood pulp, waste paper pulp, non-wood pulp, and synthetic fiber. Further, the first paper layer may contain other papermaking chemicals as long as the effects of the present invention are not impaired.

(Raw fiber)
As the wood pulp, chemical pulp such as hardwood bleached kraft pulp (LBKP), softwood bleached kraft pulp (NBKP), hardwood unbleached kraft pulp (LUKP), softwood unbleached kraft pulp (NUKP), stone ground pulp (SGP) , Pressurized Stone Grand Pulp (PGW), Refiner Grand Pulp (RGP), Chemi Grand Pulp (CGP), Thermo Grand Pulp (TGP), Grand Pulp (GP), Thermo Mechanical Pulp (TMP), Chemi Thermo Mechanical Pulp (CTMP) ) And mechanical pulp such as refiner mechanical pulp (RMP).

  Examples of the waste paper pulp include tea waste paper, craft envelope waste paper, magazine waste paper, newspaper waste paper, leaflet waste paper, office waste paper, corrugated waste paper, Kamihaku waste paper, Kent waste paper, imitation waste paper, land ticket waste paper, refurbished waste paper, and these waste papers And deinked pulp (DIP) that has been deinked.

  Examples of the non-wood pulp include linter pulp, hemp, bagasse, kenaf, esparto grass, bamboo, and straw.

  Examples of the synthetic fibers include polyvinyl alcohol fibers, polyester fibers such as polyethylene terephthalate, polyamide fibers such as nylon, cellulose fibers such as acetate, protein fibers such as promix, and cellulose regenerated fibers such as rayon. Acrylonitrile fiber, carbon fiber, polyolefin fiber, vinylon fiber and the like.

  As raw material fibers for the first paper layer, from the viewpoint of achieving both strength and transparency, wood pulp subjected to bleaching treatment is preferable, and LBKP and NBKP are more preferable. As a 1st paper layer, only 1 type of these raw material fibers may be used, and 2 or more types may be mixed and used for them.

  As content of LBKP in a 1st paper layer, 100 mass% is preferable, 70 mass% or more and 100 mass% or less are more preferable, 80 mass% or more and 100 mass% or less are more preferable. Thus, by setting the content of LBKP in the first paper layer within the above range, the printability, transparency, and strength of the first paper layer can all be at a high level.

(Other papermaking chemicals)
Examples of the other papermaking chemicals include sizing agents, paper strength enhancers, yield improvers, fillers, pigments, and dyes.

  Examples of the sizing agent include known sizing agents such as rosin size, alkyl ketene dimer (AKD), alkenyl succinic anhydride (ASA), and polyvinyl alcohol (PVA). Further, the content of the sizing agent in the first paper layer is preferably 5 kg / t or more and 15 kg / t or less, and more preferably 7 kg / t or more and 12 kg / t or less.

  Examples of the paper strength enhancer include a dry strength enhancer and a wet strength enhancer. Examples of the dry strength enhancer include cationic starch, amphoteric starch, polyacrylamide (PAM), and carboxymethyl cellulose (CMC). Examples of the wet paper strength enhancer include polyamide / epichlorohydrin resin, urea resin, acid colloid / melamine resin, thermal crosslinkability imparting PAM, and the like. The charge of the paper strength enhancer is not particularly limited, and any of cationic, anionic or amphoteric may be used. Further, the content of the paper strength enhancer in the first paper layer is preferably 5 kg / t or more and 15 kg / t or less, and more preferably 7 kg / t or more and 12 kg / t or less.

  Examples of the filler include regenerated particles, light calcium carbonate, heavy calcium carbonate, kaolin, clay, talc, calcium sulfate, barium sulfate, titanium dioxide, titanium oxide, zinc oxide, zinc sulfide, satin white, aluminum silicate, diatomaceous earth. Soil, calcium silicate, magnesium silicate, synthetic silica, aluminum hydroxide, alumina, lithopone, zeolite, magnesium carbonate, magnesium hydroxide and other inorganic fillers; styrene plastic pigments, acrylic plastic pigments, polyethylene, microcapsules, urea / Organic fillers such as formalin resin and melamine resin.

