KR20080088571A - Nonwoven fabric, articles including nonwoven fabrics, and methods of making nonwoven fabrics - Google Patents

Abstract

Briefly described, embodiments of this disclosure include nonwoven fabrics, methods of making nonwoven fabrics, articles including nonwoven fabric, and the like.

Description

Nonwoven Fabrics, Articles including Nonwoven Fabrics, and Methods of Making Nonwoven Fabrics

The present invention relates to general nonwoven fabrics and nonwoven fabrics that exhibit higher bulk properties.

The need for nonwoven fabrics for use in applications related to hygiene, medical fabrics, wipes, and the like continues to increase. In addition, practicality, economics and aesthetics often have to be satisfied at the same time. The market for polyolefin fabrics and articles made from polyolefins with enhanced properties and improved softness and bulk continues to expand.

The production of polymeric fibers as nonwoven materials generally requires the use of a mixture of at least one polymer with a small amount of additives such as stabilizers, pigments, antacids and the like. The mixture is melt molded and processed into fibers and fiber products using conventional commercial processes. Nonwoven fabrics can be made by making a web and then bonding the fibers together by heat. For example, staple fibers can be converted to a nonwoven fabric using, for example, a carding machine, and the carded fibers are joined by heat. Such thermal bonding can be accomplished by a variety of heating techniques, including heated rollers, heating with hot air, and heating via ultrasonic welding.

In addition, the fibers can be made and consolidated into nonwovens by various other methods. For example, fibers and nonwovens can be made by a spunbonding process, a meltblowing process, or a combination of the above methods. In addition, the strengthening process may include needlepunching, through-air thermal bonding, ultrasonic welding and hydroentangling.

Many nonwoven fabrics, such as conventional thermally bonded nonwoven fabrics, do not exhibit sufficient bulk or extensibility for any purpose use. Therefore, there is a need for nonwoven fabrics that exhibit sufficient bulk and extensibility.

Embodiments disclosed herein will use textile techniques, chemical reactions, and the like, in the art, unless otherwise noted. Such techniques are explained fully in the literature.

The following examples are provided to provide those of ordinary skill in the art with a complete disclosure and description of how to perform the methods disclosed and claimed herein and how to use the compositions and compounds disclosed and claimed herein. Presented. Efforts have been made to ensure accuracy with respect to numbers (eg amounts, temperature, etc.) but some errors or deviations can be expected. Unless indicated otherwise, the ratio is percentage by weight, temperature is in degrees Centigrade, and pressure is at or near atmospheric. The reference temperature and pressure are defined as 25 ° C. and 1 atmosphere.

Before describing in detail the embodiments disclosed in the present invention, it should be understood that the disclosure of the present invention may vary, without being limited to particular materials, reagents, reactants, manufacturing processes or the like, unless otherwise indicated. . Also, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. It is also possible for the steps disclosed in the present invention to be performed in a different order where logically possible.

It is to be understood that the singular forms "a" and "an" and "the" as used in the specification and the appended claims include plural objects unless the context clearly dictates otherwise. That is, for example, one support or "a support" refers to a plurality of "supports". In this specification and in the claims that follow, reference will be made to a number of terms that are defined to have the following meanings unless the intention is otherwise clear.

It should be appreciated that ratios, concentrations, amounts and other numerical data may be presented in a range format herein. These range formats are used for convenience and brevity, and therefore, not only are the numbers explicitly stated as a limitation of the range, but also as each individual number and sub-range are explicitly stated, every individual contained within that range. It should be understood that they should be interpreted in a flexible manner to include numerical or sub-ranges. As an example, the concentration range of about 0.1% to 5% may be defined in the range of about 0.1 wt% to about 5 wt%, as well as the individual concentrations within the indicated range (eg, 1%, 2%, 3% and 4%) and sub-ranges (eg 0.5%, 1.1%, 2.2%, 3.3% and 4.4%) should also be construed as including.

Justice

In describing and claiming the subject matter disclosed in the present invention, the following terminology will be used in accordance with the definitions shown below.

