WO2009082136A1

WO2009082136A1 - A cloth for knitting having microfiber

Info

Publication number: WO2009082136A1
Application number: PCT/KR2008/007551
Authority: WO
Inventors: Tae Hyeong Kim
Original assignee: Woongjin Chemical Co., Ltd.
Priority date: 2007-12-21
Filing date: 2008-12-19
Publication date: 2009-07-02
Also published as: CN101903578B; CN101903578A

Abstract

Disclosed are knitted cloth containing microfibers. The knitted cloth comprise ground yarns for shape stability and pile yarns forming unit regions. The unit regions are formed in a repeating manner. Each of the unit regions includes two or three regions composed of different materials. In an exemplary embodiment, each of the unit regions includes at least one region containing mi¬ crofibers to offer cleaning performance, wiping performance and absorbency and at least one region allowing the knitted fabric to be easily pushed. The microfiber-containing knitted cloth stably pick up dust and impurities and prevent the picked-up dust and impurities from escaping. Therefore, the microfiber-containing knitted cloth exhibit good cleaning performance.

Description

A CLOTH FOR KNITTING HAVING MICROFIBER

Technical Field

[1] The present invention relates to microfiber-containing knitted cloth for use in cleaning elements such as cleaning pads. More specifically, the present invention relates to microfiber-containing knitted cloth with good cleaning performance that are easily pushed without the need for a large force of a user upon cleaning and that can stably pick up dust and impurities and prevent the picked-up dust and impurities from escaping.

[2]

Background Art

[3] Fiber-made cleaning pads and cleaning implements have been used for the purpose of cleaning rooms, floors and glass in houses and offices. For example, a cleaning pad is attached to a push stick before cleaning and absorbs an appropriate amount of water for ease of cleaning. After cleaning, the cleaning pad is separated from the push stick, washed, dried, and stored. In recent years, many convenient-to-use cleaning instruments have been developed and emerged in the market. Particularly, Velcro is used to easily removably attach a cleaning pad to a push stick to improve the convenience of use.

[4] A number of cleaning pads using microfibers are currently commercially available.

The use of a microfiber in a cleaning pad increases the contact area between the cleaning pad and a surface to be cleaned to increases the ability of the cleaning pad to pick up dust and dirt and prevent the picked-up dust and dirt from escaping from the cleaning pad, resulting in an increase in cleaning efficiency. NP split-type composite yarns composed of nylon and polyester have hitherto been used as cleaning microfibers.

[5] Korean Patent No. 257806 suggests a method for manufacturing a cleaning cloth by air-blending and interlacing polyester filament microfibers, in which microfibers having various finenesses ranging from 0.06 to 0.5 denier coexist, with polyester high shrinkage yarns having a dry heat shrinkage of 25 to 35%, knitting the interlaced products, and making the filament microfibers finer. The cleaning cloth is advantageous in removing dust or dirt. However, the microfibers of the cleaning cloth are liable to be worn out due to their low strength when the cleaning cloth is repeatedly pushed and pulled during cleaning, thus making the user exhausted.

[6] In an attempt to overcome the above disadvantages, Korean Unexamined Patent

Publication No. 2003-94342 proposes a microfiber cleaning cloth knitted with a pattern comprising a piqu knitting pattern. The cleaning cloth exhibits good cleaning performance despite reduced frequency of push and pull movements, but has the disadvantage of poor durability arising from the use of the microfibers and limitation in removing long-standing dirt by a small force.

[7]

Disclosure of Invention Technical Problem

[8] It is an objectof the present invention to solve the above problems and provide microfiber-containing knitted cloth with good cleaning performance that can be used for cleaning with high efficiency by a small force.

[9]

Technical Solution

[10] According to one embodiment of the present invention, there is provided a microfiber-containing knitted cloth which comprises ground yarns for shape stability and pile yarns forming unit regions wherein each of the unit regions includes 64 to 84% by weight of first regions containing microfibers to offer cleaning performance, wiping performance and absorbency, 10 to 30% by weight of second regions allowing a pad to be easily pushed and 6 to 16% by weight of a third region serving to sweep dust or dirt, and the unit regions are formed in a repeating manner.