The basis weight of the first paper layer is 5 g / m ² or more and 25 g / m ² or less, more preferably 6 g / m ² or more and 23 g / m ² or less, and further preferably 7 g / m ² or more and 20 g / m ² or less. . If the basis weight of the first paper layer exceeds the above upper limit, the crushed material contained in the second paper layer may be difficult to visually recognize. Conversely, if the basis weight of the first paper layer is less than the above lower limit, the strength of the first paper layer may be insufficient.

It is preferable to reduce the ash content of the first paper layer as much as possible from the viewpoint of ensuring visibility and printability. The upper limit of the ash content of the first paper layer when the basis weight of the first paper layer is more than 20 g / m ^{2 and} 25 g / m ² or less is preferably 1.5% by mass, and more preferably 1.2% by mass. On the other hand, the lower limit of the ash content of the first paper layer is preferably 0.1% by mass, and more preferably 0.2% by mass.

The upper limit of the ash content of the first sheet layer in the first case the basis weight of the paper layer is 5 g / ^{m 2} or more 20 g / ^{m 2} or less, preferably 5.5 wt%, and more preferably 5 mass%. On the other hand, the ash content of the first paper layer is preferably more than 1.5% by mass, more preferably more than 1.6% by mass.

  When the ash content of the first paper layer exceeds the above upper limit, the surface strength of the first paper layer is lowered, and there is a possibility that the printability of the pattern paper becomes insufficient. Moreover, there exists a possibility that the pulverized material contained in a 2nd paper layer may become difficult to visually recognize. In particular, when used paper pulp or non-wood pulp is used as a raw material for the first paper layer, it is necessary to adjust the amount of these pulps used in consideration of the ash content from the used paper and non-wood fibers. Conversely, if the ash content of the first paper layer is less than the lower limit, the production cost of the pattern paper may increase.

  The blank paper opacity of the first paper layer is preferably 40% to 60%, more preferably 45% to 60%, and still more preferably 50% to 60%. If the white paper opacity exceeds the upper limit, the original function as a transparent paper may be difficult to obtain. On the other hand, when the blank paper opacity is less than the lower limit, the print information provided on the surface side of the first paper layer overlaps with the pattern produced by the pulverized product of the second paper layer, and the manifestation of the print information may be impaired. There is.

[Second paper layer]
A 2nd paper layer is a layer laminated | stacked directly under the back surface side of the said 1st paper layer, and contains the dry ground material of a plant. Examples of the raw fiber for the second paper layer include the same fibers as those exemplified in the first paper layer. In addition, the second paper layer may contain other papermaking chemicals as long as the effects of the present invention are not impaired.

  The raw fiber for the second paper layer is preferably wood pulp or non-wood pulp, more preferably chemical pulp or linter pulp. When wood pulp is used as the raw material fiber for the second paper layer, the strength of the second paper layer is increased, so that the pattern paper can be suitably used for a cardboard box or the like. On the other hand, when non-wood pulp is used as the raw fiber for the second paper layer, the flexibility of the second paper layer is increased, and therefore the pattern paper can be suitably used for a handbag or the like.

  Examples of other papermaking chemicals that can be contained in the second paper layer include those exemplified in the first paper layer. The content of the sizing agent in the second paper layer is preferably 5 kg / t or more and 13 kg / t or less, and more preferably 7 kg / t or more and 11 kg / t or less. The content of the paper strength enhancer in the second paper layer is preferably 5 kg / t or more and 15 kg / t or less, and more preferably 7 kg / t or more and 12 kg / t or less. The content of the yield improver in the second paper layer is preferably 10 kg / t or more and 25 kg / t or less, and more preferably 12 kg / t or more and 20 kg / t or less.

  The dried pulverized product of the plant contained in the second paper layer is different in the adsorptivity of chemicals from the raw fibers of the first paper layer and the second paper layer. For this reason, by reducing the content of the sizing agent in the second paper layer to be less than the content of the sizing agent in the first paper layer, it is possible to reduce the size unevenness of the first paper layer by combining and suitable printability. Can be secured.

