Medical balloon, preparation method thereof and balloon catheter

Abstract

The invention discloses a medical balloon, a preparation method thereof and a balloon catheter, and relates to the technical field of balloon catheters.The medical balloon comprises a balloon body, the balloon body is provided with a balloon conical part, a reinforcing layer is arranged outside the balloon conical part, and the reinforcing layer is wrapped with a woven fiber layer; the diameter of the balloon body is larger than or equal to 8 mm, the cone angle alpha of the balloon cone part is larger than or equal to 30 degrees, and the average thickness value range of the reinforcing layer is 0.002-0.015 mm. The balloon catheter comprises the medical balloon. The pressure resistance of the balloon can be improved, the compliance of the balloon is reduced, and the balloon is safer to use.

Description

Technical Field

[0001] The present invention relates to the technical field of balloon catheters, and in particular to a medical balloon, a preparation method thereof, and a balloon catheter. Background Art

[0002] As a core tool in interventional therapy, balloon catheters are widely used in minimally invasive treatments for conditions such as coronary artery stenosis, peripheral vascular disease, valvular stenosis, and urinary tract stenosis. They physically dilate the lesion to restore lumen patency, offering minimal trauma and rapid recovery. When encountering difficult-to-dilate stenotic lesions, the balloon requires excellent pressure resistance and puncture resistance.

[0003] Although existing ordinary balloon catheters can play a therapeutic role in general diseases, due to their own compliance and low burst pressure limitations, they cannot expand the lesion site as required when high-pressure treatment is required. The lesion site will burst before it is fully expanded. Even if it is expanded, it will cause serious damage to the blood vessels and even aggravate the disease, making the use of balloon catheters less safe. Therefore, the demand for developing balloons with high burst pressure and low compliance is gradually increasing. Braided balloons, as a special functional balloon, can meet the above requirements very well, and because of their special surface structure, they can also resist calcification at the lesion site and reduce balloon explosions during expansion. However, due to the changes in the cone angle of the balloon, the braided fiber lines are prone to slippage and accumulation during the interweaving process of the balloon cone section, resulting in problems such as too low fiber weaving density or loose weaving, which in turn leads to reduced overall performance of the braided balloon. Summary of the Invention

[0004] The purpose of the present invention is to provide a medical balloon and a preparation method thereof, and a balloon catheter, so as to solve the problems existing in the above-mentioned prior art, improve the pressure resistance and make the use safer.

[0005] To achieve the above object, the present invention provides the following solutions: The present invention provides a medical balloon, comprising a balloon body, the balloon body having a balloon cone portion, a reinforcement layer provided on the outside of the balloon cone portion, and a woven fiber layer wrapped on the outside of the reinforcement layer; the diameter of the balloon body is greater than or equal to 8 mm, the cone angle α of the balloon cone portion is greater than or equal to 30°, and the average thickness of the reinforcement layer ranges from 0.002 to 0.015 mm.

[0006] In one embodiment, the reinforcement layer is a flexible resin coating, the braided fiber layer is wrapped with a fixing layer, and the fixing layer is a flexible resin coating.

[0007] In one embodiment, the reinforcement layer has polar groups and a surface that is an adhesive rough surface.

[0008] In one embodiment, the surface of the balloon cone has a rough surface structure, and the rough surface structure includes a frosted surface structure or a raised surface structure.

[0009] In one embodiment, a drug coating is provided within the mesh formed by the woven fiber layer.

[0010] In one embodiment, the woven fiber layer forms a radial limiting structure at the narrow neck of the balloon body, the reinforcement layer is provided on the balloon cone surface on both sides of the narrow neck of the balloon body, and the woven fiber layer is wrapped outside the reinforcement layer, and the woven fiber layer is wrapped outside the woven fiber layer.

[0011] The present invention provides a method for preparing a medical balloon, comprising the following steps: A rough surface structure is formed on the surface of the balloon cone by grinding or sandblasting, and then a flexible resin is coated on the balloon cone to form the reinforcement layer, and then the braided fiber layer is braided outside the reinforcement layer.

