Wet tissue product and wet tissue package

Abstract

To provide a wet tissue product and a wet tissue package that are thick and durable, have an excellent folded appearance, and are also excellent in processability, productivity, and wiping performance.SOLUTION: Provided is a wet tissue product, in which a nonwoven fabric sheet composed of a composite nonwoven fabric obtained by hydroentangling a spunbond nonwoven fabric and a cellulose fiber web is folded and impregnated with a chemical liquid. The load required to stretch the nonwoven fabric sheet in a wetted state due to the impregnation with the chemical liquid by 5% in the CD direction is from 0.090 MPa to 1.000 MPa inclusive. The water absorbency (measured by the Byreck method) of the nonwoven fabric sheet in the absolutely dry state, in which no chemical liquid is impregnated, is from 55 mm to 170 mm inclusive in both the longitudinal and lateral directions.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to wet tissue products and wet tissue packages.

Background Art

[0002] Spunlace nonwoven fabric, which is formed by entangling pulp or regenerated cellulose fibers with synthetic fiber nonwoven fabric (hydroentangling), has higher wet strength than paper and has liquid absorption characteristics equivalent to those of paper, and is used in industrial applications and ordinary households. In industrial applications, there are products in the form of a roll with perforations, a four-fold product, a two-fold product, etc. as wiper products.

[0003] A form similar to tissue paper, in which a sheet that can also be used in ordinary households pops up for use, is one of the forms that are easy for users to use, and an increase in the usage amount in the future is expected.

[0004] For example, Patent Document 1 discloses a wet tissue using a composite nonwoven fabric obtained by hydroentangling a spunbond nonwoven fabric and a pulp fiber web as a base fabric. By specifying the basis weight and mass composition ratio of the pulp fiber web and the spunbond nonwoven fabric, the fiber diameter of the spunbond nonwoven fabric, the elongation rate when a load is applied, and further the abrasion resistance in the wet Taber test, the manufacturing cost is suppressed, and not only the water retention and wet strength but also the appearance, texture, wiping property, etc. are improved.

[0005] Further, Patent Document 2 discloses a nonwoven fabric wiper package in which a spunlace nonwoven fabric sheet is laminated by a multi-folder type folding machine, cut into a predetermined size, and stored in a storage container. By specifying the blending ratio of pulp or rayon in the sheet, the basis weight of the sheet, the rigidity and strength of the sheet, etc., it is possible to improve productivity, prevent extractability, texture, folding wrinkles, and cutting defects.

[0006] However, in the case of conventional laminated wet tissues, when attempting to manufacture a thick one to improve the usability such as ease of wiping, it was difficult to achieve both liquid absorbency and processability. In the laminated type, the base fabric is unwound from the base fabric roll and processed through several folding processes such as C-folding, longitudinal folding, or double folding using a folding machine. However, wrinkles are likely to occur during these folding processes. This tendency was particularly prominent in thick tissues. Therefore, there has been a demand for a wet tissue that is suitable for folding even when thick.

[0007] In addition, while an improvement in the water absorbency of wet tissues can be expected to improve the production speed by quickly absorbing the chemical solution during chemical solution impregnation, if the longitudinal and lateral sheet elongation is adjusted to suppress wrinkles during folding, the wiping property may deteriorate.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0009] Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a wet tissue product and a wet tissue package that are thick, durable, have a good appearance of folds, and also have good processability, productivity, and wiping property.

Means for Solving the Problems

[0010] The inventor conducted intensive studies and found that the above problems can be solved by defining the load required to stretch the nonwoven sheet, which is composed of a composite nonwoven fabric obtained by water entanglement of a spunbond nonwoven fabric and a cellulose fiber web, folded, and impregnated with a chemical solution, by 5% in the CD direction when it is in a wet state due to the impregnation of the chemical solution, and the water absorbency (Birek method) of the nonwoven sheet in a completely dry state without the chemical solution impregnation, thus completing the present invention. That is, the present invention provides the following.

