IMPROVED FABRIC WITH REINFORCED INTERLACES

Abstract

A fabric having first section and having first pores created by the interlacings of yarn in a first pattern, and having a first average pore size. The fabric also includes a second fabric section having second fabric pores created by the interlacings of yarn in a second pattern, and a second average pore size. The number of first interlacings of yarn is greater than the number of second interlacings of yarn. The first fabric provides strength to the second fabric. The first fabric pattern designed to mitigate any unravel of a second pore yarn in the event it is severed.

Description

FIELD OF THE INVENTION

The embodiments described herein are directed to a fabric having reinforced interlaces and at least two different average pore sizes created by at least two different stitch or weave patterns. An interface is created where the spacing of the nodal points change. The reinforced interlaces help to strengthen the larger pores at the interface and reduce the potential for fray or unravel.

BACKGROUND OF THE INVENTION

Medical textiles are used in a multitude of applications both for external application as well as internal and implantable applications. Today, due to the advancement in technology and the rising cost of health care, more medical and surgical procedures are done using minimally invasive techniques. This includes the use of endoscopes, and the like, to view, explore and perform surgical procedures on a patient within the parameters of an endoscope or other minimally invasive instrument.

In such an application, minimally invasive procedures require the instruments and other components of the process to be capable of significant compression. This is to enable the components to travel through a catheter to the site of the procedure. Further the components must be designed to unroll or otherwise decompress so as to function as designed once they arrive at the predetermined location.

In this regard, many components of minimally invasive procedures are specially adapted to meet the needs of the particular procedure or instrument used for a predetermined purpose. For example, in certain exploratory procedures, a capturing device may be used to enclose a tissue sample which will be analyzed by the surgeon once it is retrieved from the body. In all cases, the materials must be extremely light weight and relatively thin or capable of being compacted into a thin profile for travel via a catheter. Furthermore, the components must be strong enough to function as designed so that their slightness in weight does not detract from their structural integrity. These two characteristics are difficult to design as each compromises the other. A fabric that is designed to be strong is typically heavier in weight and bulk. Conversely, a fabric that is light weight and capable of assuming a slight profile for travel via a catheter is typically not strong and does not hold up well under tension.

In materials and textile components used in minimally invasive applications, another issue is that of unravel or fray of the structure. This is especially true with very open mesh or net structures. It is undesirable to have a loose yarn or have a fabric unraveling. The loose yarn may cause a blockage of a passageway, for example in applications relating to arterial or venal repair. In addition, any unravel of a textile component may compromise the structural integrity and ultimately the function of the component or device.

One patent addresses the issue of fray or unravel in U.S. Pat. No. 5,456,711 entitled “Warped Knitted Carotid Patch Having Finished Selvage Edges.” The patent solves the need for cutting by providing knit mesh patches of predetermined width with finished edges, and thus eliminates the problem of unravel or fray.

It is desirable to provide a light weight fabric capable of assuming a slight profile for travel via a catheter while maintaining a level of strength needed to perform as designed and to prevent any fray or unravel of any yarn. It should be noted that the term fray as described herein refers to the ability of the fabric in the areas of more concentrated interlacings or nodal points to absorb strain from the areas of less concentrated interlacings and nodal points and reduce the potential for the stitches to loosen or come undone.

Further, it is desirable to provide a fabric capable of use in a minimally invasive procedure that may be cut for manufacturing purposes and reduce the potential for any fray or unravel.

SUMMARY OF THE INVENTION

The embodiments described herein relate to a fabric having a first fabric section having first fabric pores created by the first interlacings of yarn in a first pattern, and having a first average pore size. The fabric further includes a second fabric section having second fabric pores created by the second interlacings of yarn in a second pattern, and a second average pore size. The number of first interlacings of yarn exceeds the number of second interlacings of yarn. The first interlacings enhance the integrity of the second fabric section and reduce the potential for fray.

The fabric of the embodiments described herein has a configuration where the first fabric section may surround the second fabric section.

The fabric of the embodiments described herein may have a difference in average pore size between the first average pore size and the second average pore size, where the difference is at least 100%.

The fabric of the embodiments described herein may have a difference in weight between the first and second fabric sections, where the difference is at least 50%.

The fabric of the embodiments described herein may have a difference in thickness between the first and second fabrics, where the difference may be at least 10%.

The fabric of the embodiments described herein may have a difference in the burst strength between the first and second fabric sections, where the difference is at least 50%.

The fabric of the embodiments described herein may have a difference in the number of interlacings, where the number first interlacings is at least 50% more than the number of second interlacings.

The fabric of the embodiments described herein may have a difference in the percentage of open area, where the open area of the first fabric section may be about at least 7% less than the percentage of open area of the second section.