As used herein, the term "nonwoven" fabric, sheet, or web is oriented or randomly oriented, as opposed to a regular pattern of mechanically inter-engaged fibers, and frictional forces. Means the textile structure of each fiber, filament or yarn that interacts with each other by, and / or by bonding and / or cohesion (e.g., this is not a woven or knitted fabric). Examples of nonwoven fabrics and webs include carded webs, spunbond continuous filament webs, meltblown webs, air-laid webs and wet-ray webs. (wet-laid webs), including but not limited to. Suitable bonding methods include thermal bonding, chemical or solvent bonding, resin bonding, mechanical needling, hydraulic needling, stitch-bonding, combinations of the above methods, and the like. Illustrative and non-limiting embodiments disclosed herein include carded thermal bond nonwoven fabrics.

The term "bonding" is used herein to describe the areas of nonwoven fabrics that have bonding or entanglement between fibers beyond those occurring in nonwoven fabrics.

The term "bulk" or "loft" is used as indicating the bulk specific volume of the nonwoven for a given area density. In general, "bulk" and "loft" are used interchangeably. Thus, "bulk" is used to describe both "bulk" and "loft". The expansion specific volume can be obtained by dividing the bulk volume of the nonwoven sample by its mass. Bulky nonwovens are relatively less dense than compressed ones. Area density is the mass per unit area and is usually reported in g / square meters (gsm). Area density often appears as a basis weight and these terms are equivalent.

"Shrinkage" as used to refer to fibers refers to a reduction in fiber length as measured by thermomechanical analysis (TMA). A typical instrument for measuring shrinkage is the Model Q 400 manufactured by TA Instruments. A discussion of shrinkage can be found on pages 736-743 of "Thermal Characterization of Polymeric Materials", Academic Press (1981), incorporated herein by reference. 1A and 1B show graphs of shrink and non-shrink fibers.

The term "extensibility" as used to refer to nonwoven fabrics refers to the ability of the fabric to stretch significantly upon application of stress.

The term "elasticity" refers to the ability of a stretchable nonwoven to revert to a pre-stressed state essentially upon release of stress.

The term "activation" refers to the process used to increase the bulk after the formation of a nonwoven fabric.

General discussion

Embodiments disclosed herein are briefly summarized as including nonwoven fabrics, methods of making nonwoven fabrics, products including nonwoven fabrics, and the like. Nonwoven fabrics in the present invention have improved effects compared to other nonwoven fabrics (eg, increased bulk, tactile texture, improved foreign particle removal, increased area density, etc.).

In addition, the nonwoven fabrics in the present invention are highly stretchable compared to other nonwoven fabrics. The degree of extensibility depends on the activation temperature, fabric structure, bonding pattern and the like. Under certain conditions, there may be alternating degrees of alternation depending on activation temperature, fabric structure, bonding pattern, and the like.

Nonwoven fabrics may be included in such products as, but not limited to, cleaning wipes, diapers, textile stretch components, incontinence care products, women's care products, filters and felts, and the like. Nonwoven fabrics can be used in products such as landing zones, acquisition / distribution layers, stretch ears, top sheets, back sheets, and the like.

By selecting components of the nonwoven fabric (eg, fibers), parameters for handling the nonwoven fabric, bonding patterns, and the like, the nonwoven fabric can be made to have a predetermined bulk, constant softness / roughness, area density, and the like. In other words, the nonwoven fabric may be one that cleans a surface (eg, a smooth or rough surface); Collecting, distributing or conveying liquids; Adding stabilizers filtered by liquid, gas or powder; Acoustic attenuation; It may be designed for use in many applications, such as and / or combinations thereof, but is not limited to such applications.

In general, nonwoven fabrics include one or more nonwoven layers comprising at least a first fiber and a second fiber. The first and second fibers have different shrinkage levels or shrinkage ratios under certain conditions (eg, activation temperature and time for shrinking the fiber and degree of restraint on dimensional change). Upon activation, the second fiber shrinks, and as the second fiber shrinks in size, the second fiber pulls some of the first fibers together to create one or more increased bulk regions.

Such nonwoven fabrics may have an bulk increase of about 20 to 500%, about 30 to 450% and about 50 to 350% relative to the bulk of the inert nonwoven fabric. Such nonwoven fabrics may increase in thickness by about 30-650%, about 45-550% and 60-500% compared to the thickness of the inert nonwoven fabric.