[11] Each of the unit regions may have a configuration in which the first region, the second region, the first region, the second region and the third region are arranged in this order.

[12] The first region, the second region, the first region, the second region and the third region may be present in a weight ratio of 32-42 : 5-15 : 32-42 : 5-15 : 6-16 in each of the unit regions.

[13] Each of the unit regions may be formed by weaving such that the pile lengths of the first, second and third regions decrease in the order: the second regions > the third region > the first regions.

[14] The first regions may be composed of twisted yarns that contain draw textured yarns containing polyester filament yarns having a total fineness of 100 to 400 D.

[15] The second regions may be composed of twisted yarns that contain polyester textured yarns having a total fineness of 100 to 200 D.

[16] The third region may be composed of poly olefin draw textured yarns having a total fineness of 300 to 600 D.

[17] According to another embodiment of the present invention, there is provided a microfiber-containing knitted fabric which comprises ground yarns for shape stability and pile yarns forming unit regions wherein each of the unit regions includes 62 to 75% by weight of region A containing split yarns as microfibers to offer cleaning performance, wiping performance and absorbency and 25 to 38% by weight of region

B to allow the knitted fabric to be easily pushed, and the unit regions are formed in a repeating manner.

[18] The microfibers may be nylon/polyester (NP) split yarns.

[19] Each of the unit regions may be formed by weaving such that the pile length of the region A is greater than that of the region B. [20] The region A may be composed of twisted yarns having a total fineness of 100 to 400

D. [21] The region B may be composed of twisted yarns that contain polyester textured yarns having a total fineness of 100 to 200 D.

[22] The unit regions may be formed in a linear or wave-like pattern.

[23] The wave-like pattern may be a waveform, pulse- wave or zigzag pattern.

[24] The ground yarns may contain high stretch yarns having a total fineness of 100 to

200 D. [25] The high stretch yarns may be selected from the group consisting of spandex, elastic yarns, latent self crimping yarns, mechanical crimping yarns, and combinations thereof. [26] The ground yarns may be selected from the group consisting of polyurethane fibers, polyester fibers, acrylic fibers, and combinations thereof. [27] The knitted fabric may be pushed and pulled at a pressure of 0.50 to 0.55 Ib and a tension of 0.60 to 0.80 Ib in a dry state (moisture content < 5%) on a floor inclined at an angle of 30° relative to the knitted fabric. [28] The knitted fabric may be pushed and pulled at a pressure of 2.30 to 2.50 Ib and a tension of 4.90 to 5.20 Ib in a dry or wet state on a floor inclined at an angle of 60° relative to the knitted fabric when a weight of 3.5 Ib is added thereto.

[29] The knitted fabric may have a dust removal efficiency of 99% or above in a wet state.

[30] According to yet another embodiment of the present invention, there is provided a cleaning pad comprising a pad layer formed of one of the knitted cloth, an absorbing layer attached to the back surface of the pad layer and formed of a foamed polymer, a sponge or a non- woven fabric web to absorb moisture or oil, and a removable layer attached to the back surface of the absorbing layer and including Velcro, a button, a zipper or strings to offer the convenience of washing.

Advantageous Effects

[31] As describe above, the microfiber-containing knitted cloth of the present invention are produced by forming two or three regions with different functions in a linear or wave-like pattern by weaving. The microfiber-containing knitted cloth of the present invention can thoroughly remove dust or dirt by rubbing and wiping despite reduced frequency of push and pull movements. In addition, the microfiber-containing knitted cloth of the present invention require less force for cleaning and are highly durable.

[32] Furthermore, the microfiber-containing knitted cloth of the present invention are easy to wash and can easily remove picked-up dirt therefrom upon washing with water.

[33]

Brief Description of Drawings

[34] FIG. 1 is a plan view of a microfiber-containing knitted fabric according to one embodiment of the present invention;

[35] FIG. 2 is a plan view of a microfiber-containing knitted fabric according to another embodiment of the present invention;

[36] FIG. 3 shows patterns of cleaning pad piles (a)-(d) according to preferred embodiments of the present invention; and

[37] FIG. 4 is a cross-sectional view of a cleaning mat according to a preferred embodiment of the present invention.

