JP2011226018A - Base paper for paper shaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a base paper for a paper shaft which has improved rigidity as the paper shaft and excellent suitability for the paper shaft processing and is free from peeling or wrinkle due to adhesion failure.SOLUTION: A base paper for paper axis satisfies following conditions 1.-6.: 1. Used as a base pulp are NBKP (needle-leaf tree bleached kraft pulp) and LBKP (broadleaf tree bleached kraft pulp). The mass ratio of NBKP to LBKP is 20:80-80:20. 2. The beating is performed such that the Canadian standard freeness of the NBKP is 400-650 mlCSF and the Canadian standard freeness of the LBKP is 400-500 mlCSF. 3. The basis weight lies within the range of 30-70 g/m. 4. The degree of Steckigt sizing is 5 sec or more. 5. The paper shaft is wound in a CD-direction (MD-direction is axis) and the aspect ratio (length÷width) of tensile strength lies within the range of 1.4-2.4. 6. The aspect ratio (length÷width) of Clark rigidity lies within the range of 1.5-2.3.

Description

The present invention relates to a base paper for a paper shaft used for a cotton swab, an earpick, a stirring stick and the like.

In addition to wooden and plastic shafts, paper shafts are used as shafts for cotton swabs, earpicks, and stirring sticks. Wooden is difficult in terms of mass production and cost, and plastic is advantageous in these respects, but it uses petroleum as a raw material and has a problem in terms of resource saving. Paper materials are made of wood and are considered to be environmentally friendly materials because they are planted and are easy to recycle after use.
The paper shaft is manufactured by applying an adhesive to a paper sheet cut into a predetermined rectangle and winding it. Since the paper shaft is more flexible than the wooden or plastic shaft, depending on the application, the rigidity of the paper shaft may be insufficient, causing problems as a product. For example, if the shaft has insufficient rigidity with a cotton swab, there arises a problem that the wiping property is inferior. In addition, as described above, the paper shaft is manufactured by applying an adhesive to a paper sheet cut into a rectangular shape and winding it, so depending on the paper quality of the base paper, it may be jammed due to curling, or it may be clogged or wrinkled due to poor adhesion. Troubles peculiar to paper shaft manufacturing may occur.

In order to improve the rigidity of the paper shaft, it is conceivable to increase the basis weight of the base paper or increase the number of windings, but the amount of base paper used will increase and the shaft diameter may exceed the required standard. is there.
The paper shaft can be made by mixing synthetic fiber with pulp, or by applying or impregnating synthetic resin, or by laminating a synthetic resin film. This is not desirable in terms of resource saving.
Therefore, there is a demand for paper shaft base paper that is manufactured only from paper material and has improved rigidity.
The idea of Patent Document 1 is a paper shaft characterized in that the axial direction coincides with the direction of the fiber of the paper, and more effectively uses resources by using recycled paper made from waste milk cartons as raw materials. And increasing the strength of the paper shaft. However, there is no detailed examination on the fiber orientation of paper and the rigidity of paper.
Patent Document 2 describes that the strength is increased by mixing synthetic fibers to make paper, applying or impregnating a synthetic resin, laminating a synthetic resin film, and the like. However, as described above, the use of synthetic fibers or synthetic resins is not desirable in terms of resource saving.
In Patent Document 3, silicon oxide is applied to the surface of the paper shaft and solidified to impart water resistance and heat water resistance. However, these processes have a problem that the paper shaft manufacturing process increases.

Japanese Utility Model Publication No. 7-3481 JP 2003-79505 A JP 2006-68307 A

SUMMARY OF THE INVENTION In view of the above-described circumstances, the present invention aims to provide a paper base paper for paper shaft that has improved rigidity when used as a paper shaft and has good suitability for paper shaft processing without generation of creaking or wrinkle due to poor adhesion. There is to do.