The activation conditions applied to the nonwoven fabrics (e.g., the degree of restraint to temperature and time or size variations) may, at least in part, include the fiber composition, the desired shrinkage, the feel of the desired nonwoven fabric tissue (e.g. soft to coarse), It depends on the desired amount of bulkiness, the level of extensibility and elasticity desired. Activation of the fibers in the nonwoven fabric is generally performed while the fibers are in a loose state (eg, when there is little or no tension in the machine direction or in a direction that intersects the forces generated by the shrink fibers). In yet another embodiment, such as but not limited to tenter frame process, sanforizing process, creping process, allied process and combinations of the above processes By using a controlled size change process, the shrinkage can be adjusted in the machine direction and / or in the cross direction. The activation conditions, fiber type, number of nonwoven layers in the nonwoven fabric, and the like are selected to achieve the desired effect (e.g., bulk, texture feel, and combinations thereof). Shrinkage can also be controlled in the machine direction and / or cross direction by adjusting the ratio of the number of fibers oriented in the machine direction to the number of fibers oriented in the cross direction.

In general, the activation temperature of the second fiber (eg of an oven or other heat source) is below the melting point of the polymer. Therefore, the activation condition depends at least in part on the type of polymer fiber used as the second fiber. For example, when the second fiber is polypropylene, the activation temperature is about 125 ° C. to 150 ° C. for a time of about 10 seconds to 1 minute. The activation temperature may be obtained by processes such as heated gas, infrared heating source, oven, and the like, but is not limited thereto. One skilled in the art can alter one or both of the temperature and time conditions to achieve the desired result.

In another embodiment, the nonwoven fabric includes a pattern of differentiated shrink domains. The differentiated contraction domain is defined by the binding pattern (described below) of the first domain and the second domain. The first shrink domain is defined as the area of the nonwoven fabric to which it is bonded (eg, some of the first and second fibers are bonded to each other). On the other hand, the second shrinkage domain is defined as the area of the unbonded nonwoven fabric. Contraction of the first contraction domain under activation conditions is very small compared to contraction of the second contraction domain under activation conditions.

The first and second fibers may be included in both the first and second shrink domains and some of the fibers may be in both domains. As mentioned above, the first and second fibers have different shrinkage rates under certain conditions (eg, activation temperature and time to shrink the fibers). Exposing the nonwoven fabric to activation conditions causes the length of the second fiber to shrink. As the second fiber shrinks, the second fiber also draws the first fiber together. This shrinkage of the second fiber causes the first fiber to collect in the region of the second domain, which can increase the bulk of the nonwoven fabric. The bulk increase is increased when the nonwoven fabric is patterned so that the bonded area prevents loosening of the first and second fibers.

In an exemplary embodiment, the nonwoven fabric includes a single nonwoven layer comprising a mixture of first and second fibers. The nonwoven fabric has a pattern of differentiated shrinkage domains caused by joining the first domain (first binding domain) of the nonwoven fabric and leaving other unbound portions (second binding domain). In one embodiment, the first fiber is a non-shrink fiber (defined below) and the second fiber is a shrink fiber. Non-shrink and shrink fibers have different shrink rates under certain activation conditions. Nonwoven fabrics are exposed to activation conditions that cause the shrink fibers to shrink, while the non-shrink fibers do not substantially shrink (as described below). Shrink fibers cause non-shrink fibers to collect in the second domain, increasing the bulk of the nonwoven fabric.

In another exemplary embodiment, the nonwoven fabric includes a first nonwoven layer comprising a first fiber, a second nonwoven layer comprising a second fiber, and a third nonwoven layer comprising the first fiber. The nonwoven fabric is caused by bonding the first domain of the nonwoven fabric (eg, combining the first, second, and third nonwoven layers) and leaving other portions that are not bonded (the second binding domain). Has a pattern of differentiated contraction domains. In one embodiment, the first fiber is a non-shrink fiber (defined below) and the second fiber is a shrink fiber. Non-shrink and shrink fibers differ in the degree of shrinkage under certain activation conditions. Nonwoven fabrics are exposed to activating conditions that cause the shrink fibers to shrink, while the non-shrink fibers do not substantially shrink (as described below). Shrink fibers in the second nonwoven layer allow non-shrink fibers in the first and third nonwoven layers to collect in the second domain and increase the bulk of the nonwoven fabric.

