TW202339658A - Toilet roll - Google Patents

Abstract

To provide a toilet roll that is a long article and has a visible pattern having superior design characteristics, has very few wrinkles and very little sagging, and the surface smoothness of which can easily be felt. The problem is solved by a toilet roll of two-ply toilet paper having a wound roll diameter of 90 to 120 mm, the toilet paper having a single ply weight of 11.0 to 14.0 g/m2, a paper thickness of 60 to 90 [mu]m, unevenness due to embossing, and a pattern formed on one side by solid printing, the pattern having a first solid portion and second solid portion of different colors, the percentage of the total area constituted by the pattern portions being 8 to 20%, the percentage of the total area constituted by the first solid portion being 2.0 to 4.0%, the percentage of the total area constituted by the second solid portion being 6.0% or more, and the toilet roll being obtained by winding the toilet paper that has a length of 65 to 90 m on a paper tube at a roll density of 0.83 to 2.05 such that the surface of the toilet paper having the pattern printed thereon is on the outer layer side thereof.

Description

toilet paper roll

The present invention relates to a roll of toilet paper in which toilet paper is rolled into a roll shape.

Roll toilet paper is a daily necessities for daily consumption. At the same time, toilet space is limited, so the longer roll length is an important factor for consumers to decide to purchase.

The winding length of toilet paper rolls, among popular products commonly used in households, is generally about 25m for double-layer toilet paper called "Double" and about 50m for single-layer toilet paper called "Single". However, in recent years Recently, long products with a length of 1.5 to 3 times this length have also become popular (see Patent Document 1 below).

In order to have a roll diameter that can be used with a commonly used household toilet paper holder for such long toilet paper rolls, the toilet paper needs to have a low basis weight, thin paper thickness, and be tightly wound.

In addition, conventional roll toilet paper with a double layer of about 25 meters and a single layer of about 50 meters sometimes had patterns and other patterns printed on the toilet paper using ink (see Patent Document 2 below). This toilet paper roll has excellent design.

[Prior technical literature] (patent document) Patent Document 1: Japanese Patent Application Publication No. 2018-064664 Patent Document 2: Japanese Patent Application Publication No. 2008-188070

[Problem to be solved by the invention] However, long-size toilet paper rolls require low basis weight, thin paper thickness, and tight winding as mentioned above. Therefore, if the pattern is printed, the ink will strike through. Unnecessary bleeding of ink occurs on the back.

In addition, since ink is applied to a base paper with a thin paper thickness and the winding becomes tight, paper breakage occurs easily during manufacturing and wrinkles, creases, etc. are easily formed.

Furthermore, since the ink is applied to the base paper with a thin paper thickness, the hard texture of the portion where the ink is applied is obvious, and it may be difficult to feel smooth.

Furthermore, roll toilet paper is made by laminating several layers of toilet paper. If it is a long-sized product, the pattern of the lower toilet paper will be too visible, and it may not be possible to achieve the desired design with the pattern. condition.

Therefore, the main problem to be solved by the present invention is to provide a roll toilet paper that is easy to manufacture, has no wrinkles, creases, etc., and can recognize a pattern with excellent design for long-sized toilet paper rolls, and further It is easy to feel the smoothness of the surface.

[Technical means to solve the problem] The first means to solve the above problem is a toilet paper roll, which is to roll double-layer toilet paper into a roll toilet paper with a roll diameter of 90~120mm, and is characterized by: the aforementioned toilet paper, The basis weight of a single layer is 11.0~14.0g/ ^m2 , the paper thickness is 60~90μm, and has unevenness produced by embossing, and has a pattern formed by solid printing on one surface. The aforementioned pattern has a first solid portion and a second solid portion with different colors. The pattern portion accounts for 8 to 20% of the total area. The aforementioned first solid portion accounts for 2.0 to 4.0% of the total area. The aforementioned second solid portion accounts for 2.0 to 4.0% of the total area. The ratio of the portion to the total area is 6.0% or more, and the toilet paper roll is wound on a paper tube with a length of 65 to 90 m and a winding density of 0.83 to 2.05 so that the surface printed with the aforementioned pattern becomes the outer layer side.

The second means relates to the toilet paper roll of the first means, wherein the ten-point average roughness [RzJIS] of the outer layer side of the toilet paper is 0.025 to 0.320 mm.

The third means relates to the toilet paper roll of the above-mentioned first or second means, wherein the toilet paper is two sheets in which a concave portion is formed on one surface and a convex portion is formed on the other surface by embossing. Double-layered, double-embossed toilet paper is a two-layered, double-embossed toilet paper made of sheets stacked so that the concave portion-forming surfaces of these sheets are stacked on the outside.

The fourth means relates to the roll toilet paper of the above-mentioned first to third means, wherein the roll density is 0.1 to 0.3 g/cm ³ .

The fifth means relates to the roll toilet paper of the above-mentioned first to fourth means, wherein the void ratio is 3 to 20%.

[effect] According to the present invention, it is possible to provide a toilet paper roll that is easy to manufacture even if it is a long toilet paper roll, has no wrinkles, creases, etc., can recognize a pattern with excellent design, and can further easily feel the smoothness of the surface. .

Next, the toilet paper roll of the present invention will be described with reference to the drawings. As shown in FIG. 1 , the toilet paper roll 1 of the present invention is formed by winding a double-layered strip-shaped toilet paper 10 around a paper tube (also called a core) 20 in a roll shape.

The roll diameter L2 (diameter) of the toilet paper roll 1 of the present invention is 90 to 125 mm, preferably 110 to 125 mm. If the roll diameter is 90~125mm, it can be easily placed on a general roll stand. Here, the roll diameter L2 is a value measured using a Diameter rule manufactured by Muratec-KDS Co., Ltd. or a tool equivalent thereto. The measured value is an average value measured at three locations where the width direction is changed. Furthermore, the width L1 of the toilet paper roll according to this embodiment is not limited, but is preferably 100 to 130 mm. In addition, the outer diameter L3 of the paper tube is not limited, but is preferably 34 to 42 mmφ.