[38] <Brief explanation of essential parts of the drawings>

[39] 10: Cleaning pad 11 : Pad layer

[40] 13: Absorbing layer 15: Removable layer

[41] 20: Support 110: First regions

[42] 120: Second regions 130: Third region

[43] 210: Regions A 220: Regions B

[44]

Best Mode for Carrying out the Invention

[45] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that whenever possible, the same reference numerals will be used throughout the drawings and the description to refer to the same or like parts. In describing the present invention, detailed descriptions of related known functions or configurations are omitted in order to avoid making the essential subject of the invention unclear.

[46] As used herein, the terms "aboutP", "substantially", etc. are intended to allow some leeway in mathematical exactness to account for tolerances that are acceptable in the trade and to prevent any unconscientious violator from unduly taking advantage of the disclosure in which exact or absolute numerical values are given so as to help understand the invention.

[47] The microfiber-containing knitted cloth of the present invention will be described in connection with cleaning pads, but their use is not limited thereto.

[48] Microfibers used in the present invention have a fineness of 0.5 denier (D) or less. The microfibers may be selected from the group consisting of filament yarns, sea island yarns, split yarns such as nylon/polyester (NP) split yarns and polyester/ polypropylene (PP) split yarns, etc. The microfibers may be produced by any suitable process.

[49] FIGS. 1 and 2 are plan views of microfiber-containing knitted cloth according to embodiments of the present invention.

[50] Each of the microfiber-containing knitted cloth comprises ground yarns for shape stability and pile yarns forming unit regions.

[51] As illustrated in FIGS. 1 and 2, each of the unit regions may include two or three divided regions.

[52] The unit regions illustrated in FIG. 1 are formed in a repeating manner, each of which includes three regions composed of different pile materials. Specifically, each unit region may include first regions 110, second regions 120 and a third region 130.

[53] In each unit region, the first regions 110 are present in an amount of 64 to 84% by weight, the second regions 120 are present in an amount of 10 to 30% by weight, and the third region 130 is present in an amount of 6 to 16% by weight. Each of the unit regions may be formed in a loop pile or cut-loop pile pattern by weaving such that the lengths of the regions decrease in the order: the second regions 120 > the third region 130 > the first regions 110.

[54] Each of the unit regions may have a configuration in which the first region 110, the second region 120, the first region 110, the second region 120 and the third region 130 are arranged in this order. The unit regions are formed in a linear or wave-like pattern. The first region 110, the second region 120, the first region 110, the second region 120 and the third region 130 may be present in a weight ratio of 32-42 : 5-15 : 32-42 : 5-15 : 6-16 in each of the unit regions.

[55] The first regions 110 are preferably composed of twisted yarns having a total fineness of 100 to 400 D, which are produced using microfibers having a fineness of 0.5 denier or less. Most preferably, the first regions 110 are composed of twisted yarns that contain draw textured yarns (DTYs) containing chemical-resistant polyester filament yarns. Particularly, each of the twisted yarns is produced by twisting two strands of draw textured yarns containing PET filament yarns (170 /72 ) and one strand of a PET twisted yarn (150 /288 ). The twisted yarns are microfibers with good absorbency, tactile feeling and wiping performance.

[56] If the first regions 110 are present in an amount of less than 64% by weight, there is the risk that the wiping performance or absorbency of the knitted fabric may deteriorate. Meanwhile, if the first regions 110 are present in an amount of more than 84% by weight, an additional pushing force may be needed upon wiping and the durability of the knitted fabric may be poor. [57] The second regions 120 may be composed of twisted yarns that contain polyester textured yarns having a total fineness of 100 to 200 D. Particularly, each of the twisted yarns is produced by twisting three strands of polyester draw textured yarns (150 /48 ). The twisted yarns allow a pad to be easily pushed upon cleaning, prevent picked-up dust or dirt from escaping, and protect the arrangement of lines of the piles from being disordered. If the second regions 120 are present in an amount of less than 10% by weight, the arrangement of the piles of the first regions 110 is not maintained ordered, leading to an increase in the frequency of push and pull movements for wiping. Meanwhile, if the second regions 120 are present in an amount exceeding 30% by weight, there is the risk that the wiping performance and absorbency of the knitted fabric may deteriorate.

