JP2019041861A - Wiping cloth - Google Patents

Abstract

To provide a wiping cloth having excellent wiping property and water retention to both aqueous dirt and oily dirt, and capable of suppressing flaw or fluff fall on a wiping object surface.SOLUTION: A wiping cloth comprises a woven/knitted fabric containing polyester ultra fine fibers having micropores on the surface of a single fiber. A single fiber fineness of the polyester ultra fine fibers is 0.1 dtex-1.5 dtex, and a surface side layer and/or a back side layer of the woven/knitted fabric contain the polyester ultra fine fibers at the ratio of 50 mass% or more.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a wiping cloth which has excellent wiping properties and water retentivity against both aqueous stains and oily stains, suppresses the occurrence of scratches on the surface to be wiped, and suppresses fuzzing. .

  Conventionally, wiping cloths have been developed in a wide range of fields from household uses such as household cleaning tools and eyeglasses to industrial uses such as automobile cleaning and wiping tools.

  Cellulosic fibers such as cotton are known as fibers used for wiping cloths. Since cellulosic fibers are hydrophilic fibers, they are suitably used as cleaning cloths and wiping cloths such as eyeglasses and lenses. For example, Patent Document 1 proposes a technology for providing a fabric excellent in the wiping performance of water-based dirt and oil-based dirt by cross-weaving cotton which is a hydrophilic fiber and polyester which is a hydrophobic fiber.

JP 2002-263044 A JP 2007-029264 A

  However, in patent document 1, since single fiber fineness of cotton is large, there exists a problem that the removal performance of fine dust is scarce. Furthermore, since cotton is in the form of a spun yarn in which staple fibers are spun, fluff may fall on the surface of the object to be wiped and remain on the wiping surface, which may rather contaminate the wiping surface. Furthermore, when cotton is used, various bacteria are easily generated, which may be unpreferable in terms of hygiene.

  Therefore, a woven or non-woven fabric is proposed in which the surface area is expanded by using polyester fibers as fibers constituting the wiping cloth, and the wiping performance is improved and the fine dust wiping performance is further improved. For example, Patent Document 2 proposes a technique for providing a fabric which is made of polyester microfibers and is excellent in wiping performance. However, although the wiping performance to oil stains is excellent in Patent Document 2, there is a problem that the wiping performance to water stains is not sufficiently satisfied because the polyester fiber is hydrophobic and has poor water retention. In addition, although unevenness is provided on the cloth surface and dirt removal performance and water retention are improved by transferring dirt to the recess, problems with productivity and quality may occur due to the restriction of the weave and knitting structure etc. Therefore, it is desirable to improve the wiping properties and the water retention without depending on the composition of the fabric.

  Furthermore, as in Patent Document 2, in the case of a wiping cloth using a non-woven fabric, the fibers extend irregularly and irregularly, which limits the wiping efficiency. Specifically, the fine dust and the like attached to the wiping surface is mainly transmitted by the contact of the side surface of the component fiber with the wiping force and peeled off from the surface to be wiped off, but the component fiber is irregular If it is oriented in the proper direction, peeling of fine dust and the like may not be effectively performed depending on the direction, and the wiping operation may be required many times until a sufficient wiping effect is obtained. Or, there is a problem such as changing the direction of the non-woven fabric and re-wiping. In addition, with some nonwoven fabrics, fibers were shredded and fuzzed off, and during wiping, the fibers could fall off from the wiping cloth and conversely contaminate the wiping surface.

  As described above, in the prior art, a wiping cloth having sufficient wiping performance against both aqueous stains and oily stains without particularly devising the constitution of the fabric, and having excellent water retention and suppressed fuzzing The present condition is that you can not get

  The present inventors examined the relationship between the micropores formed on the surface of monofilaments of polyester microfibers and the water retentivity and the wiping property in the wiping cloth. As a result, it has been found that polyester microfibers having micropores on the surface of a single fiber can obtain water retention and wiping performance suitable for wiping cloth applications by the micropores without particularly devising the fabric configuration. , Completed the present invention.

That is, this invention makes the following (1)-(7) a summary.
(1) A wiping cloth comprising a woven or knitted fabric containing polyester microfibers having micropores on the surface of a monofilament,
The single fiber fineness of the polyester ultrafine fiber is 0.1 dtex to 1.5 dtex,
A wiping cloth comprising the polyester microfibers in a proportion of 50% by mass or more in the front side layer and / or the back side layer of the woven or knitted fabric.
(2) The number of micropores is 5 or more (12.5 × 10 ⁵ / mm ² or more) in a square area of 2 μm in length × 2 μm in width on the surface of the single fiber, and the length of the major axis is short The wiping cloth of (1), wherein the length of the long axis is equal to or longer than the length of the short axis, and the length of the long axis is 0.05 μm or more and the length of the short axis is 0.6 μm or less.
(3) The dynamic friction resistance is 1.90 to 2.50 N and the static friction resistance is 1.90 to 2.50 N in any of the vertical direction and the horizontal direction of the wiping cloth. ) Wiping cloth.
(4) A wiping cloth according to any one of (1) to (3), which is napped or haired.
(5) The wiping cloth in any one of (1)-(4) which is water absorption processed.
(6) The wiping cloth in any one of (1)-(5) whose glossiness retention after wiping off 3 times is 90% or more.
(7) The wiping cloth in any one of (1)-(6) whose water retention is 180% or more.

