Paper Industrial Wipers

Abstract

To provide an industrial paper wiper having excellent water absorption, usability (a feeling of volume held in hand) and robustness, having favorable wiping-off properties in both sides of the wiper and being comfortable in wiping.SOLUTION: An industrial paper wiper is formed by plying up 1-ply base paper into 3-ply or more and 4-ply or less, embossing and integrating them, where a basis weight of the wiper is 55.0 g / m2 or more and 101.0 g / m2 or less, an area rate of an embossed part formed by embossing to the wiper is 25% or more and 50% or less, and the height of the embossment is 250 μm or more and 650 μm or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The present invention relates to embossed paper industrial wipers. [Background technology]

[0002] Industrial wipers (hereinafter also referred to as paper industrial wipers) made from pulp or recycled paper (cellulose only, excluding nonwoven fabric) are known.

[0003] Most products on the market are 2 to 6 ply, and come in a variety of embossing shapes (matched embossing, pin embossing, etc.) and product forms (pop-up type, quarter-fold type, handy type, etc.).

[0004] The qualities required for paper industrial wipers include absorbency, usability (ease of wiping, volume in the hand), and durability.

[0005] For example, Patent Document 1 discloses prior art documents for such paper industrial wipers. The fibers are 100% pulp, which contains 70 to 100 parts by weight of NBKP (softwood kraft pulp), and the pulp is made by adding 0.125 to 1.25 parts by weight of a wet strength agent and 0.01 to 0.5 parts by weight of a softener per 100 parts by weight of the fibers. The wipes are calendered, have a softness (handle-ometer method: in accordance with JIS L 1096E) of 3.0 to 12.0 g, and have an MMD of 7.0 to 20.0 on each side. The wipes are stored in a cut-off state for each use, and each cut-off and stored paper wipe is folded in half with the side with the larger mean deviation of the coefficient of friction (MMD) of the wipe surface inside, and the folded sides are stacked so that they are in contact with each other and interlock with each other, and are removed by popping up when used. Patent Document 2 also describes a laminate in which the number of stacked paper sheets is 4 or more and 8 or less, and at least one of the paper sheets in the surface layer of the laminate has a basis weight of 14.0 gsm to 19.0 gsm, an opening rate of the paper sheet is 2.1% to 7.5%, and the water absorption of the laminate is 300 g / m 2 ~760g / m 2 An industrial wiping sheet characterized by: [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 5366596 [Patent Document 2] Patent No. 5978100 Summary of the Invention [Problem to be solved by the invention]

[0007] Paper industrial wipers are embossed to improve absorbency, ease of wiping, and volume in the hand, but generally, the lower the embossed area ratio (the ratio of embossed areas to the entire wiper), the higher the embossed height remaining on the product, which is advantageous for absorbency, ease of wiping, and volume in the hand. Also, many wiper products on the market have an embossed area ratio of less than 10%.

[0008] On the other hand, paper industrial wipers with a low embossed area ratio have the problem that the wiping feel (ease of wiping off dirt) varies depending on the front and back of the wiper (embossed concave and convex sides), making them difficult to use. On the other hand, if the area ratio is increased (towards 50%), the difference in wiping feel between the front and back of the wiper becomes smaller, but the embossing on the product is less likely to remain (the embossing is easily crushed during the processing process), resulting in poor absorbency and usability (volume in the hand), and the wiping feel also worsens on both the front and back of the wiper. In addition to the embossing, the number of plies (number of plies) of the wiper base paper also has problems. If it is too few, it will be less durable and less absorbent, and if it is too many, it will be stiff and not comfortable to wipe with.

[0009] Therefore, it was difficult with conventional technology to achieve a good balance between the following: good water absorption, feel in use (volume when held in the hand), and durability; small difference in wiping feel between the front and back of the wiper (good wiping feel on both the front and back); and good wiping comfort of the wiper.

