Pulp-containing non-woven wipe

Abstract

To provide a pulp-containing non-woven wipe which has excellent liquid absorption and strength, and in particular, exhibits little decrease in strength when wet.SOLUTION: The problem is solved by a pulp-containing non-woven wipe obtained by entangling pulp fibers 10 and regenerated cellulose fibers, the pulp-containing non-woven wipe having a basis weight of 30-90 g / m2, and the regenerated cellulose fibers being lyocell 20.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a pulp-mixed nonwoven wipe. [Background technology]

[0002] Pulp-mixed nonwoven wipes are known that are made by integrating pulp fibers with other fibers. Conventional pulp-mixed nonwoven wipes are made by integrating hydrophilic pulp fibers with synthetic fibers derived from petroleum, such as high-strength polypropylene, into a sheet shape, and thus achieve both water and oil absorbency and strength. These pulp-mixed nonwoven wipes are highly versatile due to their compatibility with liquid absorbency and strength, and are used for various purposes such as cleaning production lines, kitchen counters, machines, filling machines, and facilities, wiping off dirt, and wiping hands at cooking and manufacturing sites (Patent Document 1, Patent Document 2, etc. below).

[0003] As a specific example of a conventional pulp-mixed nonwoven wipe, for example, Patent Document 1 below discloses a pulp-mixed nonwoven wipe in which pulp fibers are integrated with a spunbonded nonwoven fabric of synthetic fibers such as polypropylene. Patent Document 2 discloses a pulp-mixed nonwoven wipe in which a web containing pulp fibers, recycled fibers, and composite synthetic fibers is integrated with a spunbonded nonwoven fabric of synthetic fibers such as polypropylene by hydroentanglement. The pulp-mixed nonwoven wipes in which pulp fibers are integrated with a spunbonded nonwoven fabric made of synthetic resin disclosed in Patent Documents 1 and 2 have sufficiently high water absorbency and strength, particularly strength when wet.

[0004] On the other hand, in recent years, the problem of marine pollution caused by microplastics has attracted attention, and the use of plastic-free products in various products is progressing worldwide from the perspective of environmental considerations, etc. Conventional pulp-mixed nonwoven wipes contain more than 20% petroleum-derived synthetic fibers, and it is desirable to reduce the amount of petroleum-derived synthetic resin used in these pulp-mixed nonwoven wipes for environmental considerations. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-084385 A [Patent Document 2] JP 2019-039116 A [Patent Document 3] JP 2005-143523 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, simply decreasing the proportion of petroleum-derived synthetic fibers and increasing the proportion of pulp fibers reduces strength and makes some of the pulp fibers more likely to detach from the surface as lint. Pulp-mixed nonwoven wipes have techniques for increasing strength and preventing lint by applying binders or adhesives, but the application of binders, etc., has the drawback of reducing liquid absorbency and increasing costs.

[0007] As a wipe that does not use synthetic resin derived from petroleum, the above-mentioned Patent Document 3 discloses a wipe that uses only recycled fibers derived from natural products. However, this wipe is intended for low dust generation required in clean rooms such as those used by lens manufacturers and manufacturing sites of precision parts such as semiconductors, and does not have the strength or liquid absorbency required for general purposes such as cleaning equipment and facilities, wiping off dirt, and wiping hands in cooking and manufacturing sites, and is not suitable for general-purpose use.

[0008] Therefore, a main object of the present invention is to provide a pulp-mixed nonwoven fabric wipe that does not contain synthetic fibers derived from petroleum but has excellent liquid absorbency and strength in dry and wet conditions, and is versatile enough to be suitable for cleaning, wiping, wiping off dirt and liquids from food, objects, and living organisms such as the human body, etc. More preferably, the pulp-mixed nonwoven fabric wipe generates little lint and has excellent heat resistance. [Means for solving the problem]

[0009] The means for solving the problems of the present invention are as follows. That is, the first method is: A pulp-mixed nonwoven wipe in which pulp fibers and regenerated cellulose fibers are entangled, Basis weight: 30~90g / m 2 and The regenerated cellulose fiber is lyocell. The pulp-mixed nonwoven wipe is characterized by the above.

[0010] The second method is The pulp-mixed nonwoven fabric wipe according to the first aspect of the present invention has a blending ratio of pulp fiber and lyocell of 50:50 to 80:20.

