阅读说明：本技术 覆膜结构、覆膜管、覆膜管制备方法及覆膜支架 (Film covering structure, film covering pipe preparation method and film covering stent ) 是由 马晓曼 胡冰清 张静 宗雪 阙亦云 于 2019-11-01 设计创作，主要内容包括：本发明公开了一种覆膜结构、覆膜管、覆膜管制备方法及覆膜支架。该覆膜结构包括由第一编织结构和第二编织结构,第二编织结构与第一编织结构共同形成所述覆膜结构,第二编织结构穿插于第一编织结构并与第一编织结构相连接,第二编织结构的密度低于第一编织结构的密度。覆膜管包括由覆膜结构形成的管体。本发明实施例还提供了一种覆膜管的制备方法。本发明实施例提供的覆膜结构、覆膜管以及覆膜管制备方法能够有效解决现有技术中编织疵点的出现,提高合格率,降低覆膜管成本。(The invention discloses a film covering structure, a film covering pipe, a preparation method of the film covering pipe and a film covering stent. The film covering structure comprises a first weaving structure and a second weaving structure, wherein the second weaving structure and the first weaving structure jointly form the film covering structure, the second weaving structure is inserted into the first weaving structure and connected with the first weaving structure, and the density of the second weaving structure is lower than that of the first weaving structure. The coated tube includes a tube body formed of a coated structure. The embodiment of the invention also provides a preparation method of the film-coated tube. The film coating structure, the film coating pipe and the preparation method of the film coating pipe provided by the embodiment of the invention can effectively solve the problem of weaving defects in the prior art, improve the qualification rate and reduce the cost of the film coating pipe.)

1. A film covering structure comprises a first woven structure and is characterized by further comprising a second woven structure, the second woven structure and the first woven structure jointly form the film covering structure, the second woven structure is inserted into the first woven structure and connected with the first woven structure, and the density of the second woven structure is lower than that of the first woven structure.

2. The film covering structure of claim 1, wherein the film covering structure is woven from warp yarns and weft yarns, and the second woven structure extends in the warp direction.

3. The film structure of claim 1 or 2, wherein the number of the second woven structures is two or more, and adjacent second woven structures are arranged in parallel and spaced apart.

4. The film structure of claim 3, wherein the spacing between adjacent second braided structures is 3mm to 6 mm.

5. The film covering structure according to claim 1 or 2, wherein the first weave structure is a plain weave structure; the second weave structure is a warp rib weave structure and/or a twill weave structure.

6. A coated pipe comprising a pipe body formed of the coating structure according to any one of claims 1 to 5.

7. The coated tube of claim 6, wherein the coated structure is sewn into a tubular shape to form the tubular body.

8. The coated tube of claim 6, wherein the coated structure is formed into a tubular shape by an integral braiding process to form the tube body.

9. The coated tube of claim 6, wherein the tube body has at least a first and a second tube segment connected to each other, the first tube segment having a diameter greater than a diameter of the second tube segment, at least a portion of the second braided structure being disposed on the second tube segment.

10. The coated tube of claim 9, wherein the second tube segment has a connection end connected to the first tube segment and a free end opposite the connection end, the portion of the second braided structure disposed on the second tube segment extending from the connection end to the free end.

11. The film-coated pipe according to any one of claim 10, wherein the first pipe section is cylindrical, and the second braided structure is entirely disposed on the second pipe section; or, the first tube section comprises a frustum-shaped transition tube section, and a part of the second weaving structure is arranged on the frustum-shaped transition tube section, extends to the connecting end of the second tube section, and is connected with a part of the second weaving structure arranged on the second tube section.

12. The film-coated pipe according to any one of claims 9 to 11, wherein the pipe body comprises a main pipe section and at least two branch pipe sections, each branch pipe section is connected with one end of the main pipe section to form an integral structure and is communicated with the main pipe section, at least one branch pipe section is the second pipe section, and the main pipe section is the first pipe body.