  Since the wiping cloth of the present invention has fine pores on the surface of the fiber, it has excellent wiping performance against both aqueous stains and oily stains, and it is further excellent in water retention, and is a target of wiping. Scratches on the surface are suppressed. Therefore, it can be used for wiping cloths for household materials such as glasses, furniture, or metal products, and also for cloths for industrial materials such as ICs or semiconductors. Furthermore, since the polyester microfiber contained in the wiping cloth of the present invention is derived from the production method thereof and a reduction in strength is suppressed, fuzzing is suppressed and structural fibers are also suppressed from falling off during wiping Can be suitably adopted for use in a clean room where dust generation is a problem.

It is a cross-sectional schematic diagram which shows one embodiment of the modified cross section of the single yarn which comprises a split-type polyester composite fiber used when manufacturing the wiping cloth of this invention. It is the photograph (magnification; 20000 times) which image | photographed the monofilament surface of the polyester microfiber contained in the wiping cloth obtained in Example 1. FIG. It is the photograph (magnification; 20000 times) which image | photographed the monofilament surface of the polyester microfiber contained in the wiping cloth obtained by the comparative example 1. FIG.

Hereinafter, the present invention will be described in detail.
The wiping cloth of the present invention comprises a woven or knitted fabric containing polyester microfibers having micropores on the surface of monofilaments. In the front side layer and / or the back side layer of the woven or knitted fabric, polyester microfibers are present at 50% or more. The wiping cloth of the present invention preferably has a dynamic friction resistance of 1.90 to 2.50 N and a static friction resistance of 1.90 to 2.50 N in any of the vertical direction and the horizontal direction.

In the present invention, fine pores in polyester microfibers will be described below.
In order to enhance the wiping performance and the water retention performance, it is necessary for the fine fiber surface of the polyester microfiber to have fine dust, oil droplets, and micropores that can correspond to the presence of water on the surface to be wiped. That is, the present invention is the first to find and achieve the relationship between the micropores present on the surface of the monofilaments of polyester microfibers, which are the constituent fibers of the wiping cloth, and the wiping properties and water retention to aqueous stains and oily stains.

  The size of the micropores is such that the major axis is equal to or longer than the minor axis, and from the viewpoint of wiping properties and water retention, preferably, the major axis has a length of 0.05 μm or more and the minor axis has a diameter of 0. 6 μm or less. Among them, the major axis is more preferably 0.05 to 1.5 μm and the minor axis is 0.01 to 0.5 μm. More preferably, the major axis is 0.1 to 1.2 μm and the minor axis is 0.02 to 0.4 μm.

  The aspect ratio (major axis / minor axis) of the micropores is preferably 15/1 to 2/1. If the aspect ratio is in this range, the major axis is sufficiently long with respect to the minor axis, and the change in the size of the fiber cross-sectional area is small, and thus the single fiber strength is difficult to partially weaken. The water retentivity is excellent without lowering the

Furthermore, in order to enhance the wiping performance and water retention performance, the micropores are present in a number of 5 or more (12.5 × 10 ⁵ / mm ² or more) in a square area of 2 μm in length × 2 μm in width on the single fiber surface. It is preferable to exist, and it is more preferable to exist by number of ten or more (25.0 * 10 < ⁵ > piece / mm < ² > or more). With such a number, fine pores are present at a high density on the surface of the single fiber, so that the wiping performance and the water retention are further excellent. The upper limit of the number of micropores in the 2 μm × 2 μm region is not particularly limited, but is about 50 (about 125.0 × 10 ⁵ / mm ² ), and the number of micropores is 45 or less (112.5) It is more preferably × 10 ⁵ pieces / mm ² or less, and still more preferably 40 pieces or less (100.0 × 10 ⁵ pieces / mm ² or less).

  The surface of the woven or knitted fabric corresponds to the wiping surface when it is used as a wiping cloth. By reducing the single fiber fineness of the polyester microfibers, it is possible to quickly suck up water or liquid on the surface of the object using capillary action. Then, by reducing the single fiber fineness of the polyester ultrafine fibers, fine dirt adhering to the surface of the object can be efficiently scraped off. However, if it is too thin, the rigidity of the fiber is lost, and it adheres easily to the object with a little finger pressure, making it difficult to move the wiping cloth smoothly. Specifically, when the single fiber fineness is less than 0.1 dtex, the ability to remove dirt is improved, but the contact area with the object is also increased, so movement of the cloth is hindered when water or liquid intervenes. Not only is it easy to scratch the surface to be wiped, it also reduces the water retention. In addition, the fineness of the single fiber is too thin, the yarn strength is reduced, and fuzzing occurs. On the other hand, if it exceeds 1.5 dtex, the ability to remove dirt decreases, and furthermore, capillary action becomes difficult to work, so water and the like can not be absorbed quickly. The number of filaments of the polyester ultrafine fibers is not particularly limited, but is preferably, for example, about 100 to 1,500.

