Substrates and laminates for absorbent articles
阅读说明:本技术 用于吸收制品的基底和层合体 (Substrates and laminates for absorbent articles ) 是由 K.A.阿罗拉 J.L.哈蒙斯 D.R.希尔 于 2019-02-14 设计创作,主要内容包括:本公开提供了用于吸收制品的基底和层合体(200)以及包括所述基底或层合体的吸收制品。基底和层合体可具有三维元件(208)、着陆区域(210)、和位于着陆区域中的至少一些与三维元件中的至少一些中间的渗透性增加的区域(212)。渗透性增加的区域可邻近三维元件定位。着陆区域可具有第一基重,所述第一基重大于渗透性增加的区域的第二基重。(The present disclosure provides substrates and laminates (200) for absorbent articles and absorbent articles comprising the substrates or laminates. The substrate and laminate may have three-dimensional elements (208), land areas (210), and regions of increased permeability (212) located intermediate at least some of the land areas and at least some of the three-dimensional elements. The region of increased permeability may be located adjacent to the three-dimensional element. The land areas may have a first basis weight that is greater than a second basis weight of the areas of increased permeability.)
1. A substrate for an absorbent article, the substrate comprising:
a nonwoven material, the nonwoven material comprising:
fibers;
a three-dimensional element;
a landing area comprising the fibers and positioned in an area free of the three-dimensional elements;
wherein, in the landing zone, the nonwoven material has a first basis weight according to the micro-CT test;
an area of increased permeability comprising the fibers and positioned adjacent to and intermediate at least some of the three-dimensional elements and at least some of the land areas; and is
Wherein in the areas of increased permeability, the nonwoven material has a second basis weight in a range of less than 75% to less than 25% of the first basis weight of the landing areas according to the micro-CT test.
2. The substrate of claim 1 wherein the nonwoven material comprises through-air bonds between at least some of the fibers.
3. The substrate of claim 1 or 2, wherein the nonwoven material comprises a through-air-bonded material.
4. The substrate of any one of the preceding claims, wherein the nonwoven material comprises bonds joining at least some of the fibers, the bonds each having a bond strength, the fibers each having a fiber break strength, wherein the sum of the bond strengths in an area of the nonwoven material is less than the sum of the fiber break strengths in the area of the nonwoven material.
5. The substrate of claim 4 wherein the area of the nonwoven material at least partially overlaps the area of increased permeability.
6. The substrate of any preceding claim, wherein in the three-dimensional element the nonwoven material has a third basis weight, and wherein the third basis weight is substantially the same as the first basis weight of the landing area according to the micro-CT test.
7. The substrate of any one of the preceding claims, wherein the nonwoven material is hydrophobic.
8. The substrate of any one of claims 1 to 6, wherein the nonwoven material is hydrophilic.
9. The substrate of any one of the preceding claims, wherein the fibers comprise carded fibers.
10. The substrate of any one of claims 1 to 8, wherein the fibers comprise continuous fibers.
11. The substrate of any one of the preceding claims, wherein the areas of increased permeability have a second basis weight ranging from less than 60% to less than 35% of the first basis weight of the land areas according to the micro-CT test.
12. The substrate of any one of the preceding claims, wherein the fibers have a substantially constant fiber diameter in the three-dimensional element according to the fiber diameter and denier test.
13. The substrate of any preceding claim, wherein the fibers comprise bicomponent fibers.
14. An absorbent article comprising:
the substrate of any one of the preceding claims;
a liquid impervious backsheet;
an absorbent core disposed at least partially intermediate the substrate and the liquid impervious backsheet.
15. A laminate, comprising:
the substrate of any one of claims 1 to 13 wherein the nonwoven material is a first nonwoven material, the laminate comprises a second nonwoven material, wherein the first nonwoven material extends into or through the second nonwoven material to form the three-dimensional element and form the laminate of the first nonwoven material and the second nonwoven material, the laminate comprises land areas located in areas of the first nonwoven material and the second nonwoven material that are free of the three-dimensional element, wherein the land areas in the laminate have a third basis weight.
Technical Field
The present disclosure relates generally to substrates and laminates for absorbent articles, and more particularly to substrates and laminates for absorbent articles that include regions of increased permeability.
Background
Absorbent articles are used to contain and absorb body exudates (i.e., urine, bowel movement products, and menses). The absorbent article may take the form of, for example, a diaper, a sanitary pant, an adult incontinence garment, a sanitary napkin, and/or a tampon. These absorbent articles typically comprise a liquid pervious topsheet, a liquid impervious backsheet, and an absorbent core positioned at least partially intermediate the topsheet and the backsheet. The absorbent article also includes an acquisition layer or secondary topsheet positioned at least partially intermediate the topsheet and the absorbent core. In recent years, consumers have shown a desire for topsheet substrates and/or topsheet laminates, topsheet/acquisition layer laminates, or topsheet/secondary topsheet laminates having three-dimensional elements. The substrates and/or laminates, due to their three-dimensional configuration and relatively high basis weight, may occasionally hinder the absorbency of body exudates and have a wet feel during use. Accordingly, these substrates and/or laminates should be improved to better wick bodily exudates through the substrate and/or laminate.
