JP6701550B2 - Rolled paper towel - Google Patents

Description

  The present invention relates to a paper towel roll body having an increased roll length.

  Paper towels are widely used in kitchens of homes, kitchens of restaurants, etc. for purposes such as wiping off water and oil and removing dirt (see, for example, Patent Document 1). Here, when the paper towel is used frequently, the paper towel is frequently replaced with the paper towel holder, which may be troublesome for the user. In order to reduce the frequency of changing the paper towel, it is conceivable to increase the winding length per roll.

JP, 2010-068972, A

  However, by increasing the winding length, it is known that the texture and water absorption of the paper towel are reduced, and that wrinkles, roll deformation, and the like in the processing step occur, and in the conventional technique, an increase in the winding length, It was difficult to maintain the texture and water absorption of the paper towel and prevent wrinkles and roll deformation. Therefore, an object of the present invention is to provide a paper towel roll body having an increased winding length, in which the texture and the water absorption amount are favorably maintained, and a wrinkle or roll deformation does not occur. ..

  The inventors of the present invention have conducted diligent research in view of the above problems. As a result, a paper towel obtained by adding a dry paper-strengthening agent and a wet paper-strengthening agent to beating-treated pulp fibers and stacking two single sheets obtained by papermaking was used at a predetermined winding density and winding hardness of 20 m. By finding that the above problems can be solved by winding 40 m or less, the present invention has been completed. Specifically, the present invention provides the following.

(1) In the first aspect of the present invention, a paper towel in which two single sheets having a grammage of 19.0 g/m ² or more and 25.0 g/m ² or less are laminated has a winding density of 0.50 m/cm ^2. It is a roll of paper towel wound with a winding hardness of 0.80 m/cm ² or less and a winding hardness of less than 10 mm and 20 m or more and 40 m or less.

(2) A second aspect of the present invention is the roll of the paper towel according to (1), wherein the water absorption TWA of the paper towel is 170 g/m ² or more and 220 g/m ² or less. It is a thing.

  (3) A third aspect of the present invention is the roll of paper towel according to (1) or (2), wherein the paper towel has a longitudinal tensile strength DMD when dried and a lateral tensile strength when dried. The geometric mean GMT of DCD is 11.0 N/25 mm or more and 22.0 N/25 mm or less.

  (4) A fourth aspect of the present invention is the roll of the paper towel according to any one of (1) to (3), which has a winding hardness of 4 mm or more and 8 mm or less. is there.

  (5) A fifth aspect of the present invention is the roll of the paper towel according to any one of (1) to (4), in which one surface of a paper towel having two single sheets laminated has an embossed convex portion. And an embossed recess formed on the other surface by the back surface of the embossed projection.

(6) A sixth aspect of the present invention is the roll of the paper towel according to (5), wherein the embossing area ratio of embossing forming the embossed protrusions and the embossed recesses is 10% or more and 25% or less. The embossed edge ratio is 0.3 mm/mm ² or more and 0.6 mm/mm ² or less.

  The roll of the paper towel of the present invention is a paper towel obtained by adding a dry paper-strengthening agent and a wet paper-strengthening agent to beating pulp fibers, and laminating a single sheet obtained by papermaking to a predetermined roll density and a predetermined roll density. Since it is wound with a winding hardness, even if the winding length is increased, the texture and the water absorption amount are kept good, and winding wrinkles and roll deformation do not occur.

It is drawing which shows the embossed shape of the paper towel of this invention. It is drawing which shows the measuring apparatus of the winding hardness of the roll body of a paper towel.

Hereinafter, the present invention will be described in detail with reference to the drawings.
<Paper towel rolls>
The roll of a paper towel of the present invention is a paper towel obtained by laminating two single sheets having a predetermined basis weight and wound at a predetermined winding density and a predetermined winding hardness over 20 m or more and 40 m or less. ..

[Single sheet]
The single sheet used for the paper towel is made by beating pulp fibers with a refiner or the like to make paper. By beating the raw pulp fiber, the pulp fiber becomes fluffy, the texture of the paper towel becomes good, and the strength of the single sheet can be improved. However, since the paper thickness of a single sheet is reduced and the water absorption is also reduced by only beating, strength and water absorption can be improved by internally adding a dry paper strength enhancer and a wet paper strength enhancer during papermaking. And can be improved together. As a result, the basis weight of a single sheet measured according to JIS P 8124 can be within the range of 19 g/m ² or more and 25 g/m ² or less.

(Pulp fiber)
Pulp fibers are typically wood pulp fibers produced from conifers or hardwoods. For example, bleached and refined pulp fibers are bleached and processed bleached softwood kraft pulp fibers (NBKP) and bleached hardwood kraft pulp fibers ( LBKP), and mixtures thereof can be used. Among these, the paper strength and the water absorption can be further improved by adding a higher content of the bleached softwood kraft pulp fiber.