In order to solve the above-described problems, the paper shaft base paper of the present invention has the following characteristics.
The paper shaft base paper of the first invention is
A base paper for a paper shaft formed by winding and adhering sheet-like paper, characterized by satisfying the following conditions.
(1) NBKP (softwood bleached kraft pulp) and LBKP (hardwood bleached kraft pulp) are used as raw material pulp, and the mass ratio of NBKP to LBKP is 20:80 to 80:20.
(2) The Canadian standard freeness of NBKP is beaten to 400 to 650 ml CSF, and the Canadian standard freeness of LBKP is beaten to 400 to 500 ml CSF.
(3) Basis weight is in the range of 30 to 70 g / m ² .
(4) The Steecht sizing degree is 5 seconds or more.
(5) The paper axis is wound in the CD direction (MD direction is the axis), and the aspect ratio (vertical / horizontal) of the tensile strength is in the range of 1.4 to 2.4.
(6) Clark stiffness has an aspect ratio (vertical / horizontal) in the range of 1.5 to 2.3.
The paper shaft base paper of the second invention is
2. The paper shaft according to claim 1, wherein the base paper is single glossy paper, and a paper strength enhancer is spray-applied to the wet paper in the manufacturing process so that the density is 0.70 g / cm ³ or more. Base paper. It is.

According to the paper shaft base paper of the present invention, the paper shaft base paper is formed by winding and adhering sheet-like paper, and (1) NBKP (conifer bleached kraft pulp) and LBKP are used as raw pulp. (Hardwood bleached kraft pulp) is used, and the mass ratio of NBKP to LBKP is 20:80 to 80:20. (2) The Canadian standard freeness of NBKP is beaten to 400 to 650 ml CSF, and the Canadian standard freeness of LBKP is beaten to 400 to 500 ml CSF. (3) Basis weight is in the range of 30 to 70 g / m ² . (4) The Steecht sizing degree is 5 seconds or more. (5) The paper axis is wound in the CD direction (MD direction is the axis), and the aspect ratio (vertical / horizontal) of the tensile strength is in the range of 1.4 to 2.4. (6) Clark stiffness has an aspect ratio (vertical / horizontal) in the range of 1.5 to 2.3. By taking the configuration
It is possible to provide a paper base paper having improved rigidity and good workability.
Further, the base paper is single glossy paper, and a paper strength enhancer is spray-coated on the wet paper in the manufacturing process so that the density is 0.70 g / cm ³ or more. A base paper can be provided.

Embodiments of the present invention will be described below.
First, paper shaft processing will be described.
In the paper shaft processing, a base paper cut into a predetermined size is loosely rounded, wound with a roll while being glued, turned into a shaft, and then dried. Since the paper stock for paper shaft is cut and supplied to the paper shaft processing machine, if the curl tendency is strong, troubles of paper jam may occur. Before supplying to the paper shaft processing machine, apply steam to the base paper, The curl may be corrected.
In addition, depending on the quality of the base paper, defects such as creaking or wrinkling may occur on the manufactured paper shaft. Meklet is a phenomenon in which the edge of the adhered paper is peeled off, the appearance is deteriorated, and the shaft strength is reduced. Wrinkles occur when gluing and winding. For example, in the manufacture of cotton swabs, cotton is applied to the paper shaft while the paper shaft is rolled with the paper shaft sandwiched between the belts. This may occur if the paper axis is not uniform.
The diameter of the paper shaft is set in consideration of required strength and ease of use at the time of use, and is usually about 1.0 to 3.0 mm. The length of the paper shaft is set to a length that is easy to use, and is usually about 50 to 160 mm. The number of entrainment is about 10 to 40 times.

