JP4842636B2 - Non-woven wiper - Google Patents

Description

  The present invention relates to a non-woven wiper for efficiently wiping and capturing particles having a relatively small diameter such as dust.

  Conventionally, various techniques have been proposed as wipers for wiping tables and floors and capturing earth and sand and dust. As an example, Japanese Patent Application Laid-Open No. 11-56727 (Patent Document 1) is formed by laminating and integrating two or more kinds of nonwoven fabric layers, and at least one surface is mainly composed of highly crimped fibers. A non-woven wiper is disclosed which comprises a non-woven fabric layer having a surface and a strength-imparting non-woven layer composed mainly of heat-sealing fibers. According to this technology, the highly crimped fiber mainly constituting the surface nonwoven fabric layer ensures the wiper wiping efficiency with respect to relatively large particles, and the strength imparted nonwoven fabric layer laminated and integrated with the layer is a heat-bonded fiber. Therefore, it is possible to impart dimensional stability to the entire wiper.

  JP 2003-230519 A (Patent Document 2) discloses a bulky sheet in which a fiber web mainly composed of heat-fusible fibers is laminated on one side or both sides of a net-like sheet and melted and integrated by a hot air penetration method. Floor cleaning sheets have been proposed. Further, in this publication technique, irregularities with the mesh sheet as a support are formed by the hot air penetration described above, and furthermore, individual fibers are joined by point bonding by melting, and a bulky state with many voids in the sheet is obtained. The form formed is disclosed. Further, such a fiber web has PP / PE, PP / PP, PP / EVA, PET / PE, PET / PP, PET / EVA, PET / PET and other heat-fusible conjugate fibers as essential components. There is a disclosure. By adopting such a configuration, the manufacturing cost is relatively low due to the hot air penetration method, and since individual fibers are joined by point bonding by melting, there are advantages such as excellent capture performance of hair and the like. It is said.

JP-A-11-56727 ([Claims], [Embodiments of the Invention], [Effects of the Invention]) JP 2003-230519 A ([Claims], [Effects of the Invention])

  As described above, the conventionally known techniques include an improvement in capture performance using high crimped fibers as disclosed in Patent Document 1, and a series of heats as disclosed in Patent Document 1 and Patent Document 2. It is expected that the wiping object having a particle size equal to or larger than the fiber diameter, such as the shape stability or seized sand and dust, by using the fusible fiber is physically held in the fiber gap of the wiping material. Is. However, in any conventional technique, only the capture performance is expected due to the physical size relationship between the thickness and fiber gap of the fibers constituting the wiping material and the object to be wiped, which is smaller than the fiber diameter. There was a problem that it was difficult to substantially wipe off and capture dust.

  Inventor according to the present application, in view of such problems of the prior art, as a result of repeated intensive studies to capture a wide range of wiping objects by utilizing the tackiness of the surface of the heat-sealing fiber, The present invention has been completed. Accordingly, an object of the present invention is to provide a nonwoven fabric wiper capable of efficiently collecting dust.

Order to achieve these objects, according to the configuration of the present invention, the nonwoven fabric wiper and constituting fibers and thermal bonding fibers is formed by bonding between the fibers, the thermoplastic resin constituting the thermally fused fibers described above, the It is characterized by having a durometer hardness (HDD) of 55 or less while being exposed on the surface of the heat-sealing fiber . Here, “HDD” means the hardness measured by the durometer D type in “Plastic Durometer Hardness Test Method”, which is JIS K7215 (1986). ".

  Moreover, it is suitable to make the thermoplastic resin which comprises the heat-fusion fiber mentioned above into a polyethylene polymer. Further, as the polyethylene polymer, one or a mixture of two or more selected from ethylene-vinyl acetate copolymer (EVA), ethylene-methyl acrylate copolymer (EMA) and low density polyethylene (LDPE) is used. Is preferred.

