JP2009028457A - Sanitary tissue and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide single-embossed, nice and soft sanitary tissue. <P>SOLUTION: The sanitary tissue is embossed by using an emboss roll having an emboss pattern constituted of unit embossing projection parts having a truncated corn or truncated elliptic corn shape where the area of the top surface part is 0.3-1.8 mm<SP>2</SP>, the tapered angle is 20-50°, and the height is 0.3-1.5 mm. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sanitary thin paper having an emboss and a method for producing the same.

Embossing (unevenness) is often imparted to sanitary thin paper for the purpose of improving functionality such as bulkiness, flexibility and absorbency, and improving design.
Several proposals have been made as embossing modes, for example, so-called single embossing, in which embossing pattern is pressed only from one side, concave embossing on one side and convex embossing on the other side, In this case, so-called double embossing such as a Tip to Tip form or a Nested form in which both surfaces are concave embossed is known.
Among these, single embossing has an advantage that it can be easily applied as compared with other forms, and is widely spread. However, it also has a drawback that roughness is felt on the surface on which the convex emboss is formed.
In particular, in the case of single embossing, it is often performed to make an embossed pattern that draws a pattern similar to a geometric pattern, a leaf pattern, a floral pattern, or a paisley by a straight or curved embossed row formed by continuously arranging unit embosses. . However, although this embossed pattern can obtain an excellent design, the rough feeling of the convex embossed surface is more likely to be felt.
On the other hand, as a use of sanitary thin paper, it is sometimes used as tissue paper that is stored in a carton box having a take-out port with a film having a slit on the upper surface and taken out one by one from the slit.
However, sanitary thin paper with single embossing has convex embossing on one side, so paper dust is likely to be generated when taking out from the slit, and it is easy to feel rough when sniffing, so it is used for pop-up tissue paper It was not suitable for.
JP 2002-369765

  Therefore, the main problem of the present invention is to reduce the feeling of roughness when touching the skin in the sanitary thin paper having convex embossing on one side like embossing, and to make it feel better. Another subject is to be able to use suitably for the tissue paper product taken out in a pop-up form.

The present invention that has solved the above problems is as follows.
<Invention of Claim 1>
Sanitary thin paper with embossing,
Unit emboss having a circular or elliptical shape in plan view has a pattern drawn by a straight or curved emboss row formed in parallel at intervals of 1.0 to 3.0 mm,
A part or all of the unit emboss forms an embossed convex portion on one surface,
And the difference of the paper thickness of a non-embossed part and an embossed part is 50-500 micrometers, The difference of the average deviation MMD of the friction coefficient of the surface in which the said embossing convex part is formed, and the surface in which an embossing recessed part is formed is A sanitary thin paper provided with embossing characterized by being 1.0 or less.

<Invention of Claim 2>
The sanitary thin paper according to claim 1, wherein the total area of the embossed portion is 3 to 30%.

<Invention of Claim 3>
The sanitary thin paper according to claim 1 or 2, wherein the extension length of the embossed rows is 10 mm or more, and the distance between the embossed rows is 1 to 10 mm.

<Invention of Claim 4>
A truncated cone or elliptical truncated cone having a top surface area of 0.3 to 1.8 mm ² , a taper angle of 20 to 50 degrees, and a height of 0.3 to 1.5 mm, or a solid in which these top edges are chamfered Between a pair of embossing rolls composed of an embossing roll having an embossing pattern composed of unit embossing convex portions and a nip roll, a paper thickness of 70 to 300 μm under a nip pressure of 5 to 30 kg / cm, the basis weight 10~40g produced through / m ² of the sanitary thin paper, sanitary thin paper according to any one of claims 1 to 3.

