JP3934916B2 - Stretchable nonwoven fabric and method for producing the same - Google Patents

Description

表１より、実施例１〜３で得られた各伸縮性不織布は、比較例で得られた不織布に比べて、縦横の両方向の伸長回復率が極めて高くなり、複数方向における伸縮性に優れた不織布となることがわかる。
【００７９】
なお、比較例では、伸長回復率が縦（ＭＤ）４９．９％、横（ＣＤ）４５．６％と低く、伸縮性不織布としては不適である。
【００８０】
【発明の効果】
本発明によれば、弾性繊維と捲縮繊維との交絡点をバインダーにより接合するようにしているので、風合いがよく、柔軟性に優れ、伸縮を繰り返しても伸縮性が劣化しない伸縮性不織布を得ることができる。
【００８１】
また、弾性繊維と捲縮繊維とがランダム配向されるようにすると、複数方向において伸縮性を得ることができ、球体等に対する曲面追随性を向上させることができる。したがって、洋服の芯地、外用薬の基布、ワイピングクロス、包装材等のような伸縮性の必要な用途に好適な伸縮性不織布を得ることができる。
【図面の簡単な説明】
【図１】本発明の一実施例の伸縮性不織布を示す斜視図である。
【図２】図１におけるIIＡ−IIＡ線拡大断面図およびIIIＡ−IIIＡ線拡大断面図である。
【図３】伸縮性不織布の製造装置を示す模式図である。
【図４】（Ａ）加熱前のウェブおよび（Ｂ）加熱後のウェブを示す図解図である。
【符号の説明】
(10)…伸縮性不織布
(12)…弾性繊維
(14)…捲縮繊維
(16)…繊維状バインダー[0001]
[Industrial application fields]
The present invention relates to a stretchable nonwoven fabric. More specifically, it has a good texture, has flexibility and elasticity in multiple directions (vertical, horizontal, and diagonal), does not deteriorate even when it is repeatedly expanded and contracted, and has a uniform thickness. It is related with a nonwoven fabric and its manufacturing method.
[0002]
[Prior art]
Conventionally, various techniques for imparting stretchability to a nonwoven fabric have been proposed.
[0003]
As such a technique, first, a technique for manufacturing a stretchable nonwoven fabric mainly using rubber-based elastic fibers is known. For example, Japanese Patent Publication No. 43-26578 and Japanese Patent Laid-Open No. 3-19952 disclose a technique for forming a stretchable nonwoven fabric by interlacing polyurethane elastic fibers with each other. Japanese Patent Application Laid-Open No. 10-25621 discloses a technique in which a polyester elastic fiber containing a sulfonic acid metal salt and an anti-sticking agent is made into a stretchable nonwoven fabric by a wet papermaking method.
[0004]
The stretchable nonwoven fabric obtained by these techniques is mainly composed of rubber-based elastic fibers, and thus has a high stretchability and a high recovery rate of stretch. However, the touch becomes sticky and sticky like rubber, and the texture is inferior, making it difficult to use for clothing and sanitary materials that directly touch the skin.
[0005]
Next, a technique for producing a stretchable nonwoven fabric by interlacing crimped fibers made of polyester, polypropylene, or the like is known. For example, in Japanese Patent Laid-Open No. 2-91217 and Japanese Patent Laid-Open No. 5-171555, a web made of latent crimped fibers formed by the card method is mechanically entangled and then subjected to heat treatment to express crimps. A technique for obtaining a stretchable nonwoven fabric is shown.
[0006]
The stretchable nonwoven fabric obtained by these techniques is improved in texture, but when it is repeatedly stretched, there is a problem that mechanical entanglement is lost and the stretchability is lowered. In these techniques, the card method is used for forming the web, and the fibers are easily oriented in the longitudinal direction. As a result, the expansion and contraction of the nonwoven fabric is effective only in the longitudinal direction. Therefore, when a sphere or the like is wrapped as a packaging material, there is a problem that the curved surface followability is inferior.