Nonwoven fabric

As mentioned above, nonwoven fabrics include, but are not limited to, at least a first fiber and a second fiber. In one embodiment, the nonwoven fabric comprises a first fiber, a second fiber and a third fiber. Other embodiments may include four or more fibers (eg, first fiber, second fiber, and nth fiber). Details of the fibers are described herein.

The nonwoven fabric can include one or more nonwoven layers (eg, a first nonwoven layer, a second nonwoven layer, and an nth nonwoven layer). Embodiments disclosed herein may include nonwoven fabrics having one, two, three, four, five, six, seven, eight, nine, ten or more nonwoven layers. Each nonwoven layer may include, but is not limited to, additional fibers as well as first and / or second fibers. In an embodiment the nonwoven layer intersects the nonwoven layer comprising the first fiber and the nonwoven layer comprising the second fiber. In an embodiment the nonwoven layer intersects a nonwoven layer comprising non-shrinkable fibers and a nonwoven layer comprising shrinkable fibers. Exemplary embodiments of nonwoven fabrics are described herein. On the other hand, other embodiments that include at least a first fiber and a second fiber that differ in shrinkage level or speed are also included within the scope of the present disclosure.

In one embodiment, the nonwoven fabric comprises one nonwoven layer. The nonwoven layer includes at least a first fiber and a second fiber. In yet another embodiment, the nonwoven layer includes a first fiber, a second fiber and one or more additional fibers.

In an embodiment, the nonwoven fabric includes a first nonwoven layer and a second nonwoven layer. The first nonwoven layer is arranged over the second nonwoven layer. In one embodiment, the first nonwoven layer is made of first fibers and the second nonwoven layer is made of second fibers. In another embodiment, the first nonwoven layer is made of a first fiber and a second fiber and the second nonwoven layer is made of a first fiber, a second fiber, a third fiber, or any combination of the above fibers.

In an embodiment, the nonwoven fabric comprises a first nonwoven layer, a second nonwoven layer and a third nonwoven layer. In one embodiment, the first nonwoven layer and the third nonwoven layer are made of first fibers, while the second nonwoven layer is made of second fibers. In another embodiment, the first nonwoven layer is made of a first fiber, the second nonwoven layer is made of a second fiber, and the third nonwoven layer is made of a third fiber. In yet another embodiment, the nonwoven layer described in the previous embodiments can include any of the first fiber, second fiber, third fiber and / or a combination of one or more other fibers.

In each embodiment of the nonwoven fabric, the type of fiber and the bond of the fibers (eg, in the same or different layers) may depend upon the particular properties required by the particular nonwoven fabric (eg, the bulk of the nonwoven fabric, one of the nonwoven fabrics, or More tissues, etc.). It should be noted that not only the pattern of differentiated shrink domains but also the conditions under which the nonwoven fabric is bound and activated can be used to match the properties of the nonwoven fabric.

Nonwoven fabrics may be formed using one or more processes. Nonwoven fabrics include carded thermal bonds, carded spun laces, carded through-air bonds, wet laying, carded needlepunches, spuns Can be formed using processes such as, but not limited to, spun bonds, air laying, melt blowing and combinations thereof, each of which is typically used in the art. It is meant to be found in the above processes. In one embodiment, the nonwoven fabric is formed using a card thermal bonding process. Additional details regarding embodiments of nonwoven fabrics are described in the Examples.

sters GmbH & Co. KG(독일) 등과 같은 부직포 롤 제조회사에 의해 제공될 수 있는 패턴)을 사용하여 만들어질 수 있고 또는 다른 패턴들의 사용에 의해서도 만들어질 수 있다. 패턴은, 롤 패턴(patterned rolls)을 이용한 캘렌더 결합(calendar bonding), 수소융착(hydroentangling) 내 패터닝 젯(patterning jets), 패턴 니들펀칭(patterned needlepunching) 등과 같은 공정 그리고 이들의 조합을 이용하여 만들어질 수 있다.As mentioned above, the nonwoven fabric has a pattern of differentiated shrinkage domains. Patterns of differentiated contraction domains are known patterns (e.g. Andritz K

sters GmbH & Co. Patterns, which can be provided by nonwoven roll manufacturers such as KG (Germany) or the like, or can also be made by the use of other patterns. Patterns are made using processes such as calendar bonding using patterned rolls, patterning jets in hydroentangling, patterned needlepunching, and combinations thereof. Can lose.