[0012] The present invention provides a method for preparing a medical balloon, comprising the following steps: Grooves or frosted structures are formed on the cavity wall corresponding to the balloon forming mold and the balloon cone, and the balloon material tube is blow-molded in the balloon forming mold to obtain the balloon body. A rough surface structure is formed on the surface of the balloon cone, and then a flexible resin is coated on the balloon cone to form the reinforcement layer, and then the woven fiber layer is woven outside the reinforcement layer.

[0013] The present invention provides a method for preparing a medical balloon, comprising the following steps: A dotted structure is injection molded on the surface of the balloon cone of the balloon material tube, and then blow molded to obtain the balloon body. A rough surface structure is formed on the surface of the balloon cone. A flexible resin is then coated on the balloon cone to form the reinforcement layer, and then the braided fiber layer is woven outside the reinforcement layer.

[0014] The present invention provides a balloon catheter comprising the above-mentioned medical balloon.

[0015] Compared with the prior art, the present invention has achieved the following technical effects: The present invention utilizes a reinforcing layer design to form stable interweaving points within the area of ​​the balloon's tapered portion where the diameter varies significantly. This prevents slippage of the braided fibers when the balloon's tapered angle is excessively large. This prevents the braided fiber layer from peeling off from the balloon, creating a sandwich layer. This reduces the pressure resistance of the balloon and prevents water from entering the braided fiber layer, thereby improving the safety of the balloon. If the braided fiber layer peels off from the balloon, forming a sandwich layer, water or blood could enter the sandwich layer during actual testing or use, further damaging the braided layer structure and causing poor performance of the braided balloon.

[0016] The reinforcing layer of the present invention has polar groups, which can form chemical bonds with the activated balloon cone and the activated woven fibers, forming physical and chemical dual fixation, thereby better fixing the woven fibers to prevent the woven fibers from slipping on the balloon cone.

[0017] The design of the rough surface structure of the balloon cone portion of the present invention can assist the reinforcing layer in providing support for the braided fibers during the braiding process, prevent the fibers from slipping, and further improve the stability of the braided fiber layer.

[0018] Through the combined effects of the roughened surface structure of the balloon cone, the reinforcement layer, and the polar groups in the reinforcement layer, the present invention can form a uniform and stable woven fiber layer while maintaining a relatively small cone length and a relatively large angle. This does not affect the pressure resistance of the balloon and also allows for greater design flexibility for the balloon cone size. The small cone length, and therefore the overall balloon length, facilitates passage through tortuous blood vessels, further improving its cornering performance, avoiding puncture of the vessel wall due to excessive balloon length during cornering, and enhancing the balloon's safety.

[0019] The braided fiber layer of the present invention is evenly distributed on the surface of the balloon, which constrains the size of the balloon. After the balloon is filled, it has more precise diameter and length dimensions, thereby reducing tissue tearing caused by excessive expansion, avoiding vascular or tissue complications, and improving safety in use.