Next, the paper shaft base paper according to the present invention will be described.
The base paper for paper shaft according to the present invention uses NBKP (softwood bleached kraft pulp) and LBKP (hardwood bleached kraft pulp) as raw pulp, and the mass ratio thereof is 20:80 to 80:20. Preferably, the Canadian standard freeness of NBKP is 400 to 650 ml CSF, and the Canadian standard freeness of LBKP is 400 to 500 ml CSF.
By setting it within this range, the strength of the paper shaft can be increased, and since the texture is good, there is no problem of wrinkling during paper shaft processing. If NBKP is more than this range, the texture becomes poor and the paper shaft processing aptitude is deteriorated. If NBKP is less than this range, the paper shaft strength is insufficient. The basis weight of the paper shaft base paper is set according to the diameter of the paper shaft, and if it is 30 to 70 g / m ² , the paper shaft processing is easy and desirable. If the basis weight is less than 30 g / m ^2, may stretch the paper by application of the adhesive during the paper-axis machining is increased wrinkles, high rigidity of the paper is more than 70 g / m ² Too much wrinkling and poor adhesion may occur during winding of the paper shaft processing.

As the chemical internally added to the raw material pulp in the present invention, a size fixing agent, a sizing agent, a paper strength enhancer and the like can be used. As the size fixing agent, a sulfuric acid band, cationic starch, polyacrylamide resin or the like can be used. As the sizing agent, a sizing agent such as a saponified rosin sizing agent, a rosin emulsion sizing agent, an alkyl ketene dimer, or an alkenyl succinic anhydride can be used. As the paper strength enhancer, cationic starch, polyacrylamide resin and the like can be used. In addition, additives such as a wet paper strength enhancer, a slime control agent, a pitch control agent, an antifoaming agent, and a dye can be used as necessary.

In the paper shaft base paper manufacturing method of the present invention, at least a wire part for dewatering the stock, a press part for squeezing the dehydrated wet paper, and a dryer part for drying the squeezed wet paper are provided in a row. Use a paper machine.
Since the base paper of the present invention is used for a paper shaft, the fiber orientation is different from that of general paper such as printing paper, newsprint, and copy paper.
That is, the above-described general paper disperses fibers as uniformly as possible from the viewpoints of appearance, texture, printability, curl, and the like. However, the paper shaft base paper of the present invention is adjusted so that the fibers are aligned in the MD direction within a certain range, thereby imparting strength and processability as a paper shaft.

Specifically, the tensile strength aspect ratio is preferably 1.4 to 2.4. By setting the aspect ratio of the tensile strength to 1.4 to 2.4, the fiber orientation can be made suitable for the paper shaft base paper. That is, the aspect ratio of Clark stiffness can be in the range of 1.5 to 2.3. When the aspect ratio of the Clark stiffness is less than 1.5, it is necessary to take measures such as increasing the basis weight in order to increase the paper shaft strength. If it exceeds 2.3, it is difficult to adjust the orientation of the pulp fiber on the paper machine, and the productivity of the paper base paper may be lowered, and wrinkles may occur during paper shaft processing. The tensile strength aspect ratio can be adjusted by the ratio of the speed (J) of the raw material ejected from the paper machine inlet to the wire speed (W) of the paper machine, that is, the jet wire ratio (J / W ratio). it can. In addition, it varies depending on the freeness of the raw material, the raw material concentration, the foil arrangement, the presence or absence of wire shaking, etc. related to the dewatered state of the wire.
By configuring as described above, the aspect ratio (vertical / horizontal) of the Clark stiffness is in the range of 1.5 to 2.3. By doing so, the axial strength of the paper shaft can be increased.
Clark stiffness (vertical) is a value directly affects the axial strength of the paper shaft, but its value is preferably larger, it is desirable in the case of basis weight 60 g / m ² is 50 cm ^3/100 or more. At this time, considering that the raw material is uniform and the Clark stiffness is proportional to the square of the basis weight, it is desirable that the Clark stiffness index expressed by the following (Equation 1) is 1.4 or more.
(Equation 1) Clark stiffness index = Clark stiffness ^[cm 3/100] / (basis weight ^{[g / m 2]) 2} × 100
According to this, for example, in the paper-axis base paper having a basis weight of 40 g / ^{m 2,} it is desirable Clark stiffness (vertical) is 22 cm ^3/100 or more.

