JP5455262B2 - Tissue paper products - Google Patents

Description

The present invention relates to tissue paper products.

For tissue paper products, a tissue paper web made of 1 or 2 ply layers of tissue paper is cut into a predetermined size as needed, folded so that it can be taken out continuously, and stored in a box so that a predetermined number of sets are obtained. Manufactured.
In this tissue paper product (web), it is most important in terms of quality to be excellent in strength and softness (a comprehensive sensory of suppleness, smoothness and volume). It is also important to have a soft touch, so-called high bulk (specific volume).

As a method of obtaining tissue paper with a bulky feeling and a soft texture, after making paper by adding a softening agent (cationic agent) to raw pulp having a fiber length and fiber roughness in a predetermined range, creping is performed. A method is known in which a bulky crepe paper is obtained by suppressing interfiber bonding of pulp fibers (Patent Document 1).
Further, as a mechanical treatment for obtaining a high bulk tissue paper, a method TAD (through air drying) method (patent document 2) in which a wet paper is air-dried without press-dehydrating in a dehydration drying process of the paper making process. ), And a method of performing uneven processing on the wet paper web between the formation of the wet paper and the drying process.
Furthermore, there is a method of mechanically treating the web after paper making by embossing or the like. Further, these methods may be combined.
However, in the case of the internal addition method using the softening agent described above, the cost of the medicine is high, and the fiber-to-fiber bond of the pulp is lowered, so the strength of the web is lowered, the generation of paper dust is further increased, and the water absorption rate is lowered. There is a problem.
Further, in the case of the above TAD method, the cost of the drying energy becomes enormous. Furthermore, in the method of performing unevenness treatment after paper making, the bond between fibers and the paper layer structure are broken, the web strength is lowered, or the apparent bulk of the web is increased, but the paper layer bulk (caliper) of the web itself is increased ( There is a problem that it is difficult to produce a soft feeling).

On the other hand, in the conventional paper making of tissue paper, the wet paper web is pressed against the Yankee dryer at one or two roll press nips through the felt, dehydrated, further attached to the Yankee dryer (cylinder), and then dried. Creping (crease) is performed when the web is peeled off from the dryer. Moreover, in a press part, like a double felt machine, it presses with the top and bottom rolls of a wet part, and dehydrates, and it may press against a Yankee dryer by a roll press nip after that.
However, there is a problem that the web becomes relatively low bulk due to the pressing to the Yankee dryer. And even if it tries to suppress the bulk fall by creping by adding the above-mentioned bulking agent to a pulp raw material, only the bulkiness effect of about 3 to 5% is obtained at most, On the other hand, intensity | strength falls remarkably.
In addition, the TAD method described above is a technique in which the final drying and creping are performed with a Yankee dryer and dehydrated with a vacuum, and preliminarily dried with a ventilating dryer. And a high bulk web is obtained. However, since the TAD method removes moisture equivalent to press nip dehydration by ventilation heat, it is said that about twice as much drying energy is required as compared with the conventional roll press nip method.

Therefore, as a method of performing high bulk processing in the wet paper process without using the TAD method, a method of adjusting pressure dehydration by a wide press nip called a shoe press method has been proposed (Patent Document 3). The shoe press method can obtain a higher bulk and softness than the conventional roll press nip method, but cannot obtain a higher bulk than the TAD method.
Furthermore, as a method for solving these problems, a paper machine called a fabric press system has been developed (Patent Document 4). The fabric press method follows the conventional press technology, but is provided with unevenness on the web by means of an uneven belt or fabric simultaneously with dewatering. This dewatering and roughening is performed in one or more press nips while the wet web is fed from the felt to the roughening belt, and then the web is transported to a Yankee dryer and dried.
According to the fabric press method, a high bulk equivalent to the TAD method can be obtained while the drying energy is equivalent to that of the conventional roll press nip method.

