JP2000314065A - Cleaning nonwoven fabric and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cleaning nonwoven fabric capable of easily wiping off solid or tacky deposits on the surface to be cleaned without damaging the surface and having high ability to scavenge any dirts, and to provide a method for producing the above fabric. SOLUTION: This cleaning nonwoven fabric 1 is obtained by the following process: at least one side of a 1st fibrous layer comprising heat-shrinkable fibers is laminated with a 2nd fibrous layer comprising non-heat-shrinkable fibers; the resulting laminate is subjected to a high-pressure fluid jet against the 2nd fibrous layer side to form a nonwoven fabric with the fibers intermingled together; the nonwoven fabric is then subjected to hot press treatment with a hot-embossing roll to effect partial hot-pressure bonding of both the fibrous layers along with heat shrinkage of the heat-shrinkable fibers, thus forming hot-pressure bonded parts 2 where the fibers are thermobonded together to effect increase in the thickness of non-hot-pressure bonded parts 3 where the constituent fibers look as if they are raised loop-fashion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nonwoven fabric for cleaning which can be easily wiped off without damaging attached matter such as solids and sticky substances on a surface to be cleaned, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, as a cleaning material using a nonwoven fabric, a type in which fine dirt is wiped off with a nonwoven fabric using an ultrafine fiber such as a splittable conjugate fiber as disclosed in JP-A-4-33686, JP-A-7
Japanese Patent Application Laid-Open No. 3598 discloses roughly a nonwoven fabric surface having irregularities to physically take in dirt or the like, or a type in which an abrasive or the like is attached to polish the surface of an object.

[0003]

However, the cleaning material has the following problems. If the nonwoven fabric is made of ultra-fine fibers, fine dirt and sticky substances such as oil can be wiped off, but dirt gets clogged immediately in the fiber voids. Will spread. If it is a type that entangles dust by entanglement of fibers or a type that has irregularities on the surface of the nonwoven fabric,
Although a moderately small solid such as hair can be entangled, the strength of the surface of the nonwoven fabric is weak against dirt or sticky matter stubbornly adhered to the object, and it cannot be sufficiently scraped off. The type with abrasives etc. is effective for dirt and sticky substances that adhered stubbornly to the target, but other types of dirt would only scratch the surface of the target and would not catch it. Insufficient gathering effect. Therefore, the present invention has been made in view of such circumstances, and can easily wipe off attached matter such as solids and sticky substances without damaging the surface to be cleaned, and is excellent in capturing all kinds of dust. An object of the present invention is to provide a cleaning nonwoven fabric having a concentrating ability and a method for producing the same.

[0004]

Means for Solving the Problems To solve the above problems,
Therefore, the cleaning nonwoven fabric of the present invention contains a heat-shrinkable fiber.
Non-heat-shrinkable fiber is contained on at least one side of the first fiber layer
The second fiber layer is laminated and three-dimensionally entangled
A non-woven fabric, wherein the non-woven fabric is a fiber
A thermocompression bonding part formed by thermocompression bonding is formed.
3g / cm of non-woven fabric ^TwoThickness under load is H_ThreeAnd the adjacent heat
The average distance between the thermocompression bonding portions formed between the crimping portions was D.
At the time, the bulging ratio (H_Three/ D) is 0.4 or more
There is a feature. By adopting such a configuration,
Damage to the surface to be cleaned against any dirt and debris
Can be easily wiped off without any
Is obtained.

When the thickness of the cleaning nonwoven fabric of the present invention under a load of 3 g / cm ² is H ₃ and the thickness under a load of 20 g / cm ² is H ₂₀ , the thickness ratio (H ₂₀ / H ₃ ) is 0. It is desirably 80 or more.

In the present invention, the non-heat-shrinkable fibers of the second fiber layer are desirably water-absorbing and / or oil-absorbing fibers.

In the present invention, it is desirable that the first fiber layer is formed by mixing 20 to 80% by weight of the heat-shrinkable fiber and 80 to 20% by weight of the non-heat-shrinkable fiber of the second fiber layer.