[0011] The third method is The pulp-mixed nonwoven wipe according to the first or second aspect of the present invention has a fiber length of lyocell of 21 mm or more and 78 mm or less.

[0012] The fourth measure is The pulp-mixed nonwoven fabric wipe according to the first or second aspect, wherein the entanglement is achieved by hydroentanglement.

[0013] The fifth measure is: The pulp-mixed nonwoven fabric wipe according to the first or fifth aspect has protrusions formed at a pitch of 2 to 6 mm on at least one surface.

[0014] The sixth measure is: The pulp-mixed nonwoven fabric wipe according to the first or second aspect has a (wet tensile strength) / (dry tensile strength) ratio of 0.8 or more in both the machine direction and the cross direction. Effect of the Invention

[0015] According to the present invention, there is provided a pulp-mixed nonwoven fabric wipe that is excellent in liquid absorption and strength in dry and wet conditions even without containing synthetic fibers derived from petroleum, and has excellent versatility suitable for cleaning, wiping, wiping off dirt and liquids from food, objects, and living organisms such as the human body, etc. More preferably, the pulp-mixed nonwoven fabric wipe generates little lint and has excellent heat resistance. [Brief description of the drawings]

[0016] [Figure 1] 1 is an explanatory diagram of the protrusions of the pulp-mixed nonwoven fabric wipe of the present embodiment and a method for forming the protrusions. [Diagram 2] FIG. 2 is a plan view illustrating the convex portions of the pulp-mixed nonwoven fabric wipe of the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Next, embodiments of the present invention will be described in detail below with reference to the drawings. However, the present invention is not limited to these embodiments.

[0018] The pulp-mixed nonwoven wipe of this embodiment is a pulp-mixed nonwoven fabric in which pulp fibers and regenerated cellulose fibers are entangled. The basis weight is 30 to 90 g / m 2 and preferably 45 to 80 g / m 2 and more preferably 50 to 60 g / m 2 The basis weight is 30 to 90 g / m 2 If so, in combination with other configurations of the present invention, it is possible to obtain the liquid absorbency and strength required for general-purpose use. The basis weight is a value measured in accordance with JIS P 8124.

[0019] The thickness of the pulp-mixed nonwoven fabric wipe of the present embodiment is not necessarily limited, but is preferably 450 to 900 μm. Note that this thickness refers to a value measured based on JIS L 1913.

[0020] The total ratio of pulp fibers and regenerated cellulose fibers in the constituent fibers of the pulp-mixed nonwoven wipe of this embodiment is 95% or more. It is preferably 98% or more, and particularly preferably 100%. Since pulp fibers and regenerated cellulose fibers are fibers derived from natural products, if the total ratio of pulp fibers and regenerated cellulose fibers is 95% or more, it can be said that the wipe is sufficiently plastic-free compared to conventional pulp-mixed nonwoven wipes. Also, if it is 100%, it can be said that the wipe is plastic-free. When fibers other than pulp fibers and regenerated cellulose fibers are included, it is preferable that the fibers are natural fibers from the viewpoint of plastic-free. However, it can be said that plastic reduction has been sufficiently achieved even if synthetic fibers are included at 5% or less.

[0021] The regenerated cellulose fiber in the pulp-mixed nonwoven wipe of this embodiment is characteristically 100% Lyocell. Lyocell is not derived from petroleum raw materials like nylon and polyester, but is a natural fiber produced by a solvent spinning method using wood as a raw material. Lyocell is also sometimes called Tencel.

[0022] In the pulp-mixed nonwoven wipe of this embodiment, the regenerated cellulose fiber is 100% Lyocell, so that even if the blending ratio of synthetic fiber is 5% or less, especially 0%, the strength when dry is sufficient for general use. Furthermore, by using 100% Lyocell as the regenerated cellulose fiber, the strength when wet is also sufficient for general use. In other words, the nonwoven wipe of this embodiment has excellent strength when dry and when wet, and further has little or no change in strength from dry to wet and from wet to dry, so that it is easy to use in situations where both wiping off dry objects and wiping off liquids are required, and for applications where wiping is performed by soaking it in liquids such as water or liquid detergent.