[0020] The woven fiber layer on the surface of the balloon of the present invention can increase the friction of the balloon surface. During the actual treatment process, the balloon can be better fixed to the part to be treated, preventing the balloon from sliding during the operation and avoiding damage to surrounding tissues caused by the sliding of the balloon. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 Schematic diagram of the structure of a medical balloon in an embodiment of the present invention; Figure 2 1 is a schematic cross-sectional view of the cone portion of a medical balloon in an embodiment of the present invention; Figure 3 Schematic diagram of a balloon cone having a frosted surface structure in an embodiment of the present invention; Figure 4 Schematic diagram of a balloon cone having a convex surface structure in an embodiment of the present invention; Figure 5 Schematic diagram of a frosted structure formed on the cavity wall corresponding to the balloon forming mold and the balloon cone portion in an embodiment of the present invention; Figure 6 Schematic diagram of a groove structure formed on the cavity wall corresponding to the balloon forming mold and the balloon cone portion in an embodiment of the present invention; Figure 7 Schematic diagram of a balloon with a small cone angle in an embodiment of the present invention; Figure 8 Schematic diagram of a balloon with a large cone angle in an embodiment of the present invention; Figure 9 Schematic diagram of a medical balloon in a stepped shape according to an embodiment of the present invention; Figure 10 Schematic diagram of a straight medical balloon according to an embodiment of the present invention; Figure 11 Schematic diagram of a gourd-shaped medical balloon in an embodiment of the present invention; Figure 12 This is a schematic diagram of a braided fiber layer forming a radial limiting structure at the narrow neck of the balloon body in an embodiment of the present invention; Figure 13 for Figure 12 A partial enlarged schematic diagram of part A; Figure 14 This is a partial schematic diagram of a medical balloon with drug delivery in a braided density according to an embodiment of the present invention; Figure 15 This is a partial schematic diagram of a drug-carrying medical balloon of another weaving density according to an embodiment of the present invention; Figure 16 Schematic diagram of the structure of a balloon catheter in an embodiment of the present invention; Figure 17 This is a production process flow chart of a balloon catheter in an embodiment of the present invention; Figure 18 Schematic diagram of the generation of polar groups after balloon surface activation in an embodiment of the present invention; Figure 19 Schematic diagram of polar groups generated after fiber surface activation in an embodiment of the present invention; Figure 20 Schematic diagram of the chemical bond between the activated balloon and the reinforcement layer in an embodiment of the present invention; Figure 21 Schematic diagram of the chemical bonding between the activated fiber and the reinforcement layer in an embodiment of the present invention; Figure 22 This is a pattern diagram of woven fibers in an embodiment of the present invention; Figure 23 Schematic diagram of the pits formed on the balloon and fiber surfaces when applying glue; Figure 24This is a schematic diagram of the uneven glue distribution when the balloon surface is not treated; Figure 25 This is a schematic diagram showing the decrease in glue viscosity or the uniform distribution of glue after the balloon has been activated; Figure 26 Schematic diagram of spraying uniform glue atomized particles on the balloon surface to form a uniform and smooth glue layer; Figure 27 Schematic diagram of spraying uneven glue atomized particles on the balloon surface to form an uneven glue layer; Figure 28 This is a comparison chart of the bursting pressure of a medical balloon (8 mm) and an ordinary bare balloon (8 mm) in an embodiment of the present invention; Figure 29 This is a diagram comparing the compliance of a medical balloon (8 mm) and an ordinary bare balloon (8 mm) in an embodiment of the present invention; Figure 30 Schematic diagram showing uneven braiding density and braided fiber slippage when braiding the untreated balloon body cone; Figure 31 Schematic diagram of a medical balloon with uniform braiding density, no slippage of braided fibers, and uniform anisotropy when braiding the treated cone portion of the balloon body according to an embodiment of the present invention; Figure 32 This is a schematic diagram of the straight section structure of a medical balloon in an embodiment of the present invention; Figure 33 Schematic diagram of the cone structure of a medical balloon in an embodiment of the present invention; Figure 34 This is an angiographic image of the filling experiment of the medical balloon of the present invention in an animal experiment; Figure 35 This is an animal heart anatomy diagram after animal experiments using the medical balloon of the present invention.

[0023] In the figure: 1-balloon body, 2-balloon cone, 3-surface rough structure, 4-reinforcement layer, 5-woven fiber layer, 6-fixing layer, 7-balloon molding mold, 8-groove, 9-frosted structure, 10-catheter, 11-catheter end, 12-catheter seat, 13-drug coating, 14-balloon cone, 15-pit, 16-nozzle, 17-glue atomized particles, 18-activation equipment, 19-fiber interweaving point, 510-first weft, 520-warp, 530-second weft, 201-first cone, 202-second cone, 203-third cone, 204-fourth cone, 205-fifth cone, 206-sixth cone, 207-seventh cone. DETAILED DESCRIPTION

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0025] The purpose of the present invention is to provide a medical balloon and a preparation method thereof, and a balloon catheter, so as to solve the problems existing in the prior art, improve the pressure resistance and make the use safer.

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] Research on the problem of woven fiber slippage caused by excessively large balloon cone angles has found that the essence of the problem is the imbalance between geometric deformation and interfacial stress. The details are as follows: (1) Tension redistribution caused by geometric deformation. Specifically, the cone angle α (e.g. Figure 7 and Figure 8 As the taper angle (α) increases, the actual path length of the braided fiber in this region increases (i.e., the relationship between taper angle and fiber curvature). A larger taper angle requires a larger braiding angle, which results in a sharp increase in local tension from a small diameter (the balloon tube) to a large diameter (the balloon taper). This increases the tension exceeding the fiber-balloon interface bond, leading to fiber (thread) slippage along the tapered surface (i.e., tension imbalance). This geometric deformation-induced tension redistribution is particularly severe in balloons with diameters greater than 8 mm and taper angles greater than 30°.