Disclosure of Invention
The present disclosure provides improved substrates and/or laminates for absorbent articles and absorbent articles including the improved substrates and/or laminates. The substrate and/or laminate may include three-dimensional elements having improved texture definition and/or more fibers in the three-dimensional elements due at least in part to less fiber breakage. The substrate and/or laminate may have better bodily exudate acquisition due to the regions of increased permeability in the substrate and/or laminate. The substrates and/or laminates may also have a better balance of dryness and bodily exudate acquisition than previous substrates and/or laminates. In the case of a hydrophobic layer facing the wearer, rapid acquisition of body exudates is even more important. The substrate and/or laminate may be bonded with at least one layer of through-air bonded nonwoven or lightly bonded (e.g., the bonds can at least partially break upon application of force, such as when creating a three-dimensional element, or the fibers can move relative to the bonds) nonwoven. Through air bonded or lightly bonded nonwoven materials may include, for example, carded fibrous nonwoven materials or continuous fiber nonwoven materials. Through-air bonded or lightly bonded nonwoven materials can allow the fibers to move during the formation of the three-dimensional element, thereby reducing fiber breakage and creating areas of improved permeability adjacent the three-dimensional element. The lightly bonded material may have calender bonds or spot bonds that cause the fibers to move out of or relative to the calender bonds or spot bonds when one or more forces are applied to a portion of the fibers, such as during three-dimensional element formation. Thus, lightly bonded calender bonds or point bonds may allow the fibers to move without causing attenuation or breakage of the fibers or with a small amount of attenuation or breakage of the fibers. Through-air bonded nonwovens typically have fiber-to-fiber bonds and do not contain calender bonds or point bonds. These through-air bonds are much weaker than normal (i.e., not lightly bonded) calender bonds or point bonds and are more prone to breaking. Thus, during the three-dimensional element forming process, the through-air bonds can be easily broken and allow the fibers to move without causing fiber breakage or causing a small amount of fiber breakage. This fiber movement (whether in a through-air bonded nonwoven or in a lightly bonded nonwoven) may allow for a reduction in basis weight in the area adjacent the three-dimensional element to provide an area of increased permeability adjacent the three-dimensional element. In other words, this fiber movement may allow for basis weight variations in the nonwoven material adjacent the three-dimensional element.
The present disclosure is directed, in part, to laminates for absorbent articles and absorbent articles comprising the laminates. The laminate may have two or more nonwoven materials, and at least one of the nonwoven materials is a through-air bonded nonwoven material. The through-air bonded nonwoven material may comprise or consist of carded fibers or spunbond fibers and the other layer comprises or consists of carded fibers or spunbond fibers. Any of the layers may comprise, for example, nanofibers or meltblown fibers. The laminate may have three-dimensional elements, land areas comprising the fibers, and regions of increased permeability comprising the fibers and formed adjacent to the three-dimensional elements and positioned intermediate at least some of the land areas and at least some of the three-dimensional elements. The increased permeability areas may have a lower basis weight than the land areas. The first nonwoven may include normal (i.e., not lightly bonded) calender bonds or spot bonds, and the second nonwoven may be free of normal calender bonds and spot bonds and may include only fiber-to-fiber bonds. The second nonwoven may also be a through air bonded material that does not contain normal calender bonds and spot bonds. The laminate may comprise more than two nonwoven materials. Herein, including the claims, the first and second nonwoven materials may be referred to as "first" and "second", depending on which is discussed first.
The present disclosure relates in part to substrates for absorbent articles. The substrate may comprise a nonwoven material comprising fibers. The nonwoven material may comprise a lightly bonded material having calender bonds or point bonds, or may comprise a through-air bonded material comprising through-air bonds and lacking normal calender bonds or point bonds. The fibers may be spunbond fibers or carded fibers. The nonwoven material may include three-dimensional elements, a land area including the fibers and positioned in an area free of the three-dimensional elements, and an area of increased permeability including the fibers and positioned adjacent to at least some of the three-dimensional elements. In the landing zone, the nonwoven material has a first basis weight according to the micro CT test herein. In the areas of increased permeability, the nonwoven material has a second basis weight that is in a range of less than 75% to less than 25% (or other ranges herein) of the first basis weight of the landing areas according to the micro-CT test herein.