[0008] The non-heat-shrinkable fiber of the second fiber layer is a sheath-core type composite fiber, and the thermoplastic resin of the sheath component is of the same type as the resin forming the heat-shrinkable fiber of the first fiber layer. Desirably, the resin is made of

In the cleaning nonwoven fabric of the present invention, a second fiber layer containing a non-heat-shrinkable fiber is laminated on at least one surface of a first fiber layer containing a heat-shrinkable fiber, and a high-pressure fluid flow is applied to the second fiber layer. 2 After spraying from the fiber layer side to form a non-woven fabric in which the fibers are entangled with each other, heat and pressure treatment is performed using a heating embossing roll, and both fiber layers are partially thermocompression-bonded, and the heat-shrinkable fiber is It can be manufactured by heat-shrinking to form a thermocompression-bonded portion in which fibers are thermally bonded to each other. Further, it is preferable that the heating and pressurizing treatment by the heating embossing roll is performed between the embossing roll and the flat roll so that the first fiber layer abuts on the embossing roll side. Hereinafter, the contents of the present invention will be specifically described.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The first fiber layer of the cleaning nonwoven fabric of the present invention is not particularly limited as long as it contains fibers exhibiting shrinkage behavior. Shrinkable fibers or latently crimpable conjugate fibers that shrink in appearance are preferred. For example, apparently heat-shrinkable side-by-side composite fibers or eccentric core-sheath composite fibers composed of a combination of polyester / copolyester, polypropylene / ethylene-propylene copolymer, polypropylene / ethylene-butene-propylene terpolymer, and the like. Or copolymerized polyester, ethylene-
Propylene copolymer, ethylene-butene-propylene 3
Latent heat-shrinkable fibers composed of a prepolymer. These fibers are at least 20% by weight in the first fiber layer
It is preferred to contain.

In particular, the first fiber layer preferably contains at least 20% by weight of a heat-shrinkable fiber having a maximum shrinkage of at least 50% upon heating. More preferably, the heat shrinkable fiber has a maximum heat shrinkage of at least 80% at least 30% by weight. Here, the maximum shrinkage refers to the highest shrinkage in the shrunk state of the heated fiber while maintaining the fiber shape. If the shrinkage ratio of the heat-shrinkable fiber is less than 50%, the shrinkage is insufficient, and a clear nonwoven fabric having peaks and valleys cannot be obtained. Further, even if the shrinkable fibers have a shrinkage of about 80%, a desired nonwoven fabric cannot be obtained if other fibers are mixed with 70% or more.

As the heat-shrinkable fiber satisfying the above requirements, for example, a fiber made of a polymer containing at least 70% by weight of an ethylene-propylene random copolymer having a melting point Tm (° C.) of 130 <Tm <145 is preferable. The above-mentioned melting point is defined as the D when a differential calorimetry (DSC) of a polymer is performed.
The temperature at which the SC curve shows the highest value. 13 melting point
If the temperature is lower than 0 ° C., the polymer will exhibit rubber-like elasticity, and the fiber will have poor card passing properties. On the other hand, if the temperature exceeds 145 ° C., the heat shrinkage of the fiber becomes about the same as ordinary polypropylene, which is not preferable. The proportion of the ethylene-propylene random copolymer is 70% by weight.
If it is less than 50%, the maximum shrinkage of the obtained fiber is less than 50%, which is not preferable. As the polymer to be mixed with the ethylene-propylene random copolymer, it is preferable to use an ethylene-propylene-butene-1 terpolymer or a polyolefin-based polymer such as polypropylene.