  In addition, in the preparation of the single sheet, in addition to the wood pulp fiber, other fibers can be appropriately blended within a range not impairing the object of the present invention. Examples of such other fibers include mechanical pulp fibers such as ground wood pulp fibers (GP); chemical pulp fibers such as sulfite pulp fibers; semi-chemical pulp fibers obtained by combining chemical treatment and mechanical treatment; kenaf , Non-wood pulp fibers such as cotton linter and hemp; waste paper pulp fibers and the like.

(Dry paper strength enhancer and wet paper strength enhancer)
Examples of the dry paper strengthening agent that can be used in the present invention include cationized starch, polyacrylamide, and carboxymethyl cellulose. Of these, cationized starch is preferably used. Further, examples of the wet paper strengthening agent usable in the present invention include polyamide epichlorohydrin resin and melamine resin. The addition amount of the dry strength agent and the wet strength agent is preferably 1.0 part by mass or more and 5.0 parts by mass or less per 100 parts by mass of pulp fiber.

(Crepe rate)
In the present invention, it is preferable that the crepe ratio at the time of drying the single sheet made from paper is 20% or more. By setting the crepe ratio to 20% or more, the strength and water absorption of a single sheet can be improved. The crepe rate (%) is calculated by {(dryer speed)-(reel speed)}/(dryer speed)×100. Here, the reel speed means a winding speed on a roll.

[Paper towel]
The paper towel constituting the roll of the paper towel of the present invention is a laminate of the two single sheets described above. One surface of the paper towel has an embossed convex portion, and the other surface has the embossed convex portion. It has an embossed recess formed on the back surface.

(Embossing)
When embossing a paper towel, first, emboss the single sheet, and then form the embossed protrusions on one surface of the single sheet and the embossed depressions on the opposite side that are the back side of the embossed protrusions. To do. The embossing can be performed by a known method. For example, the male (convex) embossing roll and the female (concave) embossing roll having substantially complementary shapes may be processed by a “matched” embossing roll, The male (convex) embossing roll and the female (concave) embossing roll do not have the same shape, and may be processed by a so-called "non-matching" embossing roll that gives a shearing force to the sheet when they mesh with each other.

The embossed area ratio of the embossed protrusions in each single sheet is preferably 10% or more and 25% or less , and more preferably 14% or more and 20% or less. By setting the embossed area ratio within the above range, the water absorption and the strength of the paper towel are balanced. The above-mentioned embossed area ratio of the embossed convex portion is obtained by measuring the area of the embossed portion formed on the sheet (Sn=a×b×n in FIG. 1, where n is the total number of embossed patterns), and the area ratio ( It can be calculated as Sn/(A×B)).

The embossed edge ratio of each single sheet is preferably 0.3 mm/mm ² or more and 0.6 mm/mm ² or less, and 0.4 mm/mm ² or more and 0.5 mm/mm ² or less. More preferable. By setting the embossed edge ratio within the above range, the water absorption and the strength of the paper towel are balanced. The above-mentioned embossed edge ratio is obtained by summing up each side of the embossed convex portion per unit area, and referring to FIG. 1, it is calculated by (a×2+b×2)×n/(A×B). It

(Single sheet lamination)
The two embossed single sheets become a paper towel by gluing the embossed convex portion of one single sheet onto a predetermined portion of the other single sheet. In the present invention, the embossing pattern of the paper towel is preferably a so-called nested embossing in which the embossed convex portion of one single sheet is glued in a state of entering into the embossed concave portion of the other single sheet. By using the nested embossing, a space is maintained between the two single sheets, and the water absorption and bulkiness of the paper towel can be improved.

  In the present invention, it is preferable that the density of the glue used for gluing each single sheet to be higher than that of the conventional one (for example, 1.5 times or more), so that the strength of the paper towel (particularly GMT) can be obtained. ) Is known to improve. The glue used for gluing is not particularly limited, and examples thereof include polyvinyl alcohol and starch-based glue.

(Water absorption)
The paper towel obtained from the roll of the paper towel of the present invention is obtained by making beating pulp fibers into paper, and is wound at a predetermined winding density and winding hardness, so that it has good water absorption. Have sex. The water absorbency (TWA: Total Water Absorbency) of the paper towel is preferably 170 g/m ² or more and 220 g/m ² or less, and more preferably 180 g/m ² or more and 200 g/m ² or less. Such water absorption of the paper towel has not been realized in the past with a roll of paper towel having a roll length of more than 20 m, but when the configuration of the present invention is adopted, the roll length of the paper towel is more than 20 m. A roll of paper towel having water absorbency as described above can be realized.