[0011] (1) The first aspect of the present invention is a wet tissue product in which a nonwoven sheet made of a composite nonwoven fabric obtained by water entanglement of a spunbond nonwoven fabric and a cellulose fiber web is folded and impregnated with a chemical solution, wherein the load required to stretch the nonwoven sheet in the CD direction by 5% when it is in a wet state due to the impregnation of the chemical solution is 0.090 MPa or more and 1.000 MPa or less, and the water absorbency (Birek method) of the nonwoven sheet in a completely dry state without the chemical solution impregnation is 55 mm or more and 170 mm or less in both the longitudinal and transverse directions.

[0012] (2) The second aspect of the present invention is the wet tissue product according to (1), characterized in that the water absorbency (Birek method) of the nonwoven sheet in a completely dry state is 60 mm or more and 160 mm or less in both the longitudinal and transverse directions.

[0013] (3) The third aspect of the present invention is the wet tissue product according to (1), wherein the cellulose fiber contained in the cellulose fiber web is a pulp fiber, and the basis weight of the nonwoven sheet in a completely dry state is 60 g / m 2 or more and 150 g / m 2 or less.

[0014] (4) The fourth aspect of the present invention is the wet tissue product described in (1), wherein in the non-woven fabric sheet in a wet state, the ratio of the load required to stretch 5% in the MD direction to the load required to stretch 5% in the CD direction is 4.0 or more and 10.0 or less.

[0015] (5) The fifth aspect of the present invention is the wet tissue product described in (1), wherein the folding method of the non-woven fabric sheet is to at least C-fold the non-woven fabric sheet, then half-fold it in a direction parallel to the C-folded direction, and then half-fold it in a direction perpendicular to the C-folded direction.

[0016] (6) The sixth aspect of the present invention is the wet tissue product described in (5), wherein the direction of C-folding the non-woven fabric sheet is the MD direction.

[0017] (7) The seventh aspect of the present invention is a wet tissue package having the wet tissue product described in (1) and a film packaging bag for storing the wet tissue product.

Advantages of the Invention

[0018] According to the present invention, it is possible to provide a wet tissue product and a wet tissue package that are thick, strong, have a good folding appearance, and also have good processing suitability, productivity, and wiping properties.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Modes for Carrying Out the Invention

[0020] Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as embodiments) will be described in detail with reference to the drawings as appropriate. However, these are presented for illustrative purposes and do not limit the present invention.

[0021] In this specification, the non-woven fabric sheet means a single sheet cut out from the raw material of the composite non-woven fabric. A wet tissue product (hereinafter also simply referred to as "wet tissue") means a non-woven fabric sheet folded and impregnated with a chemical solution during the process. And the wet tissue package means a wet tissue product packaged in a packaging bag made of film or the like. Also, the MD direction and the CD direction respectively mean the manufacturing line direction (conveying direction) and the direction orthogonal to the manufacturing line direction during the manufacture of the wet tissue raw material.

[0022] [Composite non-woven fabric] The non-woven fabric serving as the base material of the wet tissue product 1 of the present invention is a composite non-woven fabric. The composite non-woven fabric is formed by entangling staple-bonded non-woven fabric and cellulose fiber web with each other by high-pressure water flow.

[0023] The process of the composite non-woven fabric is not particularly limited as long as it is a general non-woven fabric manufacturing method, but it preferably includes mainly (1-1) a process of manufacturing a web, (1-2) a process of three-dimensionally entangling fibers, (1-3) a process of removing (drying) moisture, and the like.

[0024] [Staple-bonded non-woven fabric] The staple-bonded non-woven fabric used as the material of the composite non-woven fabric can be selected from, for example, nylon, vinylon, polyester, acrylic, polyethylene, polypropylene, polystyrene, etc. as synthetic resin fibers, and is a non-woven fabric sheet formed by the dry staple-bonding method. The staple-bonded non-woven fabric functions to reinforce the non-woven fabric sheet and maintain the outer shape.

[0025] [Cellulose fiber web] As the cellulose fibers contained in the cellulose fiber web used as the material of the composite nonwoven fabric, those based on natural fibers such as pulp and cotton can be adopted. Among them, pulp fibers are preferable from the viewpoints of less foreign matter content and liquid absorbency during production. For example, when adopting wood pulp, NBKP such as radiata pine, slash pine, southern pine, spruce, Douglas fir, etc. is preferable as the wood species, and it may be appropriately selected in consideration of fibrillation property, yield, etc. As the regenerated cellulose fiber, rayon etc. can be preferably used. The cellulose fiber web functions to improve the water absorbency and texture of the nonwoven fabric sheet.