In the first fiber layer, other fibers mixed with the heat-shrinkable fibers include, for example, cotton, silk,
Wool, natural fibers such as pulp, regenerated fibers such as rayon,
Any one or more of semi-synthetic fibers such as acetate, acrylic fibers, polyamide fibers such as nylon 6 and nylon 66, polyester fibers such as polyethylene terephthalate and polybutylene terephthalate, and polyolefin fibers such as polyethylene and polypropylene. Can be selected and used. For example, it is preferable to use a heat-adhesive fiber having a temperature close to the melting point of the heat-shrinkable fiber because the fiber web is heat-bonded when heat-treated. Examples of such a heat-adhesive fiber include polyethylene / polypropylene, polyethylene / polyethylene terephthalate,
Copolyester / polyethylene terephthalate, ethylene-propylene copolymer / polypropylene, ethylene-propylene copolymer / polyethylene terephthalate, ethylene-vinyl acetate copolymer / polypropylene,
Examples include sheath-core type composite fibers such as ethylene-methyl acrylate copolymer / polypropylene, but are not limited thereto.

When the same fiber as the non-heat-shrinkable fiber of the second fiber layer is used as the other fiber mixed with the heat-shrinkable fiber, the function of the non-heat-shrinkable fiber is also used in the first fiber layer. In addition to having the heat-shrinkable fiber, the heat-shrinkable fiber has a mixing ratio of 20 to 80% by weight and the non-heat-shrinkable fiber 8 of the second fiber layer.
Conveniently 0-20% by weight.

Further, when a water-absorbing fiber is used as another fiber mixed with the heat-shrinkable fiber, when the cleaning non-woven fabric of the present invention is used as a wet cleaning material, it has an adverse effect on the liquid-absorbing property and retention of a chemical solution. It is preferable because of its superiority. As the water-absorbing fiber, for example, cotton, silk, wool, pulp,
Fibers such as rayon. Among them, rayon fiber is preferable from the viewpoint of handleability and versatility.

Examples of the form of the first fiber layer include a parallel web made of staple fibers, a cross web, a semi-random web, a random web, a long fiber web made of continuous filaments, a web obtained by wet-making short fibers, and a melt blown nonwoven fabric. Any of them may be used, but among them, in order to strengthen the entanglement with the second fiber layer by a three-dimensional entanglement treatment described later, it is preferable to use a fiber web made of staple fibers. The first fiber layer is
The fibrous web may be laminated with the second fiber layer as it is, but there is no problem if the fibers are lightly entangled or joined in advance as a nonwoven fabric. The preferred basis weight of the first fiber layer is 5 to 50 g / m ² , more preferably 10 to 40 g / m ² . When the basis weight is less than 5 g / m ² , unevenness in heat shrinkage occurs, and when the basis weight exceeds 50 g / m ² ,
This is because the basis weight of the obtained product increases.

Next, the second fiber layer will be described. Second
The material constituting the fiber layer is not particularly limited as long as it can form a fiber aggregate and contains non-heat-shrinkable fibers that do not substantially shrink at the temperature at which the first fiber layer shrinks. Not done. The non-heat-shrinkable fibers of the second fiber layer are preferably water-absorbing and / or oil-absorbing fibers. Examples of the water-absorbing fibers include natural fibers such as cotton, silk, wool, and pulp, and rayon. And the like, and the oil-absorbing fibers include polyester fibers such as polyethylene terephthalate and polybutylene terephthalate, and polyolefin fibers such as polyethylene and polypropylene. Examples of the fibers having both functions include acrylic fibers, polyamide fibers such as nylon 6 and nylon 66, and fibers obtained by hydrophilizing the oil-absorbing fibers. In the present invention, one or more of these can be arbitrarily selected and used. In addition, the fiber shape and the like are not particularly limited, and a single fiber, a sheath-core composite fiber, a split composite fiber, a fiber having an irregular cross section, or the like can be arbitrarily used.

For example, if water or oil is frequently used, such as in a kitchen or factory, it is preferable to selectively use fibers having both of the above functions. In particular, acrylic fibers having an irregular cross section are preferably used. It is most effective from the viewpoint of water absorption / oil absorption and wiping properties. The fineness is 0.5-2.5
It is preferably dtex.