After the fibers of the nonwoven fabric have been treated with activation conditions to form bulk, the nonwoven fabric can be post-treated. Post-treatment includes, but is not limited to, corona, plasma, oil release, flame retardants, antibacterial agents, softeners, and the like and combinations of the foregoing.

fiber

The first fibers may include, but are not limited to, natural or naturally derived fibers (hereinafter referred to as "natural fibers"), thermoplastic polymeric fibers, and thermosetting resins and high performance polymeric fibers. The second fiber may include, but is not limited to, polymeric fibers (eg, thermoplastic polymer fibers). Additional fibers (eg, third fibers, etc.) may include, but are not limited to, natural fibers, polymeric fibers, and thermosetting resins and high performance fibers. The first and second fibers are polymeric blend fibers, bi-component fibers (e.g., fibers comprising two different polymers of different chemical composition / properties) and bi-constituent fibers. (Eg, a fiber composed of two or more other fibers joined prior to the extrusion process), but is not limited thereto. The first fiber and the second fiber can be made by the same process or by different processes.

Natural fibers can include, but are not limited to, plant fibers, vegetable fibers, and animal / insect fibers. Natural fibers are derived from animal skins, cocoon fibers, and plant seeds, leaves, and stem fibers. Typical examples of natural fibers include, but are not limited to, wool, cotton, silk, linen, ramie, hemp, jute. In an embodiment, natural fibers include, but are not limited to, rayon, lyocell, polylactic acid, soy protein, and combinations thereof.

The thermosetting resin and the high performance polymer may include, but are not limited to, carbon fibers, glass fibers, polyacrylonitrile fibers, polyvinyl alcohol fibers, polyaramid fibers, combinations thereof, and the like.

Polymerized fibers and thermoplastic polymeric fibers can be made of copolymers, trimers and higher higher polymers. It should be noted that the term "copolymer" includes two or more monomers within the same polymer chain. The polymeric fibers and thermoplastic polymeric fibers can be mono-component or multi-component. The polymeric fibers and the thermoplastic polymeric fibers may be polymer blends.

Polymerized fibers and thermoplastic polymer fibers include, but are not limited to, polyolefins, polyesters, polypropylenes, polyethylenes, polybutenes, polymethylpentenes, ethylene-propylenes, polyamides, polyurethanes, polyvinylacetates, ethylene vinyl acetates, polys Thermoplastic polymers such as respective polymer blends or copolymers of etheresters, polyetherurethanes, and combinations thereof.

Various aspects disclosed in the present invention can be better understood with reference to the following figures. The components in the figures are not necessarily the exact size in relation to other portions, but are highlighted to clearly illustrate the principles disclosed in the present invention. In addition, like reference numerals in the drawings indicate corresponding parts through several gazes.

1A and 1B show graphs of shrink fibers (FIG. 1A) and non-shrink fibers (FIG. 1B).

2A and 2B show optical micrographs of cross-sectional views of the nonwoven web disclosed in the present invention. 2A shows one embodiment of a nonwoven web used to produce a thick nonwoven fabric that is not activated by a thermal bulk step. 2B shows the nonwoven web activated to produce a thick nonwoven web.

Figure 3 illustrates a number of embodiments of the nonwoven fabric disclosed herein.

In embodiments, the polymeric fibers and the thermoplastic polymeric fibers include, but are not limited to, each polymer blend of polyolefins, polyesters, polyamides, polyvinylacetates, polyacrylonitriles, polyvinyl alcohols and ethyleneacrylic acids and combinations thereof. Or made of a material such as a copolymer.

In an embodiment, the polymeric fibers and thermoplastic polymeric fibers may comprise spinable polymeric materials, such as blends comprising polyolefins and polyolefins (eg, US Pat. Nos. 5,733,646, 5,888,438, 5,431,994). , 5,318,735, 5,281,378, 5,882,562 and 5,985,193, the disclosure of which is incorporated herein by reference in its entirety.)