The toilet paper roll of the present invention is characterized in that the toilet paper has a basis weight of a single layer of 11.0 to 14.0 g/m ² , a paper thickness of 60 to 90 μm, and has unevenness produced by embossing, wherein One side has a pattern formed by solid-printing. The pattern has a first solid portion and a second solid portion with different colors. The pattern portion accounts for 8 to 20% of the total area. The aforementioned pattern The proportion of the first solid part to the total area is 2.0 to 4.0%, the proportion of the second solid part to the total area is more than 6.0%, and the toilet paper has a length of 65 in such a way that the surface printed with the aforementioned pattern becomes the outer layer side. ~90m, winding density 0.83~2.05, wound on paper tube.

Since the toilet paper roll of the present invention has these structures, it is difficult for the ink to bleed through the back when printing the pattern, so that unnecessary bleeding of the ink is less likely to occur on the back and paper breaks are less likely to occur during production. Furthermore, it is possible to obtain a roll of toilet paper that has no wrinkles, creases, etc., furthermore, the pattern of the lower toilet paper is not excessively recognized, and has a unique design. In addition, the hard texture given by the ink is not obvious and it is easy to feel smooth.

Regarding the toilet paper roll of the present invention, the toilet paper wound thereon has a paper thickness of 60 to 90 μm in a single layer state. Preferably it is 60~85μm. If the paper thickness of a single layer is 60~90μm, the toilet paper can have sufficient strength and flexibility. At the same time, when the toilet paper with a length of 65~90m is wound on the paper tube, it is easy to make the roll diameter L2 (diameter) between 90~120mm. within the range. Furthermore, under the pattern printing conditions of the present invention, it is easy to form a roll of toilet paper in which there is no penetration of ink on the back, no unnecessary bleeding of ink on the back, and paper breakage is unlikely to occur during production.

The paper thickness is measured under the conditions of Japanese Industrial Standard JIS P 8111 (1998). After conditioning the humidity of the test piece for more than 8 hours, under the same conditions, use a dial thickness gauge (thickness measuring device) "PEACOCK G" Type" (manufactured by Ozaki Seisakusho Co., Ltd.), measured in a single-layer state. Specifically, first confirm that there is no garbage, dust, etc. between the plunger and the measuring table, then place the plunger on the measuring table, move the scale of the dial thickness gauge to align with the zero point, and then raise it in advance. Plunger and place the test piece on the measuring table, then slowly lower the plunger and read the gauge at this time. During measurement, the plunger is only placed but not pressed. The terminal of the plunger is made of metal and contacts the paper plane in such a way that a circular plane with a diameter of 10 mm is perpendicular to the paper plane. The load when measuring the paper thickness is approximately 70gf. In addition, the paper thickness is the average value obtained by measuring 10 times. In addition, even if unevenness|corrugation is formed in toilet paper by embossing processing, it is measured similarly. In this case, the measurement is performed so that one recessed portion can enter the entire range of the measurement table. The collapse of the concavity and convexity during measurement can be ignored. In this paper thickness measurement, the thickness difference caused by the collapse of the concave portion can be ignored.

Regarding the toilet paper of the present invention, the basis weight of a single layer is 11.0 to 14.0 g/m ² . Preferably it is 11.5~13.5g/m ² . More preferably, it is 12.0~13.0g/ ^m2 . If it is in the range of 11.5 to 14.0 g/m ² , the winding density and void ratio of the toilet paper roll of the present invention can be easily adjusted. In addition, in the toilet paper roll of the present invention, the dry tensile strength, wet tensile strength, etc. may be appropriately adjusted using well-known methods within a range that does not impede the effects of the present invention.

The toilet paper of the present invention has unevenness produced by embossing. When toilet paper is embossed, the toilet paper itself becomes soft and the unevenness on the surface improves the ability to wipe away feces. In addition, if toilet paper is embossed, unevenness will appear on the paper surface, making it difficult to recognize the pattern of the underlying layer through the paper surface, making the design excellent.

In particular, the toilet paper of the present invention may be a single-embossed toilet paper in which unevenness is provided by embossing in a double-layered state. However, it is preferable that a recessed portion is formed on one surface and a recessed portion is formed on the other surface. Double-embossed toilet paper is a double-embossed toilet paper in which two sheets with convex portions formed on one surface are laminated so that the concave portion-forming surfaces of these sheets are on the outside. Double embossed toilet paper is easily produced with regard to the winding density and winding hardness of the present invention. Furthermore, double-embossed toilet paper tends to form gaps between layers, making it more difficult to recognize the pattern of the underlying layer through the paper surface, making it excellent in design. In addition, double-embossed toilet paper has recessed portions formed on both sides, and there is no or little difference between the front and back sides of the laminated sheet. In addition, when both sides are concave parts, the user touches the dome part where the angle between the recessed parts is eased with his fingertips, and touches the front and back surfaces with multiple fingers. The feel is soft, and the smooth surface quality can be felt through the fingertips due to the soft pulp material and the dome portion that creates a gentle angle. Therefore, even if a pattern is formed by solid printing alone, it is difficult for the pattern portion to become hard. In addition, double-embossed toilet paper easily stretches when pulled in the extending direction of the sheet, so it is particularly difficult to produce wrinkles and creases caused during manufacturing.

The specific pattern of the concavities and convexities produced by embossing is not necessarily limited. The embossing pattern can be set to appropriate embossing patterns such as micro embossing, dot embossing, and creative embossing. However, it is desirable that the unevenness produced by embossing is arranged so as not to deteriorate the visibility of the pattern produced by printing. For example, it is desirable to have a pattern in which recessed portions of a base (basis) that are recognized as having nothing to do with the pattern are simply arranged neatly. As a more specific example, a pattern in which a tetragon, a triangle, a polygon, a circle, an ellipse, a tetragonal star formed by extending the four corners of a tetragon, etc. are arranged neatly in the vertical and horizontal directions is desirable. In this pattern, the design of the uneven pattern produced by the embossing process and the design of the printed pattern do not interfere with each other, and the design can be felt to complement each other.