The structure of the web by the fabric press method is not a woven fabric, but forms a three-dimensional pattern similar to the woven fabric. This is considered because web unevenness is performed as follows. That is, during the pressing process, the fibrous network fills the three-dimensional pattern (pattern) of the concavo-convex belt, but at that time, the three-dimensional pattern of the concavo-convex layer forms a wet fibrous web. Is granted. The wet fibrous webs are moveable relative to each other, so that they take a new position and orientation relative to each other due to the elastic compression of the press felt. Press felt presses the wet fibrous web against the three-dimensional pattern of the textured belt, thereby increasing bulk and softness with the same basis weight and an improved structure.
The bulk of the web is then maintained uncompressed by receiving a fibrous network (network) in cavities in the belt structure while dewatering in the press nip.

JP 2006-97191 A JP-A-8-3890 JP-A-6-158578 Special table 2001-521999 gazette

However, even if the technique described in Patent Document 4 is used, it is sufficient to satisfy both the high strength, bulkiness (high specific volume), and good touch (excellent softness) of the tissue paper web and its product. I couldn't.
Accordingly, an object of the present invention is to provide a tissue paper product having both high strength, bulkiness and good tactile sensation.

In order to solve the above-described problems, the tissue paper product of the present invention is a tissue paper product in which a single sheet or a plurality of plies are stacked, and has a warp and weft on the top surface (surface where the wet paper and the wire are in contact). Each of the webs is made of a concavo-convex fabric made of a mesh-like wire knitted with warps and wefts having a diameter of 20 to 70 / 2.54 cm, and the warp and weft wire diameters of 0.21 to 0.70 mm. The calendering is performed with a thickness t ₀ of 80 to 300 μm / sheet, the basis weight of one single sheet is 10 to 40 g / m ² , and the tissue paper product has a specific volume of 6.7. ~10.0cm ³ / g, and it is the square root of the product of the tensile strength DMDT the longitudinal direction during the drying based on JIS P8113, a transverse tensile strength DCDT when dry (DMDT × CDT) ^1/2 (GMT) is characterized in that it is a 1.6~4.0N / 25mm.

It is preferable that the calendering is performed with a pair of rolls having a gap of 20 to 80% with respect to the paper thickness after the papermaking and drying.
The tissue softness measuring device TSA is used to push the bladed rotor against the sample of the tissue paper product placed on the sample stage from the top with a pressure of 100 mN, and then rotate at a rotation speed of 2.0 (/ sec). The intensity of the maximum peak (TS750) of the first spectrum from the low frequency side automatically acquired by the software on the TSA when the vibration of the sensor is measured with a vibration sensor is 7 to 25 dBV ² rms, including 6500 Hz It is preferable that the intensity (TS7) of the maximum peak in the spectrum is 8 to ²⁰ dBV ² rms .

  According to the present invention, a tissue paper product having both high strength, bulkiness and good tactile sensation can be obtained.

It is a figure which shows an example of the manufacturing apparatus of the tissue paper web which concerns on embodiment of this invention. It is a figure which shows the structure of the calendar part at the time of manufacturing the tissue paper web which concerns on embodiment of this invention. It is a figure which shows the measurement principle of tissue softness measuring apparatus TSA. It is a figure which shows an example of the analysis result of the vibration frequency of the paper sample sample by TSA. It is a figure which shows the measuring method of the rigidity D of the paper sample sample by TSA.

Embodiments of the present invention will be described below.
The tissue paper product according to the embodiment of the present invention is formed by stacking one ply or a plurality of plies of a single sheet, and has a basis weight of 10 to 40 g / m ² and a specific volume of 6.7 to 10. 0 cm ³ / g. Also, the product of the tensile strength DMDT (Dry Machine Direction Tensile strength) in the dry direction and the transverse tensile strength DCDT (Dry Cross Direction Tensile strength) in the dry direction according to JIS P8113 of the tissue paper product. The square root (DMDT × DCDT) ^1/2 (GMT: Geometric Tensile Strength) is 1.6 to 4.0 N / 25 mm.
In addition, the flow direction of the tissue paper web and the paper making of the product is defined as “longitudinal direction”, and the direction perpendicular to the flow direction is defined as “lateral direction”.