[0010] The present invention has been made in view of the above circumstances, and aims to provide a paper industrial wiper that is excellent in water absorbency, usability (volume when held in the hand), durability, ease of wiping off dirt from both the front and back of the wiper, and excellent wiping comfort. [Means for solving the problem]

[0011] The inventors have conducted extensive research and have found that by plying up a predetermined number of base papers, embossing them to a predetermined area ratio and height to combine them, and setting the basis weight within a predetermined range, it is possible to produce a paper industrial wiper that is excellent in water absorbency, usability (volume when held in the hand), and durability, and that is easy to wipe away dirt from both the front and back of the wiper and also has an excellent wiping feel, thereby completing the present invention.

[0012] (1) The first aspect of the present invention is a paper industrial wiper in which one ply of base paper is plyed up to three or more plies or less and four or less plies, and the ply is embossed and integrated, and the basis weight of the wiper is 55.0 g / m 2 More than 101.0g / m 2 Hereinafter, the term "paper industrial wiper" refers to a wiper characterized in that the area ratio of the embossing on the wiper created by the embossing process is 25% or more and 50% or less, and the height of the embossing is 250 μm or more and 650 μm or less.

[0013] (2) A second aspect of the present invention is the paper industrial wiper according to (1), characterized in that the number of plies is three.

[0014] (3) A third aspect of the present invention is a paper industrial wiper according to (1) or (2), characterized in that the paper thickness of the wiper is 400 μm or more per product ply and 800 μm or less per product ply.

[0015] (4) A fourth aspect of the present invention is a paper industrial wiper according to any one of (1) to (3), characterized in that the square root GMT of the product of the dry longitudinal tensile strength DMDT and the dry transverse tensile strength DCDT of the wiper according to JIS P 8113 is 10.4 N / 25 mm or more and 25.0 N / 25 mm or less.

[0016] (5) The fifth aspect of the present invention is a paper industrial wiper according to any one of (1) to (4), wherein the area of ​​one embossment of the embossment is 1.0 mm 2 Over 7.0mm 2 It is characterized by the following:

[0017] (6) A sixth aspect of the present invention is a paper industrial wiper according to any one of (1) to (5), wherein the wiper after plying has a basis weight of 18.7 g / m when measured in a single ply state. 2 More than 26.7g / m 2 It is characterized by the following:

[0018] (7) A seventh aspect of the present invention is a paper industrial wiper according to any one of (1) to (6), characterized in that the paper thickness of the non-embossed portion of the wiper after plying is measured in a state where the wiper is made up of 10 plies and has a thickness of 0.78 mm / 10 plies or more and 1.25 mm / 10 plies or less.

[0019] (8) An eighth aspect of the present invention is a paper industrial wiper according to any one of (1) to (7), characterized in that the square root (GMT) of the product of the dry longitudinal tensile strength (DMDT) and the dry transverse tensile strength (DCDT) according to JIS P 8113, measured in a single ply state after plying, is 5.0 N / 25 mm or more and 11.9 N / 25 mm or less.

[0020] (9) A ninth aspect of the present invention is a paper industrial wiper according to any one of (1) to (8), characterized in that the wiper is folded into four. [Effects of the Invention]

[0021] According to the present invention, it is possible to provide a paper industrial wiper that is excellent in water absorbency, usability (volume when held in the hand), durability, ease of wiping off dirt from both the front and back of the wiper, and excellent wiping comfort. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 2 is a cross-sectional view of an embossed portion of the paper industrial wiper according to the present embodiment. [Figure 2] FIG. 2 is a plan view of the embossed portion of the paper industrial wiper according to the present embodiment, viewed from the convex side. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. The following present embodiment is an example for explaining the present invention, and is not intended to limit the present invention to the following content. The present invention can be carried out by appropriately modifying it within the scope of its gist.

[0024] In the drawings, the same elements are denoted by the same reference numerals, and redundant explanations will be omitted. Furthermore, unless otherwise specified, the positional relationships, such as up, down, left, and right, are based on the positional relationships shown in the drawings. Furthermore, the dimensional ratios of the drawings are not limited to those shown in the drawings.