The fabric of the embodiments described herein may be knit or woven. The embodiments further provide for a method of creating a reinforced mesh fabric, by creating a first fabric section having first fabric pores created by the first interlacings of yarn in a first pattern, and having a first average pore size, and creating a second fabric section having second fabric pores created by the second interlacings of yarn in a second pattern, and a second average pore size, wherein the number of first interlacings of yarn is greater than the number of second interlacings of yarn.

Other objects, features and advantages of the embodiments described herein will become more apparent upon reading the following detailed description, when taken in conjunction with the drawings and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is front view of a first embodiment fabric.

FIG. 1B is a contracted view of the embodiment of FIG. 1A.

FIG. 1C is an enlarged view of the embodiment of FIG. 1A.

FIG. 1D is a diagrammatic representation of FIG. 1C.

FIG. 1E is an enlargement of FIG. 1A at the interface of the first and second pores along the crosswise direction.

FIG. 1F is a diagrammatic representation of FIG. 1E.

FIG. 1G is an enlarged view of FIG. 1A at the interface of the first and second pores along the machine direction.

FIG. 1H is a diagrammatic representation of FIG. 1G.

FIG. 2A is an enlarged view of a representative second pore.

FIG. 2B is an enlarged view of a representative first pore.

FIG. 3 is a front view of the second embodiment.

FIG. 4 is a diagrammatic representation of the threading layout for the embodiment of FIG. 3.

FIG. 5 is a diagrammatic representation of the guide bar movement for the embodiment of FIG. 3.

FIG. 6 is an enlarged view of FIG. 3.

FIG. 7 is a front view of a third embodiment.

FIG. 8 is a front view of a fourth embodiment.

DETAILED DESCRIPTION

Referring now to the drawings in which like numerals indicate like parts throughout the several views, FIG. 1A shows a first embodiment 10 of the fabric having first 12 and second 14 sections. The first embodiment 10 is a knit mesh made of a monofilament PET yarn. The first section 12 is made using a first stitch pattern and forming first pores 16. The second section 14 is formed by using a second stitch pattern and forms second pores 18.

The particular stitch pattern used for the first embodiment 10 is set forth below.

Guide bar 1=(2−1/1−2/2−1/1−0/1−2/2−1/1−2/2−3)×17 (2−1/1−0/1−2/2−3)×12

Guide bar 2=(1−2/2−1/1−2/2−3/2−1/1−2/2−1/1−0)×17 (1−2/2−3/2−1/1−0)×12

Guide bar 3=(2−1/1−0/1−2/2−3)×46

Guide bar 4=(1−2/2−3/2−1/1−0)×46

It should be noted that any number of stitch patterns may be used to create a fabric as described herein and that the stitch pattern described above is not intended to limit the scope of the embodiment in any way. As will be appreciated by one skilled in the art, the stitch pattern may be modified to design a fabric where dimensions may need to be altered but the function of the fabric remains essentially the same. FIG. 1B is a retracted view of the first embodiment 10 and shows the first 12 and second 14 sections. FIG. 1C is a further enlarged view of the first embodiment 10 and particularly shows a corner where the first 12 and second 14 sections interface. FIG. 1D is a computer generated representation of FIG. 1C. FIG. 1E is an enlarged view of the first embodiment 10 at the interface of the first 12 and second 14 sections along a cross direction. FIG. 1F is a computer generated representation of FIG. 1E. FIG. 1G is an enlarged view of the first embodiment 10 at the interface of the first 12 and second 14 sections along the machine direction. FIG. 1H is a computer generated representation of FIG. 1G.

Generally, pores are defined as the opening created between the knitted pillars of the mesh. Each pillar consists of the loops formed in a single needle. The spacing between the yarns within each knitted pillar is not considered a pore in the formed mesh described herein. FIG. 2A shows a representative first pore 16 formed by the interlacing of knit first pillars 20 of the first embodiment 10. FIG. 2B shows a representative second pore 18 formed by the interlacing of knit second pillars 22. As shown in FIG. 1A, the first section 12 surrounds the second section 14, as shown by interface line 15. The first section 12 encapsulates the second section 14 by using reinforcing interlaces which work in opposition to one another to support the second section 14 by providing additional points within the section where the yarns interlace. The first section 12 of additional interlaces provides enhanced structural support to the second pores 18 when stressed. In addition, the additional interlaces of the first section 12 mitigate or prevent fray or unravel by absorbing any cut yarn or end from further unravel by absorbing the tension into a point of interlacing or node, and discouraging further travel of the end of frayed yarn.

The first section 12 has a greater density than the second section 14 because the first pores 16 are smaller and the number of interlacings is greater over a fixed area. In the first embodiment 10, the number of interlacings in the first section 12 is approximately 26 per inch, while the number of interlacings in the second section is approximately 14 per inch. As such, the first section 12 also has a greater weight than the second section 14.

