JP2007154376A - Dust sheet excellent in cleaning property - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dust sheet increasing the uptake of the dust on a floor such as hairs, cigarettes, ash, sand, soil, etc., improving the dust-collecting property and holding property by reducing the amount of discharge of the taken up dust to improve cleaning property. <P>SOLUTION: This dust sheet consists of a non-woven fabric obtained by laminating a mixed short fiber layer consisting of a polyester short fiber and a polyolefin short fiber on the fiber layer obtained by a spun-bonding method and performing an interlace-treatment to make them one unit, and has ≥1.5 N/5 cm<SP>2</SP>50% compressive stress and also 5-15% range 50% compressive stress relaxation rate. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention mainly relates to a dust sheet having good dust collection and dust retention, such as hair and powder on the floor, tobacco ash, and earth and sand, and excellent cleaning properties.

  In cleaning the floor, a dust sheet based on a nonwoven fabric is widely used to clean the floor by attaching it to a mop and moving it while applying an appropriate force to the mop pattern. However, since dust on the floor contains various foreign substances such as hair, dust, sand, and cigarette ash, it must have excellent trapping properties. Dust sheets once collect dust. Dust retention so that it does not fall off is also required.

However, the characteristics of collecting and holding dust are not uniform depending on the type of dust, and therefore, the collection and holding properties according to these various dusts are required, and the fibers that are added to or constitute the dust sheet Was heat-sealed to improve the collection and retention. However, since these dust sheets require chemical treatment and complicated manufacturing methods, there is a difficulty in increasing the cost, and the present applicant has previously proposed a dust sheet that is inexpensive and excellent in dust collection and retention. (For example, see Patent Document 1)
This dust sheet is a sheet in which long fiber layers and short fiber layers are laminated and integrated by entanglement of fibers, and the surface friction coefficient of the short fiber layer is 0.5 or less, and the shear modulus of the dust sheet Is a dust sheet of 60 g / cm ² · 100% or more.
Japanese Patent Laid-Open No. 2004-283501

However, the applicant further examined the mechanism of dust removal, and studied the concept. The applicant responded to each function such as dust collection, scraping, and entanglement, and each required characteristic was different. It has been found that the cleaning effect is still insufficient in part with the coefficient of friction and shear modulus on the surface of the short fiber layer. The present invention is based on the above knowledge, and in addition to the above characteristics, the 50% compressive stress and 50% compressive stress relaxation rate of the sheet are further collected in the dust removing mechanism by finding that they have a large role in the cleaning function. The object is to provide a more effective cleaning function in response to scraping, entanglement, etc., and to improve dust collection efficiency.

That is, the dust sheet of the present invention for achieving the above object is a nonwoven fabric obtained by laminating a short fiber layer on a fiber layer obtained by a spunbond method, and performing an entanglement treatment to integrate the nonwoven fabric. The sheet has a 50% compressive stress of 1.5 N / 5 cm ² or more and a 50% compressive stress relaxation rate in the range of 5 to 15%.

  Here, the fiber layer obtained by the spunbond method is preferably a polyester long fiber layer, and the laminated short fiber layer is a mixture of polyester short fibers and polyolefin short fibers, and the polyolefin short fibers Is preferably in the range of 15 to 80% by mass.

In the dust sheet of the present invention, the amount of uptake can be increased by increasing the 50% compression stress to 1.5 N / 5 cm ² or more, and the 50% compression stress relaxation rate is maintained at 5 to 15%. As the dust is reduced, the cleaning effect of hair on the floor, cigarettes and ash, earth and sand, etc. is more efficient than conventional ones. Has excellent dust collection and dust retention.

  Hereinafter, specific embodiments of the present invention will be described in detail.

The dust sheet of the present invention is made of a nonwoven fabric obtained by laminating short fiber layers on a fiber layer obtained by the spunbond method and entangled and integrated. Especially, the 50% compressive stress is 1.5 N / 5 cm ² or more, and 50% The dust collecting property and dust holding property are enhanced by setting the compression stress relaxation rate in the range of 5 to 15%.