[0007]
In order to solve this problem, for example, Japanese Patent Application Laid-Open No. 8-260313 and Japanese Patent Application Laid-Open No. 11-61617 disclose a technique for making a web orthogonal by a cross layer or the like. However, this technique does not eliminate a decrease in stretchability when repeated stretching and webs are laminated, resulting in problems such as increased basis weight and lack of flexibility.
[0008]
Furthermore, a technique for manufacturing a stretchable nonwoven fabric by joining a nonwoven fabric and a stretchable member is known. Japanese Patent Application Laid-Open No. 8-188950 discloses a technique for performing a high-pressure water injection process on a laminate in which an elastic elastic member is interposed between two upper and lower webs.
[0009]
In the stretchable nonwoven fabric obtained by this technique, the texture of the nonwoven fabric is improved, and the stretch directionality and the stretch properties when the stretch is repeated are also improved. However, since the elastic elastic member is interposed between the web layers, the thickness becomes non-uniform, and in order to make this thickness uniform, there is a problem that the basis weight of the nonwoven fabric must be increased and the flexibility is lacking. Furthermore, since the elastic stretchable member is interposed after the web is once formed, the process becomes complicated, and the loss is large in terms of quality control and manufacturing cost.
[0010]
[Problems to be solved by the invention]
Therefore, the object of the present invention is good in texture, has flexibility and elasticity in multiple directions (vertical, horizontal, and diagonal), and does not deteriorate even when it is repeatedly expanded and contracted. It is to provide a stretchable nonwoven fabric that is uniform, and to provide a method for producing such a stretchable nonwoven fabric.
[0011]
[Means for Solving the Problems]
A first aspect of the present invention is an elastic fiber (12), and latent crimp fibers expressing crimp by heating at a temperature lower than the softening point of the elastic fibers (12) (14), elastic fibers (12) intertwined points between the latent crimped fibers entangled points or elastic fibers (14) (12) and the latent crimp fiber (14) fibrous binder for bonding with interlacing point (16) and the elastic nonwoven fabric comprising ( 10) The fibrous binder (16) has a sheath part (16x) and a core part (16y), and the melting point of the sheath part (16x) is the crimp expression temperature of the latent crimped fiber (14). It is an elastic nonwoven fabric (10) characterized by being lower than the above.
[0012]
2nd invention is a manufacturing method of the elastic nonwoven fabric (10) provided with an elastic fiber (12) and a latent crimp fiber (14) , Comprising: An entanglement point with an elastic fiber (12) , a latent crimp fiber ( 14) or the elastic fiber (12) and the entangled point with the latent crimped fiber (14) are joined with a fibrous binder (16), and then the expansion or contraction that causes the crimped latent fiber to develop. This is a method for producing a conductive nonwoven fabric (10).
[0013]
In the stretchable nonwoven fabric (10) of the first invention and the stretchable nonwoven fabric (10) obtained by the second invention, the elastic fiber (12) and the crimped fiber (14) are bonded at the entanglement point (16). It is joined via. Therefore, even if these fibers are short fibers, a flexible nonwoven fabric having excellent mechanical strength and low basis weight can be realized. Further, since the elastic fiber (12) excellent in stretch recovery property and the crimped fiber (14) which gives bulkiness and flexibility by crimping are joined, a nonwoven fabric (10) having both advantages can be obtained. Can do.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIGS. 1 and 2, the stretchable nonwoven fabric (10) to which the present invention is applied includes elastic fibers (12), crimped fibers (14), and a binder (16) that are randomly oriented.
[0015]
The elastic fiber (12) is such that the fiber itself, such as polyurethane elastic fiber, has rubber-like elasticity.