Drawings
The above-mentioned and other features and advantages of this disclosure, and the manner of attaining them, will become more apparent and the disclosure itself will be better understood by reference to the following description of exemplary forms thereof taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a plan view of an exemplary absorbent article in the form of a diaper in a flat, unfolded state with the wearer-facing surface facing the viewer;
FIG. 2 is a plan view of the exemplary absorbent article of FIG. 1 in a flat, unfolded state with the garment-facing surface facing the viewer;
FIG. 3 is a front perspective view of the absorbent article of FIGS. 1 and 2 in a fastened state;
FIG. 4 is a front perspective view of an absorbent article in the form of a pant;
FIG. 5 is a rear perspective view of the absorbent article of FIG. 4;
FIG. 6 is a plan view of the absorbent article of FIG. 4 in a flat, unfolded state with the garment-facing surface facing the viewer;
FIG. 7 is a cross-sectional view of the absorbent article taken along line 7-7 of FIG. 6;
FIG. 8 is a cross-sectional view of the absorbent article taken along line 8-8 of FIG. 6;
FIG. 9 is a plan view of an exemplary absorbent core of an absorbent article;
FIG. 10 is a cross-sectional view of the absorbent core of FIG. 9 taken along line 10-10;
FIG. 11 is a cross-sectional view of the absorbent core of FIG. 10 taken along line 11-11;
FIG. 12 is a plan view of an exemplary absorbent article of the present disclosure as a sanitary napkin;
FIG. 13 is an exemplary cross-sectional view taken in the front waist region of an absorbent article;
FIG. 14 is an exemplary cross-sectional view taken in the crotch region of an absorbent article;
FIG. 15 is an exemplary cross-sectional view taken in the back waist region of an absorbent article;
fig. 16 is a cross-sectional schematic view of an exemplary laminate of the present disclosure comprising two nonwoven materials;
FIG. 16A is a schematic cross-sectional view of an exemplary substrate of the present disclosure comprising a nonwoven material;
FIG. 17 is a cross-sectional schematic view of another exemplary laminate of the present disclosure comprising three nonwoven materials;
FIG. 18 is a cross-sectional schematic view of another exemplary laminate of the present disclosure comprising two nonwoven materials;
FIG. 19 is a cross-sectional schematic view of another exemplary laminate of the present disclosure comprising two nonwoven materials;
FIG. 19A is a schematic cross-sectional view of an exemplary substrate of the present disclosure comprising a nonwoven material;
fig. 20 is a top view photograph of a calender-bonded or point-bonded nonwoven material used in a laminate of the present disclosure;
FIG. 21 is a photograph of a cross-sectional view taken along line 21-21 of FIG. 20 and illustrating a calender bond or a point bond;
FIG. 22 is a side view photograph of a through air bonded nonwoven material used in a laminate of the present disclosure;
FIG. 23 is a photograph of a cross-sectional view taken along line 23-23 of FIG. 22 and illustrating a hot air bond;
fig. 24 is a bottom perspective view of another exemplary laminate of the present disclosure;
FIG. 25 is an exploded view of
FIG. 26 is a top perspective photograph of an exemplary substrate of the present disclosure including a nonwoven material having an area of increased permeability; and
fig. 27 is a top perspective photograph of a comparative example substrate that does not include the increased permeability regions of the present disclosure. The comparative example substrate was a 25gsm spunbond PE/PP bicomponent nonwoven including calender bonds.
Detailed Description
Various non-limiting forms of the present disclosure will now be described to provide a general understanding of the principles of the structure, function, manufacture, and application of the substrates and laminates for absorbent articles disclosed herein. One or more examples of these non-limiting forms are illustrated in the accompanying drawings. Those of ordinary skill in the art will understand that the substrates and laminates for absorbent articles described herein and illustrated in the drawings are non-limiting example forms and that the scope of the various non-limiting forms of the present disclosure is defined entirely by the claims. Features shown or described in connection with one non-limiting form may be combined with features of other non-limiting forms. Such modifications and variations are intended to be included within the scope of the present disclosure.
First, a general description of exemplary absorbent articles will be provided, and then substrates and/or laminates for absorbent articles or other consumer products will be discussed. Substrates for absorbent articles (i.e., single layers) may form a topsheet, an acquisition layer, a distribution layer, a secondary topsheet, a core cover, other suitable layers, or substrates in consumer products other than absorbent articles. Laminates (i.e., more than one layer) for absorbent articles may be formed, for example, a topsheet laminate, a topsheet/acquisition layer laminate, a topsheet/secondary topsheet laminate, an outer cover nonwoven laminate, another laminate for other components of an absorbent article, or a laminate for consumer products other than absorbent articles.