  The dust sheet of the present invention is based on a dust removal mechanism (wiping mechanism) as a basic concept. As a result, the fiber elastic modulus strength is an important factor for scraping. In addition, for scraping, static and fiber flexibility are important factors, and fine denier and low elastic modulus fibers are suitable, and the combination of polymers constituting the fibers is also relevant. In addition, it has been found that solid crimped fibers and bulky fibers are suitable for the dust entanglement from the fiber entanglement, and based on these ideas, considering the dust constituent fiber and compression set rate, etc., 50% compression Knowing that it is effective to specify the stress and 50% compressive stress relaxation rate, the present invention has been achieved.

  In the dust sheet of the present invention, a nonwoven fabric in which a short fiber layer is laminated on a fiber layer obtained by a spunbond method as a nonwoven fabric constituting the dust sheet, and subjected to an entanglement treatment and integrated is used. Here, as the fiber layer obtained by the spunbond method, any fiber that can be spunbonded can be used, but it is usually a long fiber layer, and among them, a polyester long fiber layer is practically used. Natural fibers and synthetic fibers can be used as the fibers constituting the short fiber layer. However, in the dust sheet of the present invention, a mixture of polyester short fibers and polyolefin short fibers such as polypropylene short fibers is used. Is preferably used. In this case, the spunbond fiber is preferably in the range of 10 to 33% as a blend of the fiber by the spunbond method and the short fiber. If it is 10% or less, the base fabric effect of spunbond fibers (long fibers) is lost. On the other hand, if it exceeds 33%, the number of fibers on the short side of the mixed fibers is reduced, so that dust retention is poor. Therefore, the range of 10 to 33% is preferable.

  On the other hand, as a blend of the polyester and each polyolefin short fiber in the mixed fiber short fiber layer, the polyolefin short fiber is preferably in the range of 15 to 80% by mass. If the amount is 15% by mass or less, the polyolefin fiber is small, so that the dust collecting and holding effect is weak. On the other hand, if it exceeds 80% by mass, the effect of the polyester fiber is small, the set rate is increased, and the dust holding is reduced. Accordingly, polyolefin fibers, practically polypropylene fibers, are used, but 15 to 80% by mass is preferable.

  The fineness of each of the polyester and polyolefin fibers used is not particularly limited, including the case of spunbond, and may be a fineness within a generally used range, usually 1.0 to 30 dtex, preferably Is 2-15 dtex. When it is 1.0 dtex or less, the performance of scraping and holding dust is poor, and when it is 30 dtex or more, there is a difficulty in lacking in performance of holding dust because it is too thick.

On the other hand, the fineness of polyolefin fibers such as polypropylene fibers and polyethylene fibers may be substantially the same as described above, and is 1.0 to 30 dtex, preferably 2 to 15 dtex. The basis weight of the fiber layer composed of lamination of the obtained fiber layer and the combined filament short fiber layer by the spunbond method 25~200g / m ^2, especially preferably 40~150g / m ^2, a basis weight 25 g / m ² or less In this case, the amount of dust is limited due to the balance between the short fibers and the fibers by the spunbond method, and when the basis weight is 200 g / m ² or more, the amount of dust is limited due to the balance between the two fibers.

  Next, since the density of the fiber layer by the above-mentioned lamination is determined by the basis weight and the thickness, if the basis weight range is determined, the subsequent is the thickness range. The thickness is for securing a volume for holding dust, and a range in which the compression modulus is exhibited is preferable, and 0.5 mm to 2.5 mm, particularly 0.8 mm to 2.5 mm is preferable. When the thickness is 0.5 mm or less, it is not preferable to secure a volume for holding dust, and when the thickness is 3.5 mm or more, the volume for holding dust becomes excessive.