When the basis weight of one single sheet is less than 10 g / m ² , the strength is lowered, and when it exceeds 40 g / m ² , the softness is inferior. The basis weight is preferably 10 to 30 g / m ² , more preferably 10 to 25 g / m ² , and still more preferably 10 to ²⁰ g / m ² .
When the specific volume of the tissue paper product is less than 6.7 cm ³ / g, the soft feeling is poor and the texture is inferior. On the other hand, if the specific volume exceeds 10 cm ³ / g, the bulk (bulkiness) becomes high, but the smoothness is inferior and the tactile sensation becomes worse. The specific volume is preferably 6.7 to 9.0 cm ³ / g, more preferably 6.7 to 8.0 cm ³ / g.
Further, if the tissue paper product has a GMT of less than 1.6 N / 25 mm, the tissue paper product is easily shaken and is not suitable for practical use. When GMT exceeds 4.0 N / 25mm, it will become hard and softness will be impaired. The GMT is preferably 1.6 to 3.5 N / 25 mm, more preferably 1.7 to 3.0 N / 25 mm, and still more preferably 1.8 to 3.0 N / 25 mm.
The tissue paper product which concerns on embodiment of this invention can satisfy | fill both high intensity | strength, bulkiness, and a favorable tactile sense by prescribing | regulating a basic weight, a specific volume, and GMT to the said range.

The tissue paper product may consist of 100% wood pulp and may contain waste paper pulp and non-wood pulp. In order to obtain the target quality, it is preferable to use wood pulp of NBKP: LBKP = 10: 90 to 70:30 (mass ratio) as a raw material, and a more preferable range is NBKP: LBKP = 20: 80 to 70: 30 and a more preferable range is NBKP: LBKP = 20: 80 to 40:60. Pulp produced from Eucalyptus eucalyptus represented by Eucalyptus grandis and Eucalyptus globulus is preferred as the grade of LBKP. Moreover, the waste paper pulp can be contained up to about 50% by mass with respect to the wood pulp having this pulp ratio. Waste paper pulp has a large variation in quality, and as the blending ratio increases, the quality of the product, particularly the softness, is greatly affected. Therefore, it is desirable to blend 20% by mass or less with respect to the wood pulp.
In addition, in order to ensure appropriate strength for tissue paper products, raw materials can be blended by ordinary means, and the strength can be adjusted by beating the pulp fibers. As the beating for obtaining the target quality, 0 to 100 ml, more preferably 0 to 50 ml, and further preferably 10 to 40 ml of filtered water with respect to a commercially available virgin pulp in Canadian standard freeness measured by JIS P8121. Reduce the degree.
Details of the tissue paper web manufacturing method will be described later.

When the tissue paper product according to the embodiment of the present invention is measured by a tissue softness measuring apparatus TSA (Tissue Softness Analyzer), the maximum peak of the first spectrum from the low frequency side automatically acquired by software on the TSA preferably strength (TS750) is 7~25dBV ² rms, and more preferably 7~21dBV ² rms, more preferably 7~18dBV ² rms, and most preferably 7~15dBV ² rms. When TS750 is higher than 25 dBV ² rms, the smoothness is inferior, and when TS750 is lower than 7 dBV ² rms, only the smoothness is prominent and a good tactile sensation may not be obtained.
Further, the automatically acquired by software on the TSA, preferably the intensity of the maximum peak of the spectrum containing 6500Hz (TS7) is 8~20dBV ² rms, and more preferably 8~17dBV ² rms, and most preferably 8-15 dBV ² rms. When TS7 is higher than 20 dBV ² rms, sufficient softness cannot be obtained, and when TS7 is lower than 8 dBV ² rms, only softness may stand out and good tactile sensation may not be obtained.
Also, the stiffness (D) measured by TSA is preferably 2.3 to 4.5 mm / N, more preferably 2.6 to 4.5 mm / N, and most preferably 2.9 to 4.5 mm. / N. When the measured D value is lower than 2.3 mm / N, the overall tissue paper product is inferior, and when it is higher than 4.5 mm / N, the suppleness is conspicuous and the overall balance may be lacking.