  Moreover, in the structure of the nonwoven fabric wiper of this invention, it is preferable to make the weight ratio of the constituent fiber mentioned above and the heat-fusion fiber mentioned above into the range of 80 / 20-35 / 65. Further, as the constituent fiber, it is preferable to use a latent crimpable fiber having a general number of crimps to be described later in the web preparation and expressing a large number of crimps by subsequent heat treatment.

  The nonwoven fabric wiper according to the present invention can capture relatively fine dust mainly on the surface of the heat-sealing fiber having the above-described characteristics by adopting the above-described configuration. Therefore, by applying the present invention, it can be expected to efficiently capture an object to be wiped that is difficult to capture only with a physical gap in the fiber web, such as dust.

  Hereinafter, preferred embodiments of the present invention will be described in detail. First, the heat sealing | fusion fiber which comprises the nonwoven fabric wiper of this invention is demonstrated. The heat-sealable fiber used in the present invention is bonded to the above-described constituent fibers or the heat-sealable fiber itself, and at least exposed on the surface of the heat-sealable fiber (contact with the object to be wiped is possible) The above-mentioned HDD 55 or lower is used as the thermoplastic resin. The durometer hardness is determined according to JIS K7100 “Standard Conditioning of Plastics and Standard Conditions of Test Place”, that is, standard temperature condition class 2 (temperature 23 ± 2 ° C.) and standard humidity condition class 2 (relative humidity 50 ±). 5%) is an index that defines the hardness of a plastic conditioned for 88 hours or more. By adopting an exposed thermoplastic resin having a hardness equal to or less than the numerical conditions described above, it has a kind of tackiness depending on the surface state that is relatively plastic, so that dust having a relatively small particle size, etc. It is considered that the capture performance is exhibited (detailed later). Therefore, as a cross-sectional configuration of the heat-sealing fiber that can be applied to the present invention, it is preferable to take the form of a side-by-side type or a core-sheath type composite fiber, and in particular, the exposed ratio of a predetermined thermoplastic resin is a side-by-side type. A core-sheath type heat-sealing fiber that can be taken larger than that is preferable.

  As a suitable thermoplastic resin that satisfies the HDD 55 or lower, it is preferable that the thermoplastic resin that constitutes the above-described heat-bonding fiber employs a polyethylene copolymer. By using such a heat-bonding fiber having a thermoplastic resin that satisfies the HDD, a kind of tackiness is imparted to the wiping surface of the wiper, so that it can capture dust and the like having a relatively small particle size. Can be demonstrated. In particular, as a thermoplastic resin constituting such a heat-fusible fiber, an ethylene-vinyl acetate copolymer (EVA: HDD43 when the composition ratio of vinyl acetate in the copolymer is 6% by weight), ethylene-methyl acrylate It is most preferable to employ a polyethylene copolymer alone such as a copolymer (EMA: HDD28 when the composition ratio of methyl acrylate in the copolymer is 22% by weight) or a mixture of these with low density polyethylene.

  Further, in the web preparation of the nonwoven fabric wiper of the present invention, a conventionally well-known web forming technique such as a dry method or a wet method can be used, and a needle punch method, a high-pressure water current junction is used for the purpose of ensuring fiber strength according to the design. Various entanglement techniques can also be used together. Among these, for example, when the HDD is lower than the above-mentioned EMA, the dust trapping efficiency is improved, but the passability of the card machine that is preferably used from the viewpoint of productivity when preparing the nonwoven fabric wiper is also reduced, and the fiber web May cause neps. In such a case, the use of a thermoplastic resin composed of a mixture of EMA and LDPE or EVA, or the weight ratio of the constituent fiber in the non-woven wiper and the above-mentioned heat fusion fiber is 80/20 to 35/65. The range is preferable. Among these, when the predetermined composition fiber is excessively blended with a fiber composition weight ratio exceeding 80/20, it is possible to ensure the card machine passability, but on the other hand, it is expected to improve the dust trapping efficiency by the heat-sealing fiber. Becomes difficult. In addition, when the composition ratio is less than 35/65 as the weight ratio, the dust capturing efficiency is excellent, but the slip resistance at the time of wiping is increased, and it is difficult to ensure the above-described card machine passability. .