General description of absorbent articles
An exemplary
The
The
In other cases, the absorbent article may be in the form of a pant having permanent or refastenable side seams. Suitable refastenable seams are disclosed in U.S. patent application publication 2014/0005020 and U.S. patent 9,421,137. Referring to fig. 4-8, an exemplary
Binding belt
Referring to fig. 7 and 8, the front and
The front and back inner belt layers 66, 67 and the front and back outer belt layers 64, 65 may be joined using adhesives, thermal bonding, pressure bonding, or thermoplastic bonding. Various suitable belt layer constructions can be found in U.S. patent application publication 2013/0211363.
The front
As disclosed in U.S. patent 7,901,393, the longitudinal length (along the central longitudinal axis 50) of the
The front and back outer belt layers 64, 65 may be separated from each other such that the layers are discrete, or the layers may be continuous such that the layers extend continuously from the front
The
The
Alternatively, discrete side panels may be connected to the side edges 22 and 24 of the chassis instead of attaching the
Topsheet
The
The topsheet may be one of the exemplary laminates described below, or may form part of a laminate in combination with, for example, an acquisition material or layer, a secondary topsheet, or another layer or material.
Negative film
The
Outer cover material
The outer cover material (sometimes referred to as a backsheet nonwoven) 40 may comprise one or more nonwovens joined to the
Absorbent core
As used herein, the term "absorbent core" 30 refers to the component of the
Referring to fig. 9-11, the
Barrier leg cuff/leg elastics
Referring to fig. 1 and 2, for example, the
Elastic waistband
Referring to fig. 1 and 2, the
Collection material
Referring to fig. 1, fig. 2, fig. 7, and fig. 8, one or
In the case of the laminates discussed herein, the acquisition material may be combined with the topsheet to form a laminate.
Landing zone
Referring to fig. 1 and 2, the
Wetness indicator/graphic
Referring to fig. 1, the
Front and back ear
Referring to fig. 1 and 2 mentioned above, the
Sensor with a sensor element
Referring again to fig. 1, the absorbent articles of the present disclosure may include a
Packaging piece
The absorbent articles of the present disclosure can be placed into a package. The package may comprise a polymer film and/or other materials. Graphics and/or indicia relating to the characteristics of the absorbent article may be formed on, printed on, positioned on, and/or placed on the exterior portion of the wrapper. Each package may include a plurality of absorbent articles. The absorbent articles can be stacked under compression to reduce the size of the packages while still providing a sufficient amount of absorbent articles per package. By enclosing the absorbent articles under compression, the caregiver can easily handle and store the package while also providing dispensing savings to the manufacturer due to the size of the package.
Sanitary napkin
Referring to fig. 12, the absorbent article of the present disclosure may be a
The secondary topsheet may be combined with the topsheet to form the laminates discussed herein. In other instances, the laminate discussed herein may form only the topsheet of a sanitary napkin.
Exemplary sectional views of absorbent articles
Fig. 13-15 illustrate exemplary cross-sectional views of absorbent articles within the scope of the present disclosure. Figure 13 is an exemplary cross-sectional view taken in the
Substrate and/or laminate for absorbent article
Provided herein are substrates and/or laminates for absorbent articles or other consumer products. The substrate may comprise a through-air bonded nonwoven material or a lightly bonded nonwoven material. The absorbent articles discussed herein may include the substrate as, for example, a topsheet, an acquisition material, a secondary topsheet, an outer cover nonwoven, and/or other components. Absorbent articles discussed herein may include the laminate as, for example, a topsheet laminate, a topsheet/acquisition material laminate, a topsheet/secondary topsheet laminate, a topsheet and other material laminate, an outer cover nonwoven material laminate, and/or other components. The laminate may comprise two or more nonwoven materials, wherein at least one of the nonwoven materials is through air bonded and does not contain normal calender or point bonds. The substrate and/or laminate may also be used as a wipe, cleaning or dusting substrate, or in other consumer products including nonwovens. In some cases, the substrate and/or laminate may comprise a wet laid nonwoven, an air laid nonwoven, a meltblown nonwoven, a nanofiber nonwoven, a spunbond nonwoven, a carded nonwoven, a spunlaced nonwoven, or a combination thereof.
Fig. 16-19 are schematic cross-sectional examples of a portion of a laminate of the present disclosure. Fig. 16-19 also illustrate substrates (i.e., monolayers) of the present disclosure (with material substantially removed in areas that do not have increased permeability). It should be understood that the substrate may be used/manufactured independently of the laminate by providing only a single layer substrate with regions of increased permeability (see fig. 16A and 19A, which show only one nonwoven from fig. 16 and 19, respectively). The substrate 201 of fig. 16A and 19A will be further described below.
