Pulp-containing non-woven wipe

Abstract

To provide a pulp-containing non-woven wipe which has sufficient strength when dry, is excellent in liquid absorption, and produces a small amount of lint.SOLUTION: Provided is a pulp-containing non-woven wipe 1 obtained by entangling pulp fibers 10 and regenerated cellulose fibers 20 by water jets, having a basis weight of 30-90 g / m2, the regenerated cellulose fibers including rayon, and convex portions being formed on at least one surface by entanglement using water-jets 30.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, the 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 sufficient strength when dry, has excellent liquid absorbency, generates little lint, and is highly versatile and suitable for cleaning, wiping, and wiping off dirt and liquids from food, objects, and living organisms such as the human body. More preferably, the pulp-mixed nonwoven fabric wipe has excellent strength when wet and 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 measure is: A pulp-mixed nonwoven wipe in which pulp fibers and regenerated cellulose fibers are hydroentangled, Basis weight: 45~80g / m 2 and The regenerated cellulose fibers include rayon, A convex portion is formed by hydroentanglement on at least one surface. 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 fibers and regenerated cellulose fibers of 50:50 to 80:20.

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

[0012] The fourth measure is The regenerated cellulose fiber is a pulp-mixed nonwoven wipe according to the first or second aspect, which contains lyocell.

[0013] The fifth measure is: The pulp-mixed nonwoven fabric wipe according to the first or second aspect described above has a pitch of the protrusions of 2 to 6 mm. Effect of the Invention

[0014] According to the present invention, there is provided a pulp-mixed nonwoven fabric wipe that does not contain synthetic fibers derived from petroleum and yet has sufficient strength when dry, excellent liquid absorption, generates little lint, and is highly versatile and 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 has excellent strength when wet and excellent heat resistance. [Brief description of the drawings]

[0015] [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

[0016] 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.

[0017] 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 measured in accordance with JIS P 8124.

[0018] The thickness of the pulp-mixed nonwoven fabric wipe of this 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.

[0019] 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.

[0020] In addition, regenerated cellulose fibers derived from wood have 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 regenerated cellulose fibers, 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.

[0021] On the other hand, the regenerated cellulose fiber in the pulp-mixed nonwoven wipe of this embodiment contains rayon. The blending ratio of rayon in the regenerated cellulose fiber is not necessarily limited, but is preferably 50 to 100% by mass. Rayon is a regenerated cellulose fiber made from wood, not from petroleum like nylon or polyester. By making the regenerated cellulose fiber contain rayon, the strength when dry can be made sufficient for general use even if the blending ratio of synthetic fiber is 5% by mass or less, especially 0%. In addition, the regenerated cellulose fiber can be made excellent in water absorption, oil absorption, and water absorption speed, and can be easily used for general use. In particular, it can be easily used for wiping off liquids such as water and oil.

[0022] The fibers other than rayon in the regenerated cellulose fibers in the pulp-mixed nonwoven wipe of this embodiment are not necessarily limited, but are preferably lyocell. Lyocell is also a regenerated cellulose fiber produced by a solvent spinning method using wood as a raw material, not derived from petroleum materials like nylon and polyester. Lyocell is sometimes called Tencel. When lyocell is contained, the blending ratio of lyocell is preferably 20 to 50 mass%. When lyocell is contained, the strength when wet is increased. Therefore, by containing lyocell, the strength when dry and when wet is excellent, and further, the change in strength from dry to wet and from wet to dry is small. Therefore, it is easy to use in a use site where both wiping of dry objects and wiping of liquids are required, and in an application where wiping is performed by soaking in liquids such as water and liquid detergent.

[0023] The fiber length of the regenerated cellulose fiber in the pulp-mixed nonwoven wipe of this embodiment is preferably 21 mm to 78 mm, particularly preferably 28 mm to 65 mm. The regenerated cellulose fiber having a fiber length of 21 mm to 78 mm is preferably entangled with the pulp fiber, particularly the pulp fiber derived from coniferous trees, by hydroentanglement. Therefore, the pulp-mixed nonwoven wipe of this embodiment is less likely 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 (Metso Automation, Kayani / Fiber Lab) for the defibrated fiber after defibration in accordance with JIS P 8220. If it is not possible or difficult to measure using this fiber length measuring device, the fiber and the nonwoven fabric whose fiber length is known based on the information on "dtex" from the raw cotton production marker are observed under an electron microscope, and a comparison measurement is performed, and a judgment can be made from the comparison result.