<Invention of Claim 5>
A method for producing a sanitary thin paper having an emboss for forming an emboss on a sanitary thin paper through a sanitary thin paper between a pair of embossing rolls composed of a nip roll and an embossing roll having an embossing pattern,
The sanitary thin paper has a paper thickness of 70 to 300 μm and a basis weight of 10 to 40 g / m ² .
The unit embossing convex portion constituting the embossing pattern is a truncated cone having a top surface area of 0.3 to 1.8 mm ² , a taper angle of 20 to 50 degrees, and a height of 0.3 to 1.5 mm. Oval frustum or a solid unit embossing convex part with chamfered top edges thereof,
The nip pressure between the embossing rolls is 5 to 30 kg / cm.
The manufacturing method of the sanitary thin paper characterized by the above-mentioned.

<Invention of Claim 6>
The said embossing pattern is a manufacture of the sanitary thin paper of Claim 5 which is a pattern by which a unit embossing convex part is drawn by the embossing convex part row | line | column of a straight line or a curve paralleled with the space | interval of 1.0-3.0 mm. Method.

<Invention of Claim 7>
The said embossing roll is a manufacturing method of the sanitary thin paper of Claim 5 or 6 whose total area of an embossing provision convex part is 3 to 30% of an embossing provision roll surface.

<Invention of Claim 8>
The sanitary thin paper according to any one of claims 5 to 7, wherein the length of the straight line or curved line by the embossed convex part row is 10 mm or more and the distance between the straight lines or the curved lines is 1 to 10 mm. Production method.

As described above, according to the present invention, in the sanitary thin paper to which single embossing is applied, the feeling of roughness and unevenness when touching the skin is reduced, and the touch is excellent.
Further, it can be suitably used for tissue paper products taken out in a pop-up format.

Next, embodiments of the present invention will be described in detail below with reference to the drawings.
[Sanitary thin paper with emboss]
FIG. 1 is a plan view of a sanitary thin paper X1 having an emboss 10 according to an embodiment of the present invention. FIG. 2 shows a sectional view taken along the line II-II.

The illustrated sanitary thin paper X1 is a sanitary thin paper provided with a so-called single emboss having an embossed convex portion 11 on one side and an embossed concave portion 12 corresponding to the embossed convex portion 11 on the other side.
The number of plies is not particularly limited, but is about 1 to 3 plies, preferably 2 plies for tissue paper use.
The sanitary thin paper X1 of this embodiment has a pattern by the emboss 10 in a plan view.

The emboss 10 is a straight or curved emboss row 1L (unit 1L in the figure is an emboss row) in which unit embosses 1 having a circular or elliptical shape in plan view are formed in parallel at intervals of 1.0 to 3.0 mm. The same is applied hereinafter, and the pattern is drawn on the sanitary thin paper by the embossed rows. When the thickness is less than 1.0 mm, the clarity of the embossing is lowered, and when it exceeds 3.0 mm, the touch is deteriorated.
The extension length of the embossed rows 1L is preferably 10 mm or more, and the distance D1 between the embossed rows is preferably 1 to 15 mm (in addition, the portion indicated by the symbol D1 in the figure is an example) Yes, not limited to this site). When the embossed row is in this range, the pattern is easily visible.

  The specific example of the pattern is not particularly limited. In addition to the ivy pattern shown in the illustration, geometric patterns such as circles, triangles and rectangles, plants such as flowers, trees and grass, creatures such as people, animals, fish, shellfish and insects, mountains, rivers, seas, Examples include nature such as clouds, forests, and forests, planets and satellites such as the moon, sun, and stars, patterns of artifacts such as cars, airplanes, and trains, and other characters and designs that are a combination of these.

  On the other hand, as for the sanitary thin paper X1 of this form, it is desirable that the total area of an embossed part is 3 to 30%. That is, it is desirable that the ratio of the total area of the unit embossed convex portion or the concave portion in a plan view with respect to the total area of the one surface is in the range of 3 to 30%. If it is this range, an embossed part will be clearly visually recognized with respect to a non-embossed part, and a pattern will become clear. Further, if the total area is less than 3%, the softening effect due to embossing decreases, and if it exceeds 30%, the portion crushed by embossing increases, which also reduces the softening effect.