A particularly suitable pattern for concave portions (convex portions) produced by embossing is as shown in Figure 4. On the entire paper, the bottom surface is a square with diagonal L5×diagonal L5=1.0~1.5×1.0~1.5mm. The recessed portion 51 (Fig. 4A), or the approximately square recessed portion 51 (Fig. 4B) with the four corners of the square extending diagonally outward, has a center interval L6 of 4.5~5.5mm and is positioned relative to the width direction They are arranged in a lattice shape so that the arrangement angle is 45°, and there are valley line portions 53 extending from the four corners of the recessed portions between the recessed portions 51 . Furthermore, it is preferable that the valley line portion 53 is gradually and gradually arranged to have an arcuate cross-section so that the four corners of the recessed portion 51 are the deepest and the middle between the recessed portions is the shallowest. This embossed pattern does not reduce the design quality of the pattern produced by printing, and furthermore, it is easy to provide excellent softness and pliability and thus excellent wiping properties of feces. The tension during winding is dispersed by the valley line portion 53 oriented in a direction that makes an angle of 45° with the width direction. Regarding the winding length of the toilet paper roll of the present invention, the tension generated by the embossing process is The unevenness is extremely clear and wrinkles are unlikely to occur.

Here, the desired embossing density in the present invention is 3 to 25 embossings/cm ² , preferably 4 to 20 embossings/cm ² . If the embossing density is 3 to 25 pieces/cm ² , the design properties produced by the embossing and the design properties produced by the pattern produced by the printing of the present invention complement each other, thereby even if the The ratio of the pattern part to the total area is set to less than 10%, and the ratio of the second solid part to the total area is set to 6.0%. The printed pattern is not likely to give a cheap impression and the design can be fully improved. The embossing density is measured using ONE-SHOT3D measurement Macroscopes VR-3200 (model) manufactured by KEYENCE Corporation or an equivalent instrument and image analysis software "VR-H2A" or equivalent software. The measurement was performed under the conditions of a magnification of 12 times and a visual field area of 24 mm × 18 mm. First, measure the area of the range of the embossing group containing a plurality of units that constitute the embossing pattern, and calculate the number of embossings within the range. The so-called "range including a plurality of units of embossing groups" means the smallest unit that can constitute the entire embossing pattern that divides the toilet paper plane into equal areas, or a sealed area that is a plurality of multiples of the smallest unit. Density of embossing (pieces/cm ² ) = (number of embossings in the range containing the embossing group of plural units) ÷ (area of the range including the embossing group of plural units), calculated according to this formula . However, the magnification and the visual field area can be appropriately changed according to the size of the embossing (recessed portion).

On the other hand, the toilet paper of the present invention preferably has a ten-point average roughness [RzJIS] of 0.025 to 0.320 mm on the outer layer side. More preferably, it is 0.025~0.315mm. If the ten-point average roughness [RzJIS] is within this range, printing scratches will be less likely to occur, printing clarity will be better, and design will be easily improved. The ten-point average roughness [RzJIS] is measured using ONE-SHOT3D measurement Macroscopes VR-3200 (model) manufactured by KEYENCE Corporation or an equivalent instrument and image analysis software "VR-H2A" or equivalent software. Determination. The measurement was performed under the conditions of a magnification of 12 times and a visual field area of 24 mm × 18 mm. However, the magnification and the visual field area can be appropriately changed according to the size of the embossing (recessed portion). The ten-point average roughness [RzJIS] is an arbitrary position avoiding the part where the pattern is given with ink, and when there is no embossing process, and when there is a recessed part produced by the embossing process. The method is to avoid the position of the concave part, especially the position of the middle part of the concave part when the concave parts are arranged neatly, take a picture of a three-dimensional image, and analyze the data for measurement. The contour lines measured by line roughness measurement are measured and analyzed in the paper conveyance direction. "Composite parameter RzJIS" should be used for measurement parameters. In addition, since the outermost surface of the toilet paper roll reflects the smoothness of the surface of the toilet paper roll, but the accuracy is low, the measurement position on the toilet paper roll is set to 29 to 31% from the outermost end of the toilet paper roll. Anywhere within range. In addition, the measured value is an average value of 10 points, and the measurement sample can be fixed on the measurement stage using a method that does not affect the measured value.

Furthermore, regarding the toilet paper of the present invention, the number of wrinkles is preferably 35 to 50/10 mm. The number of wrinkles is 35~50/10mm, preferably 37~48/10mm, more preferably 39~45/10mm. If the number of wrinkles is within this range, the surface becomes more likely to feel smooth. In particular, in the above-mentioned pattern printing of the present invention, the hard texture imparted to the ink portion is less likely to become apparent, and the entire surface becomes more likely to feel smooth. The number of wrinkle lines can be adjusted by the wrinkle rate during base paper production, the presence or absence of the calendering process, and the calendering pressure. Furthermore, the number of wrinkles is measured using ONE-SHOT 3D measurement Macroscopes VR-3200 (model) manufactured by KEYENCE Corporation or an equivalent instrument and image analysis software "VR-H2A" or equivalent software. The measurement was performed under the conditions of a magnification of 12 times and a visual field area of 24 mm × 18 mm. However, the magnification and the visual field area can be appropriately changed according to the size of the embossing (recessed portion). The number of wrinkles is measured at any position avoiding the part where the pattern is applied with ink. If there is no embossing process, it is an arbitrary position. The position of the recess, especially the position of the middle part of the recess when the recesses are arranged neatly, is measured by taking a three-dimensional image and analyzing the data. The contour line measured by line roughness measurement is specified, measured, and analyzed perpendicularly to the paper conveyance direction. The measurement parameter applies "line roughness". The number of peaks between the measurement distances of 10 mm in the obtained measurement profile curve was defined as the number of wrinkles. In addition, since the outermost surface of the toilet paper roll reflects the smoothness of the surface of the toilet paper roll, but the accuracy is low, the measurement position on the toilet paper roll is set to 29 to 31% from the outermost end of the toilet paper roll. Anywhere within range. In addition, the measured value is an average value of 10 points, and the measurement sample can be fixed on the measurement stage using a method that does not affect the measured value.