[0025] <Paper industrial wipers> As shown in the cross-sectional view of Figure 1, the industrial paper wiper 1 according to this embodiment is made by plying (laminating) three to four plies of base paper 10 and embossing (applying embossments 20) to integrate them. In this case, the number of plies is three or four, and three is more preferable. By using three or four plies, the industrial paper wiper 1 is strong and has adequate water absorbency, and also has an adequate elastic feel when wiping, resulting in a good wiping comfort. The longitudinal dimension of the industrial paper wiper 1 is preferably 330 mm or more and 360 mm or less, and the width dimension is preferably 320 mm or more and 350 mm or less. The industrial paper wiper 1 may also be a so-called square shape, in which the longitudinal dimension and the width dimension are equal. The product form of the industrial paper wiper 1 is not particularly limited as long as it is a form used in ordinary industrial wiper products, such as a pop-up type, a four-fold type, or a handy type, but a four-fold type is particularly preferred. When folded in four, it has good water absorbency when used to wipe moisture off an object, and also has an excellent feel in use (volume when held in the hand).

[0026] The basis weight of paper industrial wiper 1 is 55.0 g / m 2 More than 101.0g / m 2 or less, 61.2 g / m 2 More than 86.7g / m 2 By setting the basis weight within the above range, the paper industrial wiper 1 can be made to have good absorbency, durability, and a good wiping feel. In addition, the basis weight of the paper industrial wiper 1 after plying was measured in the state of one ply, and was 18.7 g / m 2 More than 26.7g / m2 Preferably, it is 20.0 g / m or less. 2 More than 25.3g / m 2 It is more preferable that the basis weight is less than or equal to 1000 gram. By setting the basis weight in the single-ply state within the above range, an industrial paper wiper 1 can be obtained that combines water absorbency, durability, and a good wiping feel. In this case, "after plying up" refers to the state after one ply of base paper has been plyed up and embossed to form an integrated body. The basis weight is measured in accordance with JIS P 8124.

[0027] The paper thickness T of the industrial paper wiper 1 is preferably 400 μm / product ply number or more and 800 μm / product ply number or less, and more preferably 500 μm / product ply number or more and 700 μm / product ply number or less. By setting the paper thickness T within the above numerical range, the industrial paper wiper 1 can be made to have an excellent feel in use (volume in the hand) and a good wiping sensation. The "product ply number" in the unit of paper thickness T refers to measuring paper thickness T without increasing or decreasing the plies of the paper industrial wiper 1 product (processed paper industrial wiper 1, not base paper 10). Paper thickness T can be measured using a thickness gauge (for example, Ozaki Seisakusho's dial thickness gauge "PEACOCK") under the conditions of JIS P 8111 (23±1°C, 50±2% relative humidity), with a measurement load of 3.7 kPa and a probe diameter of 3 mm, by placing a sample (paper industrial wiper 1) between the probe and the measuring table, and reading the gauge when the probe is lowered at a speed of 1 mm per second or less.

[0028] Furthermore, when the ply-up industrial paper wiper 1 is made into 10 plies, the paper thickness of the non-embossed portion is measured, preferably from 0.78 mm / 10 plies to 1.25 mm / 10 plies, and more preferably from 0.89 mm / 10 plies to 1.13 mm / 10 plies. By setting the paper thickness of the non-embossed portion of the 10 plies in the ply-up industrial paper wiper 1 within the above numerical range, the industrial paper wiper 1 can be made to have an excellent feel in use (volume when held in the hand) and a good wiping sensation. In this case, 10 plies refers to the state in which the ply-up industrial paper wiper 1 is peeled off and returned to a 1-ply state, and then the returned 1-ply state is stacked on top of each other to form 10 plies.