  Similarly, by making the content of the paper strength enhancer in the second paper layer less than the content of the paper strength enhancer in the first paper layer, the flexibility of the second paper layer can be ensured and the calendar or the like can be flattened. The flatness of the pattern paper by the treatment can be suitably ensured, and the printability can be improved.

  Moreover, the 2nd paper layer may be colored from a viewpoint of improving cosmetics. Examples of the coloring method include a method of adding a dye, a pigment and the like to the raw fiber. Examples of the dye and pigment include those usually used for dyeing paper.

The basis weight of the second paper layer is preferably 15 g / m ² or more and 50 g / m ² or less, and more preferably 18 g / m ² or more and 48 g / m ² or less. If the basis weight of the second paper layer exceeds the above upper limit, the thickness of the pattern paper may be unnecessarily enlarged. Conversely, when the basis weight of the second paper layer is less than the lower limit, the strength of the second paper layer may be insufficient.

(Dry plant pulverized product)
The dried pulverized product of the plant is contained in the second paper layer. This pulverized product is visible from the surface side of the pattern paper through the first paper layer. Thereby, the cosmetics property of the said pattern paper improves. Further, since the pulverized product is derived from a plant, it is more likely to be plastically deformed than a pulverized product derived from a mineral or the like. As a result, the pulverized material is deformed by a calendar process in a normal papermaking process, and the smoothness of the surface of the pattern paper is improved. Therefore, an additional process for improving printing suitability is not required, and a pattern paper excellent in printing suitability can be obtained at a low cost.

  The pulverized product is not particularly limited as long as it is plant-derived and can be pulverized to the extent that it can be added to paper. For example, fruit and vegetable coats, fruit and vegetable stalks, fruit and vegetable seeds, grains Non-food parts such as the outer cover, tea leaves, and coffee bean extraction residues. Among these, tangerine husk, tangerine seed, peach seed, strawberry seed, banana fiber obtained from banana stem, tea husk and coffee beans are preferred. These non-edible parts can be obtained in large quantities in the process of harvesting crops and the like and the process of processing crops and the like into foods and are easy to process. Therefore, the pattern paper can be manufactured at low cost. As the coffee beans, beans roasted, residues after extracting coffee from the roasted beans, silver skin and the like can be used, and among these, silver skin is preferable.

The particle size of the pulverized product is preferably from 0.5 mm to 10 mm, more preferably from 1 mm to 7 mm, and even more preferably from 2 mm to 5 mm. When the particle size of the pulverized product exceeds the above upper limit, the unevenness of the surface of the pattern paper becomes large, and there is a possibility that printing suitability may be reduced. On the other hand, when the particle size of the pulverized product is less than the lower limit, the pulverized product is difficult to visually recognize and may have poor cosmetic properties. Here, the particle size is a value obtained by observing the pattern paper visually and with an optical microscope and averaging the diameters of the minimum circumscribed circles of each pulverized product within 5 cm ² .

  The content of the pulverized product is 0.5% by mass or more and 20% by mass or less of the entire second paper layer, more preferably 2% by mass or more and 18% by mass or less, and further more preferably 5% by mass or more and 15% by mass or less. preferable. When the content of the pulverized product exceeds the above upper limit, the pulverized product may easily fall off. On the other hand, when the content of the pulverized product is less than the above lower limit, the cosmetic properties of the pattern paper may be difficult to improve.

  The pulverized product may be bleached. In the case where the pulverized product is dark, bleaching and making it light can make printed characters and the like clearer and improve cosmetics. As chemicals used for this bleaching, those usually used for bleaching can be adopted, and examples thereof include sodium hypochlorite.

  Examples of the method for producing the pulverized product include a method in which a plant is dried and pulverized using a hammer mill, ball mill, sand mill, coffee mill or the like. Moreover, you may grind | pulverize using the single disc refiner, the double disc refiner, etc. which are used for the beating process of pulp. Furthermore, what dried the plant may be added to the said raw material fiber, and the dried material of a plant may be grind | pulverized with a raw material fiber by performing the beating process of a pulp after that.

[Other paper layers]
The other paper layer is a layer laminated immediately below the back surface side of the second paper layer. The other paper layer reduces the falling off of the dried pulverized plant from the back side of the second paper layer. Examples of the other raw material fibers for the paper layer include the same fibers as those mentioned in the first paper layer. Further, the other paper layer may contain other papermaking chemicals as long as the effects of the present invention are not impaired.