13. The coated tube of claim 12, wherein the second braided structure extends axially along the bifurcated segment.

14. The coated tube of claim 12, wherein the tube body has at least two second tube segments, and wherein at least two of the branch tube segments are both the second tube segments.

15. A preparation method of a coated pipe is characterized by comprising the following steps:

weaving a first woven structure and a second woven structure by using weft yarns and warp yarns to jointly form a tube body of the film-covered tube, and enabling the second woven structure to be inserted into the first woven structure and connected with the first woven structure, wherein the density of the second woven structure is lower than that of the first woven structure.

16. The method of manufacturing a coated pipe according to claim 15, further comprising: when weaving the second woven structure, the second woven structure is caused to extend in the direction of the warp yarns.

17. The method of claim 15, wherein the step of weaving the first woven structure and the second woven structure with weft yarns and warp yarns to collectively form the tube body of the coated tube further comprises: weaving a portion of the first woven structure and a portion of the second woven structure with the weft yarns and the warp yarns to form a first section of the coated pipe, and continuing to weave another portion of the first woven structure and the second woven structure with the weft yarns and the warp yarns to form at least one second section of the coated pipe, wherein the first section has a diameter greater than a diameter of the second section.

18. The method of claim 17, wherein the step of weaving a portion of the first woven structure and a portion of the second woven structure with the warp yarns using the weft yarns to form the first section of the coated tube further comprises: weaving a portion of the first woven structure with the weft yarns and the warp yarns to form a portion of the first tube section, and continuing to weave another portion of the first woven structure and the second woven structure with the weft yarns and the warp yarns to form a frustum-shaped transition tube section of the first tube section.

19. The method of claim 15, wherein the step of weaving the first woven structure and the second woven structure with weft yarns and warp yarns to collectively form the tube body of the coated tube further comprises: weaving a part of the first woven structure by using the weft yarns and the warp yarns to form a cylindrical first pipe section of the film covering pipe, and continuously weaving another part of the first woven structure and the second woven structure by using the weft yarns and the warp yarns to form at least one second pipe section of the film covering pipe, wherein the diameter of the first pipe section is larger than that of the second pipe section.

20. The method of manufacturing a coated tube according to claim 15, wherein the first woven structure and the second woven structure are woven by using weft yarns and warp yarns through an integral weaving molding process and a tube body of the coated tube is directly formed.

21. A stent graft comprising the stent graft of any one of claims 6 to 14 and a stent body, wherein the stent graft is wrapped around an outer surface of the stent body.

Technical Field

The invention relates to the field of medical instruments, in particular to a covered membrane structure, a covered membrane tube preparation method and a covered stent which can be used for treating intravascular diseases.

Background

In the medical field, stent grafts have become the mainstream products of artificial blood vessels in recent years, and mainly treat diseases such as aneurysms and arterial dissections. The covered stent consists of a covering film and a metal stent, and the covering film mainly plays a role in blood blocking. The covering film of the covered stent is generally formed by sewing a planar film into a tubular film and then coating a metal stent.

At present, a film covering pipe usually adopts a woven plain weave structure, the good hypotonic blood volume is achieved, besides the form of the weave structure, the weave structure is also related to the density of warp density and weft density, the warp density is generally required to reach 150-, the generation rate of the defects also becomes high, and the defects directly influence the blood seepage and the strength of the covered stent, so that the probability of high-risk medical accidents is increased.