[58] The third region 130 is composed of polyolefin draw textured yarns having a total fineness of 300 to 600 D. Polypropylene (PP) twisted yarns (450 /15 ) are particularly preferred. The third region 130 imparts strength to the knitted fabric due to its rigidity and serves as a broom to effectively sweep and rub off dirt, thus enabling the removal of dust or dirt without the need for a large force upon rubbing and wiping despite reduced frequency of push and pull movements. In addition, the third region 130 improves the durability of the knitted fabric. If the third region 130 is used in an amount of less than 6% by weight, the pile strength is lowered, resulting in an increase in the rubbing frequency. As a result, a larger force is necessary for cleaning and a decrease in durability is caused. Meanwhile, if the third region 130 is used in an amount of more than 16% by weight, the surface layer is rigid, thus increasing the risk of damage to a cleaning article using the knitted fabric, and a portion of picked-up dust, dirt or solution remains unremoved, thus increasing the risk that the cleaning performance of the knitted fabric may be lowered.

[59] Preferably, the lengths of the first, second and third regions 110, 120 and 130 decrease in the order: the second regions 120 > the third region 130 > the first regions 110. Due to the difference in the length of the regions, the second regions 120 allow a pad to be easily pushed, the third region 130 collects dust or oil, and the first regions 110 absorb the dust or oil and prevent the picked-up dust or oil from escaping.

[60] Referring to FIG. 2, the microfiber-containing knitted fabric comprises unit regions formed in a repeating manner, each of which includes two divided regions. Specifically, each unit region may include region A 210 and region B 220 composed of different material piles.

[61] The region A 210 and the region B 220 are present in amounts of 62 to 75% by weight and 25 to 38% by weight, respectively. Each of the unit regions may be formed in a loop pile or cut- loop pile pattern by weaving such that the pile length of the region A is greater than that of the region B. [62] The region A 210 is preferably composed of twisted yarns having a total fineness of

100 to 400 D, which are produced using microfibers having a fineness of 0.5 denier or less. Most preferably, the region A 210 is composed of twisted yarns that contain draw textured yarns (DTYs) containing nylon/polyester (NP) split- type composite yarns. Particularly, each of the twisted yarns is produced by twisting two or three strands of nylon/polyester (NP) draw textured yarns (150^D/72^F). The twisted yarns are microfibers with good absorbency, tactile feeling and wiping performance.

[63] If the region A 210 is present in an amount of less than 62% by weight, there is the risk that the wiping performance or absorbency of the knitted fabric may deteriorate. Meanwhile, if the region A 110 is present in an amount of more than 75% by weight, an additional pushing force may be needed upon wiping and the durability of the knitted fabric may be poor.

[64] The region B 220 may be composed of twisted yarns that contain polyester textured yarns having a total fineness of 100 to 200 D. Particularly, each of the twisted yarns is produced by twisting two or three strands of polyester draw textured yarns (150 /48 ). The twisted yarns allow the knitted fabric to be easily pushed upon cleaning, prevent picked-up dust or dirt from escaping, and protect the arrangement of lines of the piles from being disordered. If the region B 220 is present in an amount of less than 25% by weight, the arrangement of the piles of the region A 210 is not maintained ordered, leading to an increase in the frequency of push and pull movements for wiping. Meanwhile, if the region B 220 is present in an amount exceeding 38% by weight, there is the risk that the wiping performance and absorbency of the knitted fabric may deteriorate.

[65] The ground yarns preferably contain high stretch yarns having a total fineness of 100 to 200 D. The high stretch yarns may be selected from the group consisting of spandex, elastic yarns, latent self crimping yarns, mechanical crimping yarns, and combinations thereof. The ground yarns may be selected from the group consisting of polyurethane fibers, polyester fibers, acrylic fibers, and combinations thereof. It is particularly preferred that the ground yarns contain high stretch polyethylene terephthalate yarns.