[0016]
The single yarn fineness and length of the elastic fiber (12) are determined from the viewpoint of product strength and moldability, and the single yarn fineness is preferably 0.5 dtex or more and 40 dtex or less, more preferably, 1 dtex or more and 30 dtex or less. When the single yarn fineness is less than 0.5 decitex, the mechanical strength of the elastic fiber (12) is weak, and conversely, when it is larger than 40 decitex, the elastic fiber constituting the web per unit area ( This is because the number of 12) is reduced, and in any case, the stretch recovery performance inherent to the elastic fiber is hardly exhibited.
[0017]
On the other hand, the length of the elastic fiber (12) is preferably 3 mm or more and 50 mm or less, more preferably 5 mm or more and 30 mm or less. When the fiber length is less than 3 mm, the dispersibility of each fiber is improved, but the mechanical strength of the nonwoven fabric is weakened. Conversely, when the fiber length is larger than 50 mm, the mechanical strength of the nonwoven fabric is increased but the web is strong. This is because it becomes difficult to uniformly disperse the fibers during molding.
[0018]
The cross-sectional shape of the elastic fiber (12) is not particularly limited, and may be a circular cross-section as shown in FIG. 2 or an irregular cross-section such as a triangle or a flat shape.
[0019]
As the elastic fiber (12), in addition to the polyurethane elastic fiber, a polyether / ester elastic fiber, a polyamide elastic fiber, or the like can be used, and a so-called rubber thread made of natural rubber, synthetic rubber, semi-synthetic rubber, or the like is used. It can also be used. Also, composite fibers or mixed fibers of these elastic fibers and other organic synthetic resins can be used.
[0020]
However, in order to obtain a flexible nonwoven fabric excellent in elongation recovery performance, it is preferable to use polyurethane elastic fibers (12).
[0021]
As such a polyurethane elastic fiber, a long-chain diol such as a copolyester diol as a main constituent component as a soft segment, a diisocyanate such as diphenylmethane-4,4 diisocyanate as a main constituent component, and a bifunctional as a chain extender As a chain extender, a polyester-based elastic fiber having a basic hydrogen compound as a main component, polytetramethylene ether glycol as a main component as a soft segment, and diphenylmethane-4,4 diisocyanate as a main component as a hard segment Examples thereof include polyether elastic fibers having a low molecular weight bifunctional hydrogen compound as a main constituent.
[0022]
The crimped fiber (14) is obtained by crimping a polyester fiber or the like mechanically or with a specific fiber structure to give the fiber itself elasticity like a coil spring.
[0023]
The single yarn fineness and length of the crimped fiber (14) are determined from the viewpoint of product function, product strength and moldability, and the single yarn fineness is preferably 0.2 dtex or more and 20 dtex or less, More preferably, it is 0.5 dtex or more and 10 dtex or less. When the single fiber fineness of the crimped fiber (14) is less than 0.2 dtex, a dense and flexible nonwoven fabric can be obtained, but the stretchability is inferior, and conversely, when it is greater than 20 dtex, This is because the nonwoven fabric has elasticity but is inferior in rigid texture.
[0024]
On the other hand, the length of the crimped fiber (14) is preferably 3 mm or more and 50 mm or less, more preferably 5 mm or more and 30 mm or less, for the same reason as in the case of the elastic fiber (12). .
[0025]
The cross-sectional shape of the crimped fiber (14) is not particularly limited, and may be a circular cross-section as shown in FIG. 2 or an irregular cross-section such as a triangle or a flat shape.
[0026]
The crimped fibers (14) include polyester fibers, synthetic fibers such as polyolefins, acrylics and polyamides, semi-synthetic fibers such as triacetate fibers and diacetate fibers, viscose rayon, copper Regenerated cellulose fibers such as ammonia rayon and polynosic rayon, and natural fibers such as cotton, silk, wool and hemp can be used. In other words, any fiber can be crimped (approached crimp) by guiding the fiber yarn to a crimper or the like and mechanically crimping it. The kind of crimped fiber (14) is not particularly limited.