[0028] (2) Interface shear stress concentration. Specifically, the slip driving force (F slide ): F slide ∝Tcosθ, (T is the fiber tension; θ is the tangential angle between the fiber and the cone); α increases → θ Decrease → cos θ Approaching 1 →‌ The sliding driving force is maximized. In other words, T cos θ It is the force against the fiber thread sliding down. The larger the braiding angle, T cos θThe smaller the value, the more difficult it is to resist slippage. Critical Angle Threshold: Based on weaving experience, for balloons with a taper angle α generally below 30°, the component of fiber tension T plus static friction can resist fiber slippage, and weave density can reach 90-100 PPI. However, when α exceeds the critical value of the material-structure (e.g., >30°), the slippage force exceeds the static friction force, resulting in collective fiber slippage. Interfacial shear stress concentration is particularly severe in balloons with a diameter greater than 8mm (or greater than 15mm) and a taper angle α greater than 30°.

[0029] (3) Excessive taper angles cause the fibers to experience a "tightly wound around a steep slope" state, with tension and geometric deformation synergistically triggering slippage. The chain reaction of failures caused by slippage is as follows: a. Initial slippage, with fibers partially detaching from the taper surface and interweaving points disintegrating → the braided layer structure loosens; b. Interlayer formation, expansion of the slip zone → balloon / braided layer peeling off, allowing water or blood to enter the interlayer; c. Performance degradation, with the medium eroding the interface and hydraulically expanding the interlayer, resulting in decreased pressure resistance and swelling / delamination of the braided layer; d. Final failure, with stress concentrated in the non-slipped area and a decrease in the balloon burst strength (in other words, the final failure is concentrated in the non-slipped area because the braiding density of the non-slipped braided area is low, perhaps only 5-20 PPI, which naturally reduces the balloon burst strength).

[0030] To this end, the present invention provides a medical balloon, such as Figure 1-Figure 2 As shown, it includes a balloon body 1 having a balloon cone 2, which is provided with a reinforcement layer 4 on the outside of the balloon cone 2, and the reinforcement layer 4 is wrapped with a woven fiber layer 5. The diameter of the balloon body 1 is greater than or equal to 8 mm, and the angle α of the balloon cone 2 is greater than or equal to 30 degrees. The thickness of the reinforcement layer 4 is less than that of the woven fiber layer 5. Furthermore, the woven fiber layer 5 does not directly contact the outer surface of the balloon cone 2 (that is, the woven fiber layer 5 is fixedly contacted with the reinforcement layer 4, and the reinforcement layer 4 is fixedly contacted with the outer surface of the balloon cone 2; in other words, the woven fiber layer 5, the reinforcement layer 4, and the balloon cone 2 are fixedly connected in sequence, forming a morphological structure in which the woven fiber layer 5 rests on the reinforcement layer 4). Furthermore, the average thickness of the reinforcement layer 4 ranges from 0.002 to 0.015 mm. Furthermore, the reinforcing layer 4 is a flexible resin coating layer; it can be understood that: a flexible resin is coated on the outer surface of the balloon cone 2 to form a soft pillow effect (pillow effect), supporting the braided wire and preventing the braided wire from slipping; the three-dimensional stress field is reconstructed, and the flexible resin coating layer produces elastic deformation under the action of the fiber tension T, converting point contact into surface contact, so that the contact area between the warp or weft and the flexible resin coating layer (reinforcing layer 4) is increased; on the one hand, the interface friction between the warp (or weft) and the flexible resin coating layer is enhanced, and on the other hand, the fiber interwoven node network of the woven fiber layer 5 disperses the local tension to the entire cone surface, avoiding single-point slip caused by stress concentration.