  In the present invention, the surface of an object can be wiped while quickly removing adhering water or liquid matter. In order to absorb water and the like, it is generally preferred to use a hydrophilic fiber. However, if the surface is constructed using hydrophilic fiber yarn, although the water absorbability is secured, water etc. will be retained in the yarn itself, and a mark of a drop will remain. In addition, it is difficult to squeeze water after wiping off using hydrophilic fiber yarn. Therefore, in the present invention, polyester microfibers which are hydrophobic fibers are used. If it is a fiber using polyester, it is easy to squeeze water and the drying speed is also fast. However, on the other hand, polyester fiber itself is a hydrophobic yarn, so it can not absorb water etc. quickly simply by using it. Therefore, as described above, the micropores are made to exist on the monofilament surface of the polyester microfiber, and at the same time, the monofilament fineness is optimized. Thereby, water etc. can be absorbed quickly, and a wiping cloth excellent in water retention and wiping properties can be obtained. That is, even in the case of using hydrophobic fibers, the present invention is to obtain a wiping cloth which is excellent in both wiping performance and water retention by optimizing the fine pores present on the surface of the fibers and the fineness of single fibers. And was achieved.

  In the wiping cloth of the present invention, the dynamic friction resistance is preferably 1.90 to 2.50 N and the static friction resistance is preferably 1.90 to 2.50 N in both the vertical direction and the horizontal direction. Is more preferably 1.96 to 2.45 N and the static friction resistance is 1.96 to 2.45 N, the dynamic friction resistance is 1.96 to 2.35 N, and the static friction resistance is 1.96 to 2 Particularly preferred is .35N. In the present invention, the dynamic friction resistance and the static friction resistance can be made into the above-mentioned ranges by optimizing the micropores on the surface of the single fiber and the fineness of the single fiber. When the dynamic friction resistance and the static friction resistance are 2.50 N or less, scratches on the surface to be wiped can be further suppressed. When the dynamic friction resistance and the static friction resistance are 1.90 N or more, the wiping cloth does not move too smoothly, and the wiping performance and the water retention can be further enhanced. Usually, in the wiping cloth, when forming pores or the like (for example, pores larger than the micropores in the present invention) in the constituent fibers, making irregularities or narrowing the single fiber fineness of the constituent fibers, the target at the time of wiping In the wiping cloth of the present invention, micropores are present on the surface of the single fiber and the fineness of the single fiber is optimized in the wiping cloth of the present invention. Even if the properties and wiping properties are improved, the dynamic friction resistance and the static friction resistance can be maintained in a small range, and the generation of scratches can be suppressed. Methods of measuring dynamic friction resistance and static friction resistance are described in detail in the examples.

  In the front side layer and / or the back side layer of the woven or knitted fabric constituting the wiping cloth of the present invention, other yarns may be used in combination as long as the effects of the present invention are not impaired in addition to the above polyester microfibers. The composition, form, and the like of the other yarns are not particularly limited, but in order to reduce dust generation, it is preferable to use a filament type.

  In the front side layer and / or the back side layer of the woven or knitted fabric constituting the wiping cloth of the present invention, the above-mentioned polyester microfibers are present in a proportion of 50% by mass or more in order to exert the effects of the present invention It is preferable that it is mass% or more, It is more preferable that it is 90 mass% or more, It is more preferable that it is 100 mass%.

  The wiping cloth of the present invention may be a multi-layered fabric in which a woven or knitted fabric including polyester microfibers as a front side layer and a back side layer is disposed, and another fiber layer may be interposed between the front side layer and the back side layer. You may have.

  In the wiping cloth of the present invention, for the purpose of improving absorption and water retention performance, processing such as water absorption processing or raising processing or hair cutting processing can be performed. Such processing can be performed under the condition that the micropores on the surface of the ultrafine polyester fiber which is the constituent fiber are not deformed.

  The wiping cloth of the present invention exhibits excellent wiping performance and water retention due to the fine pores and the single fiber fineness on the surface of the polyester ultrafine fibers which are constituent fibers, without specially devising the constitution of the woven or knitted fabric However, in order to make such effects more manifest, the surface may be provided with height differences to form asperities. The uneven portion further maintains the wiping property. It is preferable that this uneven part does not look like a pile as a convex part, but forms a form with a difference in elevation on the surface by devising a woven structure or a knitted structure. The lower portion becomes a recess, and the space between the recess and the recess is relatively raised and becomes a protrusion. Moreover, the uneven part changes the thickness of constituent fibers by mixing yarns thicker than the above-mentioned polyester ultrafine fibers, in addition to devising a woven structure and a knitted structure, and alternates the constituent fibers having different thicknesses or The uneven portion may be formed by arranging at a constant ratio. Alternatively, the uneven portion may be formed by using a polyester high shrinkage yarn.

  With such an uneven portion, the fibers disposed on the convex portion scrape dirt from the surface of the object, and then the dirt is transferred to the concave portion and retained, so that the wiping property is further sustained. Furthermore, since only the convex portion easily contacts the object, the contact area can be reduced, and the wiping cloth can be made to move more smoothly. Uneven portions can be formed using yarns other than polyester ultrafine fibers, but as described above, polyester ultrafine fibers are present in 50% or more of the surface of the woven or knitted fabric from the viewpoint of wiping properties and water retention. is necessary.