By the way, there are generally two winding directions when manufacturing the paper shaft, and there are CD direction winding (winding with the MD direction as the axis) and MD direction winding (winding with the CD direction as the axis). (Here, the CD direction refers to the horizontal direction of the paper, and the MD direction refers to the vertical direction of the paper.)
The paper shaft base paper of the present invention relates to a paper shaft used for winding in the CD direction.

The paper base for the paper shaft of the present invention is desirably single-gloss paper, and in the manufacturing process, a surface treatment agent containing a paper strength enhancer is spray-coated on the wet paper so that the density is 0.70 g / cm ³ or more. It is desirable. By doing in this way, the paper shaft base paper having higher shaft strength and good workability can be obtained.
That is, the spray application of the paper strength enhancer increases the density of the base paper for the paper shaft and increases the shaft strength, and also improves adhesion to the Yankee dryer and prevents curling. Occasionally paper jams will not occur.
As described above, the paper shaft base paper of the present invention is adjusted so that the fibers are aligned in the MD direction in order to obtain the shaft strength. Therefore, the expansion and contraction in the CD direction due to moisture absorption and release is large, and curling is likely to occur. Tend. Therefore, it is desirable to perform spray coating of a paper strength enhancer for the purpose of preventing curling.

When performing spray coating, a spray device is installed in the paper machine, and a surface treatment agent containing a paper strength enhancer is sprayed on the front side of the wet paper. And at the same time or immediately after the spray application of the surface treatment agent containing the paper strength enhancer, it is possible to suck and dehydrate in the direction from the front side to the back side of the wet paper, and to allow the sprayed surface treatment agent to penetrate into the paper layer. preferable. Note that the front side of the wet paper refers to the surface that becomes the glossy surface of the glossy paper in contact with the Yankee dryer, and the back surface of the wet paper refers to the surface that becomes the anti-glossy surface of the glossy paper.

In spray coating, it is necessary to optimize the shape and arrangement of the spray nozzle, the coating concentration, and the coating amount in order to reduce coating unevenness, but the front surface is changed from the front surface to the back surface at the same time or immediately after spraying. By performing suction dehydration, the surface treatment agent is appropriately dispersed in the paper layer, so that the optimization described above is easy and the effect of the surface treatment agent is sufficiently exhibited.

The roll used for the press part of the paper machine is a plain roll with a flat surface, and a grooved roll with a groove with a width of 0.2 to 0.5 mm, a depth of 2 to 3 mm, and a pitch of about 3 mm on the rubber-coated surface. There is a suction roll (including a suction grooved roll in which a groove is provided in the suction roll) that sucks water at the same time as squeezing by providing a suction part inside the roll. Usually, a pair of nip portions in which these rolls are combined are installed in a plurality of stages to form a press part. In the present invention, it is necessary to spray the surface treatment agent on the front surface and perform suction dehydration in the direction from the front surface to the back surface at the same time or immediately after the spraying, and the surface treatment agent is spray-coated on the wet paper at such a position. .

A press part of a paper machine for producing single gloss paper usually has three to four pairs of nip portions by the rolls described above. The position of the spray may be any place where the spray device can be installed, but the upstream position is preferable, and in this way, the wet paper after the surface treatment agent spray passes through more nips. Therefore, the surface treatment agent can be uniformly dispersed in the paper layer.

As the paper strength enhancer to be sprayed, corn, tapioca, potato, wheat, rice starch, modified starch such as oxidized starch, cationic starch, polyacrylamide resin, polyvinyl alcohol, styrene butadiene copolymer latex, etc. are used. However, it is preferable to use cationic starch in view of the effect of improving the fixability of the chemical and the axial strength. Further, a dryer remover, a dryer adhesive, a viscosity modifier, a preservative, and the like may be added to the surface treatment agent.