The laminate 200 may include a
Fig. 16 illustrates the portion of the
Fig. 17 illustrates a portion of a
Fig. 16A illustrates an exemplary substrate 201 taken from fig. 16. The substrate 201 is the
Fig. 19A illustrates an exemplary substrate 201 taken from fig. 19. The substrate 201 is the
Fig. 20 illustrates a top view photograph of a calender-bonded or point-bonded
Unlike normal calender bonds or point bonds, the fibers of the web may be through-air bonded to form a nonwoven. The through-air bonding process creates more and smaller bonds in the nonwoven than normal calender bonds or point bonds. Typically, through-air bonds are created by passing heated air or hot air through the web. Generally, by melting the intersection points of the fibers, through-air bonds are formed where the fibers 223 of the web contact each other. The single through-air bonds are much weaker than normal calender bonds or point bonds because through-air bonds are each formed only between a small number of fibers (e.g., 2 fibers to 5 fibers). Figure 22 is a side view photograph of a through air bonded nonwoven 222 including a plurality of through air bonds 224. Fig. 23 is a cross-sectional photograph taken along line 23-23 of fig. 22. As can be seen in fig. 23, through-air bonds 224 occur at least some of the fiber intersections and are quite numerous. The through-air bonded nonwoven material may include only fiber-to-fiber bonds and may not include any other bonds. The through-air bonded nonwoven materials used in the laminates of the present disclosure may comprise continuous fiber nonwoven materials (e.g., spunbond materials) or may comprise carded fibrous nonwoven materials. The through-air bonded nonwoven material may also comprise other types of fibers such as natural fibers (e.g., cotton, pulp, bamboo) or blends of natural and synthetic fibers.
Also, unlike normal calender bonds or point bonds, the fibers of the web may be lightly calender bonded or point bonded to form a nonwoven. In this case, the raised points on the bonding roll may apply less pressure to the web than normal calender bonds or point bonds (i.e., fig. 21). By applying less pressure to the web, the web is less densified than a normal calender bond or point bond and a lightly bonded calender bond or point bond is formed. During three-dimensional element formation, the fibers in the lightly bonded calender or spot bonds are able to break or move more within the bond than the fibers in the normal calender or spot bonds. Typically, the fibers within the normal calender bonds or point bonds break during the formation of the three-dimensional element, resulting in loose fiber ends and reduced softness. By calendering or point bonds with light bonds, fiber breaks can be reduced and improved softness can be achieved.
Due to the nature of through-air bonds and/or lightly bonded calender or point bonds, these nonwovens may allow for more fiber movement when creating three-dimensional elements in these nonwovens. In other words, through-air bonds and/or lightly bonded calender bonds or point bonds in the nonwoven material may cause the basis weight of the nonwoven material to become close to or adjacent to the three-dimensional element. It is believed that this fiber movement and/or basis weight variation is the result of the thermal air bonds between the individual fibers breaking upon application of the applied strain (i.e., three-dimensional element formation). In nonwovens that include lightly bonded calender bonds or point bonds, the same fiber migration may be noted. In normal calender-bonded or point-bonded nonwovens, the same phenomenon is not seen due to the strength of the calender bonds or point bonds. Thus, the substrates and/or laminates of the present disclosure may employ at least one through air bonded nonwoven or at least one nonwoven comprising lightly bonded calender bonds or point bonds. The second or additional material of the laminate may be a through air bonded nonwoven, a nonwoven comprising lightly bonded calender bonds or point bonds, or may be a normal calender or point bonded nonwoven. Through-air-bonded nonwovens can be bonded at low temperatures (i.e., the gas passing through the nonwoven is at a low temperature), thereby creating low strength bonds between the individual fibers. This may cause the fibers to be substantially pulled out of the bond and allow for improved fiber mobility over normal calender bonds or point bonds.
Referring again to fig. 16, the
Referring to fig. 17, the first nonwoven and/or the third nonwoven may comprise a through air bonded nonwoven, a normal calender bonded or point bonded nonwoven, or a nonwoven comprising lightly bonded calender bonds or point bonds. If the first nonwoven and/or the third nonwoven comprise through-air bonded nonwovens or nonwovens comprising lightly bonded calender bonds or point bonds, areas of increased permeability may be created in the first nonwoven and the third nonwoven in the area that overlaps the area of increased
The
The region of increased permeability allows for more rapid acquisition of bodily exudates, particularly in combination with the three-dimensional element. Consumers desire that body exudates be quickly removed from the wearer-facing surface of the absorbent article and quickly absorbed by the absorbent article. When the
Referring generally to fig. 16-19, the
Referring generally to fig. 16 and 18, the
For the
Referring generally to fig. 17 and 19, the
For the
Referring generally to fig. 16-19A, the
For the nonwoven materials discussed in the preceding paragraphs, the second basis weight can be from less than 50% to less than 5%, from less than 45% to less than 5%, from less than 40% to less than 5%, from less than 35% to less than 5%, from less than 30% to less than 5%, from less than 25% to less than 5%, from less than 20% to less than 5%, from less than 15% to less than 5%, from less than 50% to less than 10%, from less than 45% to less than 10%, from less than 40% to less than 10%, from less than 35% to less than 10%, from less than 30% to less than 10%, from less than 25% to less than 10%, from less than 20% to less than 10%, from less than 15% to less than 10% of the first basis weight and/or the third basis weight, specifically reciting the specified ranges and all 0.1% increments formed therein or therefrom. All basis weight percentages discussed herein are tested according to the micro CT herein.