  Next, other preferred embodiments will be described as constituent fibers in the nonwoven fabric wiper of the present invention. Various fibers can be used as the constituent fiber of the present invention, but by blending a part of the fibers as a latent crimpable fiber and producing a highly crimped fiber that has been crimped by a predetermined heat treatment, In addition to the captured dust, soil having a relatively large particle size can also be captured. The high-crimped fibers mentioned here are crimps of single fibers that are generally considered to have good carding properties by the method described in “8.12 Crimping” of JIS L1015 “Chemical Fiber Staple Test Method”. The fiber component contained in a nonwoven fabric wiper in the state more than several 9-20 pieces / 25mm. As the preferred high-crimped fibers, the latent crimps that have the above-described general number of crimps at the time of web preparation and become a large number of crimps of, for example, 50 pieces / 25 mm or more after heat treatment at a predetermined temperature. It is most suitable to use a natural fiber. By adopting such a latent crimpable fiber after the expression of crimp as a constituent fiber, in addition to the wipeability of dust having a relatively small particle size due to the tackiness of the heat-sealing fiber, which is the main feature of the present invention, comparison Capability to capture soil with a large particle size can also be exhibited.

  In the above description, the case where the predetermined constituent fiber and the predetermined heat-sealable fiber are used has been described. However, the above-described predetermined heat-sealable fiber is used as the fiber layer constituting the surface of the nonwoven fabric wiper. In this case, the fiber layer may be laminated with another constituent component that becomes a support such as a spunbond nonwoven fabric or a mesh sheet disclosed in Patent Document 2.

  Hereinafter, examples of the nonwoven fabric wiper of the present invention will be described. In the following description, specific numerical conditions and the like are shown to the extent that the present invention can be easily understood. However, the present invention is not limited only to these conditions, and various modifications can be made within the scope of the object of the present invention. Modifications and changes can be made.

Example 1
First, as a wiper according to Example 1 of the present invention, an ethylene-vinyl acetate copolymer (melting point: 97.6 ° C., composition ratio of vinyl acetate in copolymer: 6% by weight, HDD 43) is used as a sheath, and a core is formed. 40% by weight of a core-sheath type heat-sealing fiber “Daiwabo NBF SE” (trade name, manufactured by Daiwa Boseki Co., Ltd., fineness 3.3 decitex × fiber length 45 mm) composed of polyethylene terephthalate, Polyethylene terephthalate fiber “Toray Tetron T-209” (trade name, manufactured by Toray Industries, Ltd., fineness 3.3 decitex × fiber length 64 mm, number of crimps about 11/25 mm), 40% by weight, and other constituent fibers Polyethylene terephthalate highly crimped fiber “Toray Tetron T-12” (trade name, manufactured by Toray Industries, Inc., fineness 3.3 decitex × fiber length 51 mm, crimped number of about 1 Pieces / 25 mm) 20% by weight, uniformly cotton mixing, after the web is formed by carding machine, a cross-lay web was prepared by crossing angle 30 °. Next, after needle punching was performed on this web at a needle density of 50 / cm ² , fiber bonding was performed by heating for about 1 minute in a hot air drier at a temperature of 120 ° C., and a surface density of 60 g. / woven fabric was obtained wiper according to a first embodiment of m ^2.

(Example 2)
The heat-sealing fiber in Example 1 described above was made of an ethylene-methyl acrylate copolymer (melting point: 92.0 ° C., composition ratio of methyl acrylate in copolymer: 22% by weight, HDD 28) with a sheath and a core with polypropylene. The other two constituent fibers were blended and mixed uniformly, except for the arrangement “Daiwabo NBF XG” (trade name, manufactured by Daiwabo Co., Ltd., fineness 2.2 decitex × fiber length 45 mm). After that, the web was formed with a card machine under the same conditions as in Example 1, cross-lay, and needle punch, and then heat-treated with a hot air drier for 3 minutes at a temperature of 110 ° C. to achieve an areal density of 60 g / m ² . The nonwoven fabric wiper according to Example 2 was obtained.