With the progress of textile technology, the integrally formed tubular film is more and more accepted by the medical appliance industry, and the performance advantages are shown as follows: the integrally formed tubular membrane avoids the existence of seam joints, saves working hours for manufacturing the covered stent, and has uniform water seepage and stable strength; the integrated into one piece tectorial membrane pipe does not have the seam, the thickness of tectorial membrane pipe has been reduced, make the entering sheath size of tectorial membrane support diminish, improve the unobstructed rate of operation process, and to current integrated into one piece tectorial membrane pipe weaving technique, because need an organic whole to weave and form, if the condition that the body radial dimension diminishes appears, if the body is the spinal canal, bifurcated pipe or irregular pipe etc. more easily because warp density grow in the twinkling of an eye, directly lead to warp tension and/or woof tension grow, and tension grow, yarn fracture risk can improve, yarn in case fracture, the fabric surface will form the defect that influences the tectorial membrane performance, directly influence body intensity and infiltration volume, therefore the integrated into one piece tectorial membrane pipe among the prior art's the knit qualification rate is low, and is with high costs, be difficult to popularize and use, become the development bottleneck of this technique.

Disclosure of Invention

Accordingly, there is a need for a covered stent, a covered stent structure, a covered stent manufacturing method and a covered stent, which can effectively solve one or more technical problems in the prior art, improve the weaving yield of the covered stent and reduce the manufacturing cost of the covered stent.

The invention provides a film covering structure which comprises a first weaving structure and a second weaving structure, wherein the second weaving structure and the first weaving structure jointly form the film covering structure, the second weaving structure is inserted into the first weaving structure and connected with the first weaving structure, and the density of the second weaving structure is lower than that of the first weaving structure.

In one embodiment, the film covering structure is woven from warp and weft yarns, and the second woven structure extends in the warp direction.

In one embodiment, the number of the second weaving structures is two or more, and the adjacent second weaving structures are arranged in parallel with a gap therebetween.

In one embodiment, the spacing between adjacent second braided structures is 3mm to 6 mm.

In one embodiment, the first weave structure is a plain weave structure; the second weave structure is a warp rib weave structure and/or a twill weave structure.

The invention also provides a coated pipe which comprises a pipe body formed by any one of the coating structures.

In one embodiment, the film structure is sewn into a tubular shape to form the tubular body.

In one embodiment, the film structure is made into a tubular shape by an integral weaving forming process, so as to form the tube body.

In one embodiment, the tubular body has at least a first tubular section and a second tubular section connected to each other, the first tubular section having a diameter greater than a diameter of the second tubular section, and at least a portion of the second braided structure is disposed in the second tubular section.

In one embodiment, the second tube segment has a connecting end connected to the first tube segment and a free end opposite the connecting end, and the second braided structure is disposed in a portion of the second tube segment extending from the connecting end to the free end.

In one embodiment, the first tube section is cylindrical, and the second braided structure is completely arranged on the second tube section; or the first pipe section comprises a frustum-shaped transition pipe section, and the other part of the second weaving structure is arranged on the frustum-shaped transition pipe section, extends to the connecting end of the second pipe section, and is connected with the part of the second weaving structure arranged on the second pipe section.

In one embodiment, the pipe body includes a main pipe section and at least two branch pipe sections, each branch pipe section is connected with one end of the main pipe section to form an integrated structure and is communicated with the main pipe section, at least one branch pipe section is the second pipe section, and the main pipe section includes the first pipe body.

In one embodiment, the second braided structure extends in an axial direction of the bifurcated segment.

In one embodiment, the pipe body has at least two second pipe sections, and at least two of the branch pipe sections are both the second pipe sections.

The invention provides a preparation method of a coated pipe, which comprises the following steps:

weaving a first woven structure and a second woven structure by using weft yarns and warp yarns to jointly form a tube body of the film-covered tube, and enabling the second woven structure to be inserted into the first woven structure and connected with the first woven structure, wherein the density of the second woven structure is lower than that of the first woven structure.

In one embodiment, the second weaving structure is woven such that it extends in the direction of the warp yarns.

In one embodiment, the method comprises the following steps:

the step of weaving the first woven structure and the second woven structure with weft yarns and warp yarns to collectively form the tube body of the film-covered tube further comprises: weaving a portion of the first woven structure and a portion of the second woven structure with the weft yarns and the warp yarns to form a first section of the coated pipe, and continuing to weave another portion of the first woven structure and the second woven structure with the weft yarns and the warp yarns to form at least one second section of the coated pipe, wherein the first section has a diameter greater than a diameter of the second section.