Several tests conducted on the fabric of the first embodiment 10. The results are set forth in Table A below.

TABLE A
	# of				%
Parameter	Samples	Test Method	Second Section	First Section	Difference
Filament	N = 5	N/A	Monofilament	Monofilament	n/a
Configuration
Denier	N = 5	ASTM	20	20	n/a
		D1577-07
Material	n/a	N/A	PET	PET	n/a
Minimum	N = 20	Microscopy	5.74	1.12	−135%
pore size
(mm2)
Maximum	N = 20	Microscopy	7.25	1.95	−115%
pore size
(mm2)
% Open Area	N = 5	Microscopy	93%	87%	−7%
Weight (g/m2)	N = 5	N/A	5.96	10.83	58%
Thickness	N = 5	ASTM	0.137	0.157	14%
(mm)		D1777-96
		Option 1
Burst Strength	N = 5	ASTM	6.5	13.1	67%
(PSI)		D3786-06
% Elongation	N = 5	ISO 7198	54.1	75.8	33%
@ break
Interlacings	N = 5	Count Pick	14	26	60%
per inch in		Glass
width

Table C below provides elongation data of the first 12 and second 14 sections of the first embodiment in pounds 10 over elongation. As can be seen in the graph, the first section maintains its integrity under strain for a longer period of time given the same rate, than the second section.

A second embodiment 24 provides for a different stitch pattern as shown in FIG. 3. The second embodiment 24 has a first section 26 having first pores 27 and a second section 28 having second pores 29.

The stitch pattern adopted to create the second embodiment 24 is as follows:

Guide Bar 1=(1−0/0−1/1−0/0−1/1−2/2−1/1−2/2−1)×3//

Guide Bar 2=0−1/1−2/2−3/3−4/4−5/5−6/6−7/7−8/8−7/7−8/8−7/7−8/8−7/7−6/6−5/5−4/4−3/3−2/2−1/1−0/0−1/1−0/0−1/1−0//

Guide Bar 3=8−7/7−6/6−5/5−4/4−3/3−2/2−1/1−0/0−1/1−0/0−1/1−0/0−1/1−2/2−3/3−4/4−5/5−6/6−7/7−8/8−7/7−8/8−7/7−8//

FIG. 4 is a diagrammatic representation of the threading layout of the second embodiment 24.

FIG. 5 is a diagrammatic representation of the guide bar movement of the second embodiment 24. Finally, FIG. 6 is an enlarged view of the second embodiment 24 illustrating in greater detail the first section 26 and the second section 28. The first section 26 has a smaller pore size and a greater number of interlaces or nodes than the second section 28. The second section 28 has fewer interlaces than the first section 26 and has a larger pore size.

It should further be noted that an area having a greater interlaces or nodal points may also act as a visual or tactile aid at the boundary between the areas where the number of nodes change. In manufacturing applications, this interface helps a worker to more efficiently or effectively attach a fabric piece onto a frame or device. This interface may aid the worker in more effectively installing the mesh piece onto a frame or other object which will result in a higher quality product.

The use of a greater number of nodal points as a visual and/or tactile aid may be incorporated into all facets of manufacturing where fabric having fewer nodal points or fewer interlaces is manipulated onto a frame or other device. The reinforcement area where the nodal points are greater helps to provide visual guidance to the person threading the fabric onto the wire or tube. The higher interlacing area provides visual guidance to the worker so as to ensure that the pores are threaded properly and thus the product quality is greater.

Variation on the number of interlaces in a given fabric at a particular location may also help to provide a visual or tactile aid to ensure that the less dense area is oriented properly. The surgeon may be able to look at the fabric or feel the fabric and determine by the pattern whether the mesh is oriented properly. When the mesh is oriented properly, the success rate of the procedure increases and thus patient quality of life is enhanced.

It should also be noted that the fabrics described herein may apply to both woven and knitted fabrics. With respect to knit fabrics, different stitch patterns may be used as applications require. The stitch pattern and density impact the knit mesh qualities of strength, pore size, stability and elongation. Where such properties need to be altered, the stitch pattern and/or density are altered

FIGS. 6 and 7 show third and fourth embodiments in a woven construct. FIG. 6 discloses a third embodiment 30 having a first section 32 having a tighter weave and more interlacings and nodal points. The second section 34 of the third embodiment 30 has a more open weave with fewer interlaces and nodal points. The first section 32 of the third embodiment 30 has a 1,1 weave, and the second section 34 has a 2,2 weave. FIG. 6 also shows the weave pattern of both first 32 and second 34 sections.