Thus, in the present invention, the laminated fiber layer having the fiber configuration as described above is subjected to the entanglement process, and is integrated into the nonwoven fabric by the entanglement of the fibers. There are various types of processing, such as needle punching and water jet processing, but the most common is needle punching. Adjust the needle type (thickness), needle depth, and number of hammers as appropriate. Is done. The dust sheet of the present invention is formed as a sheet having the characteristics that the 50% compressive stress of the integrated nonwoven fabric is 1.5 N / 5 cm ² or more and the 50% compressive stress relaxation rate is in the range of 5 to 15%. Is done.

The 50% compressive stress of the nonwoven fabric indicates the state of the nonwoven fabric fibers when the mop moves on the floor surface, and the amount of dust taken up varies depending on the 50% compressive stress. When the 50% compressive stress is small, the dust uptake is small. Conversely, when the 50% compressive stress is large, the dust uptake is large. Therefore, the 50% compressive stress that makes the state of the nonwoven fabric suitable is at least 1.5 N / 5 cm ² or more. On the other hand, the 50% compressive stress relaxation rate of the non-woven fabric indicates the state of the fiber before and after the mop moves on the floor surface. If it is large, the dust that has been taken in will come out. In this sense, the 50% compressive stress relaxation rate that makes the nonwoven fabric fiber suitable is in the range of 5% to 15%. Therefore, in the dust sheet of the present invention, the range in which the 50% compression stress of the nonwoven fabric is 1.5 N / 5 cm ² or more and the 50% compression stress relaxation rate is 5 to 15% is specified.

The following method is used for producing the dust sheet as described above. That is, first, a short fiber layer made of polyester and polyolefin and a polyester long fiber obtained by a spunbond method are laminated, and needle processing is performed from the short fiber layer to the long fiber layer, and then from the long fiber layer to the short fiber layer. The needle is processed from the short fiber layer as necessary. Needle processing conditions at this time are determined by the type of needle, the needle depth and the number of driven needles. The needle processing conditions are prepared according to the above-described processing conditions with a basis weight of 25 to 200 g / m ² and a thickness of 0.5 to 3.5 mm. Then, the final dust sheet of the present invention is obtained by winding up as a desired size. Examples are given below.