  The other paper layer may be only one layer or a plurality of layers. When the other paper layer is a plurality of layers, these layers may be the same or different.

  Waste paper pulp is preferred as the other fiber for the paper layer. By using waste paper pulp for the other paper layers, the pattern paper can be produced at low cost.

  Examples of other papermaking chemicals that can be contained in other paper layers include the same ones as exemplified in the first paper layer. The sizing agent content in other paper layers is preferably 5 kg / t or more and 13 kg / t or less, and more preferably 7 kg / t or more and 11 kg / t or less. The content of the yield improver in the other paper layers is preferably 20 kg / t or more and 40 kg / t or less, and more preferably 25 kg / t or more and 35 kg / t or less.

  The content of the paper strength enhancer in other paper layers is preferably 5 kg / t or more and 15 kg / t or less, and more preferably 7 kg / t or more and 12 kg / t or less. In addition, when the other paper layers are a plurality of layers, it is preferable that only the outermost layer (the layer located on the backmost side of the pattern paper) contains the paper strength enhancer. Thus, only the outermost layer contains the paper strength enhancer, so that the strength of the pattern paper can be maintained while suppressing the amount of the paper strength enhancer used, and the cost for manufacturing the pattern paper can be reduced. Can do.

The basis weight per other layer of the other paper layers is preferably 20 g / m ² or more and 55 g / m ² or less, more preferably 22 g / m ² or more and 50 g / m ² or less. Thus, the intensity | strength and workability of the said pattern paper improve both by making the basic weight per 1 of other paper layers into the said range.

  Also, the other paper layers can be the same as the first paper layer or the second paper layer. In this case, the content and basis weight of suitable raw material fibers and other papermaking chemicals are the same as those of the first paper layer and the second paper layer. Specifically, among the other paper layers, the paper layer positioned closest to the back surface is the same as the first paper layer, and the layer positioned inside the paper layer positioned closest to the back surface is the second. It is preferably the same as the paper layer. Thus, by providing the paper layer containing the pulverized material and the paper layer covering the outside thereof on the back side, the patterned paper is excellent in cosmetics and the like on both the front and back sides.

[Coating layer]
The said pattern paper may have a coating layer in the range which does not inhibit visibility. This coating layer can be formed by coating, spraying, etc. the coating liquid on the pattern paper. Further, the coating layer may be laminated on the surface of the first layer and the back surface of the outermost layer, or may be laminated only on either one of the surface of the first layer or the back surface of the outermost layer. Moreover, you may laminate | stack between each paper layer of the said pattern paper.

  Examples of the apparatus used for the coating include a size press, a blade metering size press, a rod metalling size press, a blade coater, a bar coater, a gate roll coater, a rod coater, and an air knife coater. Moreover, as a method used for the said spraying, a well-known spray apparatus etc. can be used, for example.

(Coating fluid)
Examples of the form of the coating liquid include solutions and emulsions. Examples of the coating agent contained in the coating solution include an external paper strength enhancer, a surface sizing agent, a binder, a pigment, a dye, a fluorescent whitening agent, an antifoaming agent, a colorant, and a water retention agent. Can be mentioned.

  The coating liquid preferably contains a surface sizing agent. When the coating liquid contains the surface sizing agent, it is possible to further reduce the falling of the pulverized material from the pattern paper. Examples of such a surface sizing agent include the same sizing agents as exemplified in the first paper layer. Of these, polyvinyl alcohol (PVA) is preferred.

  As content of the surface sizing agent in the said coating liquid, 0 mass% or more and 5 mass% or less are preferable, and 0 mass% or more and 2 mass% or less are more preferable. By setting the content of the surface sizing agent in the above range, both printing suitability and cosmetics can be at a high level while reducing dropout of the pulverized product.

<Physical properties of patterned paper>
The basis weight of the pattern paper is preferably 40 g / m ² or more and 600 g / m ² or less, more preferably 50 g / m ² or more and 500 g / m ² or less, and still more preferably 60 g / m ² or more and 300 g / m ² or less. Thus, there exists a tendency for the intensity | strength of the said pattern paper to improve by making the basic weight of the said pattern paper into the said range.