[66] The microfiber-containing knitted fabric is pushed and pulled at a pressure of 0.50 to

0.55 Ib and a tension of 0.60 to 0.80 Ib in a dry state (moisture content < 5%) on a floor inclined at an angle of 30° relative to the knitted fabric. Further, the knitted fabric is pushed and pulled at a pressure of 2.30 to 2.50 Ib and a tension of 4.90 to 5.20 Ib in a dry state or a wet state, in which the knitted fabric contains a cleaning solution whose weight is 2.00 to 2.50 times greater than that of the knitted fabric in a dry state, on a floor inclined at an angle of 60° relative to the knitted fabric when a pressure of 3.5 Ib is applied thereto.

[67] The microfiber-containing knitted fabric has a dust removal efficiency of 99% or above in a wet state in which the knitted fabric contains a cleaning solution whose weight is 2.00 to 2.50 times greater than that of the knitted fabric in a dry state.

[68]

[69] FIG. 3 shows patterns of cleaning pad piles (a)-(d) according to preferred embodiments of the present invention.

[70] In the linear pattern of FIG. 3(a), the respective regions are regularly arranged to achieve good wiping performance. The wave-like pattern of FIG. 3(c) and (d) may be a waveform, pulse- wave or zigzag pattern. The piles in a wave-like pattern increase the contact area between the cleaning pad and a surface to be cleaned to decrease the frequency of push and pull movements and the force necessary for rubbing and wiping, resulting in a marked improvement in the wiping performance and cleaning performance of the knitted fabric.

[71] FIG. 4 is a cross-sectional view of a cleaning mat according to a preferred embodiment of the present invention. Referring to FIG. 4, the cleaning mat 10, which is a cleaning article that can be manufactured using one of the microfiber-containing knitted cloth according to the embodiments of the present invention, is detachably attached to a support 20, and may comprise a pad layer 11, an absorbing layer 13 and a removable layer 15. The pad layer 11 is in direct contact with a floor or an area to be cleaned and may be composed of one of the microfiber-containing knitted cloth according to the embodiments of the present invention. The pad layer 11 may be formed in a loop pile or cut-loop pile pattern to optimize the cleaning performance of the cleaning mat 10. The pile pattern is advantageous in cleaning performance. In addition, another advantage of the pile pattern is high resilient elasticity, which allows the piles to be raised and offers good cushiony and tactile feeling.

[72] The absorbing layer 13 may be formed on one surface of the removable layer 15. The absorbing layer 13 may be formed of a foamed polymer, a sponge or a non- woven fabric web to absorb moisture or oil. The removable layer 15 may be formed on one surface of the absorbing layer 13 and may include Velcro, a button, a zipper or strings for attachment/detachment to offer the convenience of washing.

[73] The cleaning mat 10 can be manufactured by sequentially laminating the pad layer, the absorbing layer and the removable layer, sewing the laminate as a whole, and finishing the edges of the laminate.

[74] Each of the microfiber-containing knitted cloth is pushed and pulled at a pressure of

0.50 to 0.55 Ib and a tension of 0.60 to 0.80 Ib in a dry state (moisture content < 5%) on a floor inclined at an angle of 30° relative to the knitted fabric. Further, each of the knitted cloth is pushed and pulled at a pressure of 2.30 to 2.50 Ib and a tension of 4.90 to 5.20 Ib in a dry state or a wet state, in which the knitted fabric contains a cleaning solution whose weight is 2.00 to 2.50 times greater than that of the knitted fabric in a dry state, on a floor inclined at an angle of 60° relative to the knitted fabric when a pressure of 3.5 Ib is applied thereto.

[75] Each of the microfiber-containing knitted cloth has a dust removal efficiency of 99% or above in a wet state in which the knitted fabric contains a cleaning solution whose weight is 2.00 to 2.50 times greater than that of the knitted fabric in a dry state.

[76]

[77]

Mode for the Invention

[78] Hereinafter, the present invention will be explained in more detail with reference to the following examples.