The fibers of the nonwoven materials disclosed herein can include resins including polyolefins, PP, PE, copolymers, polyesters, bio-derived materials, natural materials, or blends thereof.
The fibers of the nonwoven materials disclosed herein can include bicomponent fibers, such as, for example, PP/PE, PET/coPET, or PLA/PE. For example, the bicomponent fibers may have a core/sheath configuration, a concentric or eccentric core/sheath configuration, a sea-island configuration, and/or any other suitable bicomponent configuration in which at least a portion of the surface of the fibers comprises a low melting component.
As used herein, the term "non-round fibers" describes fibers having a non-round cross-section and includes "shaped fibers" and "capillary channel fibers". Such fibers may be solid or hollow, and they may be trilobal, delta-shaped, and may be fibers having capillary channels on their outer surfaces. The capillary channel can have various cross-sectional shapes, such as "U-shaped," H-shaped, "" C-shaped, "and" V-shaped. The fibers may be round, hollow, or shaped such as trilobal, ribbon, capillary channel fibers (e.g., 4 DG). The fibers may comprise microfibers or nanofibers. The fibers may also have a circular cross-sectional shape.
The basis weight of the overall substrate or laminate of the present disclosure may vary depending on the intended target of the substrate or laminate. The basis weight of the overall laminate or substrate may range from about 10gsm (grams per square meter) to about 120gsm, from about 10gsm to about 100gsm, from about 15gsm to about 75gsm, from about 15gsm to about 65gsm, from about 15gsm to about 50gsm, from about 20gsm to about 40gsm, specifically enumerating the specified ranges and all ranges formed therein or therefrom, all 0.1gsm increments.
The various nonwoven materials of the laminates discussed herein may have the same color or different colors. In some cases, the first nonwoven may be a first color that is not white and the second nonwoven may be white or may be a second color that is not white. For example, the first nonwoven may be white and the second nonwoven may be cyan, or vice versa. As another example, the first nonwoven may be cyan and the second nonwoven may be blue, or vice versa. The substrates discussed herein may also be non-white in color.
The various nonwoven materials of the laminate may have different opacities. For example, a first nonwoven of the laminate may have a different opacity than a second nonwoven of the laminate. The first nonwoven and the second nonwoven may have an opacity difference within the following ranges: in the range of from about 10% to about 70%, from about 15% to about 60%, from about 15% to about 50%, from about 20% to about 50%, specifically reciting all 0.1% increments within the specified ranges and all ranges formed therein or therefrom.
Fig. 24 and 25 illustrate another
Suitable exemplary processes for producing the laminates and substrates of the present disclosure are described in detail in U.S. Pat. No. 7,553,532 to Turner et al (see, e.g., fig. 7-10 and related disclosure).
The fibers of the three-dimensional element may have a substantially constant fiber diameter in view of the fiber movement allowed using the first
Comparison of the sum of bond Strength and the sum of fiber breaking Strength
Substrates and/or laminates comprising nonwoven materials containing regions of increased permeability may include bonds that join the fibers. The nonwoven material may be a through air bonded nonwoven material or a nonwoven material including lightly bonded calender bonds or point bonds. The bonds may each have a bond strength. The fibers may each have a fiber yield strength or a break strength. The sum of the bond strengths in the region of the nonwoven may be less than the sum of the fiber yield strengths or breaking strengths in the region of the nonwoven. The strength of the individual bonds may be less than the yield or break strength of the individual fibers, such that the individual bonds separate and the individual fibers are allowed to move rather than stretch (i.e., yield) or break. The region may at least partially or completely overlap the region of increased permeability. By having a bond strength sum that is less than the fiber breaking strength sum, it is believed that bonds in the area typically break before fibers in the area, resulting in improved fiber movement when creating the three-dimensional element and thus reducing fiber breakage during three-dimensional element creation.