  The height difference of the uneven portion is preferably 0.5 mm or less, more preferably 0.2 mm to 0.4 mm. When the height difference is 0.5 mm or less, restrictions on the woven structure, the knitted structure, and the like are reduced, and the productivity and the quality become better. Furthermore, since it is hard to become a form which a convex part protrudes excessively and it becomes easy to spread finger pressure entirely, wiping off property becomes still better. In addition, the depression of the recess does not become too large, and the entire knitted fabric has few voids, and the total contact area with the object does not become too small, and the water absorbability becomes better. On the other hand, if the height difference is too small, the wiping resistance may increase and the wiping performance may decrease, but if the object to be wiped is very fine, it may be easier to wipe if the height difference is not attached.

  In the wiping cloth of the present invention, the gloss retention is employed as an index of the wiping property. Specifically, the gloss retention after three wipings is preferably 90% or more, more preferably 93% or more, and still more preferably 94%. When the gloss retention is in this range, it has sufficient wiping properties against oily stains. The method of measuring the gloss retention will be described in detail in the examples.

  The wiping cloth of the present invention is excellent in water retention, and the water retention ratio as an index of water retention is preferably 180% or more, and more preferably 185% or more. When the water retentivity is in this range, it has sufficient wiping properties against aqueous stains. The method of measuring the water retention rate will be described in detail in the examples.

  The thickness of the wiping cloth of the present invention is preferably 0.7 to 2 mm. Even if the thickness is less than 0.7 mm, the water retention rate does not immediately decrease, but if it is 0.7 mm or more, it tends to easily reach the water retention limit during water retention, and the amount of water adhering to the object surface Is preferable because it is possible to cope with even when the On the other hand, it is preferable that the thickness be 2.0 mm or less, since it is difficult to apply wiping pressure if the thickness is too large.

  In the present invention, as described above, due to the optimization of the single fiber fineness of the polyester ultrafine fibers that are constituent fibers and the micropores on the fiber surface, the synergetic effect of these does not particularly improve the configuration of the woven or knitted fabric, It is possible to provide a wiping cloth which has good wiping properties, can be used repeatedly, can suppress the occurrence of scratches, and can finish the object aesthetically and easily.

  In the woven or knitted fabric constituting the wiping cloth of the present invention, by appropriately adjusting the post-processing conditions and the like of the woven or knitted fabric, it becomes easy to adjust the fabric weight, thickness and the like, and a wiping cloth having even more excellent water absorbency and water retention is obtained. be able to.

The method for producing the wiping cloth of the present invention will be described below.
First, a splittable polyester composite fiber is prepared. In the splittable polyester composite fiber, a polyester resin composition (poorly soluble polyester resin composition) which is hardly soluble in alkali is divided into a plurality of parts by a polyester resin (soluble polyester resin) which is easily soluble in alkali It will be done. As shown in FIG. 1, the splittable polyester composite fiber of the present invention has a configuration in which a hardly soluble polyester resin composition B is divided into a plurality of parts by a highly soluble polyester resin A in a cross section.

  The poorly soluble polyester resin composition comprises a poorly soluble polyester resin and product particles. The produced particles are derived from a phosphorus compound and an alkaline earth metal compound, or are derived from a phosphorus compound and an alkali metal compound and an alkaline earth metal compound. The average particle size of the produced particles is preferably, for example, 0.05 to 0.5 μm.

  When the average particle diameter is in the above range, it is preferable in order to be able to form fine pores having a suitable size as described later at a high density (number of particles in a specific range) after the alkali reduction treatment. The average particle diameter of the produced particles can be controlled within the above range, for example, by preferably adding the combination of the phosphorus compound and the metal compound or the addition amount of the phosphorus compound and the metal compound. The preferable combination of the phosphorus compound and the metal compound in the present invention, and the addition amount of the phosphorus compound and the metal compound will be described later. Note that, instead of adding known inert fine particles such as silica fine particles, by using generated particles, coarsening of the fine particles due to aggregation can be further suppressed, and fine pores having a preferred size can be further formed with high density. It becomes easy to do. In addition, using the generated particles, the major axis of the micropores formed on the surface can be made sufficiently long with respect to the minor axis as compared with the case where inert fine particles are added, and the above aspect ratio It can be in a suitable range. Although the reason is not clear, the present inventors speculate that this is because the produced particles are softer than inert fine particles, and are easy to stretch in a spinning process, a drawing process, or the like.

  In order to obtain a poorly soluble polyester resin composition, the dicarboxylic acid component and the diol component are subjected to an esterification reaction to form a polyester oligomer, and a phosphorus compound and an alkaline earth metal compound are added, or a phosphorus compound And an alkali metal compound and an alkaline earth metal compound are added, followed by a polycondensation reaction. Then, in the cross section of the fiber, the poorly soluble polyester resin composition is disposed so as to divide the easily soluble polyester resin, and composite spinning is performed to obtain a splittable polyester composite fiber. The split-type polyester composite fiber may be subjected to a draw texturing process. Thereby, the major axis of the micropores formed on the surface can be made sufficiently long with respect to the minor axis, and the above-mentioned aspect ratio can be made into a suitable range.