The wet paper moisture when spraying the surface treatment agent is preferably 60 to 90%. If it is lower than 60%, the dispersion of the spray-treated surface treatment agent in the paper layer becomes insufficient, and if it is higher than 90%, there is a problem that the surface treatment agent is washed away during squeezing in the press part.

In the present invention, a surface treatment agent is spray-coated on a wet paper having a high moisture content, and suction dehydration is performed simultaneously with or immediately after the application, so that the surface treatment agent penetrates into the paper layer and is made uniform. A suction box or a suction roll can be used as a suction device for performing suction dehydration.
The coating amount of the surface treatment agent is preferably 0.30 to 2.0 g / m ² in terms of solid content. The coating amount of the surface treatment agent is preferably 30 to 200 g / m ² in solid form, and more preferably 70 to 100 g / m ² . By setting it in such a range, the effect of the surface treatment agent is optimized.

The coating concentration of the surface treatment agent is preferably 0.50 to 2.0% by mass. When the coating concentration of the surface treatment agent is lower than 0.50% by mass, it is difficult to obtain a coating amount sufficient to obtain a chemical effect. If the coating concentration of the surface treatment agent is higher than 2.0% by mass, it will be difficult to make the surface treatment agent uniform by suction dehydration, and the wet paper and the Yankee dryer will become too strong when dried with a Yankee dryer. It is easy for fluffing to occur.

As the spray method, either one fluid spray or gas-liquid two fluid spray can be used. The spray pattern can be fan-shaped, full cone, or empty cone. Adjust the installation interval and number of spray nozzles so that there is no uneven coating.

In the paper shaft base paper manufacturing method of the present invention, after drying with a dryer, smoothing and paper thickness can be made uniform with a calendar device. As such a calendar device, commonly used calendar devices such as a chilled calendar, a super calendar, a soft calendar, and a gloss calendar can be used.

The paper shaft base paper of the present invention obtained by the above-described production method is JAPAN TAPPI No. The wax pick according to No. 1 is 10A or more on both the front and back surfaces.
It is desirable that the sizing degree by JISP8122 is 5 seconds or more.
If the Steecht sizing degree is less than 5 seconds, the penetration of the adhesive may be too fast, resulting in mekre due to poor adhesion.
Further, the density is 0.70 g / cm ³ or more. By doing so, it is possible to prevent wrinkling during paper shaft processing.

Hereinafter, the effects of the present invention will be specifically described by Examples and Comparative Examples. In addition, unless otherwise indicated,% represents the mass% in conversion of solid content, and the addition amount is represented with the quantity with respect to 100 mass parts of absolutely dry pulp.

Example 1
Raw material pulp consisting of NBKP 45 parts by mass (freeness 650 ml CSF) and LBKP 55 parts by mass (freeness 460 ml CSF) is used. Sulfuric acid band 2.5 mass% (alumina conversion concentration 8% product: solid), acidic rosin sizing agent (Product name: AL1206, manufactured by Seiko PMC Co., Ltd.) 0.5 mass%, polyacrylamide type paper strength enhancer (Product name: DS4789, manufactured by Seiko PMC Co., Ltd.) 0.25 mass%, cationic starch (GS L Japan) Product name: Geltron 24) 0.5% by mass was added to make paper. In the press part after passing through the wire part, cationic starch (trade name: CATO304, manufactured by NSC Japan Co., Ltd.) is adjusted to 0.60% as a paper strength enhancer on the wet paper front side, and the coating amount is 0.60 g / m ² was sprayed so that (Yusugata 100 g / ^{m 2),} was produced base paper for paper axis having a basis weight of 60 g / ^{m 2.} In the first press immediately after spraying, the front side of the paper is in contact with the plain roll, and the back side is in contact with the suction roll through the felt. The suction press roll is directed from the front side of the paper to the back side. The suction dehydration is performed. Three series of spraying devices were used in which flat watering type spray nozzles (1/4 S0495 manufactured by Niikura Corporation) were arranged at intervals of 5 cm in the width direction of the paper machine.
Other conditions were as follows.
J / W ratio 1.010, reel moisture 7.0%, papermaking speed 360m / min, density, tensile strength, Clark stiffness, and steecht sizing degree of paper base paper obtained without calendering Table 1 shows. Table 1 shows the results of the evaluation of curl, wrinkles, and creaking as the workability of the paper shaft and the sensory evaluation of the shaft strength.