Regarding the toilet paper roll of the present invention, a pattern is printed on one of the surfaces of the toilet paper, and the toilet paper is wound around a paper tube so that the surface on which the pattern is printed becomes the outer layer side. That is, the toilet paper roll of the present invention has a pattern only on the surface located on the outer layer. By printing the pattern on the outer layer side, the pattern can be clearly recognized directly from the outside.

In addition, since the roll of toilet paper has several overlapping layers of toilet paper, if the pattern on the lower layer of more than one layer is transmitted through, the pattern on the lower layer and the pattern on the outer surface may be mixed and recognized. However, since the toilet paper of the present invention is a double layer and has an unprinted layer on the inner layer side, if the basis weight and paper thickness of the single layer are within the range specified in the present invention and only the outer layer is formed, pattern, the pattern on the outer surface can be fully recognized, while the pattern on the underlying layer is difficult to discern. In particular, when double embossing is further utilized and a gap is provided between each layer, the pattern of the lower layer is difficult to recognize. Furthermore, in order to make the pattern exist only on the outer layer side, winding may be performed so that the printed surface becomes the outer side.

The pattern of the present invention is formed by printing and does not include the case where it is already colored in the papermaking stage by processes such as supplying dye to the papermaking raw material. The specific design of the pattern is not particularly limited. For example, the following forms can be exemplified: plants such as flowers, trees, and grass; living things such as humans, animals, fish, shells, and insects; nature such as mountains, rivers, seas, clouds, forests, and forests; and planets such as the moon, sun, and stars. /A form in which one or a plurality of artificial objects such as satellites, cars, airplanes, and trains are appropriately selected and drawn. Although the area of one pattern is not necessarily limited, it is desirably 10.0mm ² to 918mm ² . It is easy to recognize the pattern and feel that the design is excellent. At the same time, the amount of printing ink in one pattern part is not too much and the back is less likely to show through. Therefore, the effects of the present invention are easily manifested.

The pattern of the present invention is formed only by solid printing. Moreover, the pattern portion accounts for 8 to 20% of the total area. Preferably it is 8~10%. The ratio of the total area is the ratio of the pattern part of the toilet paper to the area of one of the surfaces. Furthermore, since the pattern is printed repeatedly at a predetermined pitch during the manufacturing process of toilet paper with printed patterns, the ratio of the pattern portion to the total area is calculated by starting from the front end of the toilet paper excluding the tail seal. Ten samples were cut at intervals of 50 cm, and the ratio of the area of the pattern part in each piece to the area of one of the surfaces (width of toilet paper × 50 cm) was calculated, and the average value of the ten pieces was calculated. The area of the pattern portion in the sample is measured by optically scanning the sample and then measuring it using well-known software.

If the proportion of the pattern portion to the total area is 8 to 20%, the toilet paper will not feel hard due to the ink given to it during use, especially when it is made into other rolls with regard to the winding length, roll diameter, etc. of the present invention. It can prevent wrinkles and creases from occurring when manufacturing with the tension required for the tube structure.

Furthermore, the pattern of the toilet paper of the present invention particularly has a first solid portion and a second solid portion of different colors, that is, it has a solid printed portion of two or more colors. Furthermore, the first physical part may also be plural places. Furthermore, the second physical part may be plural locations. The first solid part in the present invention is one or a plurality of areas that are solidly printed using one kind of ink, and one printing plate is used to form the entire first solid part range. The second solid part in the present invention is one or more areas that are solidly printed using another ink different from the first solid part, and is formed using a printing plate that is different from the first solid part. the entire range. It has two or more colors of solid printing parts, so it is easy to improve the design.

Regarding the pattern of the toilet paper of the present invention, the proportion of the first solid part to the total area is 2.0 to 4.0%, and the proportion of the second solid part to the total area is 6.0% or more. By setting the proportion of the first solid part to the total area to 2.0~4.0% and setting the proportion of the second solid part to the total area to more than 6.0%, the pattern can be clearly recognized and it is difficult to cause problems due to ink transfer. The transparent back ensures design. In addition, the entire toilet paper does not become hard, and wrinkles, creases, etc. are less likely to occur during the production process. Furthermore, when combined with other structures of the present invention to form a roll of toilet paper, the solid part will not be excessively recognized through the non-patterned part of the toilet paper located on the outer side, and the intended expression will be easily recognized. Designed toilet paper roll.

Here, the toilet paper of the present invention has a single layer paper thickness of 60 to 90 μm. In this way, when the thickness of a single layer of paper is thin, especially when the basis weight is low, if halftone printing is performed within the range of about 2.0 to 4.0% of the total area, sufficient pressure will not be applied to the sheet during printing, and there will be marks. A situation where the ink does not adhere to the sheet and the printed part is not clear. In addition, this phenomenon is likely to occur when the area of one pattern is included in the above-mentioned range of 10.0 mm ² to 918 mm ² . In order to improve the adhesion of the ink, just increase the pressure. However, if the pressure between the toilet paper and the printing plate is increased, the operability will deteriorate, such as the operation speed will slow down. Also, the thick feeling of toilet paper may be reduced. Furthermore, if the pressure is too high, the ink will penetrate into the layer on the opposite side to the printing surface and cause back-through. Regarding the toilet paper of the present invention, while forming the pattern only by solid printing, the ratio of the first solid part to the total area is 2.0 to 4.0% and the ratio of the second solid part to the total area is 6.0% or more. This can improve operability stability and transparency problems. In addition, due to the relationship between the double embossing and the basis weight mentioned above, there is no hard texture and wrinkles and creases are unlikely to occur.