[0026] When integrating the spunbond nonwoven fabric and the cellulose fiber web by hydroentanglement, a conventionally known hydroentanglement technique can be used, and such a technique is described in detail in Patent Document 2, for example.

[0027] The composite nonwoven fabric wound around the parent roll is continuously folded and cut while feeding out the parent roll (composite nonwoven fabric) from the parent roll, thereby producing a wet tissue folding form as shown in FIG. 2. After impregnating with the chemical solution during the process of manufacturing the folding form, it is packaged in the packaging bag 20 as shown in FIG. 1 to become the wet tissue package 2.

[0028] (Folding of the nonwoven fabric sheet) The nonwoven fabric sheet 10 is folded by combining C-fold, Z-fold, V-fold, half-fold, etc. according to the application. For example, as shown in FIG. 2, the nonwoven fabric sheet 10 (state X0 in FIG. 2) is C-folded in at least one direction, for example, a direction parallel to the long side direction (state X1 in FIG. 2), and further half-folded in a direction parallel to the C-fold direction (state X2 in FIG. 2), and then half-folded in a direction orthogonal to the C-fold direction (state X3 in FIG. 2). Here, it is more preferable that the C-fold direction is the MD direction. With this folding method, the number of portions where the cut surface is exposed is reduced, resulting in good skin feel.

[0029] (Impregnation with chemical solution) The non-woven fabric sheet 10 is impregnated with a chemical solution and formed into the wet tissue 1 after being folded and before being stored in the storage bag 20. The chemical solution impregnated in the non-woven fabric sheet 10 may be formulated with alcohol, moisturizer, preservative, antibacterial agent, stabilizer, etc. that are usually used in wet tissues. Note that it is preferably ethanol-free from the viewpoint of irritation to the skin.

[0030] (Impregnation ratio of chemical solution) The lower limit of the impregnation ratio of the chemical solution into the non-woven fabric sheet 10 is preferably 150% or more, more preferably 200% or more. The upper limit is preferably 320% or less, more preferably 300% or less. If the impregnation ratio is less than 150%, the chemical solution will volatilize before using up one wet tissue 1, resulting in less wet feeling and poor texture of the wet tissue 1. If the impregnation ratio exceeds 320%, the chemical solution impregnated in the wet tissue 1 will be squeezed out and the chemical solution will remain inside the packaging bag 20 after use.

[0031] The method for measuring the impregnation ratio is as follows: First, measure the area and weight of the wet tissue 1, then wash the wet tissue 1 with an alcohol solution and dry it completely. After complete drying, condition it in an environment of 23°C and 50% RH, and measure the weight of the wet tissue 1. Then, obtain the weight of the chemical solution impregnated per 1 g of the wet tissue 1 as a percentage, which is defined as the impregnation ratio.

[0032] [Wet tissue package] As shown in FIG. 1, the wet tissue 1 is stored in the packaging bag 20 to form the wet tissue package 2. The packaging bag 20 may be provided with an outlet for the wet tissue 1 (not shown). The packaging bag 20 can be a paper carton or a polyethylene pack (film packaging), but film packaging is preferred from the viewpoints of ease of processing and convenience as an individual package.

[0033] [Physical properties of non-woven fabric sheet] (Grammage in absolutely dry state) The lower limit of the grammage of the non-woven fabric sheet 10 in the absolutely dry state is preferably 60 g / m 2 or more, preferably 62 g / m2 The above is more preferable, and 63 g / m 2 The above is even more preferable. The lower limit value is 150 g / m 2 The following is preferable, and 140 g / m 2 The following is more preferable, and 130 g / m 2 The following is even more preferable. When the basis weight is less than 60 g / m 2 , the thickness as the wet tissue 1 is insufficient, and it is easy to have holes during wiping, and the strength as a wiper is inferior. When the basis weight exceeds 150 g / m 2 , the non-woven fabric sheet 10 becomes rigid and the sheet is likely to open during folding, so the processing suitability is inferior. The basis weight of the non-woven fabric sheet 10 can be measured in accordance with JIS P 8124 after conditioning the wet tissue 1 under the conditions of 23°C and 50%.