[0029] The square root GMT of the product of the dry longitudinal tensile strength DMDT and the dry transverse tensile strength DCDT of the industrial paper wiper 1 according to JIS P 8113 is preferably 10.4 N / 25 mm or more and 25.0 N / 25 mm or less, and more preferably 12.8 N / 25 mm or more and 20.6 N / 25 mm or less. If the GMT is within the above numerical range, the industrial paper wiper 1 can be made to be strong (durable). Furthermore, when the ply-up industrial paper wiper 1 is measured in a single-ply state, the square root GMT of the product of the dry longitudinal tensile strength DMDT and the dry transverse tensile strength DCDT according to JIS P 8113 is preferably 5.0 N / 25 mm or more and 11.9 N / 25 mm or less, and more preferably 6.1 N / 25 mm or more and 9.8 N / 25 mm or less. Having a GMT in a single-ply state within the above numerical range ensures that the industrial paper wiper 1 is strong (durable). The tensile strengths in each direction in a dry state are all measured in accordance with JIS P 8113, and the GMT is calculated as the square root of the product of these tensile strengths.

[0030] When adjusting the strength after ply-up, methods such as beating the base paper 10 with a double disc refiner (DDR) or adding a wet strength agent or a dry strength agent can be appropriately selected, as described below. The wet strength agent is not particularly limited, but a polyamide polyamine epichlorohydrin-based agent is preferred. A dry strength agent may also be used, with a PAM-based dry strength agent being preferred. The wet strength agent may also contain an auxiliary agent, with an anionic polyacrylamide resin being preferred as the auxiliary agent for the wet strength agent. From the viewpoint of water absorption rate, the addition rate of the strength agent and auxiliary agent is preferably 1.0% or less based on the bone dry pulp weight. Adding a large amount of agent may result in poor water absorption rate.

[0031] (Embossed) The embossing applied to the industrial paper wiper 1 according to this embodiment involves applying embossments 20 in a generally regular, repeated pattern to integrate multiple sheets of base paper 10. By applying the embossments 20, the concave side of the embossments 20 becomes a concave surface S, and the convex side becomes a convex surface B. Note that the processing form of the embossments 20 is not important, but a matched embossing method is preferred because the embossments 20 tend to remain on the industrial paper wiper 1. The height of the portion of the industrial paper wiper 1 where the embossment 20 is formed, i.e., the height of the embossment 20 shown in FIG. 1 (embossment height H), is 250 μm or more and 650 μm or less, and preferably 350 μm or more and 550 μm or less. When the embossment height H is within the above numerical range, the industrial paper wiper 1 can be made to have an excellent feel in use (volume when held in the hand) and a good wiping sensation. The embossment height H is calculated by measuring the height of the embossment 20 of the industrial paper wiper 1 with a 3D microscope VR-3000 (manufactured by Keyence Corporation) and averaging the measured values ​​at 30 points.

[0032] 2, which shows the embossed portion of the industrial paper wiper 1 shown in FIG. 1 viewed from the convex surface B side, the area ratio of the embossments 20 on the industrial paper wiper 1 is 25% to 50%, and preferably 30% to 45%. When the area ratio is within the above numerical range, the industrial paper wiper 1 can be made to have an excellent feel in use (volume when held in the hand) and good ease of wiping off dirt from both the front and back of the wiper. The area ratio refers to the area ratio of the embossments 20 per unit area on the industrial paper wiper 1. In addition, the area of ​​one embossment of Emboss 20 is 1.0 mm 2 Over 7.0mm 2 Preferably, it is 1.8 mm or less. 2 Over 5.0mm 2 If the area of ​​one embossment is within the above range, the industrial paper wiper 1 can have a better feel in use (volume when held in the hand) and be easier to wipe off dirt from both the front and back of the wiper.

[0033] The area of ​​each embossment 20 is measured from the convex surface B of the industrial paper wiper 1 using a microscope VHX-6000 (manufactured by Keyence Corporation), and the average value of 30 points is defined as the area of ​​one embossment. The area ratio is calculated as (total area of ​​embossments 20 / area calculated by length x width of embossed area A) x 100 (%) in embossed area A shown in Figure 2. In this case, the embossments 20 on the boundary of embossed area A are counted as 1 / 2, and the embossments 20 at the four corners are counted as 1 / 4. Note that the embossing pattern shown in Figure 2 is merely an example. Even if the embossing pattern is different, a repeating area (an area where the same pattern is repeated) like that shown in Figure 2 is selected and the area ratio is measured (i.e., the area ratio will be the same regardless of how the repeating area is surrounded). Although the embossment 20 is substantially circular in FIG. 2, the shape of the embossment 20 is not particularly limited, and one or more shapes can be freely selected from a circle, an ellipse, a polygon, a star, etc.