[0027]
However, in order to improve the mixability with other fibers in the production process of the stretchable nonwoven fabric (10) and the stretchability, texture and thickness uniformity of the stretchable nonwoven fabric (10) as a product, (14) is preferably a latently crimped fiber that develops crimps by a relaxation heating treatment after mixing, and when using latently crimped fibers, the types of fibers are limited to some extent.
[0028]
Such latent crimped fibers include, for example, a plurality of types of thermoplastic polymer components (polyester, polyolefin, acrylic, polyamide, etc.) having different heat shrinkage characteristic values such as melting point and viscosity, A structure arranged side by side along the length direction (side-by-side structure) and these multiple types of thermoplastic polymer components (polyester, polyolefin, acrylic, polyamide, etc.) are eccentric in the cross section of the yarn fiber The thing of the structure arrange | positioned at core-sheath shape is known.
[0029]
In the latent crimped fiber (14), it is preferable that the crimp expression temperature is lower than the softening point of the elastic fiber (12). If the crimping temperature of the latent crimped fiber (14) is higher than the softening point of the elastic fiber (12), the process of heating the latent crimped fiber (14) to develop the crimp in the elastic fiber (12) This is because the elongation recovery performance deteriorates.
[0030]
Such a latent crimped fiber (14) has a side-by-side structure latent crimp mainly composed of polyethylene terephthalate (14x) as a high melting point component and ethylene terephthalate / isophthalic acid copolymer (14y) as a low melting point component. Mention may be made of the fibers (14).
[0031]
The binder (16) is made of a polyester resin, a polyolefin resin, an acrylic resin, a polyamide resin, etc., fluidized by heating and melting, moved to the entanglement point of the fibers constituting the web, and cooled and solidified. The entanglement point is joined.
[0032]
The melting point of the binder (16) is preferably lower than the softening point of the elastic fiber (12). This is because if the melting point of the binder (16) is higher than the softening point of the elastic fiber (12), the stretch recovery performance of the elastic fiber (12) deteriorates in the step of heating and melting the binder (16).
[0033]
In addition, the binder (16) can exert its function as long as it is fluidized by heating and melting, so the shape thereof is not particularly limited, and the fibrous shape shown in FIG. 1 and FIG. In addition, it may be liquid or powder.
[0034]
However, from the viewpoint of reliably joining the entanglement points of the fibers, the shape of the binder (16) is preferably fibrous, and in particular, the sheath (16x) made of a low-melting thermoplastic resin. A fibrous binder (16) having a core-sheath structure including a core (16y) having a higher melting point than the sheath (16x) is preferable.
[0035]
The use of the core-sheath fibrous binder (16) has the following advantages. That is, when the sheath part (16x) is melted in the heating process (fiber entanglement point joining process) of the fibrous binder (16), the melted resin of the sheath part (16x) becomes the fiber of the core part (16y). Move along and gather at the fiber entanglement point (18) by surface tension. And the entanglement point of a fiber is joined by cooling and solidifying this resin. For this reason, the resin of the sheath part (16x) does not spread in a planar shape, and there is no concern that the stretchability of the elastic fiber (12) or the crimped fiber (14) is hindered.
[0036]
As the fibrous binder (16) having such a core-sheath structure, the sheath part (16x) is formed of a low melting point ethylene terephthalate / isophthalic acid copolymer, and the core part (16y) is formed more than the sheath part (16x). Examples thereof include those formed of high melting point polyethylene terephthalate.
[0037]
The cross-sectional shape of the fibrous binder (16) may be a shape in which the sheath (16x) and the core (16y) are arranged concentrically as shown in FIG. The shape may be arranged in an eccentric circle (not shown).
[0038]
The length of the fibrous binder (16) is preferably 3 mm or more and 50 mm or less, more preferably 5 mm, for the same reason as in the case of the elastic fiber (12) and the crimped fiber (14). Above and below 30 mm.
[0039]
In order to effectively exhibit the various functions of the stretchable nonwoven fabric (10), the blending ratio of each constituent fiber is preferably within the following range.