[0034] (Required load when stretching 5% in the CD direction in the wet state) The required load when stretching the non-woven fabric sheet 10 by 5% in the CD direction in the wet state is 0.090 MPa or more and 1.000 MPa or less. When the required load is less than 0.090 MPa, the non-woven fabric sheet 10 is likely to stretch even with a small tension and is likely to have folding displacement, so the suitability during folding is inferior. When it exceeds 1.000 MPa, the adjustment cost when tension is applied to the non-woven fabric sheet 10 is small and wrinkles are likely to occur, so the suitability during folding is inferior. The measurement method is to measure the load for 5% elongation when a non-woven fabric sheet 10 with a width of 25 mm is impregnated with pure water, then gently remove the moisture, and pull it with a tensilon at a speed of 20 mm / min in the CD direction.

[0035] (MD / CD ratio of required load when stretching 5% in the wet state) When stretching the nonwoven fabric sheet 10 in the wet state by 5%, the lower limit value of the MD / CD ratio of the load required is preferably 4.0 or more, more preferably 5.0 or more, and still more preferably 6.0 or more. The upper limit value is preferably 10.0 or less, more preferably 9.0 or less, and still more preferably 8.0 or less. If the MD / CD ratio is less than 4.0, the CD direction (lateral direction) is less likely to stretch relative to the MD direction (longitudinal direction), resulting in inferior flexibility during processing with folding plates and easy wrinkling. If the MD / CD ratio exceeds 10.0, the CD direction (lateral direction) is more likely to stretch relative to the MD direction (longitudinal direction), making it easy to have width expansion in the CD direction and resulting in inferior dimensional stability. Note that the measurement method of the load required when stretching the nonwoven fabric sheet 10 in the wet state by 5% in the MD direction conforms to the above-described measurement method for the CD direction (with the load direction being the MD direction).

[0036] (Water absorption in the bone-dry state (Birek method)) The water absorption of the nonwoven fabric sheet 10 in the bone-dry state by the Birek method is 55 mm or more and 170 mm or less in both the longitudinal and lateral directions. The lower limit value of the water absorption is preferably 60 mm or more, more preferably 70 mm or more. The upper limit value is preferably 160 mm or less, more preferably 130 mm or less. If the water absorption is less than 55 mm, the liquid absorption during production is inferior, resulting in a decrease in production efficiency. On the other hand, if it exceeds 170 mm, the nonwoven fabric sheet 10 is likely to slip during folding processing, leading to a decrease in production efficiency.

[0037] The water absorption is measured by the Birek method of JIS L 1907. First, five test pieces of 200 mm × 25 mm are collected from the nonwoven fabric sheet 10 in the MD direction (longitudinal direction) and the CD direction (lateral direction) respectively, and conditioned under the conditions of 23°C and 50%. After conditioning, the test pieces are fixed with pins or the like on a horizontal bar supported on the water surface of a water tank filled with pure water (water temperature 20 ± 2°C), and then the horizontal bar is lowered so that the lower end of the test piece is immersed in the pure water by 20 ± 2 mm, and left for 10 minutes. After leaving, the height to which the water has risen is measured in 1 mm units using a scale. The test results are represented by rounding the average value of the height to which the water has risen five times for the test pieces in the MD direction (longitudinal direction) and the CD direction (lateral direction) to an integer (mm).

Examples

[0038] Hereinafter, the present invention will be described in detail with reference to examples. Note that the present invention is not limited to the examples shown below.

[0039] <Examples 1 to 5, Comparative Examples 1 to 3> Nonwoven sheets and wet tissues were produced based on each condition shown in Table 1, and the following evaluations were performed.

[0040] 1. Suitability during folding during manufacturing The nonwoven sheet was put into the production line, and the suitability during folding (folding processability, appearance of the fold, and degree of wrinkling) was evaluated in the following two levels. ri ◎: There is no problem with the folding processability, the appearance of the fold of the sheet is good, and there are no wrinkles. ×: Any one of the folding processability, the appearance of the fold of the sheet, and the wrinkling is inferior.