Here, as shown in FIG. 3, the tissue softness measuring apparatus TSA 210 performs vibration analysis on vibration data detected by various sensors when the rotated bladed rotor 204 is pressed on the paper sample (sample) 206. By parameterizing (TS value), the softness of the paper (feel) is quantitatively evaluated. The product name of Emtec Electronic GmbH (Germany is Japan Luft Co., Ltd.) It is.
For specific measurement using TSA, (i) Install sample 206 (sample processed into a circle with a diameter of about 112.8 mm using emtec sample punch) to cover the circular sample stage 205 from the outside. The outer periphery of the sample 206 is held by the sample fixing ring 208. (ii) After the bladed rotor 204 is pushed from above the sample 206 with a pushing pressure of 100 mN, the rotor 204 is rotated at a rotation speed of 2.0 (/ sec). (iii) The vibration of the sample table 205 is measured by the vibration sensor 203 installed in the sample table 205, and the vibration frequency is analyzed. (iv) Next, when the indentation pressure is 100 mN and 600 mN, the amount of deformation (mm / N, rigidity D) in the vertical direction when the sample 206 is deformed without rotating the rotor 204 is measured. By the procedures (i) to (iv), the elements (smoothness, suppleness, volume feeling) of the overall hand feel value of the tissue paper product can be quantified. The measurement is repeated 5 times for each sample and averaged. In addition, the front and back means both sides facing the outside of the product if the tissue paper is a 2ply product (that is, the surface opposite to the sheet overlapping surface), and both sides of a single sheet if it is a 1ply product.
The sample stage 205 is installed on the base plate 201, and a force sensor 202 is disposed between the sample stage 205 and the base plate 201. Then, the pushing pressure of the bladed rotor 204 is controlled by the detection value of the force sensor 202. The bladed rotor 204 is rotated by a motor 209.
In addition, emtec measurement system is used as software for analyzing vibration and parameterizing (TS value). This software is equipped with various algorithms (for example, Base Tissue, Facial, TP, etc.), TS7, TS750, D are automatically acquired on the software, and these TS7, TS750, D, basis weight, thickness The HF (hand feel) value is calculated according to the type of various algorithms from the Ply number and the like. In the present invention, only the TS7, TS750, and D are defined, not the HF values, and any algorithm may be used as long as the above measurement conditions are satisfied. The values of TS7, TS750, and D depend on the algorithm type. It will not change.

FIG. 4 shows an example of the analysis result of the vibration frequency of the paper sample sample by TSA. The intensity of the maximum peak A of the first spectrum from the low frequency side is TS750, and the intensity of the maximum peak B of the spectrum including 6500 Hz (around 6500 Hz) is TS7. The maximum peak B is usually located at about 6500 Hz.
FIG. 5 shows a method for measuring the stiffness D of a paper sample sample by TSA.