In one embodiment, the step of weaving a portion of the first woven structure and a portion of the second woven structure with the warp yarns using the weft yarns to form the first section of the coated pipe further comprises: weaving a portion of the first woven structure with the weft yarns and the warp yarns to form a portion of the first tube section, and continuing to weave another portion of the first woven structure and the second woven structure with the weft yarns and the warp yarns to form a frustum-shaped transition tube section of the first tube section.

In one embodiment, the step of weaving the first woven structure and the second woven structure with weft yarns and warp yarns to collectively form the tube body of the film-covered tube further comprises: weaving a part of the first woven structure by using the weft yarns and the warp yarns to form a cylindrical first pipe section of the film covering pipe, and continuously weaving another part of the first woven structure and the second woven structure by using the weft yarns and the warp yarns to form at least one second pipe section of the film covering pipe, wherein the diameter of the first pipe section is larger than that of the second pipe section.

In one embodiment, the first woven structure and the second woven structure are woven by weft yarns and warp yarns through an integral weaving process and the tube body of the film covering tube is directly formed.

The invention provides a covered stent, which is characterized by comprising any one of the covered tubes and a stent main body, wherein the covered tube is covered on the outer surface of the stent main body.

The laminated tube structure can effectively solve the problem that defects are easily generated due to overlarge warp density in the weaving process of the existing laminated tube, and improve the yield of the laminated tube structure.

The invention sets a second weaving structure design for solving the problem of fabric defects in the weaving process, locally reduces the yarn density and prevents the defects; the design can ensure that the weaving is smooth and avoid the defect of fabric defects, can ensure the effective thickness and the water seepage function of the fabric, effectively avoids the occurrence of weaving defects, improves the qualification rate of finished product weaving, and reduces the cost of the structure of the coated pipe.

Drawings

FIG. 1 is a schematic view of a membrane-covered tube structure according to an embodiment of the present invention;

FIG. 2 is a schematic view of a lamination tube structure according to another embodiment of the present invention;

FIG. 3 is a schematic view of a lamination tube configuration according to another embodiment of the present invention;

FIG. 4 is a schematic view of a plain weave construction;

FIG. 5 is a schematic view of a flattened tissue structure.

Description of the reference numerals

10: a tectorial membrane tube structure;

100: a pipe body;

200: a main pipe section;

210: a first braided structure;

300: a branch pipe section;

310: a second braided structure;

400: a bifurcation location;

500: a transition duct section.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "coated" on another element, it can be directly coated on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. When an element is referred to as being "woven" into another element, it can be directly woven into the other element or intervening elements may also be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The first embodiment of the invention provides a film covering structure which comprises a first weaving structure and a second weaving structure, wherein the second weaving structure and the first weaving structure jointly form the film covering structure, the second weaving structure is inserted into the first weaving structure and connected with the first weaving structure, and the density of the second weaving structure is lower than that of the first weaving structure.

Further, the film structure provided by this embodiment is woven by warp yarns and weft yarns, and the second woven structure is inserted into the first woven structure and extends along the warp direction, thereby forming the film structure of this embodiment. Preferably, the number of the second weaving structures is two or more, the adjacent second weaving structures are arranged in parallel at intervals, and the interval between the two adjacent second weaving structures is 3mm-6 mm. In the present embodiment, the first weave structure is a plain weave structure; the second weave structure is a warp rib weave structure and/or a twill weave structure.

In a second embodiment, the invention provides a covered tube, which includes a tube body formed by the covered structure in the first embodiment, and the covered tube provided by the embodiment is suitable for covering the outer surface of the stent main body to form a covered stent.