[0034] (base paper) The base paper 10 (before plying) used to manufacture the paper industrial wiper 1 is not particularly limited in terms of the type of raw material, and can be a mixture of one or more types of bleached pulp, unbleached pulp, recycled raw materials derived from paper cartons, etc. The raw material composition can be softwood kraft pulp, hardwood kraft pulp, or pulp recycled from milk cartons (MSF), but from the viewpoint of water absorbency, it is preferable to use 100% virgin pulp. From the viewpoint of the strength of the final paper industrial wiper 1, it is preferable to use 80% or more softwood kraft pulp, more preferably 90% or more, and even more preferably 100%.

[0035] As described above, according to this embodiment, it is possible to provide a paper industrial wiper 1 that is excellent in water absorbency, usability (volume when held in the hand), and durability, and that is easy to wipe off dirt from both the front and back of the wiper, and also has an excellent wiping feel. [Example]

[0036] The present invention will be explained in more detail with reference to the following examples and comparative examples, but the present invention is not limited to these examples in any way.

[0037] Under the conditions shown in Tables 1 and 2, paper industrial wipers (products) were produced for each of Examples 1 to 13 and Comparative Examples 1 to 8, and the following evaluations were carried out. Note that each parameter other than the evaluations below was measured according to the standards or measurement methods described above.

[0038] (TWA) The water absorption was evaluated by the amount of water absorbed per unit area (TWA). The TWA values ​​measured by the following measurement method were evaluated according to the following criteria. 240g / m 2 Above: Excellent (especially able to absorb a lot of water) 220g / m 2 More than 240g / m 2 Less than: Good (can absorb a lot of water) 200g / m 2 More than 220g / m 2 Less than: Acceptable (no problem with water absorption) 200g / m 2 Less than: Not acceptable (low water absorption)

[0039] The total water absorbency (TWA) was measured by first cutting the obtained paper industrial wiper into a 76 x 76 mm square test piece and measuring the dry mass (W1). After immersing the test piece in distilled water for 2 minutes, the test piece was hung in a stretched state (RH 100%) with one corner of the test piece positioned at the top, supported by this top and the two adjacent corners, and then left for 30 minutes. The mass (W2) was then measured. The value of (W2 - W1) was then calculated, and this value was applied to the sample per 1 m. 2 Water retention capacity per unit (g / m 2 The amount of water absorbed per unit area (TWA) was calculated by converting the amount of water absorbed per unit area (TWA).

[0040] (Easy to wipe off dirt from each surface) The concave and convex surfaces of paper industrial wipers were evaluated for ease of wiping off dirt and other materials. Sensory evaluation was conducted by 60 people, who each rated the wipes on a scale of 1 to 5. The overall evaluation was based on the following criteria: "Excellent ◎": Particularly easy to wipe off, and dirt comes off very easily. Average score of 60 people is 4.0 points or more. "Good": Easy to wipe off and removes dirt. Average score is between 3.0 and 4.0 points. "Fair △": No problem in wiping off dirt, etc. Average score is 2.0 points or more but less than 3.0 points "Not Good": Difficult to wipe off and dirt is difficult to remove. Average score is less than 2.0 points.

[0041] (Wiper blade handling) A sensory evaluation of the feel of the paper industrial wipers in the hand was conducted by 60 people, who each rated them on a scale of 1 to 5. The overall evaluation was based on the following criteria: "Excellent ◎": When you pick up the wiper, you can feel the volume, and it gives you a sense of security when using it. Average score of 60 people was 4.0 points or more. "Good": When you pick up the wiper, it feels voluminous and gives you a sense of security when using it. The average score of 60 people was between 3.0 and 4.0 points. "Fair △": When picking up the wiper, it feels a little bulky. There are no particular problems when using it. The average score of 60 people was between 2.0 and 3.0 points. "Failed x": The wiper has no volume and feels flimsy, making it unsafe to use. Average score is less than 2.0 points.