The vibration frequency of the paper sample sample depends on the paper structure and the number of rotations of the rotor 4, and the amplitude (spectrum intensity) depends on the height of the paper structure such as the height of the crepe. TS750, which is the first peak of the spectrum (A in FIG. 4), represents smoothness and roughness. On the other hand, the frequency at which TS7 appears (in the range of 5000 to 8000 Hz, usually around 6500 Hz) is the resonance frequency of the rotor 4. Due to vibration. The rigidity D correlates with the rigidity (tensile strength) of the paper.
The lower the TS7 value, the better the soft feeling (surface softness and bulk softness), and the lower the TS750 value, the better the smoothness. Moreover, the greater the value of D, the more flexible.
Further, based on the functions of TS7, TS750, and D, a comprehensive hand feel value (HF value) can be calculated.
For example, by setting a function of (HF value) = A × (TS7) + B × (TS750) + C × (D) + α, the total hand feel value can be objectively (quantitatively) quantified. Here, A, B, C, and α are coefficients. By appropriately setting these coefficients, softness and smoothness corresponding to the factors constituting the hand feel value (that is, TS7, TS750, and D, respectively). , Stiffness) weighting can be adjusted to match the actual soft sensory evaluation.
When A and B are negative values and C is a positive value, the larger the hand feel value, the better the overall softness.

  The tissue paper product of the present invention is formed so that the above-described tissue paper web is overlapped (preferably 1 to 3 sheets) in one ply or a plurality of plies, and is cut into sheets of a predetermined size as appropriate, so that it can be continuously taken out. It can be manufactured by folding and stacking each other to a predetermined number. Moreover, this laminated body can be stored in a box.

Next, a tissue paper web manufacturing method according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows an example of a tissue paper web manufacturing apparatus 50, and FIG. 2 shows the structure of a calendar part.
The apparatus 50 shown in FIG. 1 is a fabric press type paper machine, and can produce the web 103 with unevenness only by pressing means without using a ventilation drying (TAD) facility for preliminary dehydration. The apparatus 50 includes a wet part 2 for forming a continuous web, a press part 3 for dewatering the web to be patterned or uneven, and a drying part 4 for finally drying the web.

The wet section 2 forms a wet paper in the form of a crescent former, a head box 6 for supplying a stock made of fiber and water to the forming area, a forming felt 8 for dehydrating a part of the water of the web, and the forming. It has a wire 9, a plurality of guide rolls 10, and a forming roll 7.
The head box 6 discharges a paper jet at a molding portion 5 between the forming wire 9 and the forming felt 8. The forming wire 9 has an endless loop shape, travels around the plurality of guide rolls 10 and the forming roll 7, and contacts the forming felt 8 with the forming roll 7. Accordingly, the stock discharged to the position 5 is dehydrated by the forming wire 9 to form the fibrous web 101, and the fibrous web 101 is conveyed to the press unit 3 by the forming felt 8. The forming felt 8 is also in the form of an endless loop that travels around a plurality of guide rolls 18.
In addition, the shaping | molding part 5 can also be used as a suction breast roll former.

The press unit 3 includes a main press 11 and a textured fabric 14, and the main press 11 includes a first press element 12 and a second press element 13. The first and second pressing elements 12, 13 are pressed together to form a press nip N1 therebetween. In the example of FIG. 1, the main press 11 is a roll press and forms a twin roll in which the first and second pressing elements 12 and 13 face each other. And the 1st press element (roll) 12 is located in the loop of the uneven | corrugated fabric 14, the 2nd press element (roll) 13 is located in the loop of the forming felt 8, and forms felt at the press nip N1. 8 and the textured fabric 14 come into contact. The main press 11 may be a long nip press or a shoe press (not shown).
The uneven fabric 14 has an endless loop shape and runs around a plurality of guide rolls 15 and a smooth transfer roll 16 facing the drying unit 4. The uneven fabric 14 contacts with the fibrous web 101 conveyed by the forming felt 8 through the press nip N1 of the main press 11 when traveling around the first press element (roll) 12. And in the press nip N1, the uneven | corrugated fabric 14 dehydrates and uneven | corrugates the fibrous web 101, and forms the uneven | corrugated fibrous web 102. FIG. The uneven fibrous web 102 is conveyed to the transfer roll 16 by the uneven fabric 14.
The transfer roll 16 faces a drying cylinder 19 of the drying unit 4 described later, and forms a transfer nip N2 therebetween. And the uneven | corrugated fibrous web 102 conveyed by the transfer nip N2 is provided only to drying, without performing press and spin-drying | dehydration.