  As a phosphorus compound, phosphoric acid, phosphonic acids, or phosphinic acids are mentioned, for example. Among these, aliphatic phosphoric acids are preferable, and phosphoric acid esters are particularly preferable because the average particle diameter of the produced particles is not too large and the stability of the spinning process becomes good. Among the phosphate esters, triethyl phosphate (triethyl phosphate, TEP) is particularly preferable from the viewpoint of being excellent in deep dyeability.

  The alkali metal compound is, in particular, an alkali metal salt of a carboxylic acid, and specific examples thereof include lithium acetate, sodium acetate, potassium acetate, lithium benzoate, sodium benzoate or potassium benzoate. Among these, lithium acetate is preferable because the average particle diameter of the produced particles is in the optimum range and byproducts can be suppressed during the polymerization reaction of the polyester.

  The alkaline earth metal compounds are, in particular, alkaline earth metal salts of carboxylic acids, and as specific examples thereof, magnesium acetate, calcium acetate, magnesium oxalate, calcium propionate, calcium stearate, magnesium stearate, calcium benzoate Or manganese acetate. In particular, when a magnesium salt of a carboxylic acid is used, the particle diameter of the produced particles formed in the polyester resin is not excessive, and the stability of the spinning process of the polyester fiber is favorable, which is preferable. Among them, magnesium acetate is particularly preferable because of its excellent handleability.

  The preferable combination of the phosphorus compound and the metal compound makes it easy to control the average particle size of the produced particles in a preferable range, and from the viewpoint of obtaining a wiping cloth having further excellent wiping properties and water retention, a phosphate and a metal salt of acetic acid. A combination is preferred, more preferably a combination of triethyl phosphate (triethyl phosphate) and magnesium acetate, and furthermore, in addition to these, it is most preferable to use lithium acetate in combination. When lithium acetate is used alone as the metal compound, the produced particles may be too coarse. That is, in the present invention, triethyl phosphate (triethyl phosphate) as a phosphorus compound and magnesium acetate as a metal compound are easy to control the average particle diameter of the produced particles within the above range and to improve the wiping properties and water retention more. And in combination with lithium acetate.

The amount of the metal compound added is preferably 10 × 10 ^{−4 to} 100 × 10 ⁻⁴ mol, more preferably 25 × 10 ⁻⁴ to 80 × 10 ⁻⁴ mol, per 1 mol of the acid component constituting the polyester. the mole, more preferably 30 × ^{10 -4} ~80 × ¹⁰ -4 mol, particularly preferably from 45 × ^{10 -4} ~80 × ¹⁰ -4 mol. If the content is 10 × 10 ⁻⁴ or more, generated particles of a size sufficient to improve the wiping properties and water retention are easily formed, and the above-mentioned number of micropores are more easily developed. Since generation | occurrence | production of coarse particles can be further suppressed as it is 100 * 10 <^-4> mol or less, clogging of the filter which filters the polyester resin composition which fuse | melted at the time of spinning can be suppressed, and the stability of a yarn production process is more favorable. You can keep

The amount of the phosphorus compound added is preferably 10 × 10 ^{−4 to} 100 × 10 ⁻⁴ mol, more preferably 20 × 10 ^{−4 to} 90 × 10 ⁻⁴ mol, per 1 mol of the acid component constituting the polyester. The molar amount is more preferably 30 × 10 ^{−4 to} 90 × 10 ⁻⁴ mol, and particularly preferably 45 × 10 ^{−4 to} 90 × 10 ⁻⁴ mol. If the content is 10 × 10 ⁻⁴ mol or more, it will be easy to form product particles of a size sufficient to make the wiping properties and water retention better, and it will be easy to develop the aforementioned number of micropores. Since generation | occurrence | production of coarse production particle | grains can be further suppressed as it is 100 * 10 <^-4> mol or less, clogging of the filter which filters the polyester resin composition which fuse | melted at the time of spinning can be suppressed, You can keep better. The molar ratio between the metal compound and the phosphorus compound is preferably (metal compound) / (phosphorus compound) = 0.5 to 1.5 in order to obtain excellent spinning stability, wiping performance and water retention.

  Then, after knitting or weaving a woven or knitted fabric containing splittable polyester composite fibers, the basic compound is brought into contact and alkali reduction treatment is performed to dissolve easily soluble polyester resin with respect to alkali, and it is difficult with respect to alkali The portion made of the soluble polyester resin composition is divided (split) to form polyester ultrafine fibers, and the produced particles present on the surface of monofilaments formed from the poorly soluble polyester resin composition are detached to form micropores. Do. Thereby, the wiping cloth of the present invention is obtained. In addition, it is preferable that an alkali weight loss rate is selected in the range which reduces a soluble polyester resin completely (elution).

  By alkali reduction treatment, fine pores having an appropriate size can be formed at high density on the surface of single fiber, and excellent wiping performance can be obtained due to the fine pores and single fiber fineness narrowed by splitting. And water retention develops. The contact with the basic compound can be carried out, for example, by treatment with an aqueous solution of the basic compound.