In an embodiment, the polymer is polypropylene or a blend comprising polypropylene. The polypropylene may comprise polypropylene which can be spun. The polypropylene may be atactic, heterotactic, syndiotactic, isotactic and stereoblock polypropylene, including partially and fully isotactic or at least substantially completely isotactic polypropylene.

The term polymer (e.g., polyolefin, polypropylene, polyethylene, etc.) refers to homopolymers and heteropolymers (e.g. copolymers and terpolymers) and mixtures thereof (blends and independent batches in situ). And alloys produced by mixing or forming blends. For example, the polymer can include copolymers of olefins such as propylene and these copolymers can include various components.

As used herein, polypropylene is used in the common commercial sense that polypropylene is a substantially linear molecule. In addition, as used herein, the polypropylene component includes a material containing a wide range of molecular weight linear polypropylenes so as to obtain filaments and fibers having excellent spinning and thermal bonding properties.

Conventional polymeric fibers include polypropylene staple fibers. Such fibers also include bi-component fibers containing various combinations of polypropylene or combinations of other polymeric materials such as polyethylene. Particularly used polymeric fibers that are commonly used to make nonwoven webs or fabrics are high thermal bond strength spun melt fibers described in US Pat. No. 5,281,378, which is incorporated herein by reference in its entirety.

In an embodiment, the polypropylene has an average molecular weight of about 3x105 to about 5x105, a melt flow rate (MFR) of about 7 to about 50 dg / min (ASTM D-1238-86, incorporated herein by reference in its entirety). Condition L; 230 / 2.16) and / or spin temperatures in the range of about 220 to 315 ° C, about 240 to 300 ° C and about 255 to 285 ° C.

In an embodiment, the polypropylene may be linear or branched, as disclosed in US Pat. No. 4,626,467, which is incorporated herein by reference in its entirety, but is preferably linear. In addition, the polypropylenes to be made of fibers may include polypropylene components, such as those disclosed in U.S. Pat. have. In addition, polymer blends such as those disclosed in US Pat. No. 5,882,562 and EP 0 719 879, which are incorporated herein by reference in their entirety, may also be used. The first and second fibers may have the same or different size and / or cross section and may have deniers of about 0.1-50 denier per filament. In addition, the first and second fibers may be staple fibers or continuous fibers having a length of about 1 mm to 250 mm.

Melt flow rate (MFR) depends on the type of polymer making the fiber and, therefore, the MFR may vary depending on which fiber is selected for each particular application. In an embodiment, the first polyolefin fiber and the second polyolefin fiber are determined by a melt flow rate of about 10-400 dg / min (ASTM D-1238-86 (condition L; 230 / 2.16), incorporated herein by reference in its entirety) ), But such MFR depends on the chemical composition of the fiber.

In an embodiment, the first fiber has a first fiber shrinkage (measured using TMA) and the second fiber has a second fiber shrinkage. Wherein the difference between the first and second fiber shrinkage is at least about 8%, at least about 9%, at least about 10%, at least about 12% or at least about 15%. It should be noted that in the examples the length of the first fiber may increase and not shrink.

In an embodiment, the first fiber has a first fiber shrinkage of less than about 10%, less than about 8%, less than about 6%, less than about 3%, or less than about 1%, each of the same conditions (Eg, temperature near the activation temperature of the fibers of interest) and may be referred to as "non-shrink fibers".

Non-shrink fibers can include, but are not limited to, polypropylene, polyester, and combinations thereof. In embodiments where the non-shrink fibers are made of polypropylene, the fiber shrinkage is less than about 10% at about 140 ° C. It should be noted that in the examples the length of the non-constricted fibers may increase and not shrink.

The second fiber has a fiber shrinkage of greater than about 9%, greater than about 10%, greater than about 11%, greater than about 12%, greater than about 13%, and may be referred to as a "shrinkage fiber".

Shrink fibers may include, but are not limited to, polypropylene, polyester, polyethylene, and bicomponent fibers made therefrom. In embodiments where the shrink fibers are made of polypropylene, the fiber shrinkage is about 9-40% at about 140 ° C.