The pattern on the toilet paper of the present invention is preferably printed by flexographic printing (relief printing) using aqueous ink. However, gravure printing such as gravure printing, lithographic printing such as offset printing, etc. can also be used. Especially if it is a water-based printing ink, if it is a water-based printing ink with a viscosity of 10 to 50 cps, a color developing agent of 30 to 60 mass %, and a water content of 70 to 40 mass %, the pattern can be fully vivid and even if the water is soaked Paper is also less prone to wrinkles and creases. Furthermore, viscosity is the value measured by a B-type viscometer.

Although the line number of the anilox roller used when printing the pattern of the present invention is not necessarily limited, it is desirably 250 to 600/1 inch, and more preferably 250 to 500/1 inch. This condition is suitable for forming patterns regarding the present invention.

Regarding the toilet paper roll of the present invention, it is a toilet paper having the above-mentioned pattern, and 65 to 90 m of toilet paper is wound on a paper tube with a winding density of 0.83 to 2.05. The winding length of toilet paper is 65 to 90m, which is more than twice as long as the double-layered product of about 25m that is commonly used in ordinary households. Furthermore, the winding length is measured while unwinding the roll of toilet paper without applying tension. For example, the measurement may be performed while folding back in a zigzag pattern every 5 m from the start of unwinding.

Furthermore, the toilet paper roll of the present invention has the above-mentioned winding length and a winding density of 0.83 to 2.05. The preferred range is 0.95~1.45, and the particularly preferred range is 1.00~1.30. The winding density in the present invention is a value calculated from the actual cross-sectional area/theoretical cross-sectional area. The so-called actual cross-sectional area is a value calculated from the winding length x paper thickness. On the other hand, the so-called theoretical cross-sectional area is a value calculated from (roll diameter/2)×(roll diameter/2)×π-(paper tube outer diameter/2)×(paper tube outer diameter/2)×π . In other words, it is the value obtained by deducting the area of the opening end of the paper tube from the area of the end surface. In the case of the above-mentioned winding length, especially roll toilet paper with a winding density in the range of 0.83 to 2.05 is easy to manufacture and has few wrinkles, creases, etc. In addition, when you hold the outer peripheral surface of the roll of toilet paper with your hand, you will feel that it is moderately compact and has a solid winding length, and it is not easy to feel that it is too soft or too hard. If it exceeds 2.05, the texture will tend to feel harder than the actual winding length. On the other hand, if it is less than 0.83, the toilet paper roll will feel too soft relative to the winding length, and it will often be difficult to feel solid.

Regarding the roll toilet paper of the present invention, its winding density is as described above, and the roll density is desirably 0.10 to 0.30 g/cm ³ . More preferably, it is 0.10~0.25g/cm ³ . Roll density is expressed as (roll mass) ÷ (roll volume). Roll quality is the mass of toilet paper per 114mm of roll width. The roll volume is represented by [{the cross-sectional area of the L2 part of the roll diameter (diameter)} - (the cross-sectional area of the L3 part of the outer diameter of the paper tube)] × roll width (converted to every 114 mm). Roll density is also an indicator of roll toilet paper, indicating how dense it is? Whether it is tightly wound or loosely wound. Moreover, if it is too loose, the toilet paper will easily deform excessively near the paper tube and fly out (loosen); and if it is too tight, the toilet paper will feel hard when holding the toilet paper roll.

Furthermore, in the toilet paper roll according to the present invention, the toilet paper roll is double-embossed as described above and has a predetermined basis weight, and the ratio of the pattern portion to the total area is 8 to 20%, and The ratio of the first solid part to the total area is set to 2.0~4.0%, and the ratio of the second solid part to the total area is set to 6.0% or more, whereby the pattern can be fully recognized and even though only solid printing is used to form a transparent However, it is difficult to cause wrinkles and creases on the back, and further wrinkles and creases are very rare. That is, when the winding length is increased and the winding density is increased, when forming the toilet paper roll, it is necessary to increase the tension to wind the toilet paper roll around the paper tube. On toilet paper with a pattern, the stretch of the paper becomes different between the printed part where ink is applied and the non-printed part where ink is not applied. Therefore, if the tension is increased, when the toilet paper becomes roll toilet paper, the paper will stretch differently. Wrinkles, creases, etc. are easy to occur on the toilet paper roll, but in the toilet paper roll of the present invention, such problems are solved. In other words, it is possible to provide roll toilet paper that has excellent pattern recognition and does not show back. When held by hand, the paper has sufficient softness as a product and does not have wrinkles or creases.

Furthermore, the toilet paper roll of the present invention preferably has a void ratio of 3 to 20%. The void ratio (%) in the present invention is a value (actual void ratio of the entire reel) calculated from (actual void volume of the entire reel)/(theoretical reel volume) × 100. The actual void volume of toilet paper roll is a value calculated from (actual cross-sectional area (cm ² )) × (roll width (cm)), and the theoretical roll volume is calculated from (winding length (cm) × 2 × paper thickness The value calculated from (single layer, cm)) × (roll width (cm)). The void ratio (actual void ratio of the entire roll, %) is calculated by ((theoretical roll volume (cm ³ )) - (actual roll volume (cm ³ ))/(theoretical roll toilet paper volume (cm ³ )) It is calculated by The degree of winding and bundling. This indicator can be adjusted by embossing, paper thickness, and winding tightness. The case of thicker paper includes high porosity but excessively deep and strong embossing that is not easy to collapse. When the porosity of the present invention is high, the roll will tend to feel hard, and when the porosity is low, the roll will tend to feel hard. There will be a tendency for the roll to feel soft. Furthermore, if the void ratio exceeds 20%, the backing of the pattern will become obvious and the design of the roll will be difficult to identify. If it is less than 3%, the pattern will feel unclear due to printing scratches. .