[0031] In some embodiments, the reinforcing layer 4 is a flexible resin coating, which can be made of TPU resin solution, polyacrylate glue, polyurethane glue, silicone glue, etc., or a combination of resin solution and glue. The mass ratio of the two can be between 1%-10%, and the viscosity can be between 1-10 Pa.s. It is formed on the surface of the balloon by leaching or spraying.

[0032] In some embodiments, the thickness of the reinforcing layer 4 is less than the thickness of the woven fiber layer 5. Specifically, when the outer surface of the balloon body 1 is coated with a flexible resin to form the reinforcing layer 4, the average thickness of the reinforcing layer 4 is in the range of 0.001 to 1 mm. Furthermore, the average thickness is preferably in the range of 0.002 to 0.015 mm, or 0.002 to 0.05 mm, or 0.005 to 0.07 mm, or 0.05 to 0.1 mm, or 0.1 to 0.7 mm, or 0.5 to 1 mm. The average thickness of the reinforcing layer 4 may also be any value of 0.002 mm, 0.008 mm, 0.015 mm, 0.03 mm, 0.05 mm, 0.07 mm, 0.15 mm, 0.3 mm, 0.5 mm, 0.9 mm, or 1 mm. The yarn diameter of the woven fiber layer 5 can range from 5 to 150D (Denier, abbreviated as D, is a unit used in the textile industry to measure the fineness of fibers or yarns, and is part of a fixed-length measurement system), preferably from 10 to 100D. The yarn diameter of the woven fiber layer 5 can also range from 0.01 to 1 mm, preferably from 0.05 to 0.5 mm. It should be understood that the thickness of the woven fiber layer 5 refers to the distance from the side of the woven fiber layer 5 distal to the outer surface of the balloon body 1 to the side proximal to the outer surface of the balloon body 1 (i.e., the sum of the yarn diameters of the warp and weft yarns after stacking). For example, in a stacked area comprising a first weft yarn 510, a warp yarn 520, and a second weft yarn 530, if the first weft yarn 510 is submerged in the reinforcing layer 4 and the warp yarn 520 (or the second weft yarn 530) is not submerged in the reinforcing layer 4, the thickness of the reinforcing layer 4 is considered to be less than the thickness of the woven fiber layer 5. For example, in the stacked area containing the first weft 510, the warp 520, and the second weft 530, the thickness thereof is greater than the thickness of the reinforcing layer 4. This design helps to suppress the formation of bubble pits in the reinforcing layer 4, making the thickness of the reinforcing layer 4 continuous and uniform; thereby avoiding the formation of a sandwich layer due to delamination between the woven fiber layer and the balloon.

[0033] In some embodiments, the present invention provides a medical balloon comprising a balloon body 1 and a braided fiber layer 5; Figure 2As shown, the woven fiber layer 5 includes warp threads 520, a first weft thread 510, and a second weft thread 530. The warp threads 520 extend longitudinally (along the length direction of the balloon body 1 and parallel to the length direction of the balloon body 1) and are arranged / distributed / deployed circumferentially along the balloon body 1. The first weft thread 510 spirally extends circumferentially along the balloon body 1, with a portion of the thread body interposed between the balloon body 1 and the warp threads 520. The second weft thread 530 spirally extends circumferentially along the balloon body 1 in a direction opposite to that of the first weft thread 510, with a portion of the thread body interposed between the balloon body 1 and the warp threads 520. The second weft thread 530 is interposed between the outer surface of the balloon body 1 and the warp threads 520. The woven fiber layer 5 also includes a reinforcement layer 4, which is used to provide support for the first weft thread 510 and / or the second weft thread 530 to prevent the first weft thread 510 and / or the second weft thread 530 from unexpectedly slipping during weaving. The balloon body 1 has a balloon cone 2.

[0034] In some embodiments, the braided fiber layer 5 is coated with a fixing layer 6. This fixing layer 6 is a flexible resin coating that can be formed on the balloon surface using a TPU resin solution, polyacrylate glue, polyurethane glue, epoxy glue, or the like. Furthermore, the fixing layer 6, in addition to the reinforcement layer 4, can better secure the braided fiber layer 5 to the balloon surface, preventing relative slippage between the braided fiber layer 5 and the balloon.