When used for solid matter such as bird droppings sticking to an object, it is preferable to use a sheath-core type composite fiber, and it is preferable that the second fiber layer contains at least 50% by weight. . More preferably, it is 70% by weight or more. When the content in the second fiber layer is less than 50% by weight, the heat bonding strength between the fibers in the second fiber layer is weak, the fibers are caught on the solid matter, the nonwoven fabric itself is fluffed, or the fibers are cut and fall off. This is because there is fear. Examples of the combination of composite fibers include polyethylene / polypropylene, polyethylene / polyethylene terephthalate, copolymerized polyester / polyethylene terephthalate, ethylene-propylene copolymer / polypropylene, and ethylene-propylene copolymer / polyethylene terephthalate. In particular, the melting point of the sheath component thermoplastic resin
Ts (° C) is the melting point Tm (° C) of the heat-shrinkable fiber of the first fiber layer
It is preferable that Tm−20 ≦ Ts ≦ Tm + 10. If Ts is less than Tm-20, the heat-shrinkable fiber may not be sufficiently shrunk, so that it is necessary to raise the processing temperature, thereby not only melting too much and making the texture too hard, but also Workability also deteriorates. If it exceeds Tm + 10, the non-thermocompression-bonded portion cannot be hardened, and the wiping property against solids is poor. Particularly preferably, the thermoplastic resin of the sheath component is a resin of the same type as the resin forming the heat-shrinkable fibers of the first fiber layer. This is because using the same type of resin is excellent in terms of appropriate workability and the surface hardness of the non-thermocompression bonded part.

The form of the second fiber layer is also not particularly limited, and may be a parallel web or cross web made of staple fibers, a semi-random web, a long fiber web made of continuous filaments, a web made by short-fiber wet-making, a melt blown nonwoven fabric, or the like. Can be used arbitrarily. In order to strengthen entanglement with the first fiber layer, it is preferable to use a web made of staple fibers. The second fiber layer may be laminated with the first fiber layer as it is as the fiber web, or may be a nonwoven fabric in which fibers are lightly entangled or bonded in advance. The preferred basis weight of the second fiber layer is 10 to 100 g / m ² , and more preferably 15 to 50 g / m ² . When the basis weight is less than 10 g / m ² , the wiping properties are insufficient, and when the basis weight exceeds 100 g / m ² , the basis weight of the obtained product becomes large.

Then, the first fiber layer and the second fiber layer are laminated and integrated by a three-dimensional entanglement process described later. The three-dimensional confounding process is performed by a high-pressure fluid flow process or a needle punching process. In the present invention, the high-pressure fluid flow process is preferable because the degree of confounding is large. The “fluid” here is not limited as long as the fibers can be entangled with each other, but water is particularly preferably used in terms of process control. The pressure of the fluid flow to be jetted may be set according to the basis weight and the degree of entanglement of the web to be processed. For example, 20
When processing webs of １００100 g / m ² , the pressure of the fluid stream is preferably from 1 to 10 MPa. If it is less than 1 MPa, the energy of the fluid flow is weak, and the fibers cannot be sufficiently entangled. If it exceeds 10 MPa, the formation of the web is disturbed, and a uniform nonwoven fabric cannot be obtained.