(Example 3)
In the nonwoven fabric wiper according to Example 3, an ethylene-vinyl acetate copolymer (melting point: 97.6 ° C., composition ratio of vinyl acetate in the copolymer: 6% by weight, HDD 43) as a core-sheath type heat-sealing fiber; “Chissopolypro EAC021” (trade name, fineness 2.2 decitex x fiber manufactured by Chisso Corp.) with sheath formed as a mixture with low density polyethylene (melting point 110 ° C., HDD50) and polypropylene in the core 38 mm long) was used. The thermoplastic resin constituting the sheath portion of the heat-sealing fiber has an HDD 47 and a melting point of 104 ° C. 30% by weight of such a heat-sealing fiber was blended with 70% by weight of the polyethylene terephthalate fiber “Toray Tetron T-209” (trade name, manufactured by Toray Industries, Inc.) among the constituent fibers used in Example 1. . Then, the nonwoven fabric wiper which concerns on Example 3 of the surface density of 60 g / m < ² > was obtained on the same various conditions as Example 1 except having set the temperature conditions of the fiber bonding in fiber bonding to 110 degreeC.

Example 4
30% by weight of heat-sealing fiber “Daiwabo NBF SE” (trade name, manufactured by Daiwa Boseki Co., Ltd.) used in Example 1, and polyethylene terephthalate fiber “Toray Tetron T-209” (trade name, manufactured by Toray Industries, Inc.) ) A non-woven wiper according to Example 4 having an areal density of 60 g / m ² was prepared under the same conditions as in Example 1 except that 70% by weight was uniformly mixed.

(Example 5)
60% by weight of the heat-sealing fiber “Daiwabo NBF SE” (trade name, manufactured by Daiwabo Co., Ltd.) of Example 4 described above, and polyethylene terephthalate fiber “Toray Tetron T-209” (trade name, manufactured by Toray Industries, Inc.) ) A non-woven wiper according to Example 5 having a surface density of 60 g / m ² was prepared under the same conditions as in Example 1 and Example 4 except that 40% by weight was blended.

(Example 6)
In the nonwoven fabric wiper according to Example 6, as a sheath-core type heat-fusible fiber, an ethylene-methyl acrylate copolymer (melting point: 92.0 ° C., composition ratio of methyl acrylate in copolymer: 22% by weight, HDD 28) is sheathed. 70 parts by weight of “Daiwabo NBF XG” (trade name, fineness 2.2 decitex × fiber length 45 mm, manufactured by Daiwa Boseki Co., Ltd.), which is made up of polypropylene at the core, is used in Example 1. The mixed fiber “Toray Tetron T-209” (trade name, manufactured by Toray Industries, Inc.) 30% by weight was blended. Thereafter, a nonwoven fabric wiper according to Example 6 having an areal density of 60 g / m ² was obtained under the same conditions as in Example 1 except that the temperature condition of fiber-to-fiber bonding in fiber-to-fiber bonding was 110 ° C.

(Example 7)
In the nonwoven fabric wiper according to Example 7, 20% by weight of the heat-sealing fiber “Daiwabo NBF SE” (trade name, manufactured by Daiwa Boseki Co., Ltd.) used in Example 1, and commercially available latent crimpable fibers. “Toray Tetron T-25” (trade name, manufactured by Toray Industries, Ltd., fineness 2.2 decitex × fiber length 51 mm, number of crimps before heat treatment of about 16 pieces / 25 mm) 40% by weight, used in Example 1 Constituent fiber “Toray Tetron T-209” (trade name, manufactured by Toray Industries, Inc.) 40% by weight was uniformly mixed, a web was prepared by a card machine, and needle punching was performed under the same conditions as in each of the previous examples. . Thereafter, the web was subjected to heat shrinkage treatment for 2 minutes in a hot air dryer at a temperature of 150 ° C. so that the above-described latent crimped fiber was made into a highly crimped fiber, and Example 7 having an areal density of 60 g / m ^2. The nonwoven fabric wiper according to the present invention.