On the other hand, in the sanitary thin paper X1 of this embodiment, the difference T2 between the paper thickness T1 of the non-embossed portion and the paper thickness of the embossed portion is 50 to 500 μm. If the difference is less than 50 μm, the embossing becomes indistinct and the pattern becomes blurred, and if it exceeds 500 μm, the surface becomes rough when touched. The paper thickness of the non-embossed part is preferably 70 to 300 μm. If it exceeds 300 μm, it becomes hard and is not particularly suitable for tissue paper applications.
The paper thickness in the case of calculating the paper thickness difference here is measured by a laser microscope (for example, VK-9510 manufactured by Keyence Corporation).

On the other hand, the basis weight according to JIS P 8124 of the sanitary thin paper X1 of this embodiment is 10 to 40 g / m ² as a whole regardless of the number of plies. When the number of plies is set, the basis weight of each ply is adjusted so as to be within the range of the basis weight. The reason why the lower limit of the basis weight is defined as 10 g / m ² is that if it is less than 10 g / m ² , it is preferable from the viewpoint of improving softness, but the strength cannot be ensured properly. Further, the upper limit was defined as 40 g / m ^2, when greater than 40 g / m ^2, too hard, because the feel is deteriorated.

On the other hand, in the sanitary thin paper X1 of this embodiment, the difference in the average deviation MMD of the friction coefficient between the surface where the embossed convex portion is formed and the surface where the embossed concave portion is formed is 1.0 or less. When tissue paper products are used, both front and back surfaces are preferred, so that there is no difference between the front and back sides. If the difference in MMD exceeds 1.0, the difference between the front and the back will increase, and the feeling of use will be different.
Moreover, as for the sanitary thin paper X1 of this form, it is desirable for the average deviation MMD of the friction coefficient of the surface in which the embossing convex part is formed to be 7-11. When 11 is exceeded, roughness becomes noticeable.
For the measurement of MMD, for example, “Friction Tester KESSE” manufactured by Kato Tech Co., Ltd. can be used. At the time of measurement, as shown in FIG. 3, a friction element consisting of a piano wire having a cross-sectional diameter of 0.5 mm and a contact surface length of 5 mm is moved while contacting a paper sample with a contact pressure of 10 g. The coefficient of friction is measured when the paper sample is moved 2 cm at a speed of 0.1 cm / sec while applying a tension of 20 g / cm to the paper sample. That is, the average deviation MMD of the friction coefficient is a value obtained by dividing the area of the variation amount of the surface thickness when the friction element is moved by the movement distance (2 cm). MMD generally has a correlation with smoothness.

  In addition, the sanitary thin paper X1 of this embodiment has a longitudinal strength (MDT) of 100 to 800 gf / 25 mm and a lateral strength (CDT) of 70 to 400 gf / 25 mm, particularly in the case of pop-up tissue paper. (MDS) is preferably 5 to 30% (measurement conforms to JIS P8113). The vertical and horizontal strengths are values per unit sheet of the product regardless of the number of plies. Below these lower limits, sheet breakage or the like tends to occur, and above the upper limits, the texture deteriorates. Further, when the elongation is below these lower limit values, sheet breakage or the like occurs, and when the elongation is higher than the upper limit value, wrinkles or the like occur in the sheet and the operability deteriorates.

Here, in the present invention, the raw material of the sanitary thin paper is not particularly limited. Depending on the application of the sanitary thin paper X1, appropriate raw materials such as pulp fibers, films of polyethylene, polyethylene terephthalate, polypropylene, and the like can be used.
Specifically, when the raw material is a pulp fiber, the pulp fiber (raw pulp) may be wood pulp, non-wood pulp, synthetic pulp, waste paper pulp, or the like, more specifically, groundwood pulp (GP). , Stone Grand Pulp (SGP), Refiner Grand Pulp (RGP), Pressurized Ground Pulp (PGW), Thermomechanical Pulp (TMP), Chemi Thermomechanical Pulp (CTMP), Bleach Chemi Thermomechanical Pulp (BCTMP) (MP), chemical mechanical pulp (CGP), semi-chemical pulp (SCP), hardwood bleached kraft pulp (LBKP), kraft pulp (KP) such as softwood bleached kraft pulp (NBKP), soda pulp (AP), monkey Chemical pulp (CP) such as fight pulp (SP), dissolving pulp (DP), Synthetic pulp made from Iron, rayon, polyester, polyvinyl alcohol (PVA), etc., waste paper pulp such as deinked pulp (DIP), waist pulp (WP), ground pulp (TP), cotton, flax, hemp, jute, One or several types of rag pulp, straw pulp, esparto pulp, bagasse pulp, bamboo pulp, kenaf pulp and other auxiliary pulps such as bast pulp, etc. can do.