The obtained entangled nonwoven fabric is subjected to a heating and pressurizing treatment using a heating embossing roll, so that both fiber layers are partially thermocompression-bonded, and at the same time, the heat-shrinkable fibers on the first fiber layer side are thermally shrunk. Thus, a thermocompression-bonded portion formed by thermally bonding the fibers is formed. The heating and pressurizing treatment by the heating embossing roll may be performed at a temperature at which the heat-shrinkable fibers in the first fiber layer shrink. In particular, when the wiping surface is to be hardened, a sheath for forming the second fiber layer is formed. The treatment is preferably performed at a temperature not lower than the temperature at which the thermoplastic resin of the sheath component of the core type composite fiber is melted. By performing the heating and pressurizing treatment, the thickness of the non-thermocompression-bonded portion increases, and the constituent fibers assume a form as if protruded into a loop shape shown in FIG. 1, for example, a mushroom type, a hook type, or the like. When used as a cleaning nonwoven fabric, the peripheral portion formed by the deep mountain valleys can scrape stubborn deposits such as bird droppings and dead insects and sticky substances such as oil stains. 1 in FIG. 1 is a cleaning nonwoven fabric,
Reference numeral 2 denotes a thermocompression bonding portion, and 3 denotes a non-thermocompression bonding portion. Furthermore, since the ratio of the constituent fibers oriented in the thickness direction is large, the nonwoven fabric has an appropriate thickness change (sagging property) in the thickness direction,
The scraped dirt can be taken into the non-thermocompression bonding portion without damaging the surface of the object. Further, the thermocompression bonding portion formed on the surface of the second fiber layer due to the heat shrinkage of the first fiber layer does not directly reflect the shape of the small protrusion of the embossing roll, and has various directions as shown in FIG. It is deformed to a size and formed in a non-uniform shape, which obviously has a shape different from the conventional thermocompression bonding nonwoven fabric shown in FIGS.

The heating and pressurizing treatment is carried out by passing a laminate subjected to a three-dimensional entanglement treatment between a heating embossing roll and a heating flat roll. Embossing rolls include those with a large number of small round or polygonal protrusions on the roll surface, those with circular or polygonal depressions on the roll surface, and regular irregularities formed in the width direction of the roll. And the like having a set gear shape can be used.
At this time, it is preferable that the first fiber layer be treated on the embossing roll side so that the surface of the nonwoven fabric is hardened and the property of scraping off attached matter is improved. It is preferable that the number of the thermocompression bonding portions formed by thermally bonding the fibers in the nonwoven fabric is 8 pieces / cm ² or more. More preferably, the number is 30 to 60 particles / cm ² . If the proportion of the thermocompression-bonded portion is less than 8 pieces / cm ² , sufficient nonwoven fabric strength cannot be obtained, and the scraping properties of solids and the like are also insufficient.

The area shrinkage of the non-woven fabric due to the heat and pressure treatment is preferably 30% or more. More preferably, it is 40 to 80%. This is because if the area shrinkage is less than 30%, the non-thermocompression bonding portion is not sufficiently raised. The preferred basis weight of the cleaning nonwoven fabric of the present invention is 30 to 200 g / m ² , more preferably 40 to 200 g / m ^2.
100 g / m ² . When the basis weight is less than 30 g / m ² , the wiping properties are insufficient, and when the basis weight exceeds 200 g / m ² ,
This is because not only the handling becomes difficult, but also the cost increases.

The cleaning nonwoven fabric thus obtained is
Assuming that the average distance between the thermocompression bonding portions formed between the adjacent thermocompression bonding portions is D, the bulging ratio (H ₃ / D) of the non-thermocompression bonding portion is 0.4 or more. The kimono can be easily wiped without damaging the surface to be cleaned, resulting in a nonwoven fabric having excellent collecting ability.
More preferably, it is 0.55 or more. As shown in FIG. 3, the distance between the thermocompression bonding portions is a straight line that passes through the vicinity of the center of the adjacent thermocompression bonding portions in the longitudinal direction (vertical direction) of the nonwoven fabric. Refers to the distance between the ends closer to. In addition, the bulging ratio (H ₃ / D) of the non-thermocompression bonding portion is a ratio of the width to the height of the non-thermocompression bonding portion, and can be used as an index indicating the shape of the non-thermocompression bonding portion. The higher this ratio, the higher the height of the non-thermocompression bonding section having a towering cross section. Conversely, the lower this ratio, the lower the peak of the non-thermocompression bonding section having a gentler cross section. If the protuberance ratio (H ₃ / D) of the non-thermocompression bonded part is less than 0.4, the adhered substance or the adhesive substance is not sufficiently caught on the valley formed by the non-thermocompression bonded part and the thermocompression bonded part, and is scraped off. Poor sex.