As shown in fig. 1 to 3, the tubular body of the coated tube in the embodiment of the present invention is formed by a tubular coated structure formed by an integral knitting molding process. In another embodiment, the body of the coated tube 10 may be manufactured as follows: the sheet-like film structure is formed first, and then the sheet-like film structure is connected to form a tube body, for example, the film structure is sewn into the tube body of the film tube 10 by sewing.

In the present embodiment, a tubular body integrally knitted and formed by a film structure will be described as an example. Specifically, the coated tube 10 includes a tube body 100 woven from a first woven structure 210 and a second woven structure 310, the second woven structure 310 being inserted into the first woven structure 210 and connected to the first woven structure 210, the second woven structure 310 having a density lower than that of the first woven structure 210. Preferably, the second weaving structure 310 extends along the axial direction of the tube 100, i.e., the warp direction.

Further, the number of the second weaving structures 310 is two or more. There is a space between two adjacent second braided structures 310. Preferably, the interval between two adjacent second braided structures 310 is 3mm to 6 mm. For example, the spacing between two adjacent second braided structures 310 is 3mm, 4mm, 5mm, 6mm or other non-integer value. The interval between two adjacent second weaving structures 310 can also be designed to be different according to the requirement of the fabric performance in actual weaving. During the actual weaving process, the interval between two adjacent second weaving structures 310 may be set according to the number of warp yarns in the first weaving structure 210; for example, one or more warp yarns for weaving the first woven structure 210 may be spaced between two adjacent second woven structures 310.

Preferably, as shown in fig. 1 or fig. 2, the plurality of second weaving structures 310 are arranged in parallel along the axial direction of the tube 100 and are uniformly distributed on the circumferential surface of the tube 100, and the interval between each two adjacent second weaving structures 310 is equal, which can uniformly reduce the density of the tube 100 and simultaneously reduce the weaving difficulty of the tube 100.

Further, the first weave structure 210 is a plain weave structure, and the second weave structure 310 is a warp rib weave structure and/or a twill weave structure. It should be noted that the plain weave structure is such that the warp and weft yarns are woven in a floating and sinking relationship with each other (as shown in fig. 4). The warp-rib structure is a rib structure (as shown in fig. 5) in which a plain weave is used as a base weave and a weave point is extended in the warp direction. The twill weave structure is only one warp structure point on each yarn, and all the others are weft structure points, or only one weft structure point, all the others are warp structure points, and are collectively called as twill weave structure. Since the weave density of the warp rib weave structure and/or the twill weave structure is lower than that of the plain weave structure, the present embodiment utilizes the design of the plain weave structure and the warp rib weave structure and/or the twill weave structure in an alternating manner, and reduces the probability of the occurrence of defects on the fabric surface of the film covered tube structure 10 by reducing the local density of the fabric of the film covered tube structure 10.

Preferably, a warp-heavy plain weave structure and/or a twill weave structure formed by weaving 1-2 warps and wefts can be selected, so that the increase of water seepage is avoided on the premise of ensuring the reduction of defects.

The following are three implementation manners of the film-coated tube 10 provided by the embodiment of the present invention, specifically as follows:

in a first implementation, as shown in fig. 1, the tubular body 100 has at least a first tubular segment 200 and a second tubular segment 300 connected to each other, the first tubular segment 200 has a diameter larger than a diameter of the second tubular segment 300, and at least a portion of the second braided structure 310 is disposed on the second tubular segment 300. The first pipe segment 200 includes a tapered transition pipe segment 500, and both ends of the tapered transition pipe segment 500 are respectively connected with the second pipe segment 300 and the other cylindrical portion of the first pipe segment 200.

The radial dimension of first tube segment 200 varies from transition tube segment 500. Since the change in the radial dimension of the tubular body 100 is a gradual change in the radial dimension of the tubular body, it can be appreciated that the second braided structure 310 can be positioned from a location where the transition segment begins or ends. When the second braided structure 310 is disposed from the location where the transition tube segment begins, the second braided structure 310 is disposed on both the first tube segment and the second tube segment, i.e., at least a portion of the second braided structure 310 is disposed on the second tube segment and another portion is disposed on the first tube segment, and the portion of the second braided structure 310 disposed on the second tube segment 300 is connected to another portion of the second braided structure 310 disposed on the first tube segment.