The production of polymeric fibers for nonwoven materials may include the use of mixtures of at least one polymer with very small amounts of additives, such as, but not limited to, antioxidants, stabilizers, pigments, antacids, reinforcing agents, and the like. . Therefore, the polymer or polymer blend may include various additives such as, but not limited to, melt stabilizers, antioxidants, pigments, antacids, antistatic agents, emulsifiers, preservatives and reinforcing agents, and the like. The type, nature and amount of additives can be determined by one of ordinary skill in the art taking into account the requirements of the product.

Various finishes may be applied to the fibers to keep the fibers hydrophilic or hydrophobic or to make them hydrophilic or hydrophobic. Finish components, including hydrophilic finish or hydrophobic finish, may be selected by those skilled in the art depending on the characteristics of the device and the needs of the product to be produced.

In addition, one or more components may be included in the polymer blend to alter the surface properties of the fiber for the purpose of providing repeat wetting to the fiber or preventing or reducing the build up of static electricity. The hydrophobic finish composition preferably comprises an antistatic agent. Hydrophilic finishes may also include such antistatic agents.

Additional details regarding embodiments of nonwoven fabrics are described in the Examples.

Example

The embodiments disclosed herein have now been described, and in general, the examples describe some additional embodiments disclosed herein. The embodiments disclosed in the present invention have been described in connection with the examples and corresponding texts and drawings, but the description is not intended to limit the embodiments disclosed in the present invention. On the contrary, the intention is to cover all alternatives, modifications, and equivalents falling within the meaning and scope of the embodiments disclosed in the present invention.

Some examples of nonwoven fabrics A-G having a combination of fibers NS1, NS2, NS3, NS4, NS5, S1 and S2 shown in FIG. 3 are shown. Examples provide many examples depending on the range of fabric weight, structure, fiber component, fiber type, number of nonwoven layers, fabric formation method, and the like.

2A and 2B show photomicrographs of the cross-sectional view of nonwoven fabric A of FIG. 3. 2A shows an embodiment of a nonwoven fabric used to make a thick nonwoven fabric that is not activated by a thermal bulking step. 2B shows a nonwoven web activated to produce a thick nonwoven web.

It should be emphasized that the above embodiments disclosed in the present invention are merely viable examples, and are shown only for a clear understanding of the principles of the invention disclosed herein. Many variations and modifications may be made to the above embodiments without departing substantially from the spirit and principles of the invention. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims.

Claims (19)