Further, assuming that the thickness of the cleaning nonwoven fabric under a load of 3 g / cm ² is H ₃ , H ₃ is preferably 1 mm or more. More preferably, it is 1.2 mm or more. If H ₃ is less than 1 mm, sufficient cleaning power cannot be obtained. When the thickness of the cleaning nonwoven fabric under a load of 3 g / cm ² is H ₃ and the thickness under a load of 20 g / cm ² is H ₂₀ , the thickness ratio (H ₂₀ / H ₃ ) is 0.80-0. .95. More preferably, it is 0.85 to 0.95.
The thickness ratio (H ₂₀ / H ₃ ) is an index indicating the height of the peripheral portion formed at the peaks and valleys and the sag in the thickness direction of the nonwoven fabric, and the higher the ratio, the larger the height of the peripheral portion. In addition, it has small settability, and a mountain and valley shape suitable for scraping stubborn deposits and sticky substances and wiping dust is obtained. Thickness ratio (H ₂₀ / H ₃₎ is 0.
If it is less than 80, the set is too large and the scraping property is insufficient.

[0027]

EXAMPLES Hereinafter, the contents of the present invention will be specifically described with reference to examples. The average distance between thermocompression-bonded portions, thickness, tensile strength, elongation at break, and wiping performance of the obtained nonwoven fabric were measured as follows.

[Average distance between thermocompression bonding portions] Three sample pieces each having a width of 2.5 cm and a length (longitudinal direction) of 2.5 cm are prepared, and thermocompression bonding is performed adjacent to the nonwoven fabric in the longitudinal direction (vertical direction). The parts were tied with a straight line so as to pass near the center of the parts, and the distance between the ends closer to each thermocompression bonding part was measured and averaged.

[Thickness] Thickness measuring machine (trade name: THICKNESS
Using a GAUGE model CR-60A (manufactured by Daiei Kagaku Seiki Seisaku-Sho, Ltd.), measurement was performed under a load of 3 g and 20 g per 1 cm ^{2 of} the sample, and the measured values were H ₃ and H ₂₀ , respectively.

[Tensile strength, elongation at break] JIS L10
According to 96, a sample piece having a width of 5 cm and a length of 15 cm is gripped at a spacing of 10 cm, and is stretched at a pulling speed of 30 cm / min using a constant-speed stretching type tensile tester. Tensile strength and breaking elongation were used.

[Wiping Performance] (1) Wiping Performance for Solids Glass having a glass surface as an object, 0.3 g of laundry paste (manufactured by Silver Chemical Industry Co., Ltd.) applied uniformly over a range of 3 cm × 3 cm. The surface was left in a dryer at 70 ° C. for 10 minutes to dry and solidify the laundry paste. Then, the sample cut into a size of 10 cm × 10 cm was impregnated with about 200% of water, and was squeezed tightly to adjust the water content to about 100%. Then, the sample was folded in four so that the second fiber layer surface became a wiping surface. 2 on the glass surface
Five reciprocations were performed with a constant load of kg, and the wiping properties were visually evaluated as follows.

(2) Wiping performance for adhesives Heat resistant lubricating paste (Dow Corning
1 g of a product (Moricoat, manufactured by Asia Co.) was evenly applied, and a sample cut to a size of 10 cm × 10 cm was impregnated with about 200% of water, squeezed tightly, and squeezed tightly to obtain a water content of about 10%.
After adjusting to 0%, the second fiber layer was folded in four so that the surface became a wiping surface, and the glass surface was reciprocated 5 times with a constant load of 2 kg, and the wiping property was visually evaluated as follows. ◎ ・ ・ ・ Wipe off very well ○ ・ ・ ・ Roughly wiped down △ ・ ・ ・ Slightly left unwiped ×× Many left unwiped