The location where transition section 500 ends may be considered the coupled end where second section 300 is coupled to first section 200, second section 300 also includes a free end opposite the coupled end, and second braided structure 310 may also be positioned from the location where transition section 500 ends, second braided structure 310 extending from the coupled end to the free end of second section 300. It is understood that, since the integrated knitting process is that the knitting machine is controlled by the computer control program to automatically perform the knitting process, in practice, due to the problems of machine control accuracy and the like, the starting position of the second knitting structure 310 in the actual product may deviate from the predetermined position within a reasonable error range, for example, the second knitting structure 310 extends from the vicinity (upper and lower 3-5 mm) of the connecting end of the second tube segment 300 to the free end of the second tube segment 300, which should also be regarded as the second knitting structure 310 extends from the connecting end to the free end of the second tube segment 300.

As shown in fig. 1, in this embodiment, the second braided structure 310 extends from between the start and end positions of the transition tube segment 500 to the free end of the second tube segment 300.

In the tube weaving process, the warp density is changed suddenly due to the change of the tube diameter, which increases the risk of defects, so that the starting position and the ending position of the transition tube section 500 are both positions where defects start to be generated in large quantity, and the probability of defects being generated is higher from the starting position of the transition tube section 500 to the ending position of the transition tube section 500 due to the fact that the warp threads are further dense, and therefore, the second weaving structure 310 preferably extends from the starting position of the transition tube section 500 to the free end of the second tube section 300, which can reduce the defects to the maximum extent, but it can be understood that the technical effect of reducing defects can be achieved by providing the second weaving structure 310 at any position.

It is understood that the second weave structure 310 may be disposed in the axial direction of the entire laminating pipe (i.e., from the free end of the first pipe section to the free end of the second pipe section), which may also reduce the defects to some extent, but the embodiment is not limited thereto.

The second implementation is substantially the same as the first implementation, and for the sake of brevity, only the differences will be described below, and as shown in fig. 2, the tube body 100 of the coated tube provided in the present embodiment includes a first tube segment 200 (i.e., a main tube segment) and two second tube segments 300 (i.e., branch tube segments), so as to form a bifurcated tube structure. The main pipe section and each branch pipe section all are cylindrical pipe, and each branch pipe section all is connected with the one end of main pipe section and is the integral type structure and with main pipe section intercommunication, and the second is woven structure 310 and is begun to extend along the axial of branch pipe section along the boundary position of branch pipe section and main pipe section, and second is woven structure 310 and is set up on two branch pipe sections.

Of course, in other embodiments, the second braided structure 310 may be disposed on only one branch tube segment or extend from the vicinity of the boundary position between the branch tube segment and the main tube segment along the axial direction of the branch tube segment, which also can achieve the technical effect of reducing the generation of defects, and the reasons have been already described in the first implementation manner and are not described herein again.

The third embodiment is substantially the same as the second embodiment, and for the sake of brevity, only the differences will be described below, and as shown in fig. 3, the first pipe body 200 further includes a transition pipe section 500 with a varying radial dimension, and the transition pipe section 500 is connected to and communicates with two second pipe sections 300 (i.e., branch pipe sections). It is understood that the second braided structure 310 may be disposed from the beginning of the transition section 500, from the end of the transition section 500, or from a position between the beginning and the end of the transition section 500, which is not limited in this embodiment.