[79]

[80] EXAMPLES

[81] Example 1

[82] A pad layer was composed of a microfiber-containing knitted fabric. An absorbing layer was formed on the back surface of the pad layer. The absorbing layer was formed of a three-dimensional low-density non- woven fabric web. A Velcro sheet as a removable layer was formed on the back surface of the absorbing layer. The laminate was sewn as a whole and its edges were finished to complete the manufacture of a rectangular cleaning mat. The microfiber-containing knitted fabric was comprised of ground yarns and pile yarns forming unit regions. High stretch PET draw textured yarns (150 /48 ) were included in the ground yarns. 66% by weight of first regions, 22% by weight of second regions and 12% by weight of a third region were included in each of the unit regions. The first regions were composed of twisted yarns, each of which was produced by twisting two strands of PET filament draw textured yarns (170 /72 ) as microfibers and one strand of a PET twisted yarn (150 /288 ). The second regions were composed of twisted yarns, each of which was produced by twisting three strands of PET draw textured yarns (150 /48 ). The third region was composed of PP twisted yarns (450 /15 ). Each of the unit regions was formed in a loop pile pattern by weaving. In each of the unit regions, the first region had six lines, the second region had two lines, the first region had six lines, the second region had two lines and the third region had two lines. That is, the weight ratio of the first region: the second region: the first region: the second region: the third region = 33.5 : 11 : 33.5 : 11 : 11. The unit regions were formed in a zigzag pattern and in a repeating manner by weaving such that the pile lengths of the first, second and third regions decreased in the order: the second regions > the third region > the first regions. The final knitted fabric had a weight of 590 g/sm.

[83] [84] Example 2

[85] A pad layer was composed of a microfiber-containing knitted fabric. An absorbing layer was formed on the back surface of the pad layer. The absorbing layer was formed of a three-dimensional low-density non- woven fabric web. A Velcro sheet as a removable layer was formed on the back surface of the absorbing layer. The laminate was sewn as a whole and its edges were finished to complete the manufacture of a rectangular cleaning mat. The microfiber-containing knitted fabric was comprised of ground yarns and pile yarns forming unit regions. High stretch PET draw textured yarns (150 /48 ) were included in the ground yarns. 72% by weight of region A and 28% by weight of region B were included in each of the unit regions. The region A was composed of twisted yarns, each of which was produced by twisting two strands of nylon/polyester (NP) draw textured yarns (150 /72 ) as microfibers. The region B was composed of twisted yarns, each of which was produced by twisting three strands of PET draw textured yarns (150 /48 ). The unit regions were formed in a zigzag pattern illustrated in FIG. 2 as a loop pile pattern and in a repeating manner by weaving such that the pile length of the region A was greater than that of the region B. The final knitted fabric had a weight of 570 g/sm.

[86]

[87] Comparative Example 1

[88] The procedure of Example 1 was repeated, except that the pad layer was composed of PP split yarns and the ground yarns were polyester yarns.

[89]

[90] Comparative Example 2

[91] The procedure of Example 1 was repeated, except that the pad layer was composed of nylon/PET split yarns (80^D/20^F) as microfibers and the ground yarns were polyester yarns.

[92]

[93] Comparative Example 3

[94] Microfiber pads (3M) were used.

[95]

[96] Comparative Example 4

[97] Microfiber pads (Johnson Diversity) were used.

[98]

[99] Comparative Example 5

[100] Microfiber pads (Tuway) were used.

[101]

[102] * Test methods

[103] 1. Drag Test [104] First, dry specimens of the cleaning mats were weighed. A mixed solution of a chlorinated cleaner (Quat, 3M 2 oz./l gallon water) was applied to a vinyl floor and wiped off with a ruff mate wiper. The remaining moisture and dust were wiped off with a microfiber pad. After each of the dry specimens was attached to a cleaning support, the cleaning mat was repeatedly pushed and pulled on the floor within two steps of a user in a state in which the cleaning mat was inclined at an angle 30° relative to the floor. The maximum pressure and tension on a gauge were recorded. Meanwhile, a weight of 3.5 Ib was applied to the cleaning support to incline the cleaning mat at an angle of 60° relative to the floor. The dry specimen was dipped in a solution of a chlorinated cleaner until the final weight of the specimen was about 2.26 times greater than the original weight. The wet specimen was weighed. Thereafter, the same test was conducted in a state in which the cleaning mat was inclined at an angle of 60°. In this test example, three specimens per sample were tested three times. The obtained values were averaged.