Examples 1 to 3 As the first fiber layer, the melting point
A parallel web having a basis weight of 10 g / m ^{2 and} a heat shrinkable fiber (manufactured by Daiwa Spinning Co., Ltd.) having a fineness of 2.2 dtex and a fiber length of 51 mm made of an ethylene-propylene random copolymer having a Tm of 138 ° C. was produced. The fiber exhibited a dry heat shrinkage (maximum heat shrinkage) of 92% when left in an atmosphere at 150 ° C. for 1 minute. Dry heat shrinkage rate, bundle 50 fibers,
Marks were made at predetermined intervals with a black cotton thread, exposed to an atmosphere at a temperature of 150 ° C. for about 30 seconds, and the intervals at which the marks were made were measured and calculated. Here, measurement is performed at a temperature higher than the melting point.
Since the treatment time is short, the fiber can be shrunk while maintaining the fiber shape.

As the second fiber layer, the sheath component has a melting point Ts of 13
It is composed of an ethylene-propylene random copolymer at 8 ° C and a sheath-core type heat-adhesive conjugate fiber (manufactured by Daiwa Spinning Co., Ltd.) having a core component of polyethylene terephthalate having a melting point of 265 ° C and a fineness of 4.4 dtex and a fiber length of 51 mm. A parallel web having a basis weight of 25 g / m ² was produced.

Next, these webs were laminated, and the pore size was set at 0.
A high-pressure columnar water stream with a water pressure of 3 MPa was jetted twice from front and back, respectively, from a nozzle having 12 mm orifices perforated at 0.6 mm intervals, and the fibers were three-dimensionally entangled to form an entangled nonwoven fabric. The obtained entangled nonwoven fabric was embossed (heat surface area 0.785) at 125 ° C. (Example 1), 130 ° C. (Example 2), and 135 ° C. (Example 3).
mm ² frusto-conical small protrusion pattern, 25 pieces / cm ² ) and a flat roll are subjected to thermocompression bonding at a linear pressure of 50 kg / cm so that the first fiber layer is in contact with the embossing roll with a clearance of 0 mm between the rolls. Then, the first fiber layer was thermally shrunk to form deep peaks and valleys in the second fiber layer.

Example 4 Example 1 was used as the first fiber layer.
Of 50% by weight of a heat-shrinkable fiber of the above and 50% by weight of acrylic fiber (trade name K-615, manufactured by Nippon Exlan Co., Ltd.) having a fiber length of 51 mm and a fiber length of 0.9 dtex.
A parallel web of g / m ² was produced. As the second fiber layer,
A parallel web having a basis weight of 25 g / m ^{2 made} of the acrylic fiber was produced. Next, a second fiber layer was laminated on both surfaces of the first fiber layer to form a three-layer structure, and subjected to high-pressure water flow treatment under the same conditions as in Example 1 to obtain an entangled nonwoven fabric. The obtained entangled nonwoven fabric was subjected to thermocompression bonding at 140 ° C. and a linear pressure of 50 kg / cm, and the first fiber layer was thermally shrunk to form deep peaks and valleys in the second fiber layer.

[Comparative Example 1] A sheath-core composite fiber having a fineness of 2.2 dtex and a fiber length of 51 mm (ethylene-propylene random copolymer having a melting point of 138 ° C as a sheath component and polypropylene having a melting point of 163 ° C as a core component) was used. A parallel web having a basis weight of 40 g / m ² made of Daiwa Spinning Co., Ltd. was prepared, and an embossing roll heated to 135 ° C. (a small projection pattern of a truncated cone having a top surface area of 0.785 mm ² , 25 pieces / cm ²⁾ ) And flat roll, clearance between rolls 0mm, linear pressure 50kg / cm
To form a thermocompression-bonded nonwoven fabric. Example 1
Table 1 shows the physical properties of Comparative Example 4 and Comparative Example 1.

[0038]

[Table 1]

In Examples 1 to 3, the thickness ratio was increased and the wiping property against solids was improved. Also, it was more effective for the adhesive to have a moderate set. In Example 4, since acrylic fiber was used,
The surface of the nonwoven fabric was also soft, and was particularly effective against sticky substances. On the other hand, in Comparative Example 1, a large amount of unwiped residue was left, which was insufficient as a nonwoven fabric for cleaning.