[0040]
That is, the blending ratio of the elastic fiber (12) is preferably 3% by weight or more and 50% by weight or less, more preferably 5% by weight or more and 30% by weight or less.
[0041]
When the blending ratio of the elastic fiber (12) is less than 3% by weight, the stretch recovery performance inherent to the elastic fiber (12) is hardly exhibited. Conversely, when the blending ratio is more than 50% by weight, the touch is rubber. This is because it becomes sticky and sticky, and the texture becomes inferior.
[0042]
The blending ratio of the crimped fiber (14) is preferably 40% by weight or more and 80% by weight or less, more preferably 50% by weight or more and 70% by weight or less.
[0043]
When the blending ratio of the crimped fibers (14) is less than 40% by weight, the stretchability of the nonwoven fabric is lowered, and the nonwoven fabric has a hard texture with poor flexibility. Conversely, when the blending ratio is more than 80% by weight, This is because, although it has stretchability, the mechanical strength is weakened, so that the stretch recovery performance when repeatedly stretched is lowered.
[0044]
Furthermore, the blending ratio of the binder is preferably 10% by weight or more and 50% by weight or less, more preferably 20% by weight or more and 40% by weight or less.
[0045]
When the blending ratio of the binder is less than 10% by weight, the mechanical strength of the nonwoven fabric is weak, and conversely, when it exceeds 50% by weight, the mechanical strength increases but the stretchability is inhibited. This is because it is hard and inferior in texture.
[0046]
When the elastic fibers (12), the crimped fibers (14) and the binder (16) are randomly oriented according to the above blending ratio, the stretchable unwoven cloth (10) is oriented in a plurality of longitudinal, lateral and diagonal directions. Can be expanded and contracted.
[0047]
The stretchable nonwoven fabric (10) is manufactured using a manufacturing apparatus A as shown in FIG.
[0048]
The manufacturing apparatus A includes a rotary device (20), a mixing tank (22), a machine tank (24), a short net paper machine (26), a felt (28), a cylinder dryer (30), a feed roller (31), Including the heating furnace (32), take-up roller (34), winding device (36), etc., the `` fiber mixture preparation process '' is executed in the rotary device (20), mixing tank (22) and machine tank (24) Then, the “web forming step” is executed by the short net paper machine (26), and the “fiber entanglement step” is executed by the felt (28) and the cylinder dryer (30). Then, the “crimping process” is executed by the feed roller (31), the heating furnace (32), and the take-up roller (34), and the “winding process” is executed by the winding device (36).
[0049]
Below, the method to manufacture an elastic nonwoven fabric (10) using the manufacturing apparatus A is demonstrated. However, in the following example, latent crimped fibers are used as the crimped fibers (14), and a fibrous binder is used as the binder (16).
[0050]
First, in the “fiber mixture preparation step”, the elastic fiber (12), the latent crimped fiber (14), and the fibrous binder (16) are put into water, and these are rotated by a rotary device (20) such as a pulper. The fibers are mixed and disaggregated and dispersed to prepare a fiber mixture suspension (hereinafter referred to as “mixture”) having a concentration of about 0.1 to 3%. Then, this mixture is sequentially transferred to the mixing tank (22) and the machine tank (24) by a pump.
[0051]
In the subsequent `` web forming process '', the mixture in the machine tank (24) is supplied to the wire transport band (26a) provided in the short net paper machine (26) by a pump, Is dehydrated. By this step, water in the mixture is removed, and a web is formed on the wire transport band (26a). Since the fibers in the mixture are sufficiently mixed in the previous step, the constituent fibers of the web are randomly oriented in a plurality of directions as shown in FIG. Then, the web on the wire conveyance band (26a) is transferred onto the felt (28) having a higher surface smoothness than the wire conveyance band (26a).