[0041] 2. Liquid absorbency during manufacturing (production efficiency) The water absorbency in the longitudinal and transverse directions of the nonwoven sheet in a bone-dry state was measured by the Birex method, and the average value of the measured values in the MD direction (longitudinal direction) and the CD direction (transverse direction) was calculated and evaluated in the following three levels. ◎: 60 mm or more and less than 160 mm ○: 50 mm or more and less than 60 mm, or 160 mm or more ×: Less than 50 mm

[0042] 3. Wiping property of the wet tissue Ten monitors evaluated the wiping property of the wet tissue product in the following three levels. ◎: The number of people who answered that the wiping property is poor is less than 2. ○: The number of people who answered that the wiping property is poor is 2 to 4. ×: The number of people who answered that the wiping property is poor is 5 or more.

[0043] 4. Strength of the wet tissue The wet tissue was subjected to the wet taber test specified in JIS, the wet taber value (number of times) was measured, and it was evaluated in the following three levels. ◎: Wet Taber value is 100 times or more ○: Wet Taber value is 20 times or more and less than 100 times ×: Wet Taber value is less than 20 times

[0044] 4. Comprehensive Evaluation Based on the evaluation results of the above 1 to 3, the evaluation was carried out in the following 4 levels. 4 points: All evaluation results are ◎ 3 points: There are 3 items with an evaluation result of ◎ and no evaluation result of × 2 points: There are 2 items with an evaluation result of ◎ and no evaluation result of × 1 point: There is one or more evaluation results of ×

[0045] Table 1 shows the conditions and evaluation results of each example and comparative example.

[0046]

Table 1

[0047] As shown in Table 1, according to this example, it was confirmed that a wet tissue product that is thick and strong, has a good appearance after folding, and also has good processability, productivity, and wiping property can be obtained.

Explanation of Signs

[0048] 1 Wet Tissue (Product) 10 Non-woven Fabric Sheet X0 State before folding the non-woven fabric sheet X1 State where the non-woven fabric sheet is C-folded X2 State where the non-woven fabric sheet is half-folded after C-folding X3 State where the non-woven fabric sheet is further half-folded after C-folding and half-folding 2 Wet Tissue Package 20 Packaging Bag

Claims

1. A wet tissue product obtained by folding a non-woven fabric sheet made of a composite non-woven fabric obtained by hydroentangling a spunbond non-woven fabric and a cellulose fiber web and impregnating it with a chemical solution, wherein the load required to stretch the non-woven fabric sheet in the wet state by 5% in the CD direction due to the impregnation of the chemical solution is 0.090 MPa or more and 1.000 MPa or less, and the water absorbency (Bylek method) of the non-woven fabric sheet in the absolutely dry state without the chemical solution impregnation is 55 mm or more and 170 mm or less in both the longitudinal and transverse directions characterizes the wet tissue product.

2. The wet tissue product according to Claim 1, wherein the water absorbency (Bylek method) of the non-woven fabric sheet in the absolutely dry state is 60 mm or more and 160 mm or less in both the longitudinal and transverse directions.

3. The cellulose fiber contained in the cellulose fiber web is pulp fiber, The nonwoven fabric sheet has a basis weight of 60 g / m2 in an absolutely dry state. ２ 150g / m or more ２ 2. The wet tissue product according to claim 1, characterized in that:

4. The wet tissue product according to Claim 1, wherein in the wet non-woven fabric sheet, the ratio of the load required to stretch by 5% in the MD direction to the load required to stretch by 5% in the CD direction is 4.0 or more and 10.0 or less.

5. The wet tissue product according to Claim 1, wherein the folding method of the non-woven fabric sheet is at least C-fold the non-woven fabric sheet, then half-fold it in a direction parallel to the C-folded direction, and then half-fold it in a direction perpendicular to the C-folded direction.

6. The wet tissue product according to Claim 5, wherein the direction of C-folding the non-woven fabric sheet is the MD direction.

7. A wet tissue package having the wet tissue product according to Claim 1 and a film packaging bag for storing the wet tissue product.

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