In the press section 3 (press nip N1), the forming felt 8 functions as a water-receiving press felt 17 that is elastically deformable and compressible in the z-direction (thickness direction). The water-receiving press felt 17 immediately separates the textured fibrous web 102 that has passed through the press nip N1, and prevents the web 102 from being wetted again.
While passing through the press section 3, the dryness of each of the webs 101, 102 can be in the range of fiber concentration 15-30% to 42-52%.

The drying unit 4 includes a drying cylinder 19, a creping doctor 21, and a hood 22 that covers the drying cylinder 19. In the example of FIG. 1, the drying cylinder 19 is a Yankee dryer, but other types of drying units (for example, an air-through dryer or a metal drying belt) can be applied. Further, the drying unit may be a single drying unit (for example, one cylinder as shown in FIG. 1), or may be constituted by a plurality of drying units.
The surface of the drying cylinder 19 forms a drying surface 20 for drying the textured fibrous web 102 in the vicinity of the transfer nip N2. The creping doctor 21 is also disposed downstream of the drying surface 20 and crepes the concavo-convex fibrous web 102 dried by the drying surface 20, thereby providing a final web that has been both concavo-convex and creped. Is obtained. With crepe is a known method in which paper is mechanically compressed in the machine direction (machine running direction) to form a wavy crease called crepe, and the paper is bulky, soft and water-absorbing. , Imparts surface smoothness, aesthetics (crepe shape), etc.
Then, the uneven fibrous web 102 is transferred from the uneven fabric 14 to the drying surface 20 of the drying cylinder 19 at the transfer nip N2. The pressure in the transfer nip N2 is 1 MPa or less, and the web 102 does not dehydrate at this pressure.
In order to reliably transfer the web 102 from the uneven fabric 14 to the dry surface 20 side, an adhesive may be applied to the dry surface 20 by the spray device 23. The spray device 23 can be placed between the creping doctor 21 and the transfer nip N2 at a position where the drying surface 20 is open.

Examples of the uneven fabric 14 include a mesh-like wire in which metal or synthetic resin (plastic) wires are knitted in the vertical and horizontal directions as warps and wefts. As the number of the wires, the number of warps and wefts may be 20 to 70 / 2.54 cm, preferably 20 to 65 / 2.54 cm, and more preferably 25 to 60 / 2.54 cm. The wire diameter of the wire may be 0.21 to 0.70 mm, preferably 0.21 to 0.55 mm, more preferably 0.21 to 0.45 mm.
When the number of warps and wefts is less than the above range, or when the diameters of the warp and wefts exceed the above range, the unevenness of the surface of the uneven fabric 14 is too strong and the unevenness of the surface of the obtained web is also strong. Too much and the touch (excellent softness) is inferior.
When the number of warps and wefts exceeds the above range, or when the diameters of the warp and weft are less than the above range, the unevenness of the surface of the uneven fabric 14 is too low, and the unevenness of the surface of the obtained web is also It becomes low and it is difficult to obtain bulkiness (high specific volume) while ensuring strength.
In addition, the general fabric which is not an uneven | corrugated fabric has the number of eyes of a warp and a weft about 70-200 piece / 2.54cm, respectively. The diameters of the warp and the weft are about 0.08 to 0.20 mm.
The number of wires and the wire diameter shown above are the values of the top surface of the wire (surface on which the wet paper and the wire are in contact).