[105] Table 1 [Table 1] [Table ]

[106] [107] 2. Dust Test [108] First, dry specimens of the cleaning mats were weighed. An area of a vinyl floor to be tested was marked. A mixed solution of a chlorinated cleaner (Quat, 3M 2 oz./l gallon water) was applied to the test area of the floor and wiped off with a tuff mate wiper. The remaining moisture and dust were wiped off with a microfiber pad. After one ounce of dust was placed on the central portion of the test area, a dust spread box was installed outside the test area. A compressed air line and a nozzle were connected to the dust spread box, and air was sprayed downwardly toward the dust pile to allow the dust to be uniformly dispersed on the test area.

[109] About 5 minutes after the spraying until the dust was settled down on the floor, the level of the dust on the test area was measured. Thereafter, a test specimen having an adhesive attached to the back surface thereof as a standard sample was detached from a dust detector and placed on the floor. The surface of the test specimen was made smooth using a roller to allow the dust to be homogeneously attached to the test specimen. The test specimen was detached from the floor and put into the dust detector. The difference (%) in the weight of the test specimen before and after the cleaning was measured. Meanwhile, each of the dry specimens was dipped in a solution of a chlorinated cleaner until the final weight of the specimen was about 2.26 times greater than the original weight. After weighing, the wet specimen was mounted on a support, to which a weight of 3.5 Ib was applied. The specimen was pulled in a horizontal direction along the floor surface to wipe the floor. No vertical load was applied to the specimen. The level of the dust on the test area was recorded. After a new level of the dust was set, the same test was repeated. The obtained values are shown in Table 2.

[HO]

[111] Table 2

[Table 2] [Table ]

[112] [113] 3. Stain Test [114] First, dry specimens of the cleaning mats were weighed. A mixed solution of a chlorinated cleaner (Quat, 3M 2 oz./l gallon water) was applied to a vinyl floor and wiped off with a tuff mate wiper. The remaining moisture and dust were wiped off with a microfiber pad. Stained spots were obtained by the following procedure. Three drops of milk were dropped one by one on the floor in such a manner that the dropping locations were spaced at intervals of 6inch in a straight line. The size of the cleaning mat was 18inch, which was within one step of a user. Coke and ketchup were dropped at regular intervals of linch from the milk drops. The stains were dried for 4 hours. Meanwhile, each of the dry specimens was dipped in a solution of a chlorinated cleaner until the final weight of the specimen was about 2.26 times greater than the original weight. After weighing, the wet specimen was mounted on a support, to which a weight of 3.5 Ib was applied. The specimen was pushed and pulled forwardly and backwardly within one step of the user in a horizontal direction along the floor surface to wipe the floor. No vertical load was applied to the specimen. The frequency of push and pull movements was counted until the stains disappeared.

[115] [116] Table 3 [Table 3] [Table ]

[117] [118] 4. Absorbency Test [119] First, dry specimens of the cleaning mats were weighed. Each of the specimens was dipped in a water container. When the specimen was stretched flat, it was taken out of the container. The specimen was kept flat above the water container until no water was dropped from the specimen, and was then weighed. Further, the specimen was kept with an edge above the water container until no water was dropped from the specimen, and was then weighed.

[120] [121] Table 4 [Table 4] [Table ]

[122] [123] The results in Tables 1-4 reveal that the microfiber-containing knitted cloth of the present invention (Examples 1 and 2) showed better cleaning performance characteristics than the conventional products (Comparative Examples 1-5). Therefore, the microfiber-containing knitted cloth of the present invention can be applied anywhere the excellent cleaning characteristics are required and available.

[124] Although the present invention has been described herein with reference to the foregoing examples and the accompanying drawings, the scope of the present invention is defined by the claims that follow. Accordingly, those skilled in the art will appreciate that various substitutions, modifications and changes are possible, without departing from the spirit of the present invention as disclosed in the accompanying claims.