[0052]
In the next “fiber entanglement joining step”, the web transferred onto the felt (28) is transferred onto a cylinder dryer (30) having a surface smoothness higher than that of the felt (28) and heated to a predetermined temperature. The
[0053]
When the web is heated, the fibrous binder (16) constituting the web is melted, and the melted resin flows to the fiber entanglement point (18) by surface tension. When the web is pulled away from the cylinder dryer (30) and cooled, the melted resin is solidified to join the entanglement points (18). Therefore, the web that has undergone the “fiber entanglement bonding step” has greatly increased mechanical strength.
[0054]
In the “crimp expression step”, the web is supplied by the feed roller (31) to the heating furnace (32) using radiant heat such as infrared rays or far infrared rays. The temperature in the heating furnace (32) is set to a temperature that is lower than the softening point of the elastic fiber (12) and that allows the latent crimped fiber (14) to be crimped.
[0055]
Here, in order to express the crimp in the latent crimped fiber (14), it is preferable that the web in the heating furnace (32) is in a relaxed state, and therefore the feed roller (31) so that the web is not tensioned. And the peripheral speed of the take-up roller (34) is adjusted.
[0056]
In the final “winding step”, the completed stretchable nonwoven fabric (10) is wound by the winding device (36).
[0057]
In addition, each process mentioned above is only an example to which this invention is applied, and the following changes may be added.
[0058]
That is, in the “fiber mixture preparation step”, a nonionic neutral polyether-based dispersant, a weak cation neutral modified polyester / polyether-based dispersant, etc. are added to the total weight of the fiber in order to assist the dispersion of each fiber in the mixture. May be added in the range of 0.01 wt% to 10%, or a commercially available water-soluble adhesive may be added in an amount of 5 ppm to 50 ppm in terms of solid content with respect to the weight of the mixture.
[0059]
Further, the number of tanks (mixing tank (22) and machine tank (24)) for storing the mixture may be one, or three or more.
[0060]
In the “web forming step”, another type of paper machine such as a long net or a circular net may be used instead of the short net paper machine. Further, the length and number of the felt (28) for conveying the formed web may be appropriately changed, and one or more rolls may be used in place of the felt (28).
[0061]
Moreover, you may provide separately the "press process" which squeezes between a "web shaping | molding process" and a "fiber entanglement point joining process."
[0062]
Furthermore, in the “fiber entanglement point joining step”, instead of the cylinder-type dryer (30), other types of heating devices such as an air dryer, an air-through dryer, an infrared dryer, or a suction dryer may be used.
[0063]
In addition, the “fiber entanglement point joining step” and the “crimp expression step” may be executed at different times or places, and these steps are integrated to join the fiber entanglement point and crimp appearance. May be performed simultaneously.
[0064]
In addition, the texture and surface properties of the stretchable nonwoven fabric (10) are adjusted by a calender roll (not shown), an emboss roll (not shown), etc. between the “crimp expression step” and the “winding step”. An “adjustment step” may be provided separately.
[0065]
Further, in the “fiber mixture preparation step” and the “web forming step”, other liquids such as ethanol may be used as a dispersion medium instead of water.
[0066]
Furthermore, in the “fiber mixture preparation step” and the “web molding step”, a dry method using a gas such as air as the dispersion medium may be employed instead of the wet method using water as the dispersion medium. In this case, in the “fiber mixture preparation step”, each fiber is disaggregated and dispersed by a defibrating machine (not shown), and a mixture of each fiber is prepared by a blending machine (not shown). On the other hand, in the “web forming step”, each fiber is randomly oriented in a plurality of directions by a random card machine.
[0067]
(Example)
EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the examples.
[0068]
In addition, the physical property in an Example and a comparative example was measured with the following method.
(1) Weight per unit area: Measured according to JIS L-1096.
(2) Thickness: Measured according to JIS L-1096.
(3) Tensile strength: Measured according to JIS P-8113.
(4) CD / MD ratio: an index indicating fiber orientation in the nonwoven fabric. For the tensile strength in the machine direction (MD) along the product flow and the tensile strength in the transverse direction (CD) perpendicular to this, the transverse (CD) strength was divided by the longitudinal (MD) strength and expressed as a ratio.