(Example 8)
In the nonwoven fabric wiper according to Example 8, in the constituent fibers of Example 7 described above, “Toray Tetron T-25” (trade name, manufactured by Toray Industries, Inc.) 30% by weight, which is a latent crimpable fiber, A non-woven wiper was prepared using the same heat-sealable fiber as in Example 7 except that it was 50% by weight of the constituent fiber “Toray Tetron T-209” used in No. 1.

(Comparative Example 1)
As the nonwoven fabric wiper according to Comparative Example 1, a wiper to which the technology according to Patent Document 1 described above was applied was prepared. First, a commercially available latent crimpable fiber “Unitika Ester C-81” (trade name, manufactured by Unitika Ltd., fineness of 2.8 decitex × fiber length of 51 mm, which is a side-by-side arrangement of polyethylene terephthalate and modified polyethylene terephthalate, heat treatment Using only the previous crimp number of about 11 pieces / 25 mm), two sheets of webs to be the surface layer having a surface density of about 17 g / m ² were prepared by a card machine. Next, high-density polyethylene (melting point: 130 ° C., HDD63) is placed in the sheath and polypropylene is placed in the core, and the heat-sealed fiber “Chisso Polypro ESC” (trade name, fineness 3.3 decitex manufactured by Chisso Corporation) X fiber length 64 mm) alone was used to prepare a card web that would be an intermediate layer with an areal density of about 17 g / m ² . Next, a three-layer structure in which the intermediate layer is sandwiched between the surface layers so that these two types of webs have a crossing angle of 30 ° with each other, needle punching is performed under the same conditions as in the above-described embodiments, and then the temperature condition 150 ℃ by heating shrinking treatment for 1 minute in a hot air dryer, the latent crimp fibers described above as high crimp fibers, and a nonwoven fabric wiper according to Comparative example 1 of surface density 60 g / m ^2.

(Comparative Example 2)
As the nonwoven fabric wiper according to Comparative Example 2, 30% by weight of the heat-sealing fiber “Chisso Polypro ESC” (trade name, manufactured by Chisso Corporation) used in Comparative Example 1, and the constituent fiber “Toray Tetron T-209” (Toray Industries, Inc.) A fiber web having a structure of only one layer was prepared by uniformly blending 70% by weight with a product name (manufactured by Co., Ltd.). Subsequently, heat treatment was performed with a needle punch and a hot air dryer under the same conditions as in Comparative Example 1, and a non-woven wiper with a surface density of 60 g / m ^{2 according} to Comparative Example 2 was obtained.

(Comparative Example 3)
As Comparative Example 3, the surface density was 60 g / m ^{2 under} the same conditions as Comparative Example 2 except that the weight ratio of the fiber blend of Comparative Example 2 was 60% by weight of the heat-fusible fiber and 40% by weight of the constituent fiber. A non-woven wiper was obtained.

  Table 1 shows the evaluation results regarding the fiber composition of the series of nonwoven fabric wipers described above and the card machine passability. In the table, for the heat-bonding fiber in the fiber composition, the abbreviation of the thermoplastic resin and the measured value of the HDD are the names of the thermoplastic resin, and the weight ratio (% by weight) in the non-woven wiper is shown. The above-mentioned weight ratio is similarly indicated by the fiber name. Moreover, the card machine passability is determined by observing the presence or absence of nep and thickness uniformity that can be found with the naked eye in a non-woven wiper of about 1 meter square. The case where some neps and unevenness were observed and there was no problem in use, but the appearance was slightly inferior was evaluated as Δ.