The raw material consisting of pulp fibers, for example, is a known papermaking process, specifically, a sanitary thin paper that is subject to embossing through a wire part, a press part, a dryer part, a size press, a calendar part, etc. To do.
In this papermaking, for example, suitable chemicals such as a dispersant, caustic soda, aqueous ammonia and other pH adjusters, antifoaming agents, preservatives, fluorescent dyes, mold release agents, water resistance agents, flow modifiers, yield improvers, etc. Can be added.

[Method for producing sanitary thin paper having emboss]
Subsequently, the manufacturing method of the sanitary thin paper which has the embossing of this invention is further demonstrated, referring drawings. FIG. 4 is a diagram for explaining the embossing roll of the present invention, and FIG. 5 is a diagram for explaining the unit embossing convex portion of the present invention.
As described above, the raw material of the sanitary thin paper X1 used in the present invention and the papermaking method are not particularly limited. Therefore, here, a characteristic embossing method will be described.

The sanitary thin paper Y1 to which embossing is applied (hereinafter referred to as processed sanitary thin paper) has a paper thickness of 70 to 70 to obtain sufficient strength and the above-mentioned suitable embossed pattern and to prevent troubles during embossing. The thing of 300 micrometers and a basic weight of 10-40 g / m < ² > is used.
In this embodiment, as a suitable example, embossing is applied to a 2-ply sanitary thin paper sheet Y1 having a thickness of 80 to 200 μm in which two sanitary thin paper sheets having a basis weight of 10 to 15 g / m ² are stacked. Give.
In addition, it is good to measure the paper thickness of a sanitary thin paper to be processed using a peacock having a probe diameter of 10 mm (for example, G type manufactured by Ozaki Mfg. Co., Ltd.).
As shown in FIG. 4, the embossing is performed by passing the processed sanitary thin paper Y1 between a pair of embossing rolls composed of a nip roll 30 and an embossing roll 40 having an embossed pattern, and passing the embossed pattern to the processed sanitary thin paper. Press and apply to Y1.

In the present invention, as shown in FIG. 5, characteristically, the shape of each unit embossing convex portion 4 constituting the embossing pattern is such that the area of the top surface portion 4t is 0.3 to 1.8 mm ² and the taper angle. A unit embossing convex portion 4 having a solid shape in which the top edge of the truncated cone having θ of 20 to 50 degrees and a height 4 h of 0.3 to 1.5 mm is chamfered. In addition, the unit embossing convex part 4 can also employ an elliptical truncated cone having a chamfered top edge, a normal truncated cone having a chamfered top edge, and an elliptical truncated cone. A preferable example is a solid shape in which the top edge of the truncated cone in the illustrated example is chamfered. In FIG. 5, the chamfered portion is indicated by reference numeral 4r. When the top edge is chamfered, no edge is formed on the embossed convex portion to be applied, and a similar hemispherical embossed convex portion is formed. Thereby, the expressiveness of the smoothness of the embossing convex part formation surface improves. The radius of curvature R of the chamfered portion 4r is preferably 0.1 to 0.8. Further, the area of the top surface portion in the case of the chamfered shape is the area of the top surface before chamfering.