(5) Elongation recovery rate: an index indicating the remaining stretchability after repeated stretch. For the specimen after giving 15% elongation recovery 5 times with an Instron testing machine, the elongation (%) was measured again with the Instron testing machine, and this was divided by the elongation before giving the extension recovery, Expressed as a percentage (%).
[0069]
Example 1
Polyurethane elastic fiber (“Lycra (registered trademark)” manufactured by Toray DuPont, product number T-127C) having a single yarn fineness of 7 dtex, a fiber length of 6 mm, and a softening point of about 180 ° C. is prepared as an elastic fiber. As a crimped fiber, a latent crimped polyester fiber (T81 manufactured by Unitika Fiber Co., Ltd.) having a single yarn fineness of 1.7 dtex, a fiber length of 5 mm, and a crimp expression temperature of about 140 ° C. or more is prepared. As a binder, a polyester core-sheath binder fiber having a single yarn fineness of 1.1 dtex, a fiber length of 3 mm, and a sheath melting point of about 110 ° C. (“Melty (registered trademark)” manufactured by Unitika Fiber Co., Ltd., product number 4080) Prepared.
[0070]
Then, 5% by weight of polyurethane elastic fiber, 65% by weight of latently crimped polyester fiber, and 30% by weight of polyester core-sheath binder fiber are uniformly dispersed in water using a pulper, and a PAM-based adhesive (Mitsui Cytec Co., Ltd.). "Myresin (Registered Trademark)", product number R10L) made from 10ppm of the weight of the mixture, and modified polyester / ether dispersant (MDP-002 made by Takemoto Yushi Co., Ltd.) added at 1% of the total fiber weight A mixture having a fiber concentration of about 0.5% was prepared.
[0071]
Subsequently, the mixture was made with a short paper machine so that the fibers were randomly oriented in a plurality of directions, and then heated with a cylinder dryer having a surface temperature of 120 degrees to form a web having a basis weight of 22 g / m ² . Obtained.
[0072]
Then, the web is brought into a relaxed state, and this is passed through an infrared heater set at 160 ° C. to develop crimps, and then treated with a flat roller set at a linear pressure of 10 kgf / cm to obtain a stretchable nonwoven fabric. It was. The properties of the resulting stretchable nonwoven fabric are shown in Table 1.
[0073]
(Example 2)
A stretchable nonwoven fabric was obtained under the same conditions as in Example 1 except that the blending ratio of the polyurethane elastic fiber was 10% by weight and the blending ratio of the latent crimped polyester fiber was 60% by weight. Table 1 shows the properties of the obtained nonwoven fabric.
[0074]
(Example 3)
A stretchable nonwoven fabric was obtained under the same conditions as in Example 1 except that the blending ratio of the polyurethane elastic fibers was 20% by weight and the blending ratio of the latent crimped polyester fibers was 50% by weight. Table 1 shows the properties of the obtained nonwoven fabric.
[0075]
(Comparative example)
In the comparative example, a nonwoven fabric was formed without blending elastic fibers.
[0076]
That is, as a crimped fiber, a single crimped fineness of 1.7 decitex, a fiber length of 5 mm, a latent crimped polyester fiber having a crimp expression temperature of about 140 ° C. or more (T81 manufactured by Unitika Fiber Co., Ltd.), As a binder, a polyester core-sheath binder fiber having a single yarn fineness of 1.1 dtex, a fiber length of 3 mm, and a sheath melting point of about 110 ° C. (“Melty (registered trademark)” manufactured by Unitika Fiber Co., Ltd., product number 4080) Prepared.
[0077]
Then, 70% by weight of latent crimped polyester fiber and 30% by weight of polyester core-sheath binder fiber were uniformly dispersed in water using a pulper, and an elastic nonwoven fabric was obtained by the same production method as in Example 1. Table 1 shows the properties of the obtained nonwoven fabric.