  Next, the results of performing and evaluating the wiping test using each of the above-described nonwoven fabric wipers as samples will be described. In this evaluation test, 3.00 g of each of the following two types of test powders was sprayed on a 30 cm wide strip on an epoxy-coated floor surface that was previously cleaned and cleaned of dust and the like. The above-mentioned wiper applicator “Bond Polbeck Applicator P-45” (trade name manufactured by Konishi Co., Ltd., mounting surface dimensions corresponding to the wiper wiping surface is a trapezoid having an upper side of 560 mm, a lower side of 515 mm, and a height of 87 mm). Each sample was mounted and wiped back and forth 15 times in the shape of a figure 8 in a 1.5 m square floor including the floor on which the test powder was dispersed. The amount collected was calculated from the sample weight before and after the measurement.

(1) JIS type 2 test powder (particle size 5 to 75 μm: equivalent to dust)
(2) JIS type test powder (particle size 45 to 300 μm: equivalent to earth and sand)

  In addition, a series of wiping tests were performed under conditions of 22 to 30 ° C. and relative humidity of 35%. Table 2 shows the respective trapping amounts corresponding to the above test results for each sample.

  As can be understood from Table 2 and Table 1 described above, the nonwoven fabric wipers of Examples 1 to 8 adopted HDD 55 or less as the thermoplastic resin exposed on the surface of the heat-sealing fiber. Compared with Comparative Examples 1 to 3 in which an HDD having a size larger than 55 was used, it was confirmed that the amount of dust captured was excellent because of having a kind of tackiness. Further, from Example 6, the amount of dust trapping tends to increase as the blending amount of the fibers below HDD 55 increases, but each of Examples 4 and 5 or Examples 4 and 6 is compared. As can be understood from the figure, a decrease in the card machine passability was confirmed as the blending amount of the heat-fusible fiber was increased. Therefore, from the observations in Example 5 and Example 6, in order to satisfy both the dust capturing performance and the productivity of the nonwoven fabric, the ratio of the heat-sealing fibers satisfying the requirements of the HDD according to the present invention to the nonwoven fabric wiper is About 65% by weight or less.

  In Examples 7 and 8 and Comparative Example 4, the same heat-sealing fiber having an HDD of 55 or less was fixed at 20% by weight, and the high concentration derived from the latent crimpable fibers in the constituent fibers. A wiper in which only the weight ratio of crimped fibers is changed. From these comparisons, it was confirmed that the amount of both earth and sand trapped gradually decreased as the weight ratio of the highly crimped fibers was decreased. In particular, in Comparative Example 4, although the above-described prior art comparative example 1 wiper and earth and sand trapping amount were excellent results, the dust trapping amount was equal. From this, it can be understood that the weight ratio of the highly crimped fibers in the constituent fibers of the present invention, that is, the crimped latent crimpable fibers may be 30% by weight or more.

Claims (5)

In the nonwoven fabric wiper in which the constituent fiber and the heat-sealing fiber are bonded to each other, the thermoplastic resin constituting the heat- sealing fiber is exposed on the surface of the heat- sealing fiber and has a durometer hardness of 55 or less. Non-woven wiper characterized by having a thickness (HDD). The nonwoven fabric wiper according to claim 1, wherein the thermoplastic resin constituting the heat-sealing fiber is made of a polyethylene copolymer. The polyethylene copolymer constituting the heat-bonding fiber is one or two selected from ethylene-vinyl acetate copolymer (EVA), ethylene-methyl acrylate copolymer (EMA), and low density polyethylene (LDPE). The nonwoven fabric wiper according to claim 2, which is a mixture of the above. The nonwoven fabric wiper according to any one of claims 1 to 3, wherein a weight ratio between the constituent fibers and the heat-sealing fibers is in a range of 80/20 to 35/65. The nonwoven fabric wiper according to claim 4, wherein the constituent fibers include highly crimped fibers in which latent crimpable fibers are crimped by heat treatment.