If the shape of the unit embossing convex portion 4 is made in this way, the shape of the unit embossing 1 formed on the sanitary thin paper becomes similar hemispherical due to the physical properties of the above-described sanitary thin paper Y1 to be processed and the embossing conditions described later. As a result, there is no feeling of roughness and there is little difference between the front and the back.
Furthermore, the sanitary thin paper X1 having the unit emboss 1 is excellent in smoothness of the surface, and even when used for a tissue paper product taken out in a pop-up format, the generation of paper dust at the time of taking out can be suitably used.

On the other hand, the embossing pattern is a pattern in which the unit embossing convex portions 4 are drawn by a straight or curved embossing convex row 4L arranged in parallel at intervals of 1.0 to 3.0 mm (D2 in the figure). Thereby, the embossed pattern which is excellent in the design property of the said description can be provided. Conventionally, this type of embossed pattern has been easy to feel rough, but the sanitary thin paper X1 obtained by the present invention has very little such rough feeling.
Moreover, as for the said embossing roll 40, it is good that the total area of an embossing provision convex part is 3 to 30% of an embossing roll surface. When such an embossing roll 40 is used, the embossed portion is clearly visually recognized with respect to the non-embossed portion, and a sanitary thin paper with a clear embossed pattern is obtained.
Further, it is desirable that the length of the straight line or curved line by the embossed convex part row is 10 mm or more, and the distance between the straight lines or the curved lines is 1 to 15 mm. In this way, an embossed pattern that is easily visible can be obtained.

Here, the nip roll 30 is preferably an elastic nip roll having at least a surface made of an elastic member such as rubber, and the embossing roll 40 is preferably made of resin. However, metal ones can also be used.
When using an elastic nip roll, it is preferable that the surface has a Shore hardness of 40 to 60 degrees. If the Shore hardness is too low, that is, if the elastic roll surface is too soft, the sheet or the sheet fabric may be broken. On the other hand, if the Shore hardness is too high, that is, if the surface of the elastic roll is too hard, there is a possibility that embossing does not enter.
The nip pressure (also referred to as embossing pressure or linear pressure) for embossing is 5-30 kgf / cm, preferably 10-25 kgf / cm. If the nip pressure is too low, the effect that the emboss becomes clear may not be sufficiently exhibited. On the other hand, if the embossing pressure is too high, the processed sanitary thin paper may be torn off.

As described above, the embossed sanitary thin paper is wound around a long paper tube and then used as a narrow toilet paper roll or led to an inter-holder to be a product such as tissue paper.
Although the present invention is extremely suitable for the single embossed form described above, the present invention is not limited to single embossed because it has an embossed convex part on one side, for example, embossed on each side. The present invention can also be applied to a form having an embossed concave portion corresponding to an embossed convex portion opposite to the convex portion.

About Example 1, 2 of this invention and Comparative Examples 1-4, it measured and evaluated about MMD, the touch feeling, and the clarity of embossing.
In addition, each example differs in the taper angle of the unit emboss provision convex part in the emboss roll used for emboss provision, and the area of a top surface part.
All other configurations were the same, the height of the unit embossing convex portions was all 1.0 mm, and the shape was a truncated cone. Further, the sanitary thin paper to be processed was 2 ply and had a basis weight of 22 g / m ² and a paper thickness of 110 μm, and the embossed pattern given to each example was the same. The embossing was single embossing.
Table 1 below shows the taper angle, the area of the top surface, and the evaluation of each example. The evaluation method is as follows.
[MMD]
Measurement was carried out according to the method described above using “Friction Tester KESSE” manufactured by Kato Tech Co., Ltd.
[Feel]
A sensory evaluation of 15 people was made. An example of 8 or more subjects who felt that the touch was good was evaluated as ◯, and an example of less than 8 subjects was evaluated as ×.
[Clarity of embossing]
A sensory evaluation of 15 people was made. An example of 8 or more subjects who felt that the embossing was clear was evaluated as ○, and an example of less than 8 was evaluated as ×.

  As is clear from the results shown in the table, the examples of the present invention were evaluated to be clear in the embossing and excellent in the touch feeling on the surface having the embossed protrusions. On the other hand, about the comparative example, evaluation that it was inferior in either a touch feeling or the clarity of embossing was obtained. Thus, as a result of evaluation, it can be said that the effect about the sanitary thin paper which has the embossing which concerns on this invention was shown.