[0024] The fiber thickness of the regenerated cellulose fiber 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 coniferous trees. 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.

[0025] 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 regenerated cellulose fibers, 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).

[0026] The blending ratio of pulp fibers and regenerated cellulose fibers in the pulp-mixed nonwoven wipe of this embodiment is not limited, and can be adjusted to pulp fibers:regenerated cellulose fibers = 10:90 to 90:10. Preferably, the ratio is pulp fibers:regenerated cellulose fibers = 50:50 to 80:20, and particularly preferably, the ratio is pulp fibers:regenerated cellulose fibers = 60:40 to 80:20. When the ratio is pulp fibers:regenerated cellulose fibers = 60:40 to 80:20, the liquid absorption property of the pulp fibers, the strength improvement of the regenerated cellulose fibers, and the suppression of lint generation are well balanced. The suppleness and softness are also good, resulting in a pulp-mixed nonwoven wipe with excellent versatility.

[0027] On the other hand, the pulp-mixed nonwoven wipe of this embodiment is a pulp-mixed nonwoven wipe by the spunlace method, which is obtained by entangling pulp fibers and regenerated cellulose fibers by hydroentanglement (spunlace method), and is also called a spunlace nonwoven fabric or a spunlace-type nonwoven fabric. When the pulp fibers and regenerated cellulose fibers are entangled by hydroentanglement, fine pulp fibers fall off during production due to the water flow, resulting in less generation of lint. In addition, the pulp-mixed nonwoven wipe of this embodiment may have fibers oriented 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.

[0028] 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 a regenerated cellulose fiber web 20 after carding to laminate the pulp fibers 10 in a wet paper state, and then, in accordance with spunlace technology also called water jet technology or water needle technology, a water stream 30 is sprayed and struck against the wet paper surface of a laminated sheet in which the wet paper 10 of pulp fibers and the regenerated cellulose fiber web 20 are laminated, so that the pulp fibers of the wet paper 10 penetrate into the regenerated cellulose fibers of the regenerated cellulose fiber web 20 to hydroentangle. In this hydroentanglement, the fiber length and fiber thickness of the pulp fibers and lyocell fibers derived from conifers are particularly preferable. The wet paper and the fiber web may be laminated in multiple layers, but it is preferable to laminate one layer each.

[0029] 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.

[0030] 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 sheet, the entanglement of the pulp fibers and the regenerated cellulose fiber nonwoven sheet is improved, and in particular, the penetration of the pulp fibers into the surface side of the regenerated cellulose fiber nonwoven sheet is improved, making it difficult for the pulp fibers to separate from the front and back, and making it difficult for lint to occur. In addition, pulp fibers derived from coniferous trees and a nonwoven fabric sheet of regenerated cellulose fibers having a fiber length of 21 mm or more and 78 mm or less are particularly suitably entangled in the spunlace method under these conditions.

[0031] The pulp-mixed nonwoven wipe of this embodiment is able to maintain the entanglement of the pulp fibers and the regenerated cellulose fiber nonwoven sheet and bond the fibers together by heat fusion using a binder (adhesive) and binder fibers such as heat-sealing fibers. However, the application of heat-sealing fibers or binders tends to reduce liquid absorbency and increases costs, and 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.

[0032] On the other hand, the pulp-mixed nonwoven wipe of this embodiment has protrusions 60 formed by hydroentanglement on at least one side as shown in Fig. 2. The protrusions 60 improve the wiping ability to scrape off dirt and increase the softness. The protrusions 60 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. Note that recesses corresponding to the protrusions may be formed on the opposite side of the protrusions.

[0033] The formation of the convex portions 60 by hydroentanglement can be achieved by treating the conveying surface 40, such as a conveying wire, conveying mesh, etc., that conveys the laminated sheet formed by stacking the pulp fibers of the wet paper and the regenerated cellulose 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.

[0034] Moreover, it is preferable that the convex portions 60 formed by this water flow entanglement are convex portions formed on the regenerated cellulose surface side. As shown in Fig. 1, this preferable convex portion 60 can be formed by having holes 50 on the conveying surface 40 conveying the laminated sheet in which the pulp fibers of the wet paper 10 and the regenerated cellulose fiber web 20 are laminated, 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 regenerated cellulose fibers gathering in the holes 50, and fine pulp fibers can fall out through the holes 50, so that lint is particularly unlikely to occur.