Next, with reference to FIG. 2, the calendar process which is the characteristic part of the manufacturing method of the tissue paper web which concerns on embodiment of this invention is demonstrated.
The calender part 60 is composed of a pair of opposed rolls 61 and 62, and the paper making and the uneven fibrous web 103 after drying are inserted into the gap between the rolls 61 and 62 and calendered.
Here, with respect to the thickness t ₀ of the uneven fibrous web 103, the gap distance t ₁ between the rolls 61 and 62 is set to 20 to 80%, and the top roll and bottom roll of the calendar are ± 5%. By giving the difference in rotational speed within the range, a smoother and more flexible bulky web can be obtained.
When the distance t ₁ is less than 20% of the thickness t ₀ , the web becomes smooth, but valcross is generated, and a bulky and fluffy web having a specific volume of 6.7 to 10.0 cm ³ / g cannot be obtained. If the distance t ₁ exceeds 80% of the thickness t ₀ , it becomes difficult to smooth the web.
If the distance t ₁ is 20 to 80% of the thickness t ₀ , the caliper (thickness) of the web that has passed the rolls 61 and 62 is restored to some extent naturally, minimizing caliper reduction, flexibility, The surface property can be improved while minimizing the thickness reduction.
As the rolls 61 and 62, a steel roll, a chilled roll, a metallic roll such as a surface hard plating finish roll, or a cylinder coated with an elastic material can be used. A metal roll is preferable in that the web can be made smoother.
The web thickness t ₀ before calendering is preferably 80 to 300 μm / sheet, more preferably 100 to 300 μm / sheet, and further preferably 200 to 300 μm / sheet. The web thickness after calendering is preferably 50 to 200 μm / sheet, more preferably 100 to 200 μm / sheet.
The thickness of the tissue paper product in which one or more plies of a creped and calendered single sheet are stacked is 0.5 to 1.5 mm / 10, preferably 0.5 to 1.1 mm / 10 is there.
In the processing of tissue paper products, the presence / absence of application of lotion chemical, the presence / absence of embossing, and the presence / absence of printing can be selected as appropriate.

  It goes without saying that the present invention is not limited to the above-described embodiments, and extends to various modifications and equivalents included in the spirit and scope of the present invention.

The pulp composition (mass%) is set to NBKP 30% and LBKP 70%, and the two-ply and one-ply tissue papers having the characteristics shown in Table 1 and Table 2, respectively, are used in the fabric press type paper machine 50 shown in FIG. An uneven fibrous web 103 was produced. Next, using the pull unit calendar part 60 shown in FIG. 2, the papermaking and the textured fibrous web 103 after drying were calendered. Tables 1 and 2 show the calendering conditions.
As the concavo-convex fabric 14, a mesh-like plastic wire knitted longitudinally and laterally as warp and weft is used. The number of warps and wefts and the wire diameter of the wire are 53 warps / 2.54cm. Number of stitches: 34 / 2.54 cm, warp wire diameter: 0.30 mm, weft wire diameter: 0.35 mm

Furthermore, the final web after calendar processing was processed into two-layer and single-layer tissue paper products, and the following evaluations were performed.
GMT (Geometric Tensile Strength): Based on JIS P8113, the longitudinal tensile strength DMDT during drying and the transverse tensile strength DCDT during drying were measured, and the square root of these products was calculated.
Basis weight: measured based on JIS P8124.
Thickness: Measured using a thickness gauge (a dial thickness gauge “PEACOCK” manufactured by Ozaki Seisakusho). The measurement conditions were a measurement load of 250 gf and a probe diameter of 30 mm. A sample was placed between the probe and the measurement table, and the gauge was read when the probe was lowered at a speed of 1 mm or less per second. The measurement was performed at 10 different points by stacking 10 samples, and the measurement results were averaged. Then, the average value obtained was divided by the number of sheets to obtain the paper thickness per sheet.
Specific volume: Thickness per sheet divided by basis weight and expressed in volume cm ³ per unit g.
Water absorption: In accordance with the old JIS-S3104 method, in a state of a temperature of 23 ± 1 ° C. and a humidity of 50 ± 2%, 0.01 ml for a single-layer product and 0.1 ml of purified water for a double-layer product are dripped, and water drops Was measured for the time (seconds) taken by tissue paper products.