[0023] In addition, lyocell is a regenerated cellulose fiber derived from wood and has excellent heat resistance. The melting points of polyethylene fibers and polypropylene fibers used in many conventional pulp-mixed nonwoven wipes are 170°C or less, so some conventional pulp-mixed nonwoven wipes are not particularly suitable for wiping off high-temperature oil, absorbing oil, or straining oil. In the pulp-mixed nonwoven fabric of this embodiment, if the fibers are 100% pulp fibers and lyocell, the heat resistance temperature can be 400°C or more. Therefore, the pulp-mixed nonwoven wipe can be used as cooking paper and oil-stiffening sheets in food factories, manufacturers of lunch boxes and prepared foods, and at home.

[0024] The fiber length of the lyocell in the pulp-mixed nonwoven wipe of this embodiment is preferably 21 mm to 78 mm, and more preferably 28 mm to 65 mm. Lyocell with a fiber length of 21 mm to 78 mm is easily entangled with pulp fibers, especially pulp fibers derived from conifers, resulting in a pulp-mixed nonwoven wipe that is particularly unlikely to generate lint. In addition, lyocell with a fiber length in this range can be suitably entangled with pulp fibers, especially pulp fibers derived from conifers, by hydroentanglement. Therefore, when the pulp-mixed nonwoven wipe of this embodiment is one in which pulp fibers and lyocell are entangled by hydroentanglement, the entanglement is suitably performed, and in combination with the effect of hydroentanglement described below, the entanglement is particularly unlikely to generate lint. The fiber length according to the present invention is the length-weighted average fiber length L(l) measured using a fiber length measuring device (Kajani / Fiber Lab, manufactured by Metso Automation) for disintegrated fibers after disintegration in accordance with JIS P 8220. When it is not possible or difficult to measure using this fiber length measuring device, the fiber can be observed under an electron microscope and contrastive measurements are made to determine the fiber length from the comparison results.

[0025] The fiber thickness of the lyocell in the pulp-mixed nonwoven wipe of this embodiment is not necessarily limited, but is preferably 0.8 dtex to 1.8 dtex, particularly preferably 1.0 dtex to 1.6 dtex. This fiber thickness tends to be firmly entangled with pulp fibers, particularly pulp fibers derived from conifers. The fiber thickness can be calculated from the specific gravity of the fiber, the thickness measured by observation under an electron microscope as in the previous section, and the cross-sectional shape.

[0026] The pulp fibers in the pulp-mixed nonwoven wipe of this embodiment can be selected from pulp fibers derived from broadleaf trees, pulp fibers derived from coniferous trees, and pulp fibers derived from waste paper. The average fiber length (hereinafter also referred to as the fiber length) is preferably 3.0 to 5.0 mm. It is easily entangled with lyocell. Among the above pulp fibers, pulp fibers derived from coniferous trees are particularly preferable. The pulp fibers derived from coniferous trees have an average fiber length of 3.5 to 4.0 mm and a fiber diameter of about 50 μm, and are easily entangled with lyocell, and are particularly unlikely to generate lint derived from pulp fibers. Specifically, they are bleached coniferous kraft pulp (NBKP) and unbleached coniferous pulp (NUKP). The pulp fibers preferably contain 95% by mass or more of this pulp fiber derived from coniferous trees. In particular, the pulp fibers are preferably 100% by mass of pulp fibers derived from coniferous trees. The average fiber length of this pulp fiber is the length-weighted average fiber length L(l) measured on the disintegrated fibers after disintegration in accordance with JIS P 8220 using a fiber length measuring device (Kayani / Fiber Lab, manufactured by Metso Automation).

[0027] The blending ratio of pulp fiber and lyocell in the pulp-mixed nonwoven wipe of this embodiment is not limited, and can be adjusted to pulp fiber:lyocell=10:90 to 90:10. The pulp fiber:lyocell ratio is preferably 50:50 to 80:20, and particularly preferably pulp fiber:lyocell=60:40 to 80:20. When the pulp fiber:lyocell ratio is 50:50 to 80:20, the liquid absorption property by the pulp fiber, the strength improvement in dry and wet conditions by the lyocell, and the suppression of lint generation are well balanced. The suppleness and softness are also good, and the pulp-mixed nonwoven wipe has excellent versatility.