(Example 2)
A base paper for paper shaft was produced in the same manner as in Example 1 except that raw material pulp consisting of 75 parts by mass of NBKP (freeness 600 mlCSF) and 25 parts by mass of LBKP (freeness 460 mlCSF) was used. Table 1 shows the evaluation results of the obtained paper shaft base paper.

(Example 3)
A base paper for paper shaft was produced in the same manner as in Example 1 except that raw material pulp consisting of 75 parts by mass of NBKP (freeness: 500 ml CSF) and 25 parts by mass of LBKP (freeness: 400 ml CSF) was used. Table 1 shows the evaluation results of the obtained paper shaft base paper.

Example 4
A paper base paper was manufactured in the same manner as in Example 3 except that the J / W ratio was 1.000. Table 1 shows the evaluation results of the obtained paper shaft base paper.

(Example 5)
A paper base paper was manufactured in the same manner as in Example 3 except that the J / W ratio was 0.990. Table 1 shows the evaluation results of the obtained paper shaft base paper.

(Example 6)
A base paper for paper shaft was produced in the same manner as in Example 1 except that raw material pulp composed of 20 parts by mass of NBKP (freeness 650 ml CSF) and 80 parts by mass of LBKP (freeness 460 ml CSF) was used. Table 1 shows the evaluation results of the obtained paper shaft base paper.

(Example 7)
A paper base paper was manufactured in the same manner as in Example 6 except that the J / W ratio was 1.015. Table 1 shows the evaluation results of the obtained paper shaft base paper.

(Comparative Example 1)
A paper base paper for paper shaft was manufactured in the same manner as in Example 3 except that the J / W ratio was 0.980 and the addition amount of the acidic rosin sizing agent was 0.3% by mass. Table 1 shows the evaluation results of the obtained paper shaft base paper.

(Comparative Example 2)
Comparative Example 1 except that raw material pulp composed of 40 parts by weight of NBKP (freeness 650 ml CSF) and 60 parts by weight of LBKP (freeness 460 ml CSF) was used, and that the addition amount of the acidic rosin sizing agent was 0.5% by weight. The paper shaft base paper was manufactured in the same manner. Table 1 shows the evaluation results of the obtained paper shaft base paper.

(Comparative Example 3)
A paper base paper was manufactured in the same manner as in Example 3 except that the J / W ratio was 1.020. Table 1 shows the evaluation results of the obtained paper shaft base paper.

(Comparative Example 4)
A paper base for paper shaft was produced in the same manner as in Comparative Example 3 except that the paper strength enhancing agent was not sprayed. Table 1 shows the evaluation results of the obtained paper shaft base paper.

(Comparative Example 5)
A paper base paper was manufactured in the same manner as in Example 6 except that the J / W ratio was 1.020. Table 1 shows the evaluation results of the obtained paper shaft base paper.

The evaluation method of the base paper for the paper shaft is as follows.
(Density) JISP 8118: 1998 Paper and paperboard-Test method for thickness and density (Tensile strength) JISP8113: 2006 Paper and paperboard-Test method for tensile properties-Part 2: Constant speed stretching method (Clark stiffness) JISP8143: 2009 Paper-stiffness test method-Clark stiffness tester method (Steecht sizing degree) JISP8122: 2004 paper and paperboard-sizing degree test method-Sutechitt method