The water absorption at a contact time of 120 seconds on the pattern paper surface is preferably 20 g / m ² or more and 100 g / m ² or less, and more preferably 40 g / m ² or more and 80 g / m ² or less. Further, the water absorption at the contact time of the back surface of 120 seconds is preferably 20 g / m ² or more and 100 g / m ² or less, and more preferably 40 g / m ² or more and 80 g / m ² or less. By making the said water absorption degree into the said range, the strength fall accompanying the careless wetting of the said corrugated sheet paper can be reduced. Here, the water absorption (unit: g / cm ³ ) is evaluated according to JIS-P-8140: 1998 “Paper and paperboard—Water absorption test method—Cobb method”.

  The tear strength in the longitudinal direction of the pattern paper is preferably 800 mN or more and 1,500 mN or less, more preferably 900 mN or more and 1,400 mN or less. On the other hand, the tear strength in the transverse direction of the pattern paper is preferably 900 mN or more and 1,600 mN or less, more preferably 1,000 mN or more and 1,500 mN or less. Thus, there exists a tendency for the intensity | strength of the said pattern paper to improve by making the tear strength of the said pattern paper into the said range. Here, the tear strength (unit: mN) is evaluated according to JIS-P-8116: 2000 “Paper—Tear Strength Test Method—Elmendorf Tear Tester Method”.

  The tensile strength in the longitudinal direction of the pattern paper is preferably 2 kN / m or more and 12 kN / m or less, and more preferably 4 kN / m or more and 8 kN / m or less. On the other hand, the tensile strength in the horizontal direction of the pattern paper is preferably 0.8 kN / m or more and 6 kN / m or less, and preferably 1.2 kN / m or more and 4.5 kN / m or less. Thus, there exists a tendency for the intensity | strength of the said pattern paper to improve by making the tensile strength of the said pattern paper into the said range. Here, the tensile strength (unit: kN / m) is evaluated according to JIS-P-8113: 2006 “Paper and paperboard—Test method of tensile properties—Part 2: Constant speed extension method”.

  The interlayer strength of the pattern paper is preferably 80 mJ or more and 150 mJ or less, and more preferably 90 mJ or more and 130 mJ or less. If the interlayer strength of the pattern paper exceeds the above upper limit, the flexibility of the pattern paper may be reduced. Conversely, if the interlayer strength of the pattern paper is less than the lower limit, the strength of the pattern paper may be insufficient. Here, the interlayer strength (unit: mJ) is measured using an internal bond tester according to TAPPI UM403.

  The sizing degree of the pattern paper is preferably 20 seconds to 100 seconds, and more preferably 40 seconds to 95 seconds. If the sizing degree of the pattern paper exceeds the upper limit, processing such as printing and adhesion may be difficult. On the contrary, when the sizing degree of the pattern paper is less than the lower limit, the pattern paper is likely to get wet with water and may be difficult to use as a packaging material. Here, the sizing degree (unit: second) is evaluated in accordance with JIS-P-8122: 2004 “Paper and paperboard—Sizing degree test method—Stechtit method”.

  The surface strength on the surface of the pattern paper is preferably 5A or more, and more preferably 7A or more. On the other hand, the surface strength on the back surface of the pattern paper is preferably 3A or more, and more preferably 5A or more. When the surface strength is less than the lower limit, printability may be reduced. Here, the surface strength (unit: A) is measured using an IGT printer in accordance with TAPPI UM591.

The proportion of the pulverized product on the surface of the pattern paper (area ratio of the pulverized product) is preferably 2% by mass to 50% by mass, more preferably 2% by mass to 30% by mass, and more preferably 2% by mass to 20% by mass. % Or less is more preferable. If the area ratio exceeds the upper limit, the printed content may be difficult to see. On the other hand, when the area ratio is less than the lower limit, it may be difficult to improve the decorativeness of the pattern paper. In addition, the area ratio of the pulverized material here is JAPAN TAPPI.
No. 43 Measured in accordance with “Paper, paperboard and pulp-contaminant test method”.