Film
Laminates may include films combined with through-air bonded nonwovens or nonwovens that include lightly bonded calender bonds or point bonds. The film may be the first layer and the through air bonded nonwoven or nonwoven including lightly bonded calender bonds or point bonds may be the second layer. The laminate may include landing zones and three-dimensional elements in both layers, as well as areas of increased permeability in the through-air bonded nonwoven or nonwoven including lightly bonded calender bonds or point bonds.
Test method
All samples were conditioned for 24 hours in an environment maintained at 23 ℃ ± 2 ℃ and 50% ± 2% relative humidity prior to testing.
Fiber diameter and denier testing
The diameter of the fibers in the nonwoven sample was determined by using a Scanning Electron Microscope (SEM) and image analysis software. The magnification of 500 to 10,000 times is chosen so that the filaments are suitably magnified for measurement (so that the diameter ("width") of the fiber spans at least 3-5 pixels). These samples were sputtered with gold or palladium-gold compounds to avoid charging and vibration of the fibers in the electron beam. A manual protocol for determining fiber diameter was used. Using a mouse and cursor tool, the edge of the randomly selected fiber is searched and then measured across its width (i.e., the fiber direction perpendicular to the point) to the other edge of the fiber. For non-circular fibers, the area of the cross-section was measured using image analysis software by analyzing the Z-plane cross-section of the fiber. The effective diameter is then calculated by calculating the diameter as if the found region was a circular ring. Scaling the calibration image analysis tool provides scaling to obtain the actual reading in micrometers (μm). Thus, several fibers in a three-dimensional element of a nonwoven material were randomly selected across a nonwoven sample using SEM. At least two samples from the nonwoven material in the three-dimensional element were cut and tested in this manner. A total of at least 100 such measurements were made and then all data were recorded for statistical analysis. The recorded data were used to calculate the mean of the fiber diameters, the standard deviation of the fiber diameters and the median of the fiber diameters. Another useful statistic is to calculate the population number of fibers below a certain upper limit. To determine this statistic, the software is programmed to count how much of the fiber diameter of the result is below an upper limit, and the count (divided by the total number of data and multiplied by 100%) is reported as a percentage below the upper limit, such as, for example, a percentage below 1 micron diameter or% -submicron.
If the results are intended to be reported in denier, the following calculations are made.
Fiber diameter in denier (cross-sectional area in m 2) density (in kg/m 3) 9000m 1000 g/kg.
For round fibers, the cross-sectional area is defined by the following equation:
A=π*(D/2)∧2。
for polypropylene, for example, a density of 910kg/m3 may be used.
Given the fiber diameter in denier, the fiber diameter of the physical circular ring in meters (or microns) is calculated from these relationships and vice versa. We denote the measured diameter (in microns) of a single circular fiber as D.
In the case of fibers having non-circular cross-sections, the measurement of fiber diameter is determined and set equal to the hydraulic diameter, as discussed above.
The fiber cross-sectional shape can also be determined from the above cross-sectional image in the Z-plane. The cross-sectional shape of the nonwoven fibers near the first surface of the nonwoven material should be evaluated. The cross-sectional shape of the fibers should be recorded near the first surface of the nonwoven. The cross-sectional shape of the nonwoven fibers near the second surface of the nonwoven material should be evaluated. The cross-sectional shape of the fibers near the second surface of the nonwoven should be recorded.
Micro CT test
The micro CT measurement method calculates basis weight values within different regions of the laminate or substrate sample, such as three-dimensional elements, land areas, and regions of increased permeability formed adjacent to the three-dimensional elements and positioned intermediate at least some of the land areas and at least some of the three-dimensional elements. Basis weight was based on analysis of 3D x radiation sample images obtained on a micro CT instrument (a suitable instrument is Scanco μ
Sample preparation:
To obtain the samples for measurement, a single layer of the dried samples was spread flat and die cut/punched into circular pieces with a diameter of about 20 mm. If the sample is in the form of a laminate, a circular sample of about 20mm in diameter, including all layers of the laminate, is die cut/punched. The laminate sample can be analyzed as a complete multilayer structure or separated into individual substrate layers as long as the separation of the laminate layers does not physically deform or alter the structure of the individual layers.
If the substrate/laminate is a layer of an absorbent article, such as a topsheet, backsheet nonwoven, acquisition layer, distribution layer, or other component layer; the absorbent article is secured to the rigid planar surface with the tape in a planar configuration. The individual substrates/laminates were carefully separated from the absorbent article. If desired, a scalpel and/or a cryogenic spray (such as Cyto-Freeze, Control Company, Houston TX) may be used to remove the substrate/laminate from the additional underlying layers to avoid any longitudinal and lateral extension of the substrate/laminate. Once the substrate/laminate has been removed from the absorbent article, the die cutting/punching of the sample begins as described above.