In the coated pipe provided by the embodiment of the present invention, when the radial dimension of the pipe body 100 is reduced from one end to the other end, the second braided structure 310 is braided at the end with the smaller radial dimension, so that the fabric density of the original first braided structure 210 is reduced, the local yarn density is reduced, and the generation of defects is prevented. The weave at the radial dimension change position, i.e., the boundary position, of the tube body 100 is changed from a single plain weave to a plain weave structure in which a rib weave structure is uniformly inserted, so that the local density of the fabric of the film tube structure 10 is reduced, the density is reduced, the yarn tension is reduced, and the fabric on the film tube structure 10 is not easy to form defects in the weaving process.

The third embodiment of the invention also provides a preparation method of the coated pipe, which is used for preparing the coated pipe in the previous embodiment. The preparation method of the laminated tube structure comprises the following steps:

when the pipe body 100 is a non-bifurcated pipe structure having the transition pipe section 500 in the first implementation manner, the preparation method is as follows:

weaving the weft yarns with the warp yarns to form a part of the first woven structure 210 as a first tube segment, continuing to weave another part of the first woven structure 210 with the warp yarns and a second woven structure 310 inserted through the first woven structure 210 and connected to the first woven structure 210 to form a transition tube segment 500, continuing to weave another part of the first woven structure 210 with the warp yarns and another part of the second woven structure 310 as a second tube segment, the second woven structure 310 extending in the warp direction of the branch tube segment.

When the pipe body 100 is a bifurcated pipe structure without the transition pipe section 500 in the second implementation manner, the preparation method is as follows:

the method includes the steps of weaving a part of the first weaving structure 210 with weft yarns and warp yarns to form a main tube section, continuously weaving the other part of the first weaving structure 210 with the weft yarns and the warp yarns, and weaving the second weaving structure 310 inserted into the first weaving structure 210 and connected with the first weaving structure 210 to form two or more branch tube sections connected with and communicated with the main tube section, wherein the second weaving structure 310 extends along the warp yarn direction of the branch tube sections.

When the pipe body 100 is a bifurcated pipe structure having the transition pipe section 500 in the third implementation manner, the preparation method is as follows:

weaving a part of the first weaving structure 210 by the weft yarns and the warp yarns to form a part of the main tube section, continuously weaving the other part of the first weaving structure 210 by the weft yarns and the warp yarns and forming a transition tube section by the second weaving structure 310 which is inserted into the first weaving structure 210 and connected with the first weaving structure 210, continuously weaving the other part of the first weaving structure 210 and the other part of the second weaving structure 310 by the weft yarns and the warp yarns to form two or more branch tube sections which are connected with and communicated with the main tube section, and extending the second weaving structure 310 along the warp yarn direction of the branch tube sections.

Compared with the prior art, in the preparation method of the laminating pipe provided by the embodiment of the invention, because the density of the second weaving structure 310 is lower than that of the first weaving structure 210, the yarn density of the position of the second weaving structure 310 on the branch pipe section is relatively low, and the generation of defects during weaving can be prevented.

In a fourth embodiment of the present invention, a stent graft is provided, in which the stent graft 10 prepared by the method for preparing a stent graft in the third embodiment is coated on the outer surface of the stent body to form the stent graft.

The coated pipe provided by the embodiment has the advantage that the qualification rate is obviously improved on the basis of ensuring the existing tensile strength and water permeability.

The inventors measured the yield of the coated tube provided with the second braided structure 310 and without the second braided structure 310 through batch experiments when developing the coated tube of the bifurcated tube structure.

Then, 110 film-coated pipes in the prior art are selected for qualification rate detection, the diameter of a main pipe section of each film-coated pipe is 26mm, the length of each film-coated pipe is 120mm, the diameters of two branch pipe sections are 12mm and the lengths of the two branch pipe sections are 140mm respectively, namely the main pipe section comprises transition pipe sections of the branch pipe sections, the qualification rate is only 22.7%, and the unqualified reason is mainly defects; when the second weaving structure 310 (warp re-flattening formed by single warp yarn and multiple weft yarns) is arranged on the transition pipe section and the branch pipe section, the starting position of the second weaving structure 310 is located at the connecting end of the branch pipe section (basically, no error exists), the interval between two adjacent weaving structures is 30-60 yarns, the width is 3-6mm, and the applicant selects 110 yarns for testing, and then the qualification rate is increased to 86.67%.