[0028] On the other hand, the entanglement of the pulp fibers and the lyocell in the pulp-mixed nonwoven wipe of this embodiment is not necessarily limited, but is preferably performed by hydroentanglement (spunlace method). That is, the pulp-mixed nonwoven wipe of this embodiment is preferably a pulp-mixed nonwoven fabric by the spunlace method, also called a spunlace nonwoven fabric or a spunlace-type nonwoven fabric. If the entanglement of the pulp fibers and the lyocell is performed by hydroentanglement, fine pulp fibers fall off during production due to the water flow, so that the generation of lint is reduced. In addition, the pulp-mixed nonwoven wipe of this embodiment may have a fiber orientation in the thickness direction, such that one side is a pulp surface with an excess of pulp fibers and the other side is a regenerated cellulose surface with an excess of regenerated cellulose fibers, and the fiber type blend ratio may be different between the front and back sides. Of course, the fiber orientation may be uniform in the thickness direction.

[0029] Here, the particularly preferred hydroentanglement of the pulp-mixed nonwoven wipe of this embodiment is preferably carried out as follows. That is, as shown in FIG. 1, a pulp slurry is discharged onto the carded Lyocell fiber web 20 to laminate the pulp fibers 10 in a wet paper state, and then, in accordance with the spunlace technology also called water jet technology, water needle technology, etc., a water stream 30 is sprayed and struck against the pulp fiber surface of the laminated sheet in which the pulp fiber wet paper 10 and the Lyocell fiber web 20 are laminated, so that the pulp fibers of the wet paper 10 penetrate into the Lyocell fibers of the Lyocell fiber web 20 to hydroentangle. In this hydroentanglement, it is particularly preferable that the fiber length and fiber thickness of the pulp fibers and Lyocell fibers derived from the above-mentioned coniferous trees are the same. Note that the wet paper and the fiber web may be laminated in multiple layers, but it is preferable to laminate each layer in one layer.

[0030] In the hydroentanglement according to the present embodiment, the pulp fibers may be in the form of a thin paper produced by papermaking, or a dried pulp sheet produced by discharging a pulp solution in which pulp fibers are dispersed and suspended in water onto a conveying plane and compressing and drying the same in a heated drum to produce a sheet. The drying temperature of the dried pulp sheet is 85 to 115°C, preferably 90 to 110°C. When a dried pulp sheet is used, the fiber orientation in the length and width directions is small, and the aspect ratio difference of the dry tensile strength is small.

[0031] Furthermore, in the hydroentanglement according to the present embodiment, the nozzle diameter of the nozzle for spraying the water stream is preferably 0.5 to 1.5 mmφ, more preferably 0.75 to 1.25 mmφ. This nozzle diameter is smaller than that of the nozzle system used in the conventional spunlace method for pulp-mixed nonwoven wipes. The water pressure is not necessarily limited, but is preferably 350 to 450 bar, particularly preferably 380 to 420 bar. This water pressure is higher than the general water pressure (80 to 90 bar). By spraying a water stream at high pressure from a small-diameter nozzle against the pulp fibers, the pulp fibers and the lyocell fibers are well entangled, and in particular, the pulp fibers are well inserted into the lyocell fiber web surface side, making it difficult for the pulp fibers to separate from the front and back, and making it difficult for lint to occur. Note that pulp fibers derived from coniferous trees and lyocell with a fiber length of 21 mm or more and 78 mm or less are particularly suitably entangled in the spunlace method under these conditions.

[0032] The pulp-mixed nonwoven wipe of this embodiment is able to maintain the entanglement of the pulp fibers and lyocell and bond the fibers together by heat fusion using binder fibers such as binders, adhesives, and heat-sealing fibers. However, the application of heat-sealing fibers or binders tends to reduce liquid absorbency and increases costs. In particular, the use of heat-sealing fibers prevents a shift away from plastics. Therefore, it is desirable for the pulp-mixed nonwoven wipe of this embodiment to be free of binders, petroleum-derived synthetic fibers, and heat-sealed parts.

[0033] On the other hand, as shown in FIG. 2, the pulp-mixed nonwoven wipe of this embodiment is preferably formed with convex portions 60 arranged at a pitch L1 of 2 to 6 mm on at least one side. Concave portions corresponding to the convex portions may be formed on the opposite side of the convex portions. The convex portions 60 improve the wiping ability to scrape off dirt and increase the softness. The pitch L1 refers to the interval between the convex portions 60 regularly arranged in the machine direction (MD) and the direction perpendicular to the machine direction (CD). The minimum distance L2 between the convex portions 60 on the pitch is not necessarily limited, but is preferably 0.5 to 2.5 mm.