If the substrate/laminate is in the form of a wet wipe, a new package of wet wipes is opened and the entire stack is removed from the package. A piece of wipe was removed from the middle of the stack, spread flat and allowed to dry completely, and then die cut/punched out the sample for analysis.
The sample may be cut from any location containing the area to be analyzed. Care should be taken to avoid folding, wrinkling or tearing when selecting the sampling location.
Image acquisition:
The micro-CT instrument was set up and calibrated according to the manufacturer's instructions. The sample is placed in a suitable holder between two rings of low density material. This would allow the central portion of the sample to be placed horizontally and scanned without having any other material directly adjacent to the upper and lower surfaces of the sample. Measurements should be taken in this area. The 3D image field of view is about 15mm on each side in the XY plane, the resolution is about 3400 pixels by 3400 pixels, and a sufficient number of 4.5 micron thick slices are collected that completely encompass the z direction of the sample. The reconstructed 3D image resolution contains isotropic voxels of 4.5 microns. Images were acquired with a 45kVp and 88-200 μ A light source without the need for an additional low energy filter. These current and voltage settings can be optimized to produce maximum contrast in the projection data, where enough x-rays penetrate the sample, but once optimized, all substantially similar samples remain constant. A total of 1500 projection images were obtained with an integration time of 500ms and 4 averages. The projection images are reconstructed into 3D images and saved in 16 bit RAW format to preserve the complete detector output signal for analysis.
Image processing:
The 3D data set is loaded into image analysis software and trimmed (cropped) into a rectangular prismatic 3D image of the analysis area by removing the surrounding grippers and low density mounting material from the 3D data set. The cropping is performed such that the maximum amount of sample in the analysis area remains in the 3D image and the empty space above and below the sample is minimized. The cropped 3D image is scaled from 16 bits to 8 bits and thresholded using the Otsu method, which calculates a threshold level that minimizes the weighted intra-class variance to separate and remove air-induced background signals, but retains the signal from the fibers within the sample image.
The thresholded 3D image is oriented such that the upper surface is as close to parallel with the XY plane as possible.
A basis weight image is generated from the thresholded 3D image. To generate this image, the value of each voxel in the XY plane slice is added to all its corresponding voxel values in other z-direction slices that include the signal from the sample. This will create a 2D image in which each pixel now has a value equal to the cumulative signal of the entire sample.
To convert the raw data values in the basis weight image to actual values, a basis weight calibration curve is generated. A substrate/laminate having a substantially similar composition and uniform basis weight as the sample being analyzed was obtained. At least ten replicate samples of the base of the calibration curve were obtained following the procedure described above. Basis weight was accurately measured by: the mass of each of the monolayer calibration samples was taken to be approximately 0.0001g and divided by the sample area and converted to grams per square meter (gsm) and the average was calculated to the nearest 0.01 gsm. micro-CT images of a single layer of the calibration sample substrate were acquired according to the protocol described above. The micro CT images were processed according to the protocol described above and a basis weight image was generated comprising the raw data values. The actual basis weight value for this sample is the average basis weight value measured on the calibration sample. Next, two layers of calibration samples are stacked on top of each other and micro-CT images of the two layers of calibration material are acquired. The basis weight raw data images of the two layers were generated together with an actual basis weight value equal to twice the average basis weight value measured on the calibration sample. This step of stacking single layer calibration substrates is repeated to acquire micro-CT images of all the layers, generating raw data basis weight images of all the layers with the actual basis weight value equal to the number of layers multiplied by the average basis weight value measured on the calibration sample. A total of at least four different basis weight calibration images are obtained. The basis weight values of the calibration samples must include values above and below the basis weight values of the initial samples to be analyzed to ensure accurate calibration. A calibration curve was generated by performing a linear regression on the raw data with the actual basis weight values of the four calibration samples. If the entire calibration process is not repeated, the linear regression must have an R of at least 0.952The value is obtained. The calibration curve is now used to convert the raw data values to actual basis weights.
Basis weight of micro CT:
The analysis is started by identifying the region. The area to be analyzed may be a three-dimensional element, a land area, or an area of increased permeability formed adjacent to the three-dimensional element and positioned intermediate at least some of the land area and at least some of the three-dimensional element. Next, the boundaries of the region to be analyzed are identified. Once the boundaries of the region are identified, an elliptical or circular "region of interest" (ROI) is drawn inside the region. The ROI should have at least 0.1mm2And is selected for measuring the area having a basis weight value representative of the identified area. The average basis weight within the ROI was calculated. This value is recorded as the basis weight of the region to the nearest 0.01 gsm.
- 上一篇:一种医用注射器针头装配设备
- 下一篇:胶囊填充装置