<Pattern paper manufacturing method>
The pattern paper manufacturing method includes, for example, a step of preparing a raw pulp slurry (hereinafter also referred to as “slurry preparation step”), a step of manufacturing a dry pulverized product of a plant (hereinafter also referred to as “pulverized product manufacturing step”), A process of adding the dried pulverized product of the plant (hereinafter also referred to as “process of adding pulverized product”) and a process of paper-making the first paper layer, the second paper layer and other paper layers (hereinafter “paper-making process”) (Also called). Hereinafter, each step will be described in detail.

(Slurry preparation process)
In this step, a raw material pulp slurry is obtained by disaggregating and dispersing the raw fiber. At that time, the other papermaking chemicals may be optionally dispersed together with the raw fiber.

  Examples of the disaggregation dispersion method include a method of dispersing raw pulp and other papermaking chemicals in a tank equipped with a stirrer.

  Moreover, when the said raw material fiber is a wood pulp, it is preferable to perform a beating process. By performing the beating process in this manner, the flexibility of the wood pulp is improved. Examples of equipment used for the beating process include refiners and beaters.

(Milled product manufacturing process)
In this step, the pulverized product is produced. As this production method, the methods mentioned in the above-mentioned dry pulverized plant can be employed. Further, as described above, the pulp beating step and the pulverization of the dried plant material may be performed simultaneously.

(Addition process of pulverized materials)
In this step, the pulverized product is added to the raw pulp slurry, or the dried plant product before pulverization is added to the raw fiber. As described above, when the pulp beating step and the pulverization of the dried plant product are performed simultaneously, this step is performed before the pulverized product manufacturing step. Moreover, this process may be performed after the said pulverized material manufacturing process and before a papermaking process. Furthermore, this step may be performed simultaneously with the paper making step. In this case, the raw pulp slurry and the pulverized product are mixed on a paper machine.

(Paper making process)
In this step, the first paper layer, the second paper layer, and other paper layers are sequentially made from the raw pulp slurry, and the patterned paper having a multilayer structure is made together.

  Examples of the papermaking method include an acidic papermaking method, a neutral papermaking method, and an alkaline papermaking method. Examples of the paper machine include a long net paper machine, a twin wire paper machine, a circular net paper machine, and a short net combination paper machine that include, for example, a wire part, a press part, a dryer part, a size press part, and a calendar part. And a circular net paper machine is preferable.

  The patterned paper that has been combined is subjected to drying. Examples of the drying method include hot air heating, gas heater heating, and infrared heater heating.

  It is preferable to perform a calendar process on the pattern paper after drying. By this calendar process, the pattern paper is compressed in the plane direction, and the pulverized material in the pattern paper is deformed. As a result, the flatness of the pattern paper is improved and the printability is improved. Moreover, the transparency of the pattern paper can be adjusted by calendar processing or the like.

  In addition, the method for producing the pattern paper is to apply a coating liquid between the paper layers during the paper making process, or to apply the coating liquid on the surface of the pattern paper or the like after the paper making process. A step of forming (hereinafter also referred to as “coating layer forming step”) may be further provided. When the coating liquid is applied to the surface of the pattern paper or the like, the coating layer forming step may be performed before the calendar process or after the calendar process.

  Process conditions such as temperature, pressure, time, equipment, etc. in the method for producing the pattern paper are appropriately set according to the raw materials used. The number of stages in each process may be performed in one stage or in multiple stages.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated more concretely, this invention is not limited by these. In addition, the evaluation method of quality and performance performed in the present Example is as follows.

<Evaluation method>
[Basis weight (unit: g / m ² )]
Evaluation was performed according to JIS-P-8124: 2011 “Paper and paperboard—Method of measuring basis weight”.

[Ash content (unit: mass%)]
Evaluation was performed in accordance with JIS-P-8251: 2003 “Paper, paperboard and pulp-ash content test method—525 ° C. combustion method”.

[Blank Opacity (Unit:%)]
Evaluation was performed according to JIS-P-8149: 2000 “Paper and paperboard—Opacity test method (backing of paper) —Diffusion illumination method”.