The water absorption can be obtained according to the following measuring method. First, a paper towel is cut into a square of 76 mm×76 mm to prepare a sample, and its dry weight is measured. Next, after dipping this sample in distilled water for 2 minutes, one corner of the sample was made to be the top of the upper side in a container saturated with water vapor (RH 100%), and two corners adjacent to this top were placed. It is hung in a stretched state while supporting the part and left for 30 minutes, and the weight after draining is measured. Then, the measured value is converted into water absorption (g/m ² ) per 1 m ² of the sample.

(Tensile strength)
The paper towel to which the present invention is applied is based on JIS P 8113 (test method for tensile properties of paper and paperboard), and has a longitudinal tensile strength (DMD; Dry Machine Direction) when measured on a test piece having a width of 25 mm. The geometric mean GMT (Geometric Mean Tensile strength) of tensile strength (TDD) and transverse tensile strength (DCD; Dry Cross Direction strength) is preferably 11.0 N/25 mm or more and more preferably 22.0 N/25 mm or less. It becomes 12.0 N/25 mm or more and 20.0 N/25 mm or less. By setting the GMT within the above range, the paper towel has an appropriate degree of practically suitable resistance to tearing and also has sufficient softness.

[Paper towel rolls]
The paper towel described above becomes a roll of paper towel by winding 20 m or more and 40 m or less around the core. At this time, by setting the speed of the roll winder to 150 m/min or more and 200 m/min, stable winding without wrinkles can be performed. The core is not particularly limited, and any core such as a paper core can be used. The roll body of the long width paper towel wound around the winding core is cut into a predetermined width by a log saw.

(Winding density)
Roll of the paper towels of the present invention, the winding density of 0.50 m / cm ² or more 0.80 m / cm ² or less. The winding density is influenced by the paper quality of the paper towel, and can be adjusted by the tension of the roll winder and the nip pressure of the embossing roll in the winding process. By setting the winding density as described above, it is possible to prevent the occurrence of winding wrinkles and roll deformation even with a roll of paper towel having a winding length of more than 20 m.

  Here, the winding density can be calculated by (winding length×number of single sheets)/(roll cross-sectional area). In obtaining the roll cross-sectional area of the roll body of the paper towel, the cross-sectional area of the core portion may be subtracted from the cross-sectional area of the outer diameter portion of the roll body.

(Rolling hardness)
The roll of the paper towel of the present invention has a winding hardness of less than 10 mm, preferably 4 mm or more and 8 mm or less. The winding hardness is affected by the paper quality of the paper towel, and can be adjusted by the tension of the roll winder and the nip pressure of the embossing roll in the winding process. By setting the winding hardness as described above, it is possible to prevent the occurrence of wrinkles and roll deformation even with a roll of paper towel having a roll length of more than 20 m.

The roll hardness can be defined as the amount of deformation of the roll of the paper towel of the present invention when a load of 625 g is applied to the roll of the paper towel, and the roll hardness is measured by the measuring device shown in FIG. It is measured using 10. The measuring device 10 includes a base portion 2, support rods 4a and 4b, a movable weight mounting plate 6, and a weight 8 of 625g. The two support rods 4a and 4b stand upright from the base portion 2, and the rectangular movable weight placing plate 6 is provided at both ends with through holes for the support rods 4a and 4b. Then, the roll body 20 of the paper towel is placed on the base portion 2 between the support rods 4a and 4b, and the support rods 4a and 4b are inserted from above the roll body 20 of the paper towel into the movable weight placing plate 6. The movable weight placing plate 6 is placed on the upper surface of the roll body 20. The height of the movable weight mounting plate 6 in this state is referred to as an initial height h ₁ . When the weight 8 is further placed on the movable weight placing plate 6, the moving weight placing plate 6 slides through the support rods 4a and 4b by the weight of the weight 8 while deforming the roll body 20 and sinking. the height _{h 2} is _measured, and obtains the _(h 2 -h ₁₎ as the amount of deformation of the diameter of the roll body.

  Perforations may be formed in the paper towel forming the roll body of the paper towel along the axial direction of the roll body. In this case, if the perforation cutting strength is set to 11.8 N/100 mm or more and 21.6 N/100 mm or less, it becomes easy to take out the paper towel. In order to adjust the cutting strength of perforations, it is sufficient to adjust the cutting interval of the perforations (cutting width of perforations). The perforation cutting strength is obtained by performing a tensile test so that the perforation of the paper towel is located in the center between the two grips of the tensile tester, measuring the cutting strength, and converting it into a value of 100 mm width. Good.

  Hereinafter, the present invention will be described in detail with reference to examples. The present invention is not limited to the examples shown below.