[0034] The protrusions 60 may be formed by embossing, but are preferably formed by hydroentanglement. When embossing is used, the bottoms of the recesses formed on the opposite sides of the protrusions are compacted, reducing the generation of lint. Furthermore, protrusions formed by hydroentanglement have planar fiber orientation, and fine pulp fibers fall off during entanglement, so that the generation of lint is particularly effectively reduced.

[0035] The formation of the convex portions 60 by hydroentanglement can be achieved by treating the conveying surface 40, such as a conveying wire or conveying mesh that conveys the laminated sheet formed by laminating the pulp fibers of the wet paper and the lyocell fiber web described above, as having irregularities and holes, and applying a water flow to the laminated sheet on this conveying surface to transfer the shape of the irregularities and holes to the sheet while entangling it.

[0036] In particular, when the convex portions are formed by hydroentanglement, it is preferable that the convex portions are formed on the lyocell surface side. As shown in Fig. 1, the preferred convex portions 60 can be formed by forming a conveying surface 40 for conveying a laminated sheet in which the pulp fibers of the wet paper 10 and the lyocell fiber web 20 are laminated, the conveying surface 40 having holes 50, and applying a water flow 30 from the wet paper surface side. The convex portions 60 are formed by the pulp fibers entangled with the lyocell fibers gathering in the holes 50, and fine pulp fibers can fall out of the holes 50, so that lint is particularly unlikely to occur.

[0037] The shape of the protrusions in the pulp-mixed nonwoven wipe of this embodiment is not necessarily limited because the edges of the shape are not clear, especially in the case of hydroentanglement, but is preferably circular, elliptical, nearly circular, or nearly elliptical. The size is also not limited, but in the case of a circular or elliptical shape, the radii L3 and L4, the minor axis L3, and the major axis L4 are preferably 2 to 5 mm.

[0038] On the other hand, the pulp-mixed nonwoven wipe of this embodiment has a (wet tensile strength) / (dry tensile strength) value of 0.8 or more in both the longitudinal and transverse directions, preferably 0.9 or more. A (wet tensile strength) / (dry tensile strength) value of 0.8 or more in both the longitudinal and transverse directions means that the difference between the strength when dry and the strength when wet is extremely small, and wiping properties are improved, especially in a wet state where water is absorbed. The pulp-mixed nonwoven wipe of this embodiment can achieve a difference between the strength when dry and the strength when wet of 0.8 or more by using 100% by mass of lyocell as the regenerated cellulose fiber to be entangled with the pulp fiber. In particular, it is easy to achieve a difference of 0.8 or more when the ratio of lyocell in the fiber is 20% by mass or more.

[0039] The specific dry tensile strength of the pulp-mixed nonwoven fabric wipe of this embodiment is not necessarily limited, but is preferably 30 to 80 N / 50 mm in the longitudinal direction and 10 to 50 N / 50 mm in the transverse direction. The wet tensile strength is also not necessarily limited, but is preferably 30 to 80 N / 50 mm in the longitudinal direction and 24 to 64 N / 50 mm in the transverse direction, and more preferably 27 to 72 N / 50 mm. This range is sufficient strength for wiping. The dry tensile strength and wet tensile strength are measured based on JIS L 1913 (2010) "6.3 Tensile strength and elongation (ISO method). Specific examples of the measuring device include the "Universal tension and compression tester TG-200N" manufactured by Minebea Co., Ltd. and its equivalents.

[0040] On the other hand, the pulp-mixed nonwoven wipe of this embodiment desirably has an MMD (variation of coefficient of friction) of 6.0 or less on both sides. MMD is one of the indicators of smoothness. If the MMD is within the above range, it can be said that the smoothness of the pulp-mixed nonwoven wipe is sufficient. The MMD is a value measured using a friction tester KES-SE, KES-SESRU, or an equivalent device manufactured by Kato Tech Co., Ltd. The MMD is the degree of variation from the MIU (mean coefficient of friction), and the smaller the value, the smoother it is. The measurement conditions are that the contact surface of the friction element is brought into contact with the surface of the measurement sample to which a tension of 20 g / cm is applied in a predetermined direction with a contact pressure of 25 g, and the friction element is moved 2 cm in approximately the same direction as the tension is applied at a speed of 0.1 cm / s. The measurement is performed five times, and the average value is taken as the MMD. The friction element is a piano wire sensor that is a standard accessory of the above tester. This piano wire sensor has a contact surface formed of 20 adjacent piano wires with a diameter of 0.5 mm, with a length and width of 10 mm. The contact surface has a unit bulge at the tip formed by 20 piano wires (with a curvature radius of 0.25 mm).