  In the present invention, since degradation of the yarn due to the alkali reduction treatment can be minimized because separation of the fibers (splitting) and falling off of the generated particles can be minimized, the yarn quality does not become brittle and the strength is high. While being able to suppress a fall and being able to control fuzzing by thread breakage etc., it is possible to achieve excellent wiping properties due to the fineness. In addition, compared with the case where ultrafine fibers are obtained by direct spinning and the resulting particles are dropped off by alkali reduction treatment, when the fiber is split, the fiber shape has, for example, a wedge-like corner and In addition to being excellent in wiping properties, it is possible to further suppress the reduction in dynamic friction resistance and static friction resistance.

  The method of using the wiping cloth of the present invention will be described below. The surface of the wiping cloth of the present invention (the surface containing the above-mentioned polyester microfibers) may be directed to the object, and finger pressure may be applied to the other surface and used as it is. Alternatively, the other surfaces may be overlapped and the edge may be sewn. By doing so, both surfaces become wiping surfaces after sewing, which makes it easier to use and the gap in the overlapping portion Water can be stored, and it is possible to expect further increase in water holding capacity. For this reason, much water etc. can be wiped off by one-time wiping off.

  The wiping cloth of the present invention is suitable, for example, for wiping up a car after washing a car, wiping off a brass instrument, wiping off oil stains in a kitchen or the like, or wiping a window. In particular, the wiping cloth of the present invention is suitable mainly for wiping up an automobile in which an emulsion cleaner is used, in order to exert excellent wiping properties against both aqueous stains and oily stains. When the wiping cloth of the present invention is used, traces of drops or scratches are unlikely to remain after wiping, and fluffing and the like are suppressed, so that the object can be beautifully finished.

  Hereinafter, the present invention will be specifically described according to examples. The invention is not limited to this example.

The measurement method or evaluation method in the embodiment of the present invention is as follows.
(1) Number of Micropores Ten single fibers of polyester microfiber were randomly collected from the wiping cloths obtained in Examples or Comparative Examples. The surface of this single fiber was photographed at 20000 × magnification using a scanning electron microscope (SEM). In the photographed photograph, a square inspection area corresponding to 2 μm in length × 2 μm in width was randomly set, the number of micropores present in this area was counted, and the average value was adopted.

(2) Size of Micropores In the photograph taken in the above (1), 30 micropores present on the fiber surface were randomly selected. The length in the longitudinal direction of the fiber was taken as the major axis, the length in the direction orthogonal to the longitudinal direction was taken as the minor axis, and the average value of each was determined.

(3) Wiping performance (gloss retention rate)
At the center of the slide glass, beef tallow was thinly coated in a circular shape of 1.5 cm in diameter. And this slide glass was installed in Gakushin II type | mold testing machine (made by Rainforest Mfg. Co., Ltd.), and it wiped off 3 times by 500 g of loads using the wiping cloth obtained by the Example or the comparative example. Based on the values measured with a variable-angle gloss meter (Suga Test Instruments Co., Ltd., product number “UGV-5D”) (incident angle 45 °, light receiving angle 45 °) for quantifying the degree of gloss on the surface of an object, beef tallow The percentage of the measured value after wiping 3 times was taken as the gloss retention, assuming that the measured value when 100% was not applied was 100%.

Moreover, the slide glass after wiping 3 times as mentioned above was observed visually, and sensory evaluation of wiping off property was performed on the following reference | standard.
○: beef tallow can not be checked visually.
:: Some beef tallow remains.
X: Many tallow remains.

Moreover, the slide glass after wiping off 3 times as mentioned above was observed visually, and sensory evaluation of the flaw suppression property was performed on the following reference | standard.
○: Wounds can not be visually confirmed on the wiped surface.
X: The scratch can be visually confirmed on the wiping surface.

(4) Water retention (water retention rate)
The wiping cloths obtained in Examples and Comparative Examples were cut into 25 cm squares in the vertical direction and in the horizontal direction to obtain samples. The sample mass (W0) before being subjected to the test was measured, and then the sample was immersed in distilled water for 10 minutes. After immersion, one end of each of the four corners of the sample was lifted and allowed to stand still for 10 minutes, and then the mass (W1) was measured. And water retention rate was computed by the following formula.
Water retention rate (%) = [(W1-W0) / W0] × 100

Moreover, the sample after measuring the said mass (WI) was slightly pinched with the thumb and forefinger, and sensory evaluation was performed on the following reference | standard.
○: A lot of water was dripping.
Fair: Drip of water was normal.
X: There was little dripping of water.

(5) Dynamic Friction Resistance, Static Friction Resistance Using a load cell of a constant velocity elongation type single thread tensile tester (manufactured by Shimadzu Corporation), the dynamic friction resistance and the static friction resistance were measured when pulled in the horizontal direction. The contact surface was a stainless steel plate, the test speed was 100 mm / min, the size of the measurement sample was 63 mm × 63 mm, and the test load was 0.5 kg (load area was 63 mm × 63 mm).