<Examples 1 to 3 and Comparative Example 1>
A mixture of softwood bleached kraft pulp fiber (NBKP) and hardwood bleached kraft pulp fiber (LBKP) was beaten with a refiner, and 1.6 parts by mass of a dry paper strengthening agent (cationized starch) per 100 parts by mass of pulp fiber. Then, 3.7 parts by mass of a wet paper strength enhancer (polyamide epichlorohydrin resin) was added, and a single sheet having a basis weight shown in Table 1 was produced by a tissue paper machine. Next, this single sheet was embossed with an embossing machine to obtain an embossed area ratio of 14.0% or 12.0% and an embossed edge ratio of 0.42 mm/mm ² or 0.53 mm/mm ² . The embossed convex portion was formed so that

A state in which water-soluble glue (polyvinyl alcohol) is applied to the embossed protrusions of one single sheet among the embossed single sheets, and the embossed protrusions enter the embossed recesses of another single sheet ( It was glued with (nested emboss). The paper towel thus obtained was wound around a winding core so as to have a predetermined winding length, winding density, and winding hardness to obtain a roll of paper towel having a width of 206 mm. The paper towel was perforated with a predetermined cutting strength in the width direction, and the tie cut ratio of the perforations was 1:10 (bond:cut width). The results are shown in Table 1.

<Evaluation>
[thickness]
The thickness of the paper towel was measured using a thickness gauge (manufactured by Ozaki Seisakusho, dial thickness gauge "PEACOCK"). A sample (10 paper towels) was placed between the tracing stylus and the measuring stand with a measuring load of 3.7 kPa and a tracing stylus diameter of 30 mm, and the gauge was read when the tracing stylus was lowered at a speed of 1 mm or less per second. The measurement was repeated 10 times, and the numerical values obtained were averaged.

[Tab strength]
The tab strength of the paper towel was measured using a Tensilon universal testing machine. The measurement procedure was as follows. After removing the sheets up to the middle winding of the roll, 9 consecutive sheets are taken from the roll, and a 3 inch mold blade is used so that the tabs can be taken in 6 consecutive locations (2 sheets + 2 sheets + 2 sheets + 1 sheet removal + 2 sheets + 2 sheets + 2 sheets). Punched out with. The prepared sample was set in a Tensilon universal testing machine, pulled at a speed of 200 mm/min, and the tensile strength was measured until it broke from the perforation. It measured 6 times and calculated the average value.

As can be seen from Table 1, in the rolls of the paper towel of the example in which the winding hardness was less than 10 mm, the water absorbency of the paper towel was good, and the strength was also suitably maintained. Further, the paper towel embodiments, 10 mm or more winding hardness, correspond to 0.5 m / cm ² or more 0.80 m / cm ² or less in the winding density, while the wrinkles or roll deformation did not occur around the roll body Then, it was confirmed that in the paper towel of the comparative example, the roll body had wrinkles and roll deformation. Since the roll of paper towel is less likely to be deformed, it is easy to load when changing to a paper towel holder.

10 Measuring device 2 Base part 20 Roll body 4a, 4b Support rod 6 Moving weight support plate 8 Weight

Claims (6)

Paper towel basis weight was laminated two sheets of single sheet is 19.0 g / ^{m 2} or more 25.0 g / ^{m 2} or less, winding density 0.50 m / cm ² or more 0.80 m / cm ² or less, the winding hardness 20 m or more and 40 m or less are wound with less than 10 mm ,
The water absorption TWA of the paper towel is 170 g/m ² or more and 220 g/m ² or less,
The geometric mean GMT of the dry tensile strength DMD and the dry tensile strength DCD of the paper towel is 12.0 N/25 mm or more and 22.0 N/25 mm or less.
A roll of paper towels. The roll body of the paper towel according to claim 1 , which has a winding hardness of 4 mm or more and 8 mm or less. The paper towel according to claim 1 or 2 , wherein one surface of a paper towel in which two single sheets are laminated has an embossed convex portion, and the other surface has an embossed concave portion formed by the back surface of the embossed convex portion. Roll body. The embossing convex portion and the embossed area ratio of embossing to form the embossed depressions 25% 10% or more or less, embossed edge rate is 0.3 mm / mm ² or more 0.6 mm / mm ² or less, to claim 3 Rolled paper towel described. The embossed convex portion of one of the single sheets is glued in a state of entering the embossed concave portion of the other single sheet,
The roll body of the paper towel according to claim 3 or 4. The single sheet is obtained by adding a dry paper strength enhancer and a wet paper strength enhancer to beating pulp fibers, and making a paper.
The roll body of the paper towel according to any one of claims 1 to 5.

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