[0078]
[Table 1]

From Table 1, each stretchable nonwoven fabric obtained in Examples 1 to 3 has an extremely high elongation recovery rate in both the longitudinal and lateral directions, and is excellent in stretchability in a plurality of directions, compared to the nonwoven fabric obtained in the comparative example. It turns out that it becomes a nonwoven fabric.
[0079]
In the comparative example, the elongation recovery rate is as low as 49.9% in the vertical direction (MD) and 45.6% in the horizontal direction (CD), which is not suitable as a stretchable nonwoven fabric.
[0080]
【The invention's effect】
According to the present invention, since the entanglement point between the elastic fiber and the crimped fiber is joined by the binder, a stretchable nonwoven fabric that has a good texture, excellent flexibility, and does not deteriorate stretchability even after repeated stretches. Obtainable.
[0081]
In addition, when the elastic fibers and the crimped fibers are randomly oriented, stretchability can be obtained in a plurality of directions, and curved surface followability to a sphere or the like can be improved. Therefore, it is possible to obtain a stretchable nonwoven fabric suitable for uses requiring stretchability, such as clothes interlining, a base cloth for external medicine, a wiping cloth, and a packaging material.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a stretchable nonwoven fabric according to an embodiment of the present invention.
2 is an enlarged sectional view taken along line IIA-IIA and an enlarged sectional view taken along line IIIA-IIIA in FIG.
FIG. 3 is a schematic view showing an apparatus for producing a stretchable nonwoven fabric.
FIG. 4 is an illustrative view showing (A) a web before heating and (B) a web after heating.
[Explanation of symbols]
(10)… Elastic nonwoven fabric
(12)… elastic fiber
(14)… Crimp fiber
(16)… Fibrous binder

Claims (8)

Intertwined points of the elastic fibers, and latent crimp fibers expressing crimp by heating at a temperature lower than the softening point of the elastic fibers, the previous SL intertwined points of the elastic fibers, the latent Mekuchijimi繊Wei or the a elastic fibers and the latent crimp fibers and stretched or squeezed nonwoven Ru and a fibrous binder for bonding with entangled points of
The said fibrous binder has a sheath part and a core part, The melting | fusing point of the said sheath part is lower than the crimp expression temperature of the said latent crimp fiber, The elastic nonwoven fabric characterized by the above-mentioned . The stretchable nonwoven fabric according to claim 1, wherein the elastic fibers and the latent crimped fibers are randomly oriented. The elastic nonwoven fabric according to claim 1 or 2, wherein the elastic fiber has a length of 3 mm or more and 50 mm or less . The stretchable nonwoven fabric according to any one of claims 1 to 3, wherein a single yarn fineness of the elastic fiber is 0.5 dtex or more and 40 dtex or less . The stretchable nonwoven fabric according to any one of claims 1 to 4, wherein the crimped fiber has a length of 3 mm or more and 50 mm or less . The stretchable nonwoven fabric according to any one of claims 1 to 5, wherein the crimped fiber has a single yarn fineness of 0.2 dtex or more and 20 dtex or less . (A) It has an elastic fiber, a latent crimp fiber that develops crimps by being heated at a temperature lower than the softening point of the elastic fiber, a sheath part and a core part, and the melting point of the sheath part is Mixing with a fibrous binder lower than the crimp expression temperature of the latent crimped fiber to prepare a mixture,
(B) forming a sheet-like web from the mixture,
(C) The sheath of the fibrous binder is melted by heating the web, and the entanglement point with the elastic fiber, the entanglement point with the latent crimped fiber, or the elastic fiber and the latent crimped fiber After joining the confounding points,
(D) A method for producing a stretchable nonwoven fabric, wherein the crimp of the latent crimped fiber is expressed by heating the web. The method for producing a stretchable nonwoven fabric according to claim 7, wherein in the step (a), water is used as a dispersion medium for dispersing the elastic fibers, the crimped fibers, and the fibrous binder.

Images