Furthermore, regarding the toilet paper of the present invention, the whiteness (whiteness) of the part without pattern printing is 80% or more, and the Lab value obtained by directly measuring the part with pattern printing on the lower layer is consistent with the Lab value obtained by passing through the upper layer of toilet paper without pattern printing. Use the white part to measure the color difference ΔE=((ΔL) ² +(Δa) ² +(Δb) ² ) ^1/2 of the Lab value obtained by printing the pattern. It is hoped that it is within the range below 2.20. Better is less than 2.00. Furthermore, the color difference ΔE' between the Lab value obtained by the pattern printing and the Lab value of the white portion of the upper toilet paper without pattern printing is preferably 6.0 or less. If the whiteness, ΔE, and ΔE' are such, as shown in FIG. 3 , the pattern 40 of the lower layer seen through the white portion without pattern printing on the upper layer of toilet paper will not be recognized excessively and clearly, but It becomes vaguely and slightly identifiable. At the same time, patterns on the upper layer that would be directly recognized become clearly identifiable. Therefore, the contrast between the directly recognized patterns 41 and 42 and the lower pattern 40 that is recognized through the white part of the toilet paper enables a unique and characteristic design to be expressed. In particular, when the pattern printing is 8 to 20%, the pattern range will not be too wide, and the effect produced by the contrast between the printed part and the white part that can be directly recognized and the printed part that is recognized through the upper layer becomes Deco felt appropriate.

Here, regarding the measurement procedure of the whiteness and color difference ΔE, ΔE′ of the present invention, as shown in FIG. 2 , five pieces of white paper 31 are placed on a horizontal measuring table in an overlapping manner, and then placed on top of each other in an overlapping manner. For the sample 33 to be measured, the unpatterned portion of the toilet paper 34 taken from the same toilet paper roll as the sample 33 is overlapped so as to cover the pattern portion 32 of the sample 33 to be measured. Furthermore, the white paper 35 having the windowed portion 36 of 20 mmφ is overlapped thereon so that the pattern portion 32 to be measured can be located within the windowed portion 36 .

Then, from the window portion 36, through the toilet paper 34, the whiteness and Lab value of the pattern portion to be measured are measured with a spectroscopic whiteness/color difference meter (measured from the white portion of the upper toilet paper without pattern printing). Measure the Lab value obtained by printing the above pattern). Next, the toilet paper 34 overlapping the pattern portion 32 is removed so that the measurement location does not move, and the whiteness and Lab value of the pattern portion to be measured are measured with a spectroscopic whiteness/color difference meter (direct measurement of the above-mentioned The Lab value obtained from the printed part of the lower layer). Next, the sample is further removed, and the whiteness and Lab value of the uppermost portion of the stacked five pieces of white board paper 31 (the Lab value of the white portion of the upper layer of toilet paper without pattern printing) are measured with a spectroscopic whiteness/color difference meter. )(blank value). In addition, the spectroscopic whiteness/color difference meter is measured using the spectroscopic whiteness/color difference meter PF7000 manufactured by Nippon Denshoku Industries Co., Ltd. or an equivalent instrument. The color differences ΔE and ΔE' are calculated from the measured Lab values.

The number of colors constituting the pattern provided on the toilet paper of the present invention is not particularly limited as long as it is 2 or more colors. However, from the viewpoint of cost and equipment, and because toilet paper is low-density and easily bleeds out, it is desirably 2 to 3. color. Most appropriately, it is desired to be composed of two colors of the first solid part and the second solid part. In addition, when measuring the Lab value of the above-mentioned pattern, when one pattern has a plurality of colors, all the parts with different colors are measured, and all the measured values are good within the above-mentioned numerical range.

The fiber in the toilet paper of the present invention is not limited, but it is preferable that it is 70 to 100 mass% of original wood pulp and 0 to 30 mass% of recycled pulp. If recycled pulp is blended, it can be produced more cheaply compared to toilet paper composed of 100% by mass virgin wood pulp. In addition, when recycling pulp, in the step of regenerating pulp from recycled paper, the fibers tend to become thinner than the fibers of the pulp before regeneration. Due to the nature of such fibers, the fibers can be reduced without increasing the thickness of the paper. becomes denser and the paper strength tends to become higher. On the other hand, if recycled pulp is blended excessively, texture such as softness will be reduced. Therefore, in view of the characteristics of recycled pulp, it is good to set the blending ratio in the range of 0 to 30% by mass. Furthermore, the type of recycled pulp is not necessarily limited, but recycled pulp using milky white cardboard recycled paper and high-quality recycled paper as raw materials is particularly desirable. These recycled papers are blended with a lot of coniferous kraft pulp (NBKP) derived from raw materials, so paper strength is easy to show.

As the pulp to be used, coniferous tree kraft pulp (NBKP) and broadleaf tree kraft pulp (LBKP) are suitable. The blending ratio of these pulps is preferably NBKP:LBKP of 20:80 to 50:50. NBKP can also be pulp derived from opal board. Furthermore, toilet paper manufactured using fiber materials composed of this virgin wood pulp and the above-mentioned high-quality recycled pulp has a mechanical pulp derived from recycled paper of 5 mass % or less, an ash content of 3 mass % or less, and a whiteness of 80 to 85%. about.

[Winding length elongation (%)] On the other hand, regarding the toilet paper roll of the present invention, the winding length elongation is preferably 1.0 to 3.6%. More preferably, it is 1.6~3.3%, especially 2.0~3.0%. The winding length elongation indicates the elongation of the sheet stretched and wound in the drum.