Example 1
80% by mass of polyester fiber (PET fiber) with a fineness of 2.2 decitex (dtex) and a fiber length of 51 mm and 20% by mass of polypropylene fiber (PP fiber) with a fineness of 2.2 dtex and fiber length of 64 mm are uniformly mixed. Fibers are processed to form a short fiber layer having a basis weight of about 35 g / m ^2. Continuously, the short fiber layer is obtained by a spunbond method (SB) with a fineness of 2.2 dtex and a basis weight of 15 g. / M ² polyester is laminated on the long fiber layer, and the needle punching machine is then used to treat the spunbond long fiber layer from the long fiber layer to the short fiber layer at a needle depth of 9 mm and a driving number of 35 / cm ^2. needle depth 11mm from the fiber layer, implantation and treated with number 65 present / cm ^2, further needle depth 6.5mm from the long fiber layer spunbond, end counts 65 present / c The ^second needling continuously subjected to obtain a dust sheet of the present invention.
(Example 2)
Polyester fiber 20% by mass with a fineness of 2.2 decitex (dtex) and a fiber length of 51 mm and 80% by mass of a polypropylene fiber with a fineness of 2.2 decitex (dtex) and a fiber length of 64 mm are uniformly mixed and carded. A short fiber layer having a basis weight of about 35 g / m ^{2 is formed, and} the short fiber layer is continuously laminated on a polyester long fiber layer having a basis weight of 15 g / m ² with a fineness of 2.2 dtex obtained by the spunbond method. Then, the needle punching machine processed the spunbond from the long fiber layer to the short fiber layer at a needle depth of 9 mm and a driving number of 35 / cm ² , and then the needle depth of 11 mm and the driving number of 65 from the short fiber layer. This is processed with a needle / cm ² , and further, needle processing with a needle depth of 6.5 mm and a driving number of 65 / cm ² is continuously applied from the spunbond long fiber layer. An inventive dust sheet was obtained.
(Example 3)
50% by mass of polyester fiber having a fineness of 2.2 decitex (dtex) and a fiber length of 51 mm and 50% by mass of polypropylene fiber having a fineness of 6.6 decitex (dtex) and a fiber length of 64 mm are uniformly mixed and carded. A short fiber layer having a basis weight of about 35 g / m ^{2 was formed, and} the short fiber layer was continuously laminated on a long fiber layer of polyester having a basis weight of 15 g / m ² with a fineness of 2.2 dtex obtained by the spunbond method. Using a needle punch machine, the spunbond long fiber layer is processed from the short fiber layer to the short fiber layer at a needle depth of 9 mm and the number of driven wires is 35 / cm ² , and then from the short fiber layer is 11 mm and the needle depth is 65 wires / cm. ² and further continuously processing needles with a needle depth of 6.5 mm and a driving number of 65 / cm ² from the long fiber layer of spunbond. A sheet was obtained.
(Comparative Example 1)
A polyester fiber having a fineness of 2.2 decitex (dtex) and a polyester fiber having a fiber length of 51 mm is formed into a short fiber layer having a basis weight of about 30 g / m ² by carding, and the short fiber layer is continuously obtained by the spunbond method. .2 Dettex (dtex) is laminated on a polyester long fiber layer having a basis weight of 15 g / m ² , and subsequently needle spun machine from the long fiber layer of spunbond to the short fiber layer has a needle depth of 9 mm and the number of driven 35 / the process of cm ^2, then the needle depth 11mm from the short fiber layer, implantation and treated with number 65 present / cm ^2, further needle depth 6.5mm from the long fiber layer spunbond, end counts 65 present / cm ² A comparative dust sheet was obtained by continuously performing the needle processing.
(Comparative Example 2)
A polyester fiber having a fineness of 22.2 dtex and a polyester fiber having a fiber length of 51 mm is formed into a short fiber layer having a basis weight of about 30 g / m ² by carding, and the short fiber layer is continuously obtained by the spunbond method. .2 Dettex (dtex) is laminated on a polyester long fiber layer having a basis weight of 15 g / m ² , and subsequently needle spun machine from the long fiber layer of spunbond to the short fiber layer has a needle depth of 9 mm and the number of driven 35 / the process of cm ^2, then the needle depth 11mm from the short fiber layer, implantation and treated with number 65 present / cm ^2, further needle depth 6.5mm from the long fiber layer spunbond, end counts 65 present / cm ² A comparative dust sheet was obtained by continuously performing the needle processing.
(Comparative Example 3)
A commercial non-woven fabric in which a mixed fiber layer of short polyester fiber, a core-sheath short fiber made of polyester and modified polypropylene, and a long polyester fiber layer obtained by a spunbond method was used as a comparative dust sheet.

  Thus, the above-obtained dust sheet of the present invention and the comparative dust sheet were evaluated for characteristics and cleaning. The results are shown in Table 1.

上記表中の５０％圧縮応力，５０％圧縮応力緩和率は下記により測定した。
（１）５０％圧縮応力
圧縮試験は東洋ボールドイン社製５０Ｋｇテンシロンを用い、圧縮面積１０．０ｃｍφで圧縮速度２ｍｍ／ｍｉｎで試料を５０％まで圧縮し、試料の圧縮変形率５０％の応力を測定する。得られた応力を圧縮面積で除し単位面積当たりに換算して示した。測定回数はｎ＝３の平均で示し、単位はＮ／ｃｍ²である。
（２）５０％圧縮応力緩和率
圧縮試験は東洋ボールドイン社製５０Ｋｇテンシロンを用い、圧縮面積１０．０ｃｍφで、圧縮速度２ｍｍ／ｍｉｎで試料を５０％まで圧縮し（変形応力：ＨＮ）、３分間維持してその時の圧縮応力（ｈＮ）を測定する。次式により圧縮応力緩和率を計算する。測定回数はｎ＝３の平均で示し、単位は％である。