[0035] The pitch of the convex portions is not limited, but as shown in FIG. 2, the pitch L1 is preferably 2 to 6 mm. The pitch L1 refers to the distance between the convex portions 60 arranged regularly in the flow direction (MD direction) and the direction perpendicular to the flow direction (CD direction). 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. The shape of the convex portions 60 is not necessarily limited, particularly in the case of hydroentanglement, since the edges of the shape are not clear, but is preferably circular, elliptical, approximately circular, or approximately elliptical. The size is not limited, but in the case of a circle or an ellipse, the radii L3 and L4, the minor axis L3, and the major axis L4 are preferably 2 to 5 mm.

[0036] The specific dry tensile strength and wet tensile strength of the pulp-mixed nonwoven fabric wipe of this embodiment are not necessarily limited, but are preferably 30 to 80 N / 50 mm in the longitudinal direction and 10 to 25 N / 50 mm in the transverse direction both when dry and when wet. This range provides 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 measuring devices include the "Universal tension and compression tester TG-200N" manufactured by Minebea Co., Ltd. and equivalents.

[0037] 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).

[0038] 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.

[0039] As described above, the pulp-mixed nonwoven wipe according to the present embodiment has excellent liquid 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

[0040] 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.

[0041] The comparative example contains only lyocell as the regenerated cellulose fiber. The conventional example and the commercially available product are pulp and synthetic fiber entangled. In the examples and comparative examples, the water pressure during hydroentanglement is 395 to 400 bar, and in the conventional example, it is 230 bar. The rayon fiber in the examples has a thickness of 1.33 dtex and a fiber length of 38 mm. The lyocell fiber in the comparative examples and examples has a thickness of 1.67 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.

[0042] (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.

[0043] [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 and placed 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

[0044] [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

[0045] [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.

[0046] [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.

[0047] [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.

[0048] [Lint removal performance (lint view tester)] The lint removal performance was measured according to the following (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 standard value, the value of a commercially available pulp-mixed nonwoven wipe, which contains pulp fiber and synthetic fiber (polypropylene fiber) in a ratio of 80:20 and is entangled by hydroentanglement, is set as "1," and a relative value is calculated. Note that the reason for using a relative value is that the adhesiveness of the adhesive tape used for the measurement changes depending on the measurement environment and over time, resulting in large variations in the absolute numbers.

[0049] [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.

[0050] [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.

[0051] [Table 1] [Table 2]

[0052] Looking at the test results in Table 1, the tensile strength in the longitudinal direction when dry for Example 2 was comparable to that of Conventional Example 3, which uses pulp fiber and synthetic polypropylene fiber, and Commercial Product 2, which contains synthetic PET fiber. The tensile strength in the transverse direction when dry for Example 2 was comparable to that of Commercial Products 1 and 2. Furthermore, for Example 2, which contains rayon and lyocell, the difference between the tensile strength when dry and when wet was small, and the strength when wet was also sufficient. Furthermore, the liquid absorption properties, such as water absorption, oil absorption, and water absorption speed, were significantly superior to those of conventional examples and commercially available products. These results show that the pulp-mixed nonwoven fabric sheet of the present invention has excellent liquid absorption properties and sufficient strength when dry, even though it does not contain synthetic fibers derived from petroleum. In addition, the incorporation of lyocell increases the strength when wet. Furthermore, looking at the results in Table 2, the examples having unevenness on the front and back surfaces showed excellent surface smoothness and softness, and in particular produced less 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]

[0053] 1... pulp-mixed nonwoven sheet, 10... pulp fiber layer (wet paper), 20... regenerated cellulose 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... minor axis length (diameter), L4... major axis length (radius).

Claims

1. A pulp-mixed nonwoven wipe in which pulp fibers and regenerated cellulose fibers are hydroentangled, Basis weight: 30 to 90 g / m ２ and The regenerated cellulose fibers include rayon, A convex portion is formed by hydroentanglement on at least one surface. A pulp-mixed nonwoven wipe.

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

20.

3. 3. The pulp-mixed nonwoven fabric wipe according to claim 1 or 2, wherein the regenerated cellulose fibers have a fiber length of 21 mm or more and 78 mm or less.

4. 3. The pulp-mixed nonwoven wipe of claim 1 or 2, wherein the regenerated cellulose fibers comprise lyocell.

5. The pulp-mixed nonwoven fabric wipe according to claim 1 or 2, wherein the pitch of the protrusions is 2 to 6 mm.

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