The measurement of the winding length elongation is based on the winding length L0 and the sheet length L1 (m) in the drum, and is calculated by the winding length elongation (%) = (L1-L0)/L0... equation (1) Pick. Here, the winding length L0(m) is obtained by the following method. The number of sheets is counted in sheet units divided by holes. The winding length is set from the second sheet to the sixth sheet as the first group. The second sheet is the end of the tail seal part of the roll. The sheet next to the outer rolled sheet (the first sheet) is cut with scissors and the like every fifth sheet in succession, and the sheet size is actually measured. Take the last group of the innermost portion in such a way that the last group does not include the pick up portion of 2 slices. The last group at this time is set as the nth group. When actually measuring the sheet size, use a JIS Class 1 metal ruler to actually measure the weight of 5 consecutive sheets (sets) placed on a flat table. First, find the average group length. The average group length is obtained by the average group length (m) = {length of the first group + length of the second group +... + length of the nth group} ÷n... equation (6). The winding length L0 is given by L0(m)=(average group length)×n+(average group length/5)×{1+(the number of innermost rolled sheets including the pickup part and which cannot form a group)}... formula ( 7) Come and ask for it. In addition, the sheet length at the tail seal part and the pick-up part has adhesive attached and wrinkles, so the accurate sheet length cannot be measured, so it is calculated by converting it to (average group length/5).

The sheet length L1 (m) in the roll represents the winding length of the sheet in the roll, and is obtained by the following procedure. (1) Use a magic pen or the like to draw a straight line from the outermost side of the roll to the paper tube and through the central axis of the paper tube on the side of the roll. The outermost mark of the roll (the mark of the strange pen) is aligned with the outermost end of the sheet. (2) Count the number of marks with a singular pen at the width end of the sheet unrolled from the roll, and set it as the number of overlapping layers (double layers) of sheets in the roll. For the amount of sheets that include the pick-up part and cannot form a group, calculate the number of layers using (number of sheets that cannot form a group × average sheet length ÷ [(paper tube outer diameter r) × π]) and total it, Let be the number of lamella layers P. (3) Roll cross-sectional area S (cm ² ) = π/4 × [(roll diameter R) ² - (paper tube outer diameter r) ² ]...Equation (2), S is expressed in cm ² units, roll The cylinder diameter R and the paper tube outer diameter r are expressed in cm. (4) In addition, when the paper thickness of the sheet in the roll state is T (mm), T is obtained by taking the roll cross-sectional area as the area where the sheets are rolled into a roll and laminated. (mm)=1/2×(Rr)/(P×10)…Equation (3) (5) Furthermore, S (cm ² )=length of the sheet in the roll L1 (m)×T (mm)×10 ...Equation (4), T (mm) is the paper thickness of the sheet in the roll (6). Therefore, the length of the sheet in the roll L1 (m) = S (cm ² )/(T (mm) × 10)...Equation ( 5) Therefore, substitute equation (2) and equation (3) to find L1=π/2×(R+r)×P÷100… equation (6) In this way, the winding length of equation (1) The elongation (%) represents the elongation (%) of the sheet wound in a roll while being stretched. The greater the elongation (%), the more it is stretched in the drum.

If the winding length elongation (%) is less than 1.0%, the sheet has high tensile rigidity and is difficult to stretch, resulting in paper that feels hard, and its tensile rigidity requires deeper embossing. Strengthen to ensure that the embossing does not collapse and become a rough surface texture. If the winding length elongation (%) exceeds 3.6%, the tensile rigidity of the sheet is too low, and the sheet easily stretches and becomes a paper that feels excessively soft and loses the feeling of weight and security, and the tensile rigidity is too low. The sheet is elongated and the embossed unevenness is also elongated, causing the embossing to be crushed, which reduces the clarity of viewing the embossing and deteriorates the appearance.

[Example] Next, regarding the Examples and Comparative Examples of the roll toilet paper of the present invention, the "smoothness of the sheet", "smoothness of the roll surface", "prevention of back leakage", "design", and "printing clarity" were confirmed (Including no printing scratches)". Table 1 below shows the structure of the toilet paper roll and the physical properties, composition, and test results of the toilet paper in each example. Comparative Example 5 and Example 6 were formed by winding single-embossed toilet paper. In other Examples and Comparative Examples, two sheets were formed with a concave portion formed on one surface and a convex portion formed on the other surface by embossing, and the concave portion forming surface of these sheets became the outer side. It is made of double-layered double-embossed toilet paper that is laminated in the same way. The embossing pattern in each example is the pattern of the arrangement of the recessed portions in Fig. 4(B). The pattern is based on the combination of flowers and leaves shown in Figure 3, and the area of each pattern is adjusted according to the proportion of the total area.

The smoothness of the sheet was evaluated in the following way: From the toilet paper roll, 2 pitches were taken as 1 pitch between the perforation lines of adjacent toilet paper, and then the subject actually touched the 2 pitches of toilet paper. The smoothness of the sheet surface was evaluated on a scale of 1 to 5 points. Evaluation criteria, regarding smoothness, give 5 points for "satisfied", 4 points for "slightly satisfied", 3 points for "neither", 2 points for "slightly dissatisfied", and 1 point for "dissatisfied" point. The descriptions in Table 1 are the average values rounded to one digit. The number of subjects was 30.

The smoothness of the roll surface was evaluated by a subject actually touching the outer peripheral surface of the roll toilet paper and rating it on a scale of 1 to 5 points. Evaluation criteria, regarding smoothness, give 5 points for "satisfied", 4 points for "slightly satisfied", 3 points for "neither", 2 points for "slightly dissatisfied", and 1 point for "dissatisfied" point. The descriptions in Table 1 are the average values rounded to one digit. The number of subjects was 30.

The back-through prevention property was evaluated in the following manner: A test subject actually visually observed the back side of the printed portion (non-printed portion) corresponding to the outer peripheral surface of the roll toilet paper, and the ink was transferred to the back side (non-printed side) of the toilet paper. side), give 5 points for "cannot see through the back at all", 4 points for "no see through the back", 3 points for "neither", and 3 points for "can see through the back slightly" Give it 2 points, and give 1 point for "the back can be seen", and evaluate based on this evaluation criteria. The descriptions in Table 1 are the average values rounded to one digit. The number of subjects was 30.