The 50% compressive stress and 50% compressive stress relaxation rate in the above table were measured as follows.
(1) 50% compressive stress In the compression test, a 50Kg Tensilon manufactured by Toyo Bald-In Co., Ltd. was used. The sample was compressed to 50% at a compression area of 10.0 cmφ and a compression rate of 2 mm / min. taking measurement. The obtained stress was divided by the compression area and expressed per unit area. The number of measurements is shown as an average of n = 3, and the unit is N / cm ² .
(2) 50% compressive stress relaxation rate In the compression test, a 50 kg Tensilon manufactured by Toyo Bald-In Co., Ltd. was used, and the sample was compressed to 50% at a compression area of 10.0 cmφ and a compression rate of 2 mm / min (deformation stress: HN). Maintain the minute and measure the compressive stress (hN) at that time. The compression stress relaxation rate is calculated by the following formula. The number of measurements is shown as an average of n = 3, and the unit is%.

Stress relaxation rate (R) = (h / H) × 100 (%)
Moreover, the cleaning evaluation of the dust sheets of Examples and Comparative Examples was performed and evaluated based on the following.
・ Cleaning evaluation (1) Floor (surface finish Isamu floor V hard acrylic dustproof paint (Isamu Paint Co., Ltd.))
(2) 3M dust mop (DKIT-M effective width: 9cm, length: 61cm, weight 970g)
(3) Dust is (b) hair, (b) cigarette and ash, (c) earth and sand (mixed ratio of JIS KS4.5.6)
・ Evaluation (1) A sample is attached to a 3M dust mop.
(2) The floor surface had a width of 65 cm and a length of 5 m.
(3) Dust evenly in a range of 55 cm wide and 30 cm long in front.
(4) Gently place a dust mop in front of evenly scattered dust. (5) Gently wipe the handle gently in one direction at an angle of about 30 degrees and gently lift it up to measure the amount of dust entangled in the sample sheet. To do.

集塵率（塵取り面積１００ｃｍ²、目付１００ｇ当たり）
Ｄ＝（（Ｐｄ／Ｔｄ）／（Ｓ×Ｍ））×（１００×１００）（％）
Ｄ：集塵率（％）
Ｓ：試料の実接した面積（ｃｍ²）（本テスト：５４９ｃｍ²）
Ｐｄ：試料に付着したダスト量（ｇ）
Ｔｄ：床に散布したダスト量（ｇ）
Ｍ：試料の目付（ｇ／ｍ²）
１００：１００（ｃｍ²） 面積
１００：１００（ｇ／ｍ²）目付
以上の結果より、前記表1に示す如く本発明による５０％圧縮応力ならびに５０％圧縮応力緩和率の範囲は清掃性に極めて関連性を有してダスト捕集性とダスト保持性に優れた効果を発揮することが分かる。

Dust collection rate (Dust removal area 100cm ² , per unit weight 100g)
D = ((Pd / Td) / (S × M)) × (100 × 100) (%)
D: Dust collection rate (%)
S: Actual contact area of the sample (cm ² ) (this test: 549 cm ² )
Pd: amount of dust adhering to the sample (g)
Td: amount of dust spread on the floor (g)
M: Sample weight (g / m ² )
100: 100 (cm ² ) Area 100: 100 (g / m ² ) Based on the above results, as shown in Table 1, the range of 50% compressive stress and 50% compressive stress relaxation rate according to the present invention is extremely clean. It can be seen that it has a relevance and exhibits an excellent effect in dust collection and dust retention.

Claims (3)

A non-woven fabric obtained by laminating a short fiber layer on a fiber layer obtained by a spunbond method and performing an entanglement treatment, and the non-woven fabric has a 50% compressive stress of 1.5 N / 5 cm ² or more. And the dust sheet excellent in the cleanability characterized by 50% compressive-stress relaxation rate being 5 to 15% of range.   2. The dust sheet having excellent cleaning properties according to claim 1, wherein the fiber layer obtained by the spunbond method is a polyester long fiber layer.   The dust sheet excellent in cleaning properties according to claim 1 or 2, wherein the short fiber layer to be laminated is composed of a mixture of polyester short fibers and polyolefin short fibers, and the content of the polyolefin short fibers is in the range of 15 to 80% by mass.