FIG. 7 is another example of a woven embodiment and provides a view of the fourth embodiment having a first section 38 having a tighter weave surrounding a second section 40 of a more open weave. As can be seen from FIG. 7, the interfaces between the first 38 and second 40 sections is circular but may be designed as needed or desired to support need and function of the fabric. The weave pattern of both the first 38 and second 40 sections is also provided. The first section 38 of the fourth embodiment 36 has a 1,1 weave and the second section 40 has a 4,4 weave.

A further application of the present embodiments is for the creation of fabric scaffolding for cell in-growth. It is anticipated that by configuring fabrics of varied pore size, cell in-growth can be encouraged. As a result, a fabric scaffold may be designed to encourage growth of particular cells by size and thus location on or in the fabric scaffold.

It should also be appreciated that the knit patterns shown herein are linear in shape, having a straight length and width. However, applicant anticipates that the embodiments described above could also be created by knitting to the desired size or width of the particular application. For example, if a resulting piece was desired to have a diamond shape, that shape may be achieved either by cutting that shape into a sheet of fabric, or by knitting the piece to the desired shape. If the piece were being knitted, the knit pattern would need to include tapered sections to create the diamond shape. It will be appreciated that any number of linear and curved shapes may be achieved and that the diamond is an example and in no way intended to limit the scope of the embodiments described herein.

Applicant further notes that there is at least one alternative method for creating the embodiments disclosed herein. Instead of varying the stitch pattern to create a fabric having varied number of interlacings, an alternative method is to apply tension to an area of fewer nodal points and subsequently heat treat the fabric. The area under tension will maintain its density while the remaining fabric will shrink or retract, thus creating a higher number of nodal points or interlacings. This method can be applied to the variety of embodiments described above.

As used herein, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, the term “a yarn” or “a pore” is intended to mean a single yarn or a single pore, or more than one yarn or pore. Furthermore, uses within the specification of terms such as “upper,” “lower,” “vertical,” “horizontal,” and the like are words of convenience used to describe the structure and function of the parts of the embodiments herein relative to each other and are not meant in any way to be construed as limiting terms.

Claims

1. A fabric comprising:

a first fabric section comprising first fabric pores created by first interlacings of yarn in a first pattern, and having a first average pore size;

a second fabric section having second fabric pores created by second interlacings of yarn in a second pattern, and a second average pore size, wherein the number of first interlacings of yarn is greater than the number of second interlacings of yarn; and

an interface created between the first fabric section and the second fabric section,

whereby the first interlacings enhance the strength of the second fabric section and reduce the potential for fray.

2. The fabric of claim 1 wherein the first fabric section surrounds the second fabric section.

3. The fabric of claim 1 wherein the first average pore size is at least 100% smaller than the second average pore size.

4. The fabric of claim 1 wherein the weight of the first fabric section is at least 50% greater than the weight of the second fabric section.

5. The fabric of claim 1 wherein the thickness of the first fabric section is at least 10% greater than the thickness of the second fabric section.

6. The fabric of claim 1 wherein the burst strength of the first fabric section is at least 50% greater than the burst strength of the second fabric section.

7. The fabric of claim 1 wherein the number of first interlacings is at least 50% more than the number of second interlacings.

8. The fabric of claim 1 wherein the percentage of open area of the first fabric section is about 7% less than the percentage of open area of the second section.

9. The fabric of claim 1 wherein the fabric is knit.

10. The fabric of claim 1 wherein the fabric is woven.

11. A method of creating a reinforced mesh fabric, comprising the steps of:

creating a first fabric section having first fabric pores created by first interlacings of yarn in a first pattern, and having a first average pore size;

creating a second fabric section having second fabric pores created by second interlacings of yarn in a second pattern, and a second average pore size, wherein the number of first interlacings of yarn is greater than the number of second interlacings of yarn;

whereby the first interlacings enhance the strength of the second fabric section and reduce the potential for fray.

12. The method of claim 11 wherein the first fabric section surrounds the second fabric section.

13. The method of claim 11 wherein the difference in average pore size between the first average pore size and the second average pore size is at least 100%.

14. The method of claim 11 wherein the difference in weight between the first and second fabric sections is at least 50%.

15. The method of claim 11 wherein the difference in thickness between the first and second fabrics is at least 10%.

16. The method of claim 11 wherein the burst strength between the first and second fabric sections is at least 50%.

17. The method of claim 11 wherein the number of first interlacings is at least 50% more than the number of second interlacings.

18. The method of claim 11 wherein the percentage of open area of the first fabric section is about 7% less than the percentage of open area of the second section.

19. The method of claim 11 wherein the first and second fabric sections are knit.

20. The method of claim 11 wherein the first and second fabric sections are woven.