[0041] On the other hand, the pulp-mixed nonwoven wipe of this embodiment desirably has a softness value of 20cN / 100mm or less on both the front and back sides. If the softness value is 20cN / 100mm or less, it feels supple and soft for general use. The softness was measured according to the handle-o-meter method in accordance with JIS L 1096 E method. However, the test piece was 100mm x 100mm in size, and the clearance was 20mm. Measurements were performed five times in the vertical and horizontal directions on both the front and back sides, and the average value of the five measurements was expressed in units of cN / 100mm.

[0042] As described above, the pulp-mixed nonwoven wipe according to the present embodiment has excellent water absorption and strength even though it does not contain synthetic fibers derived from petroleum, and has excellent versatility suitable for cleaning, wiping, wiping off dirt and liquids from food, objects, and living organisms such as the human body. In addition, it produces little lint and has excellent heat resistance. Furthermore, it is sufficiently flexible and smooth. EXAMPLES

[0043] Next, tests were carried out on the pulp-mixed nonwoven wipe according to the present embodiment (Example) and other pulp-mixed nonwoven wipes (Comparative Example, Conventional Example, Commercial Product). All of the examples were pulp-mixed nonwoven wipes produced by hydroentanglement.

[0044] The comparative example contains rayon as the regenerated cellulose fiber. The conventional example and the commercially available product are pulp and synthetic fiber entangled. In the examples and the comparative example, the water pressure during hydroentanglement is 395 to 400 bar, and in the conventional example, it is 230 bar. In the examples, the lyocell fiber has a thickness of 1.67 dtex and a fiber length of 38 mm, and the rayon fiber has a thickness of 1.33 dtex and a fiber length of 38 mm. The pulp fiber used is softwood kraft pulp. In each example, no fiber type other than that shown in Table 1 is used.

[0045] The unevenness has the shape shown in Figure 1, and the shape of each concave (convex) is an ellipse (minor axis L3 = 2.8 mm x major axis L4 = 3.0 mm) that is slightly elongated in the direction perpendicular to the flow direction (CD direction), and the pitch is 4.2 mm in the flow direction (MD direction) L1 and 4.5 mm in the direction perpendicular to the flow direction L2.

[0046] The test results are shown in Tables 1 and 2. The physical properties of the examples and comparative examples are shown in Table 1. Since the fiber ratio in the commercially available product is unknown, only the constituent fibers are shown. The test methods were as follows.

[0047] (Tensile strength) Measurements were made based on JIS L 1913 (2010) "6.3 Tensile strength and elongation (ISO method). Dry and wet tensile strengths were measured. The test machine used was a load cell tensile tester TG-200N manufactured by Minebea Co., Ltd. Measurements were performed by clamping both ends of the test piece to the grips of the test machine, applying a tensile load to the sample in the vertical direction, and reading the indicated value (digital value) when the sample breaks. The tensile speed was 100 mm / min. Five sets of samples were prepared in both the vertical and horizontal directions and measurements were made five times each, and the average of the measured values ​​was taken as the tensile strength in each direction.

[0048] [Water absorption] The water absorption was measured according to the following (1) to (5). (1) Measure the mass of the test piece using an electronic balance (such as A&D HR300). (2) Pour 25°C water into a tray larger than the test specimen (e.g., inner dimensions: 215 mm x 160 mm) to a depth of approximately 20 mm. (3) The test piece is spread out on a rigid flat net (e.g., 120 mm x 120 mm, mesh size 15 mm) that is larger than or equal to the test piece, and then lowered into the tray containing the water so that the test piece is immersed in the water so that it comes into contact with the water surface. (4) When the water has sufficiently soaked into the surface of the test piece, raise the net directly above the water surface, pinch a corner of the test piece with tweezers, and leave it in that position for 30 seconds. (5) After 30 seconds, the mass of the test piece that has absorbed water is measured using an electronic balance and calculated using the following formula: 2 Calculate the amount of water absorbed per unit. Water absorption (g / m 2 ) = ((Mass of the water-absorbed test piece measured in (4) above) - (Mass of the test piece measured in (1) above)) x 100 (Note: m 2 (Multiply by 100 to convert to