Designability is evaluated in the following manner: a subject actually visually observes the pattern from the outer peripheral surface of the toilet paper roll, and determines the appearance conditions such as the balance between the pattern portion and the white portion and the transparency of the underlying pattern. Give 5 points for "very good", 4 points for "excellent", 3 points for "neither", 2 points for "a slightly cheap impression", and 1 point for "a very cheap impression" Points will be assigned based on this evaluation criteria. The descriptions in Table 1 are the average values rounded to one digit. The number of subjects was 30.

The printing sharpness is evaluated in the following manner: The test subject actually visually observes the back side of the printed portion (non-printed portion) of the outer peripheral surface of the toilet paper roll. Regarding the printed portion of the toilet paper (the transfer portion of the ink), Give 5 points for "no scratches but clear", 4 points for "only slightly scratched but generally clear", 3 points for "with scratches but mostly clear", 2 points for "partially scratched but slightly less clear", and 2 points for "some scratches but slightly less clear". "The overall printing is scratched and not clear" is given 1 point, and the points are evaluated based on this evaluation criterion. The descriptions in Table 1 are the average values rounded to one digit. The number of subjects was 30.

[Table 1]

In Examples 1 to 6, although the paper thickness was thinned to increase the length, the total area of the pattern was 8% or more, so the design was sufficient, and the backing was prevented from being shown through solid printing. Especially in the case of double embossing, the evaluation becomes high. On the other hand, Comparative Example 1 was only a single-color solid printed pattern with a total area of 7%, and the design evaluation was very low. Furthermore, the evaluation of printing sharpness was also low. The design evaluation of Comparative Example 3 was also low. The design evaluation of Comparative Example 4 was also low. The result of this low evaluation is related to the fact that the pattern was formed only by solid printing of a single color. In addition, printing flowers and leaves in the same color is considered to affect the evaluation results. Furthermore, the evaluation of printing sharpness (printing scratches) was low. Since the printing range reached 21% of the total area and printing scratches were confirmed, the evaluation was lowered. Also, it was confirmed that there was some back-through. Comparative Example 2, the ratio of the pattern to the total area is within the scope of the present invention, but dot printing is used instead of the second solid part and the ratio of the pattern to the total area is slightly wider, but there is a case of see-through and the evaluation of the printing clarity Low. In addition, Comparative Examples 2 to 4 had a high basis weight and a low evaluation of the softness of the sheet and roll. In Comparative Example 6, halftone printing was used instead of the second solid portion and the ratio of the pattern to the total area was reduced. However, there was a case of see-through and the evaluation of printing clarity was low. Poor operability.

On the other hand, Comparative Example 5 is a single-embossed toilet paper with a high basis weight. The smoothness of the sheet and the smoothness of the roll surface were evaluated low, and the printing clarity and transparency were evaluated low. This low evaluation result is considered to be due to the roughness of the surface.

In particular, good results can be obtained by trying double-embossed toilet paper whose ten-point average roughness [RzJIS] is within the range of the present invention from the perspective of printing sharpness.

As described above, the toilet paper roll of the present invention is easy to manufacture even in a long size, has no wrinkles, creases, etc., can recognize a pattern with excellent design, and can easily feel the smoothness of the surface.

1: Toilet paper roll 10,34:Toilet paper 20: Paper tube (tube core) L1: Width of toilet paper roll L2: Roll diameter of toilet paper roll L3: outer diameter of paper tube 31,35:White board paper 32: Pattern part 33:Sample 36:Window opening part 40:Lower pattern 41: The first solid part of the upper level 42: The second field part of the upper level 51: concave part 53: Valley Line Department

FIG. 1 is a perspective view of a toilet paper roll according to an embodiment of the present invention. FIG. 2 is a schematic diagram for explaining the measurement procedure of whiteness and color difference according to the present invention. FIG. 3 is a diagram for explaining pattern printing according to the present invention. FIG. 4 is a diagram for explaining an example of an embossing pattern according to the present invention.

Domestic storage information (please note in order of storage institution, date and number) without Overseas storage information (please note in order of storage country, institution, date, and number) without

1: Toilet paper roll

10:Toilet paper

20: Paper tube (tube core)

L1: Width of toilet paper roll

L2: Roll diameter of toilet paper roll

L3: outer diameter of paper tube

Claims (7)

A kind of toilet paper roll, which is made by rolling double-layer toilet paper into a roll toilet paper with a roll diameter of 90~120mm. It is characterized in that: the basis weight of a single layer of the aforementioned toilet paper is 11.0~14.0g/ ^m2 , and the paper thickness is 60~90μm, and has unevenness produced by embossing, and has a pattern formed by solid printing on one of the surfaces. The pattern has a first solid portion and a second solid portion of different colors. The pattern The proportion of the above-mentioned first solid part to the total area is 8~20%, the proportion of the aforementioned first solid part to the total area is 2.0~4.0%, the proportion of the aforementioned second solid part to the total area is more than 6.0%, and the toilet paper of the roll toilet paper The paper tube is wound with a length of 65 to 90 m and a winding density of 0.83 to 2.05 so that the surface printed with the aforementioned pattern becomes the outer layer side. The toilet paper roll according to claim 1, wherein the ten-point average roughness [RzJIS] of the outer layer side of the toilet paper is 0.025mm~0.320mm. The toilet paper roll according to claim 1, wherein the toilet paper is two sheets in which a recess is formed on one surface and a convex part is formed on the other surface by embossing. Double-layered double-embossed toilet paper is a double-layered toilet paper laminated so that the concave portion-forming surface of the sheet faces outward. The roll of toilet paper according to claim 2, wherein the toilet paper is two sheets in which a recess is formed on one surface and a convex part is formed on the other surface by embossing. Double-layered double-embossed toilet paper is a double-layered toilet paper laminated so that the concave portion-forming surface of the sheet faces outward. The roll toilet paper according to any one of claims 1 to 4, wherein the roll density is 0.1~0.3g/cm ³ . The toilet paper roll according to any one of claims 1 to 4, wherein the void ratio is 3 to 20%. The toilet paper roll according to claim 5, wherein the void ratio is 3 to 20%.

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