[0035] Further, such as Figure 3-Figure 4 As shown, the surface of the balloon cone 2 has a surface roughness structure 3. The design of the surface roughness structure 3 increases the surface roughness of the balloon, provides support for the fibers during the weaving process, and prevents the fibers from slipping. The reinforcing layer 4 has a certain viscosity and is evenly coated on the surface of the balloon cone 2 to increase friction. The reinforcing layer 4 has polar groups, which act on the surface of the balloon body 1 and the woven fiber layer 5, so that intermolecular forces are formed between the reinforcing layer 4 and the balloon body 1, the woven fiber layer 5 and the fixing layer 6. The polar groups form chemical bonds after the reaction, which can provide support for the woven fibers and better fix the woven fibers to prevent the woven fibers from slipping on the balloon cone 2 during the weaving process. At the same time, it serves as a base to provide a transition for the connection between the balloon and the outer layer. The woven fiber layer 5 is used to limit the radial expansion of the balloon body and constrain the size of the balloon. The balloon has more precise diameter and length dimensions after filling.

[0036] In some embodiments, the braided fibers may be radial fibers or a combination of axial fibers and radial fibers. The radial fibers are fibers interwoven at a certain angle around the radial direction of the balloon, and the axial fibers are fibers distributed along the axial direction of the balloon. The material of the braided fibers may be polyphenylene phthalate, aromatic polyester, polyethylene, or nickel-titanium alloy, etc. On the basis of stable weaving, there is a great deal of room for combination adjustment of the material and wire diameter of the radial fibers or axial fibers. By selecting the appropriate material and wire diameter, the wall thickness of the balloon can be reduced while ensuring the performance of the balloon, making the balloon more flexible and facilitating the retraction and withdrawal of the balloon. A combination of fiber lines with a smaller wire diameter can be selected for balloon weaving, which reduces the overall wall thickness of the balloon, reduces the outer diameter, and increases the softness of the balloon, thereby improving the bending performance of the balloon.

[0037] In some embodiments, the rough surface structure 3 is a frosted surface structure or a raised surface structure. The frosted surface structure can be formed by processes such as grinding and sandblasting, while the raised surface structure can be formed by bonding a flexible resin such as TPU, Pebax, or silicone to the balloon surface. The raised surface structure can also be formed by forming raised glue dots by array glue injection, or by directly affixing the raised material to the balloon tube and then integrally forming the structure.

[0038] like Figure 14-15 As shown, in some embodiments, a drug coating 13 is provided within the mesh formed by the woven fiber layer 5. The woven fiber layer 5 forms a grid on the balloon surface, dividing the balloon into multiple regions. By adjusting the weaving density, a grid structure of varying sizes can be formed. Depending on the specific treatment needs, drugs can be distributed within specific grids for targeted drug delivery. The drugs can include paclitaxel, rapamycin, everolimus, α-reductase inhibitors, or any combination thereof.

[0039] like Figure 32 As shown, it is a schematic diagram of the structure of the straight section of the medical balloon of the present invention. In the figure, the warp 520, the first weft 510 and the second weft 530 are woven to form a woven fiber layer 5. The woven fiber layer 5 forms a grid with a drug coating 13, and the woven fibers form fiber interlacing points 19 during weaving.

[0040] like Figure 33 , which is a schematic diagram of the balloon cone structure of the medical balloon of the present invention, a thin reinforcement layer 4 is provided on the surface of the balloon cone 2, and woven fibers (warp 520, first weft 510 and second weft 530) are located on the reinforcement layer 4.

[0041] like Figure 11-13As shown, in some embodiments, a braided fiber layer 5 forms a radially restraining structure at the narrow neck of the balloon body 1, constraining the narrow neck and precisely controlling its dimensions. A reinforcement layer 4 is also provided on the balloon conical surface 14 on either side of the narrow neck of the balloon body 1. The reinforcement layer 4 is wrapped with a braided fiber layer 5, which is in turn wrapped with a fixing layer 6. This improves the stability of the braided fibers on the balloon conical surface 14 on either side of the narrow neck and prevents them from slipping.