Then 90 film-coated pipes in the prior art are selected for qualification rate detection, the diameter of a main pipe section of each film-coated pipe is 24mm, the length of each film-coated pipe is 120mm, the diameters of two branch pipe sections are 12mm and the lengths of the two branch pipe sections are 140mm respectively, namely the main pipe section does not comprise a transition pipe section with the branch pipe sections, the qualification rate is only 27.78%, and the unqualified reason is mainly defects; when the second weaving structure 310 (warp re-flattening formed by single warp yarn and multiple weft yarns) is arranged on the transition pipe section and the branch pipe section, the initial position of the second weaving structure 310 is located at the connecting end of the branch pipe section (basically, no error exists), the interval width of two adjacent weaving structures is 3-5mm, and the applicant selects 90 yarns to test, and then the qualification rate is increased to 87.50%.

In the aspect of water permeability, 2 coated tubes in the basic embodiment are selected immediately for qualification rate detection, the diameter of the main tube section of the coated tube is 26mm, the length of the coated tube is 120mm, the diameters of the two branch tube sections are 12mm and 140mm respectively, the starting position of the second weaving structure 310 (warp re-leveling formed by single warp and a plurality of weft) is positioned at the connecting end of the branch tube sections (basically, no error exists), the interval width of the two adjacent weaving structures is 3-5mm, and as a result, 1 coated tube is partially arranged on the first weaving structure 210The water seepage parameters are as follows: 113ml/cm²Min; the water permeability parameters of the diverging tube sections 300 of the mixed portion of the first braided structure 210 and the second braided structure 310 are: 115ml/cm²Min, the partial water permeability parameters of the first braided structure 210 of the other 1 coated tubes are: 109ml/cm²Min; the water permeability parameters of the branch pipe body 300 of the mixed portion of the first braided structure 210 and the second braided structure 310 are as follows: 103ml/cm²/min。

After the second weaving structure 310 is added to the film covering pipe in this embodiment of the detection data surface, the water permeability of the film covering pipe is not obviously affected, and the water permeability parameter of the branch pipe section of the film covering pipe is possibly smaller than the water permeability parameter of the main pipe body, which is mainly because the warp density of the branch pipe body is increased after the pipe diameter of the branch pipe body is reduced, so that the water permeability parameter of the first weaving mechanism on the branch pipe body is reduced, although the water permeability parameter of the branch pipe body can be increased by the second weaving structure 310 arranged on the branch pipe body, the water permeability parameter of the first weaving mechanism is reduced due to the increase of the total warp density, and after the total addition, the water permeability parameter of the branch pipe body is slightly smaller than the water permeability parameter of the main pipe body.

The stent covered with a membrane provided by the embodiment of the invention can effectively solve the problems of low qualification rate and many defects in the existing membrane covered tube weaving process, particularly the problem that in the integral weaving forming process, the defects are generated due to the fact that the fabric density changes along with the change of the fabric size when the radial size changes, the technical bottleneck that the defects are inevitable due to the change of the radial size of a tube body is solved, the membrane covered tube weaving qualification rate is improved, and the cost of the membrane covered tube is reduced. The design of the second weaving structure 310 is arranged at the local position of the woven fabric for solving the problem of fabric defects in the weaving process, so that the yarn density is locally reduced, and the defects are prevented; because the second weaving structure 310 is locally arranged, the design can ensure that weaving is smooth and avoids the defect of fabric defects, can ensure the effective thickness and the water seepage function of the fabric, avoids the problem that the thickness of the whole fabric is thickened and the water seepage caused by the thickening is increased, effectively solves the problem of weaving defects, improves the qualification rate of finished product weaving, and reduces the cost of the structure of the laminated tube.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.