  The present invention can be used for sheet products made of sanitary thin paper such as kitchen paper, toilet paper, and toilet roll as well as tissue paper.

It is a top view of the example of the sanitary thin paper of this invention. It is the II-II sectional view. It is a figure which shows the measuring apparatus of MMD. It is a figure for demonstrating the embossing roll which concerns on this invention. It is a figure for demonstrating the unit emboss provision convex part of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Unit embossing, 1L ... Embossing row | line | column, 10 ... Embossing, 11 ... Embossing convex part, 12 ... Embossing recessed part, 30 ... Nip roll, 40 ... Embossing roll, 4 ... Unit embossing convex part, 4t ... Unit embossing convex part Top surface portion, 4h: Unit embossing convex portion, 4r: Chamfered portion of embossing convex portion, θ: Taper angle of unit embossing convex portion, D1: Distance between embossed rows, T1: Paper thickness of non-embossed portion , T2 ... paper thickness of the embossed part, X1 ... sanitary thin paper with emboss, Y1 ... processed sanitary thin paper.

Claims (8)

Sanitary thin paper with embossing,
Unit emboss having a circular or elliptical shape in plan view has a pattern drawn by a straight or curved emboss row formed in parallel at intervals of 1.0 to 3.0 mm,
A part or all of the unit emboss forms an embossed convex portion on one surface,
And the difference of the paper thickness of a non-embossed part and an embossed part is 50-500 micrometers, The difference of the average deviation MMD of the friction coefficient of the surface in which the said embossing convex part is formed, and the surface in which an embossing recessed part is formed is A sanitary thin paper provided with embossing characterized by being 1.0 or less.   The sanitary thin paper according to claim 1, wherein the total area of the embossed portion is 3 to 30%.   The sanitary thin paper according to claim 1 or 2, wherein the extended length of the embossed rows is 10 mm or more, and the distance between the embossed rows is 1 to 10 mm. A truncated cone having a top surface area of 0.3 to 1.8 mm ² , a taper angle of 20 to 50 degrees, and a height of 0.3 to 1.5 mm, an elliptic frustum, or a solid in which these top edges are chamfered Between a pair of embossing rolls composed of an embossing roll having an embossing pattern composed of unit embossing convex portions and a nip roll, a paper thickness of 70 to 300 μm under a nip pressure of 5 to 30 kg / cm, the basis weight 10~40g produced through / m ² of the sanitary thin paper, sanitary thin paper according to any one of claims 1 to 3. A method for producing a sanitary thin paper having an emboss for forming an emboss on a sanitary thin paper through a sanitary thin paper between a pair of embossing rolls composed of a nip roll and an embossing roll having an embossing pattern,
The sanitary thin paper has a paper thickness of 70 to 300 μm and a basis weight of 10 to 40 g / m ² .
The unit embossing convex portion constituting the embossing pattern is a truncated cone having a top surface area of 0.3 to 1.8 mm ² , a taper angle of 20 to 50 degrees, and a height of 0.3 to 1.5 mm, Oval frustum or a solid unit embossing convex part with chamfered top edges thereof,
The nip pressure between the embossing rolls is 5 to 30 kg / cm.
The manufacturing method of the sanitary thin paper characterized by the above-mentioned.   6. The sanitary thin paper manufacture according to claim 5, wherein the embossing pattern is a pattern in which unit embossing projections are drawn in a line of straight or curved embossing projections arranged in parallel at intervals of 1.0 to 3.0 mm. Method.   The said embossing roll is a manufacturing method of the sanitary thin paper of Claim 5 or 6 whose total area of an embossing provision convex part is 3 to 30% of an embossing provision roll surface.   The sanitary thin paper according to any one of claims 5 to 7, wherein the length of the straight line or the curved line by the embossed convex part row is 10 mm or more, and the distance between the straight lines or the curved lines is 1 to 10 mm. Production method.

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