[0042] like Figure 7-Figure 8 As shown, based on the support of the reinforcing layer 4 on the braided fibers, a stable braided mesh structure can be formed on the balloon when the angle of the balloon cone 2 is small or large, and the angle α of the balloon cone 2 can range from 30-70°.

[0043] like Figures 9-11 As shown, the braided fibers can cover the entire balloon surface from the proximal end to the distal end of the balloon, forming an interwoven network in different areas of the balloon. Ordinary balloons or special-shaped balloons can be integrally formed.

[0044] like Figure 9 As shown, the balloon cones 2 at both ends of the balloon body 1 have the same slope angle β1, which is greater than or equal to 15 degrees. The average thickness of the reinforcement layer 4 coated on the outer surface of the balloon cone 2 is in the range of 0.002 to 0.015 mm. The drug coating 13 is only deployed in part of the mesh of the woven fiber layer 5 on the straight section of the balloon body 1, that is, there is no drug coating in the woven fiber layer on the balloon cone 2. Figure 14 and Figure 15 As shown, several grids of the woven fiber layer 5 on the balloon body 1 are filled with drug coating 13 to form a drug coating area with graphic characteristics; that is, the balloon body 1 has two types of areas filled with drug coating 13 and not filled with drug coating 13.

[0045] like Figure 10 The balloon body 1 has balloon cones (first cone 201, second cone 202 and third cone 203) with different slope angle values ​​(β2, β3 and β4), and each slope angle is greater than or equal to 15°. Figure 11As shown, the balloon body 1 has balloon tapers (fourth taper 204, fifth taper 205, sixth taper 206, and seventh taper 207) with different slope angles (β5, β6, β7, and β8), each with a slope angle greater than or equal to 15°. The reinforcing layer 4 coated on the outer surface of the balloon taper 2 has an average thickness ranging from 0.001 to 1 mm; further, the average thickness preferably ranges from 0.002 to 0.015 mm, or 0.002 to 0.05 mm, or 0.005 to 0.07 mm, or 0.05 to 0.1 mm, or 0.1 to 0.7 mm, or 0.5 to 1 mm. The average thickness of the reinforcing layer 4 can also be any value of 0.002 mm, 0.008 mm, 0.015 mm, 0.03 mm, 0.05 mm, 0.07 mm, 0.15 mm, 0.3 mm, 0.5 mm, 0.9 mm, or 1 mm. The drug coating 13 is only disposed in a portion of the mesh of the woven fiber layer 5 on the straight section of the balloon body 1.

[0046] The medical balloon of the present invention can be prepared by the following method: A flexible resin is coated on the balloon body 1 to form a reinforcement layer 4 , and then a braided fiber layer 5 is braided outside the reinforcement layer 4 . Finally, a flexible resin is wrapped outside the braided fiber layer 5 to form a fixing layer 6 .

[0047] The medical balloon of the present invention can also be prepared by the following method: A rough surface structure 3 is formed on the surface of the balloon cone 2 by grinding or sandblasting, and then a flexible resin is coated on the balloon cone 2 to form a reinforcement layer 4, and then a woven fiber layer 5 is woven outside the reinforcement layer 4, and finally a flexible resin is wrapped outside the woven fiber layer 5 to form a fixing layer 6.

[0048] The medical balloon of the present invention can also be prepared by the following method: like Figure 5-Figure 6 As shown, a groove 8 or a frosted structure 9 is formed on the cavity wall corresponding to the balloon forming mold 7 and the balloon cone by mechanical processing, and the balloon material tube is blow-molded in the balloon forming mold 7 to obtain a balloon body 1, and a surface roughness structure 3 is formed on the surface of the balloon cone 2. Then, a flexible resin is coated on the balloon cone 2 to form a reinforcement layer 4, and then a woven fiber layer 5 is woven outside the reinforcement layer 4. Finally, a flexible resin is wrapped outside the woven fiber layer 5 to form a fixing layer 6.

[0049] The medical balloon of the present invention can also be prepared by the following method: A dotted structure is injection molded on the surface of the balloon cone of the balloon material tube, and then blow molded to obtain a balloon body 1. A surface roughness structure 3 is formed on the surface of the balloon cone 2. Then, a flexible resin is coated on the balloon cone 2 to form a reinforcement layer 4. Then, a woven fiber layer 5 is woven outside the reinforcement layer 4. Finally, a flexible resin is wrapped outside the woven fiber layer 5 to form a fixing layer 6.