(6) Fuzzing property The wiping was performed 1000 times by the method similar to the evaluation method of the wiping property of said (3). Thereafter, the slide glass was visually observed and observed to determine whether the constituent fibers were broken and fell off or not.

(7) Thickness of wiping cloth It measured based on JIS L1096 8.4.

Example 1
First, a polyester resin composition which is poorly soluble in alkali was prepared as follows. A slurry of terephthalic acid (TPA) and ethylene glycol (EG) (having a molar ratio of TPA: EG = 1.6) is continuously supplied to an esterification reactor in which a polyester low polymer is present, and the temperature is 250 ° C. and the pressure is The reaction was carried out under the condition of 50 hPa to continuously obtain a polyester low polymer having an esterification conversion rate of 95%. The polyester low polymer was charged into a polycondensation reaction vessel, and the inside of the vessel was replaced with nitrogen. Then, 2.0 × 10 ^-4 moles of antimony trioxide as a polycondensation catalyst per mole of acid component constituting the polyester, and triethyl phosphate (TEP) as a phosphorus compound per mole of acid component constituting the polyester ^{60.times.10@-4} mol of magnesium acetate was added to ^{50.times.10@-4} mol with respect to 1 mol of the acid component constituting the polyester. The pressure was gradually reduced to 1.2 hPa or less after 1 hour. After carrying out a polycondensation reaction for 4 hours while stirring under these conditions, the resultant was dispensed and pelletized by a conventional method to obtain a polyester resin composition which is hardly soluble in alkali having an intrinsic viscosity of 0.69 dL / g.

  A polyester resin composition which is hardly soluble in alkali, and a polyester resin which is easily soluble in alkali (polyethylene glycol 12 having 2.0% by mass of sodium sulfonate, that is, 2.0% by mole, and an average molecular weight of 6000) .0% by mass, that is, a copolymerized polyester obtained by copolymerizing 12.0% by mol, into a conventional melt-spinning machine, and the mass ratio (a hardly soluble polyester resin composition: a readily soluble polyester resin) is 80:20. As a result, the easily soluble polyester resin was spun out from a die in which 48 spinning holes capable of spinning a cross-sectional shaped fiber in which the poorly soluble polyester resin composition is divided into eight are drilled. The spun yarn was cooled by an air stream and passed through an oiling device (oil agent feeding device) to apply an oil agent. The yarn was withdrawn at a spinning speed of 3500 m / min (105 dtex 48 f). The obtained yarn is drawn 1.25 times through a heat roller at 85 ° C. with a common drawing machine, and further heat treated with a heat plate at 170 ° C., wound up, and drawn as shown in FIG. A polyester fiber (splittable polyester composite fiber) having a cross-sectional shape as shown in (d) was obtained (84 dtex 48 f).

  This split-type polyester composite fiber is used for the surface layer and the back layer, and a polyester high-shrinkage yarn (33 dtex 12 f) having a boiling water shrinkage of 22% is used for the middle layer, and WIL with a Takiguchi machine (cattle diameter 37 inches, needle density 26 G) The organization's circular knit was knitted. After knitting, the raw machine was scoured at 80 ° C. for 20 minutes with a jet flow dyeing machine. After that, using a bath having an alkali concentration of 20 g / L, the fiber was split by performing alkali reduction treatment under the conditions of 100 ° C. and 30 minutes (weight loss rate: 20 mass%). Subsequently, using 3.0% omf of SR 1801 conc (manufactured by Takamatsu Yushi Co., Ltd., hydrophilic polyester resin), relaxation treatment and water absorption processing were simultaneously performed under conditions of 130 ° C. and 30 minutes with a jet flow dyeing machine . Thereafter, final setting was performed at 170 ° C. for 1 minute to obtain a wiping cloth.

(Example 2)
After alkaline splitting, a wiping cloth was obtained in the same manner as in Example 1 except that the hair was raised according to a conventional method.

(Comparative example 1)
The procedure was carried out in the same manner as in Example 1 except that polyethylene terephthalate having an intrinsic viscosity of 0.65 dL / g (polyethylene terephthalate containing no particles produced) was used in place of the polyester resin composition which is hardly soluble in alkali. , I got a wiping cloth.

(Comparative example 2)
Example 1 was carried out in the same manner as Example 1 except that the cross-sectional shape was changed to a cross-sectional shape in which the polyester resin composition hardly soluble in alkali is divided into 20 as shown in (g) of FIG.

(Comparative example 3)
A wiping cloth was obtained in the same manner as in Comparative Example 2 except that polyethylene terephthalate having an intrinsic viscosity of 0.65 dL / g was used in place of the polyester resin composition having a low solubility in alkali.