[0042] (Wiper durability) A sensory evaluation of the durability of the wiper when wiping an object was conducted by 60 people, who each rated it on a scale of 1 to 5. The overall evaluation was based on the following criteria: "Excellent ◎": When wiping an object with the wiper, it feels particularly resistant to tearing. Average score of 60 people was 4.0 points or more. "Good": When wiping an object with the wiper, it feels less likely to tear. Average score is between 3.0 and 4.0 points. "Fair △": When wiping an object with the wiper, there is some tearing, but there is no problem in use. Average score is between 2.0 and 3.0 points. "Poor ×": The wiper is easily torn when wiping the target object, making it difficult to use. Average score is less than 2.0 points.

[0043] (Wiper wiping comfort) A sensory evaluation of the wiping feel of paper industrial wipers was conducted by 60 people, who each rated the wipes on a scale of 1 to 5. The overall evaluation was based on the following criteria: "Excellent ◎": The wiper is elastic, has a particularly good wiping feel, and can wipe objects particularly smoothly. Average score of 60 people was 4.0 points or more. "Good": The wiper has a moderate elasticity, is comfortable to wipe, and can wipe objects smoothly. The average score of 60 people was between 3.0 and 4.0 points. "Fair △": The wiper feels a little elastic, and the wiping comfort is at a level where there are no problems. The average score of the 60 people's evaluations was between 2.0 and 3.0 points. "Poor x": The wiper has no elasticity and is not comfortable to wipe objects. Average score is less than 2.0 points.

[0044] The conditions and evaluation results of each example are shown in Table 1, and the conditions and evaluation results of each comparative example are shown in Table 2. Each evaluation of △ (fair) or higher was considered to be pass.

[0045] [Table 1]

[0046] [Table 2]

[0047] From the above, it was at least confirmed that this example can provide a paper industrial wiper that is excellent in water absorbency, usability (volume when held in the hand), and durability, and that is easy to wipe off dirt from both the front and back of the wiper, and that also has an excellent wiping feel. [Explanation of symbols]

[0048] 1. Paper industrial wipes 10 Base paper 20 Embossing H Embossing height T paper thickness S concave B Convex A Embossed Area

Claims

1. A paper industrial wiper in which one ply of base paper is plied up to three to four plies, and then embossed to form an integrated structure, The basis weight of the wiper is 55.0 g / m ２ 101.0g / m or more ２ The area ratio of the embossed portion on the wiper surface is 25% or more and 50% or less, and the height of the embossed portion is 250 μm or more and 650 μm or less. The paper thickness when measuring the non-embossed portion with the wiper after ply-up set to 10 plies is 0.78 mm / 10 plies or more and 1.25 mm / 10 plies or less, A paper industrial wiper characterized in that, when the wiper after plying is measured in a single-ply state, the square root GMT of the product of the dry longitudinal tensile strength DMDT and the dry transverse tensile strength DCDT according to JIS P 8113 is 5.0 N / 25 mm or more and 11.9 N / 25 mm or less.

2. 2. The paper industry wiper according to claim 1, characterized in that the number of plies is three.

3. 3. The paper industrial wiper according to claim 1 or 2, wherein the paper thickness of the wiper is 400 μm or more per number of plies of the product and 800 μm or less per number of plies of the product.

4. 4. The paper industrial wiper according to claim 1, wherein the square root (GMT) of the product of the dry tensile strength (DMDT) in the machine direction and the dry tensile strength (DCDT) in the cross direction according to JIS P 8113 of the wiper is 10.4 N / 25 mm or more and 25.0 N / 25 mm or less.

5. The area of ​​each embossment is 1.0 mm ２ Over 7.0 mm ２ 5. The paper industrial wiper according to any one of claims 1 to 4, characterized in that:

6. The basis weight of the wiper after plying was measured in one ply state was 18.7 g / m ２ 26.7g / m or more ２ 6. The paper industrial wiper according to any one of claims 1 to 5, characterized in that:

7. 7. The paper industrial wiper according to claim 1, wherein the wiper is folded in four.

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