[0049] [Oil absorption amount] The oil absorption was measured as follows (1) to (5). (1) Measure the mass of the test piece using an electronic balance (such as A&D HR300). (2) In a tray larger than the test specimen (for example, inner dimensions: 215 mm x 160 mm), pour salad oil (Nissin Salad Oil: manufactured by Nisshin Oillio Group, Ltd.) at 25°C to a depth of approximately 20 mm. (3) The test piece is spread out and placed on a rigid flat net (e.g., 120 mm x 120 mm, mesh size 30 mm) that is larger than or equal to the test piece, and then lowered into the tray containing the salad oil so that the test piece is immersed in the oil so that it comes into contact with the oil surface. (4) When the salad oil has soaked into the surface of the test piece, raise the flat net directly above the oil surface, leave it there for 30 seconds, then pick up a corner of the test piece with tweezers and transfer the test piece to a pre-weighed measurement container. At this time, do not allow more than 30 seconds from when the flat net is raised above the oil surface and left there until it is transferred to the measurement container. (5) The mass of the measuring vessel containing the test piece is measured using an electronic balance, and the mass of the test piece after oil absorption is calculated by subtracting the mass of the measuring vessel from the measured mass. Then, the mass of the test piece after oil absorption is calculated by the following formula: 2 The oil absorption per unit is calculated. Oil absorption (g / m 2 ) = ((Mass of the oil-absorbed test piece measured in (4) above) - (Mass of the test piece measured in (1) above)) x 100 (Note: m 2 (Multiply by 100 to convert to

[0050] [Water absorption speed] The water absorption rate was measured as follows (1) to (4). (1) Prepare a 100 mm x 100 mm test piece. (2) Place the test piece on a stand (such as a tripod for an alcohol lamp) that has a hole with a diameter of 40 mm or more in the center, so that the center of the test piece is positioned over the hole. (3) 300 μl of water at 25° C. is dropped with a micropipette at a height of 10 mm from the surface of the test piece to any point near the center of the test piece. This dropping can be done, for example, with an AS ONE Pipette Guy PG-1000, set to 300. (4) The time from the moment the water from the micropipette contacts the test piece to the moment the water completely penetrates the test piece is measured with a stopwatch, and this time is taken as the water absorption rate (sec). The completion of penetration is determined by visually confirming that the glossy reflection of water disappears from the surface of the test piece.

[0051] [Softness] Measurements were performed using the handle-o-meter method in accordance with JIS L 1096 E. However, the test pieces were 100 mm x 100 mm in size, and the clearance was 20 mm. Measurements were performed five times each in the vertical and horizontal directions on the front and back sides, and the average of the five measurements was expressed in units of cN / 100 mm.

[0052] [MMD] (Frictional resistance MIU) Measurements were performed using an automated surface tester KES-FB-4-AUTO manufactured by Kato Tech Co., Ltd. The contact surface of the frictional element was brought into contact with the surface of the measurement sample to which a tension of 20 g / cm was applied in a predetermined direction at a contact pressure of 25 g, and moved 2 cm at a speed of 0.1 cm / s in approximately the same direction as the tension was applied. The frictional element was a standard accessory 10 mm square piano wire sensor (20 pieces). MMD and MIU were measured five times for each surface, and the average values ​​were calculated.

[0053] [Lint removal performance (lint view tester)] The lint removal performance (lint view tester) was measured as follows (1) to (4). (1) Prepare a test piece measuring 240 mm x 200 mm. (2) Fold the test piece in half and soak it in pure water. Then, place two pieces of 300 mm x 300 mm filter paper (125 g / m 2 ) are placed between five pieces of the sample. (3) The sample is sandwiched between filter paper and a 2.86 kg iron roll (diameter 65 mm, face length 2500 mm) is moved back and forth five times over the filter paper to dehydrate it. (4) The sample is separated from the filter paper, and the wet two-fold test piece is unfolded into one sheet, which is then placed on a carrier sheet and the number of lint particles adhering to the sample is measured using an IGT Lint View Tester (manufactured by IGT Sisting Systems Co., Ltd.). The tape used for this measurement is number "D," which has the strongest adhesive strength, and the measurement is performed in the direction of a length of 240 mm by a width of 50 mm. The lint particles to be counted are visible and are 0.5 mm or larger. (5) The N number is the average of the numbers of visible defects measuring 0.5 mm or larger, 0.75 mm, 1.0 mm, 2.0 mm, and 3 mm or larger, measured three times in both directions in the flow direction (a total of six measurements). (6) As a reference value, the value of the pulp-mixed nonwoven wipe of Conventional Example 1, which contains pulp fiber and synthetic fiber (polypropylene fiber) in a ratio of 80:20 and is entangled by hydroentanglement, is set to "1", and a relative value is calculated. Note that the reason for using relative values ​​is that the adhesiveness of the adhesive tape used for the measurement changes depending on the measurement environment and over time, and the absolute numbers vary widely. For reference, absolute numbers are also shown.