[0040]

The cleaning non-woven fabric of the present invention can be used for removing all kinds of dirt and deposits, especially stubborn solids and adhesives, by setting the ridge ratio (H ₃ / D) of the non-thermocompression-bonded portion within a predetermined range. On the other hand, it can be easily wiped without damaging the surface to be cleaned, and has excellent trapping ability. further,
By setting the thickness ratio in a predetermined range, the surface has an appropriate settability, so that the scraped dirt can be taken in without damaging the surface of the object.

[Brief description of the drawings]

FIG. 1 shows an example of a cross section of the cleaning nonwoven fabric of the present invention.

FIG. 2 shows an example of the surface of the cleaning nonwoven fabric of the present invention.

FIG. 3 shows an example of a cross section of a conventional thermocompression bonding nonwoven fabric.

FIG. 4 shows an example of the surface of a conventional thermocompression bonding nonwoven fabric.

[Explanation of symbols]

 1. 1. Nonwoven fabric for cleaning Thermocompression bonding part 3. Non-thermocompression part 4. Distance between thermocompression bonding parts

Claims (7)

[Claims] 1. A nonwoven fabric comprising a second fiber layer containing non-heat-shrinkable fibers laminated on at least one surface of a first fiber layer containing heat-shrinkable fibers and three-dimensionally entangled, The nonwoven fabric has a thermocompression bonded portion formed by bonding fibers by partial thermocompression bonding, and 3 g / cm ^{2 of the} nonwoven fabric is formed.
When the thickness under load is H ₃ and the average distance between the thermocompression bonding portions formed between adjacent thermocompression bonding portions is D, the bulging ratio (H ₃ / D) of the non-thermocompression bonding portion is 0.4 or more. A nonwoven fabric for cleaning characterized by the following. ^2. When the thickness of the nonwoven fabric under a load of 3 g / cm ² is H ₃ and the thickness under a load of 20 g / cm ² is H ₂₀ , the thickness ratio (H ₂₀ / H ₃ ) is 0.80 or more. The cleaning nonwoven fabric according to claim 1, wherein the cleaning nonwoven fabric is provided. 3. The nonwoven fabric for cleaning according to claim 1, wherein the non-heat-shrinkable fibers of the second fiber layer are water-absorbing and / or oil-absorbing fibers. 4. The heat-shrinkable fiber according to claim 1, wherein the first fiber layer is a heat-shrinkable fiber.
% By weight and 80 to 20% by weight of the non-heat-shrinkable fiber of the second fiber layer
Characterized in that they are mixed with each other.
2. The nonwoven fabric for cleaning according to item 1. 5. The non-heat-shrinkable fiber of the second fiber layer is made of a sheath-core conjugate fiber, and the thermoplastic resin of the sheath component is made of the same type as the resin forming the heat-shrinkable fiber of the first fiber layer. The cleaning nonwoven fabric according to any one of claims 1 to 3, wherein the cleaning nonwoven fabric is a resin. 6. A second fiber layer containing a non-heat-shrinkable fiber is laminated on at least one surface of a first fiber layer containing a heat-shrinkable fiber, and a high-pressure fluid flow is jetted onto the second fiber layer from the second fiber layer side. Then, after forming a non-woven fabric in which the fibers are entangled with each other, a heating and pressing treatment is performed using a heating embossing roll, and both the fiber layers are partially thermocompression-bonded, and the heat-shrinkable fibers are thermally contracted, and A method for producing a nonwoven fabric for cleaning, characterized in that a thermocompression-bonded portion formed by heat bonding is formed. 7. The heating and pressurizing treatment by the heating embossing roll is performed so that the first fiber layer abuts on the embossing roll side between the embossing roll and the flat roll. Manufacturing method of nonwoven fabric for cleaning.