TS7, TS750, and D were measured using the tissue softness measuring apparatus TSA. The measurement conditions are also as described above.
The softness was evaluated by sensory evaluation by 20 monitors. The evaluation standard was a full score of 10 points, and a relative evaluation was performed with 5 blanks for each test. If the evaluation is 6 points or more, the softness is excellent.
The basis weight, tensile strength (GMT), thickness, specific volume, and tissue softness measuring device TSA are measured under the temperature and humidity conditions specified in JIS-P8111 (23 ± 1 ° C, 50 ± 2% RH). ) Was performed after maintaining the equilibrium state.

  The obtained results are shown in Table 1 for the two-layer tissue paper products and shown in Table 2 for the one-layer tissue paper products.

As is clear from Tables 1 and 2, in each example, the specific volume was 6.7 to 10.0 cm ³ / g, the GMT was 1.6 to 4.0 N / 25 mm, and the sensory evaluation of softness It was excellent in strength, bulkiness (specific volume), and softness.

On the other hand, in the case of Comparative Examples 1 to 3 in which the basis weight of one single sheet is less than 10 g / m ² , the GMT is less than 1.6 N / 25 mm and the strength is reduced, and compared to the blank 1 (no calendering). There was no improvement in hand feel. In Comparative Example 1, the specific volume was less than 6.7 cm ³ / g, and the web thickness before calendering of Comparative Examples 1 to 3 was less than 200 μm.
Moreover, in the case of the comparative example 6 whose specific volume is less than 6.7 cm < ³ > / g, while GMT became less than 1.6 N / 25mm and intensity | strength fell, the improvement of the hand feel compared with the blank 5 (no calendar processing) is I couldn't see it.
In the case of Comparative Examples 4 and 5, which are commercially available products, the specific volume was less than 6.7 cm ³ / g, and no improvement in hand feel was observed. This is because in the case of Comparative Examples 4 and 5, paper was made without using the uneven fabric 14 described above. The GMT (strength) can be appropriately adjusted depending on, for example, the raw material of the pulp and its blending amount, the beating degree, the presence / absence of addition of a paper strength agent, papermaking conditions, and the like.

60 Calendar parts 61, 62 A pair of calendar part rolls 61 A top calendar roll 62 A bottom calendar roll 130 A web after paper making and drying t _{0 A} paper thickness after paper making and drying t ₁ A gap distance between _one pair of rolls

Claims (3)

A tissue paper product in which a single sheet is laminated with one or more plies,
The top surface (the surface where the wet paper and the wire come into contact) has a warp and weft mesh number of 20 to 70 / 2.54 cm, and the warp and weft wire diameter is 0.21 to 0.70 mm. Paper is made with a textured fabric consisting of
The calendering is performed by setting the web thickness t ₀ before calendering to 80 to 300 μm / sheet,
The basis weight of one single sheet is 10 to 40 g / m ² ,
The tissue volume of the tissue paper product is 6.7 to 10.0 cm ³ / g, and the product of the tensile strength DMDT in the vertical direction when dried according to JIS P8113 and the tensile strength DCDT in the transverse direction when dried A tissue paper product having a square root (DMDT × DCDT) ^1/2 (GMT) of 1.6 to 4.0 N / 25 mm. The tissue paper product according to claim 1, wherein the calendering is performed by a pair of rolls having a gap of 20 to 80% with respect to the paper thickness after papermaking and drying. The tissue softness measuring device TSA is used to push the bladed rotor against the sample of the tissue paper product placed on the sample stage from the top with a pressure of 100 mN, and then rotate at a rotation speed of 2.0 (/ sec). When measuring the vibration of the
The intensity of the maximum peak (TS750) of the first spectrum from the low frequency side automatically acquired by software on the TSA is 7 to 25 dBV ² rms, and the intensity of the maximum peak (TS7) of the spectrum including 6500 Hz is The tissue paper product according to claim 1 or 2, which is 8 to ²⁰ dBV ² rms .