(Comparative example 4)
A polyethylene terephthalate yarn (84 dtex 48 f, titanium oxide content 0.06 mass%) having a triangular cross-sectional shape is disposed as a napped portion at the front portion, and a polyethylene terephthalate yarn (56 dtex 24 f) having a circular cross-sectional shape of 56 dtex 24 f. 5% by mass) is placed in the middle part as the ground part, and a polyethylene terephthalate yarn (56 dtex 24f, 0.5% by mass of titanium oxide content) having a round cross sectional shape of 56 dtex 24 f is placed in the back part as the ground part. Knitting was carried out with (Kallmeyer Inc., gauge: 28 G). The warp knitting structure is a knitting structure of front 1-0 / 5-6, middle 1-0 / 2-3, and back 1-0 / 1-2, and the knitting density (machine upper course) at this time is 85 courses / In inches. Set this drying machine in a dry-heat box, and after shearing (punching), finish dyeing by a conventional method, and wipe it with 38 wales / inch, 65 courses / inch, fabric weight 300g / cm ² velor navy warp knitted fabric I got

(Comparative example 5)
A polyethylene terephthalate yarn (56 dtex 36 f, 0.5 mass% of titanium oxide content) having a triangular cross-sectional shape of Semidal 56 dtex 36 f is disposed as a raised portion at the front portion, and a polyethylene terephthalate yarn (56 dtex 24 f, containing titanium oxide) with a circular cross-sectional shape of 56 dtex 24 f. An amount of 0.5% by mass) is disposed in the middle portion as a ground portion, and a polyethylene terephthalate yarn (56 dtex 24f, 0.5 mass% in titanium oxide content) having a round cross-sectional shape is disposed in a back portion as a ground portion. The machine was knitted with a machine (Kaelmayer, gauge: 28 G). The warp knitting structure is a knitting structure of front 1-0 / 4-5, middle 1-0 / 1-2 and back 1-0 / 2-3, and the knitting density (machine upper course) at this time is 65 courses / In inches. Set this drying machine in a dry-heat box, and after shearing (shearing), finish dyeing in the usual way, and wipe it with 36 wales / inch, 61 courses / inch, fabric weight 202 g / cm ² velor navy warp knitted fabric I got

  The evaluation results of Examples 1 and 2 and Comparative Examples 1 to 5 are shown in Tables 1 and 2.

  The wiping cloths obtained in Examples 1 and 2 of the present invention were excellent in wiping properties and water retention, and at the same time, yarn breakage was also suppressed because the fiber strength did not decrease. Moreover, since dynamic friction resistance and static friction resistance were suppressed low, it was understood that generation | occurrence | production of the flaw of the wiping object surface can be suppressed. Furthermore, in Example 2 in which the raising process was performed, the wiping properties and the water retention were significantly improved as compared with Example 1.

  Comparative Example 1 and Comparative Example 3 using fibers without fine pores had low gloss retention. Thereby, it turned out that it is effective to wiping performance improvement, and that single fiber fineness has a good influence that constituent fibers have micropores on the surface. In addition, in Comparative Example 2, the wiping performance is excellent, but since the single fiber fineness of the polyester ultrafine fibers is too small, the water retention is poor and fuzzing is also observed. Further, in Comparative Examples 2 and 3, since the single fiber fineness of the polyester ultrafine fibers was too small, the dynamic friction resistance and the static friction resistance became too high, and a scratch was observed on the wiping target surface.

  In Comparative Examples 4 and 5, the water retention property was remarkably excellent because of the hair-cutting process, but although it is a modified cross-sectional fiber having a triangular cross-sectional shape, it has no micropores and is a single fiber Since the thick polyester fiber of fineness was used, it became a thing inferior to wiping off property notably.

  2 is a photograph (magnification: 20000 ×) of the surface of the polyester microfiber contained in the wiping cloth obtained in Example 1, and FIG. 3 is obtained in Comparative Example 1. It is the photograph (magnification; 20000x) which photographed the monofilament surface of the polyester microfiber contained in the wiping cloth. From FIGS. 2 and 3, it is clear that, on the monofilament surface of the polyester microfiber in Example 1, compared with Comparative Example 1, fine pores of an optimum size are present at a high density.

A: Alkali-soluble polyester resin B: Alkali-insoluble polyester resin composition

Claims (7)

A wiping cloth comprising a woven or knitted fabric containing polyester microfibers having micropores on the surface of a monofilament,
The single fiber fineness of the polyester ultrafine fiber is 0.1 dtex to 1.5 dtex,
A wiping cloth comprising the polyester microfibers in a proportion of 50% by mass or more in the front side layer and / or the back side layer of the woven or knitted fabric. The number of micropores is 5 or more (12.5 × 10 ⁵ / mm ² or more) in a square area of 2 μm in length × 2 μm in width on the surface of the single fiber, and the length of the major axis is short It is characterized in that it is equal to or longer than the length of the axis, the length of the long axis is 0.05 μm or more, and the length of the short axis is 0.6 μm or less. Wiping cross described in.   The dynamic friction resistance is 1.90 to 2.50 N and the static friction resistance is 1.90 to 2.50 N in any of the vertical direction and the horizontal direction of the wiping cloth. Or the wiping cloth described in 2.   The wiping cloth according to any one of claims 1 to 3, characterized in that it is napped or haired.   The wiping cloth according to any one of claims 1 to 4, which is subjected to water absorption processing.   The wiping cloth according to any one of claims 1 to 5, wherein the gloss retention after wiping 3 times is 90% or more. The wiping cloth according to any one of claims 1 to 6, wherein water retention is 180% or more.