(Paper shaft processing) Paper shaft base paper is cut to a width of 75 mm and a length of 400 mm, wound in the CD direction with a paper shaft processing machine to manufacture a paper shaft, and then cotton is attached to both ends of the winding shaft to manufacture a cotton swab. did.
(Curl evaluation) Evaluation was made in the following three stages according to the processing suitability of the base paper with a paper shaft processing machine. ◎ There was no curl tendency. Δ: There was a tendency to curl, but it could be dealt with by humidification. × Even when the curl is very humid, paper jams frequently occur due to curling.
(Evaluation of wrinkles) 100 samples were randomly sampled from the manufactured cotton swabs and visually checked for the presence or absence of wrinkles, and evaluated in the following three stages. ◎ The number of wrinkles generated in 100 was 1 or less. O The generation of wrinkles out of 100 was 2-3. The occurrence of wrinkles in x100 was 4 or more.
(Evaluation of Mekre) 100 samples were randomly sampled from the manufactured cotton swabs, and the end of the adhesive part of the paper shaft was hooked with a nail to confirm the presence or absence of mekre, and evaluated in the following three stages. ◎ The occurrence of meklet was less than 1 out of 100. ○ The occurrence of meklet out of 100 was 2-3. The occurrence of meklet out of 100 pieces was 4 or more.
(Axial strength evaluation) The feeling of use of the produced cotton swab was evaluated by 10 people. The evaluation criteria are three grades: ◎ Excellent, ○ Axis is slightly soft, can be used, and X is soft and difficult to use.

As shown in Table 1, in Examples 1 to 7 of the present invention, all evaluation results of wrinkles, creaking and axial strength are good. In Comparative Examples 1 to 5, either evaluation is worse.

Since the comparative example 1 has a low tensile strength aspect ratio of 1.24 and a low Clark stiffness aspect ratio of 1.41, the axial strength evaluation is poor. In addition, the degree of steecht size is low, poor adhesion occurs, and the evaluation of mekre is poor.

In Comparative Example 2, since the aspect ratio of tensile strength is as low as 1.39 and the Clark stiffness aspect ratio is as low as 1.49, the evaluation of axial strength is poor.

Comparative Example 3 has a high tensile strength aspect ratio of 2.41, and a Clark stiffness aspect ratio of 2.32. Therefore, the axial strength evaluation is good, but the wrinkle evaluation is poor.

In Comparative Example 4, since the paper strength enhancer was not sprayed, the curl tendency of the base paper was strong, making it difficult to produce the paper shaft, and it was impossible to evaluate each of wrinkles, creaking and shaft strength.

In Comparative Example 5, the aspect ratio of the tensile strength is 2.55, which is the highest among the comparative examples, the curl of the base paper is strong, and it is difficult to manufacture the paper shaft, and it is impossible to evaluate each of wrinkles, creaking and shaft strength. It was.

As described above, in the examples of the present invention, there is no paper sheet for wrinkles and crevices, a good processing suitability, and a high shaft strength.

The base paper for paper shaft of the present invention can be used as a paper shaft for cotton swabs, earpicks, stirring sticks and the like.

Claims (2)

A paper shaft base paper, which is formed by winding and adhering sheet-like paper, and satisfies the following conditions.
(1) NBKP (softwood bleached kraft pulp) and LBKP (hardwood bleached kraft pulp) are used as raw material pulp, and the mass ratio of NBKP and LBKP is 20:80 to 80:20.
(2) The Canadian standard freeness of NBKP is beaten to 400 to 650 ml CSF, and the Canadian standard freeness of LBKP is beaten to 400 to 500 ml CSF.
(3) Basis weight is in the range of 30 to 70 g / m ² .
(4) The Steecht sizing degree is 5 seconds or more.
(5) The paper axis is wound in the CD direction (MD direction is the axis), and the aspect ratio (vertical / horizontal) of the tensile strength is in the range of 1.4 to 2.4.
(6) Clark stiffness has an aspect ratio (vertical / horizontal) in the range of 1.5 to 2.3. 2. The paper shaft according to claim 1, wherein the base paper is single glossy paper, and a paper strength enhancer is spray-applied to the wet paper in the manufacturing process so that the density is 0.70 g / cm ³ or more. Base paper.