[125]

Claims

[I] A knitted fabric containing microfibers, comprising ground yarns for shape stability and pile yarns forming unit regions wherein each of the unit regions includes 64 to 84% by weight of first regions containing microfibers to offer cleaning performance, wiping performance and absorbency, 10 to 30% by weight of second regions allowing a pad to be easily pushed and 6 to 16% by weight of a third region serving to sweep dust or dirt, and the unit regions are formed in a repeating manner.

[2] The knitted fabric of claim 1, wherein each of the unit regions has a configuration in which the first region, the second region, the first region, the second region and the third region are arranged in this order.

[3] The knitted fabric of claim 2, wherein the first region, the second region, the first region, the second region and the third region are present in a weight ratio of 32-42 : 5-15 : 32-42 : 5-15 : 6-16 in each of the unit regions.

[4] The knitted fabric of claim 1, wherein each of the unit regions is formed by weaving such that the pile lengths of the first, second and third regions decrease in the order: the second regions > the third region > the first regions.

[5] The knitted fabric of claim 1, wherein the first regions are composed of twisted yarns that contain draw textured yarns containing polyester filament yarns having a total fineness of 100 to 400 D.

[6] The knitted fabric of claim 1, wherein the second regions are composed of twisted yarns that contain polyester textured yarns having a total fineness of 100 to 200 D.

[7] The knitted fabric of claim 1, wherein the third region is composed of poly olefin draw textured yarns having a total fineness of 300 to 600 D.

[8] A knitted fabric containing microfibers, comprising ground yarns for shape stability and pile yarns forming unit regions wherein each of the unit regions includes 62 to 75% by weight of region A containing split yarns as microfibers to offer cleaning performance, wiping performance and absorbency and 25 to 38% by weight of region B to allow a pad to be easily pushed, and the unit regions are formed in a repeating manner.

[9] The knitted fabric of claim 8, wherein the microfibers are nylon/polyester (NP) split yarns.

[10] The knitted fabric of claim 8, wherein each of the unit regions is formed by weaving such that the pile length of the region A is greater than that of the region B.

[I I] The knitted fabric of claim 8, wherein the region A is composed of twisted yarns having a total fineness of 100 to 400 D. [12] The knitted fabric of claim 8, wherein the region B is composed of twisted yarns that contain polyester textured yarns having a total fineness of 100 to 200 D. [13] The knitted fabric of claim 1 or 8, wherein the unit regions are formed in a linear or wave-like pattern. [14] The knitted fabric of claim 13, wherein the wave-like pattern is a waveform, pulse- wave or zigzag pattern. [15] The knitted fabric of claim 1 or 8, wherein the ground yarns contain high stretch yarns having a total fineness of 100 to 200 D. [16] The knitted fabric of claim 15, wherein the high stretch yarns are selected from the group consisting of spandex, elastic yarns, latent self crimping yarns, mechanical crimping yarns, and combinations thereof. [17] The knitted fabric of claim 1 or 8, wherein the ground yarns are selected from the group consisting of polyurethane fibers, polyester fibers, acrylic fibers, and combinations thereof. [18] The knitted fabric of claim 1 or 8, wherein the knitted fabric is pushed and pulled at a pressure of 0.50 to 0.55 Ib and a tension of 0.60 to 0.80 Ib in a dry state

(moisture content < 5%) on a floor inclined at an angle of 30° relative to the knitted fabric. [19] The knitted fabric of claim 1 or 8, wherein the knitted fabric is pushed and pulled at a pressure of 2.30 to 2.50 Ib and a tension of 4.90 to 5.20 Ib in a dry or wet state on a floor inclined at an angle of 60° relative to the knitted fabric when a weight of 3.5 Ib is added thereto. [20] The knitted fabric of claim 1 or 8, wherein the knitted fabric has a dust removal efficiency of 99% or above in a wet state. [21] A cleaning pad comprising: a pad layer formed of the knitted fabric of claim 1 or 8; an absorbing layer attached to the back surface of the pad layer and formed of a foamed polymer, a sponge or a non-woven fabric web to absorb moisture or oil; and a removable layer attached to the back surface of the absorbing layer and including Velcro, a button, a zipper or strings to offer the convenience of washing.