A fabric comprising a nonwoven fabric having at least a first fiber and a second fiber, the fabric comprising: The first fiber has a first fiber shrinkage rate, the second fiber has a second fiber shrinkage rate, And the difference between the first fiber shrinkage rate and the second fiber shrinkage rate is at least about 8%. The method of claim 1, The nonwoven fabric comprises at least a first shrink domain and a second shrink domain, And the first and second shrink domains define a differentiated shrink domain. The method of claim 1, And the difference between the first fiber shrinkage rate and the second fiber shrinkage rate is at least about 10%. The method of claim 1, And the first fiber is a non-shrink fiber having a first fiber shrinkage of less than about 5%. The method of claim 1, And the first fiber is a non-shrink fiber having a first fiber shrinkage of less than about 3%. The method of claim 1, The first fiber is a thermoplastic polymer fiber made of a polymer, The polymer may be a polyolefin, polyester, polypropylene, polyethylene, polybutene, polymethylpentene, ethylene-propylene, polyamide, polyurethane, polyvinylacetate, ethylenevinylacetate, polyetherester, polyetherurethane and combinations thereof Selected from each of the polymer blends or copolymers, The second fiber is polyolefin, polyester, polypropylene, polyethylene, polybutene, polymethylpentene, ethylene-propylene, polyamide, polyurethane, polyvinylacetate, ethylenevinylacetate, polyetherester, polyetherurethane and A fabric characterized in that the thermoplastic fiber is selected from the respective polymer blends or copolymers of the bath. The method of claim 1, The first fiber is a natural fiber made of a material selected from wool, cotton, silk, linen, ramie, hemp, jute and combinations thereof, The second fiber is polyolefin, polyester, polypropylene, polyethylene, polybutene, polymethylpentene, ethylene-propylene, polyamide, polyurethane, polyvinylacetate, ethylenevinylacetate, polyetherester, polyetherurethane and A fabric characterized in that it is a polymeric fiber selected from each of the polymer blends or copolymers of the combination. The method of claim 1, The first fiber is a fiber obtained from a natural material, The natural material is selected from rayon, lyocells, polylactic acid, soy protein and combinations thereof, The second fiber is polyolefin, polyester, polypropylene, polyethylene, polybutene, polymethylpentene, ethylene-propylene, polyamide, polyurethane, polyvinylacetate, ethylenevinylacetate, polyetherester, polyetherurethane and A fabric characterized in that it is a polymeric fiber selected from each of the polymer blends or copolymers thereof. The method of claim 1, The first fiber is selected from carbon fiber, glass fiber, polyacrylonitrile fiber, polyvinyl alcohol fiber, polyaramid fiber, combinations thereof, The second fiber is polyolefin, polyester, polypropylene, polyethylene, polybutene, polymethylpentene, ethylene-propylene, polyamide, polyurethane, polyvinylacetate, ethylenevinylacetate, polyetherester, polyetherurethane and A fabric characterized in that it is a polymeric fiber selected from each of the polymer blends or copolymers of the combination. The method of claim 1, Wherein the nonwoven fabric comprises at least a first nonwoven layer, And the first and second fibers are included in the first nonwoven layer. The method of claim 1, Wherein the nonwoven fabric comprises a third fiber having a third fiber shrinkage, The difference between the third fiber shrinkage rate and the second fiber shrinkage rate is at least about 8%, The nonwoven fabric comprises at least a first nonwoven layer, And the first fiber, the second fiber and the third fiber are included in the first nonwoven layer. The method of claim 1, Wherein the nonwoven fabric comprises at least two nonwoven layers, The first nonwoven layer is arranged over the second nonwoven layer, And the first fiber is in the first nonwoven layer and the second fiber is in the second nonwoven layer. The method of claim 1, Wherein the nonwoven fabric comprises at least three nonwoven layers, A first nonwoven layer is arranged over the second nonwoven layer, a third nonwoven layer is arranged over the second nonwoven layer on the opposite side of the first nonwoven layer, And the first fiber is in the first nonwoven layer and the third nonwoven layer and the second fiber is in the second nonwoven layer. The method of claim 1, And the first and second fibers are each selected from polymer blend fibers, bi-component fibers, bi-component fibers and combinations thereof. An article comprising a nonwoven fabric having at least a first fiber and a second fiber, the article comprising: The first fiber has a first fiber shrinkage rate and the second fiber has a second fiber shrinkage rate, the difference between the first fiber shrinkage rate and the second fiber shrinkage rate is at least about 8%, the product comprises a cleaning wipe, An article characterized in that it is selected from diapers, textile stretch components, incontinence care products, women's care products, felts and filters. A fabric comprising a nonwoven fabric having at least a first shrink domain and a second shrink domain, The first contraction domain and the second contraction domain define a differentiated contraction domain, And the nonwoven fabric comprises at least a first fiber and a first shrink fiber. The method of claim 16, The first fiber is a first polypropylene fiber and the first shrink fiber is a second polypropylene fiber, And the first polypropylene fiber and the second polypropylene fiber have a shrinkage difference of at least about 8%. Providing a nonwoven fabric having a difference between a first fiber shrinkage rate and a second fiber shrinkage rate of at least about 8%, the first fiber having the first fiber shrinkage rate and the second fiber having the second fiber shrinkage rate; The first contraction domain and the second contraction domain define a differentiated contraction domain, wherein at least the first contraction domain and the portion of the first fiber and a portion of the second fiber are joined in the first contraction domain; Forming a second contraction domain; And Heating the nonwoven fabric to an activation temperature of the second fiber, causing the second fiber to shrink and cause the first fiber to gather to increase the thickness of the nonwoven fabric in the second shrinkage domain. Method of forming a nonwoven fabric comprising a. Providing a nonwoven fabric having a difference between a first fiber shrinkage rate and a second fiber shrinkage rate of at least about 8%, the first fiber having the first fiber shrinkage rate and the second fiber having the second fiber shrinkage rate; And Heating the nonwoven fabric to an activation temperature of the second fiber, causing the second fiber to shrink and cause the first fiber to gather to increase the thickness of the nonwoven fabric. Method of forming a nonwoven fabric comprising a.

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