[Occurrence of crushed material]
The falling off of the pulverized product was evaluated visually based on the following criteria.
(Double-circle): There is no omission of a pulverized material.
○: Slight detachment of pulverized material occurred.
(Triangle | delta): The fallen of the pulverized material generate | occur | produced somewhat.
X: A lot of pulverized material dropped off.
In addition, ◎, ○, and Δ were actually usable.

[Proper printing]
The printability of the pattern paper was visually evaluated based on the following criteria.
A: There is no lack of printing.
○: Slight chipping occurred.
Δ: Some printing defects occurred.
×: Many printing defects occurred.
In addition, ◎, ○, and Δ were actually usable.

[Beauty]
The decorativeness of the pattern paper was visually evaluated based on the following criteria.
○: The pulverized product can be visually recognized and is excellent in cosmetics.
X: The pulverized product is difficult to visually recognize and is inferior in cosmetics.
In addition, ○ was actually usable.

<Example 1>
Using the following raw materials, a four-layer pattern paper composed of a first paper layer, a second paper layer, and other paper layers (two layers) was obtained according to the following production method.

[Slurry preparation process]
(Raw material pulp slurry for the first paper layer)
After blending 60% by mass of hardwood bleached kraft pulp (LBKP) and 40% by mass of softwood bleached kraft pulp (NBKP), a raw pulp slurry for the first paper layer was prepared using a double disc refiner.

(Raw material pulp slurry for the second paper layer)
After blending 60% by mass of hardwood bleached kraft pulp (LBKP) and 40% by mass of softwood bleached kraft pulp (NBKP), a double pulp refiner was used to prepare a raw pulp slurry for the second paper layer.

(Other raw material pulp slurry for paper layer)
After mixing kraft waste paper, other paper pulp slurries for paper were prepared using a double disc refiner.

[Crushed product manufacturing process]
A dried product of peach seeds was added to fresh water to prepare a mixed solution having a concentration of 2.5% by mass. This mixed solution was put into a single disc refiner to grind peach seeds.

[Paper making process and pulverized material addition process]
Using these raw pulp slurries, the paper layers of the first paper layer, the second paper layer, and other paper layers were combined with a circular paper machine, and then the water content was adjusted to 51% and mirror finished. It was dried while being pressed against the surface of the Yankee dryer. Furthermore, pattern paper was manufactured while changing the pressure condition of the gloss calendar.

<Examples 2-8 and Comparative Examples 1-8>
Patterned paper was produced in the same manner as in Example 1 except that the raw materials of Example 1 were changed as shown in Tables 1 and 2. The physical properties and evaluation results of this pattern paper are shown in Tables 1 to 3.

  As is clear from the results in Table 3, the pattern paper of the examples reduced the falling off of the pulverized product, and was excellent in printability and cosmetics. On the other hand, the performance of the pattern paper of the comparative example was insufficient.

  As described above, the pattern paper is excellent in printability due to the high fall-off prevention property of the pulverized product, and also has excellent cosmetic properties due to the suppression of a decrease in visibility of the pulverized product. Therefore, the pattern paper can be suitably used for packaging bags such as handbags and packaging materials such as cardboard.

Claims (5)

A pattern paper comprising a first paper layer located on the surface and three or more paper-making layers including a second paper layer laminated by paper-making immediately below the first paper layer,
The basis weight of the first paper layer is 5 g / m ² or more and 25 g / m ² or less,
The second paper layer contains a dry pulverized plant,
The pattern paper, wherein the content of the dried pulverized product of the plant is 0.5% by mass or more and 20% by mass or less of the entire second paper layer.   The pattern paper according to claim 1, wherein the ash content of the first paper layer is 1.5% by mass or less.   The pattern paper according to claim 1, wherein the ash content of the first paper layer is more than 1.5 mass% and not more than 5.5 mass%.   The pattern paper according to claim 1, 2 or 3, wherein the first paper layer contains hardwood bleached kraft pulp, and the content of the hardwood bleached kraft pulp is 60% by mass or more and 100% by mass or less. The pattern paper according to any one of claims 1 to 4, wherein the white paper opacity of the first paper layer is 40% or more and 60% or less.