[0054] [Lint removal performance (paper dust amount / mirror)] The lint removal performance (amount of paper powder / mirror) was measured as follows (1) to (3). (1) Prepare a test piece measuring 405 mm x 280 mm. (2) After immersing the test piece in tap water, squeeze it out between the palm of your hand and wipe the mirror while it is still wet. (3) The state of the paper powder adhering to the mirror is visually confirmed, and the condition is evaluated by giving a score of 1 to 9 points relative to Comparative Example 1, which is set as the standard of 10.

[0055] [Lint removal performance (paper dust amount / count number)] The lint removal performance (amount of paper powder / count number) was measured as follows (1) to (3). (1) Prepare a test piece measuring 405 mm x 280 mm. (2) After immersing the test piece in tap water, squeeze it out between the palm of your hand and, while still wet, wipe a 60 mm x 60 mm acrylic plate. (3) An arbitrary 24 mm x 18 mm area from the wiped area is magnified using a KEYENCE One-Shot 3D Measuring Macroscope VR-3200, and the number of paper particles within that area is visually counted. The relative values ​​of each test shown in Table 2 are values ​​where Conventional Example 1 is taken as 1.

[0056] [Table 1] [Table 2]

[0057] Looking at the test results in Table 1, the examples of the present invention had tensile strengths in both dry and wet conditions equal to or greater than those of the conventional examples in which the synthetic fiber was polypropylene. Furthermore, compared to the comparative examples in which the regenerated cellulose fiber was rayon, the difference in tensile strength between dry and wet conditions was small, and the strength did not decrease even when wet. In addition, the heat resistance temperature was excellent, with carbonization at 400 degrees without melting. Furthermore, the liquid absorbing properties, such as water absorbency, oil absorbency, and water absorption speed, were superior to those of conventional examples and commercially available products using synthetic fibers. These results demonstrate that the pulp-mixed nonwoven fabric sheet according to the present invention has excellent strength in both dry and wet states, and also has excellent liquid absorbency, even though it does not contain synthetic fibers derived from petroleum. Furthermore, looking at the results in Table 2, it can be seen that little lint was generated, and in particular, the material in which the unevenness was formed by hydroentanglement had excellent surface smoothness and softness, and also generated little lint. From the above results, it can be said that the pulp-mixed nonwoven fabric wipe of the present invention is a highly versatile pulp-mixed nonwoven fabric wipe suitable for cleaning, wiping, wiping off dirt and liquids from food, objects, and living organisms such as the human body. [Explanation of symbols]

[0058] 1... pulp-mixed nonwoven sheet, 10... pulp fiber layer (wet paper), 20... lyocell fiber web, 30... water flow, 40... conveying surface, 50... hole, 60... convex portion, L1... pitch of concave portion (convex portion), L2... minimum distance between concave portions (convex portions), L3... length of minor axis (diameter), L4... length of major axis (radius).

Claims

1. A pulp-mixed nonwoven wipe in which pulp fibers and regenerated cellulose fibers are entangled, Basis weight: 30 to 90 g / m ２ and The regenerated cellulose fiber is lyocell. A pulp-mixed nonwoven wipe.

2. The pulp-mixed nonwoven fabric wipe according to claim 1, wherein the blending ratio of pulp fiber to lyocell is 50:50 to 80:

20.

3. 3. The pulp-mixed nonwoven wipe according to claim 1 or 2, wherein the fiber length of the lyocell is 21 mm or more and 78 mm or less.

4. 3. The pulp-mixed nonwoven wipe according to claim 1 or 2, wherein the entanglement is achieved by hydroentanglement.

5. The pulp-mixed nonwoven fabric wipe according to claim 1 or 5, which has convex portions formed at a pitch of 2 to 6 mm on at least one surface.

6. 3. The pulp-mixed nonwoven fabric wipe according to claim 1, wherein the (wet tensile strength) / (dry tensile strength) ratio in both the machine direction and the cross direction is 0.8 or more.

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