[0050] Among them, the material of the balloon tube can be Pebax, PA, PET, etc.

[0051] like Figure 16-17 As shown, the present invention provides a balloon catheter, including the medical balloon described above, and also including a catheter 10 and a catheter end 11 connected to the medical balloon and a catheter seat 12 connected to the catheter 10. The connection method of the above-mentioned parts belongs to the conventional technology in this field and will not be repeated here.

[0052] When assembling the balloon catheter, the medical balloon is first prepared using the above-mentioned preparation method, and then the medical balloon is assembled with the catheter 10, the catheter end 11 and the catheter seat 12 to obtain the balloon catheter.

[0053] The medical balloon of the present invention is described in detail below through specific embodiments.

[0054] Example 1 The medical balloon includes a balloon body 1, which is formed by blow-molding a balloon tube in a balloon forming machine (balloon forming mold 7). After forming, the balloon body 1 undergoes a plasma activation treatment using a gas such as oxygen, nitrogen, air, or any combination thereof. The fiber yarn is also plasma activated before braiding using a gas such as oxygen, nitrogen, air, or any combination thereof.

[0055] like Figure 18-19 As shown, after the balloon body 1 and fiber strands undergo plasma activation treatment in activation device 18, a large number of polar groups are introduced onto their surfaces. Oxygen can introduce a large number of hydroxyl and carboxyl groups onto the material surface, while nitrogen can introduce a large number of amino groups. Furthermore, bombardment with gases such as oxygen and argon can clean the material surface and create a large number of microscopic recessed structures, thereby increasing the surface contact area.

[0056] The balloon body 1 is provided with a reinforcement layer 4 on the outside, with a thickness between 0.002-0.015mm. The reinforcement layer 4 is an extremely thin layer of flexible resin. The reinforcement layer 4 is formed by a resin solution. Flexible resins such as thermoplastic polyurethane, linear polyurethane, etc. can be dissolved in solvents such as toluene, acetone, dimethyl sulfoxide, tetrahydrofuran, dichloromethane, dimethylformamide, dimethylacetamide, etc., or can be mixed solutions thereof, such as a 1:1 mixture of tetrahydrofuran and toluene (mass ratio), or a 1:1 mixture of tetrahydrofuran and dichloromethane (mass ratio), or a 1:1 mixture of toluene and dichloromethane (mass ratio). Usually, the resin is dissolved in the solvent at a ratio of 1%-10% (mass ratio), and the dissolved resin solution is uniform and transparent. During production, the balloon body 1 is immersed in the resin solution for 5-20s, the balloon is taken out and dried in an environment of 50-70°C for 5-10min, and the reinforcement layer 4 is formed. Figure 20-21 As shown, the molded reinforcement layer 4 contains groups such as hydroxyl, isocyanate, ether, and ester, which form hydrogen bonds and chemical bonds with the hydroxyl groups in the activated woven fibers, thereby enhancing the interaction between interfaces and preventing slippage.

[0057] Example 2 The balloon body 1 is provided with a reinforcement layer 4, which is an oxygen-blocking photocurable adhesive mainly composed of polyurethane, acrylate, etc. The adhesive is applied to the surface of the balloon body 1 by quantitative spraying and is cured by LED ultraviolet light in the atmospheric environment. After curing, the adhesive in contact with the surface of the balloon body 1 forms a stable connection structure, and the adhesive portion exposed to the atmosphere is not completely cured, retains some prepolymers and monomers, and has a high viscosity. The activated fibers form chemical bonds and hydrogen bonds with groups such as hydroxyl groups, carboxyl groups, isocyanate groups, and carbon-carbon double bonds on the surface of the reinforcement layer 4. At the same time, the adhesive surface with a higher viscosity provides a certain amount of friction support, and the braided fibers can be well attached to the balloon surface.

[0058] Example 3 The balloon body 1 is externally provided with a reinforcement layer 4, which is a two-component adhesive system such as epoxy resin, acrylate, or polyurethane. This type of adhesive naturally cures in ambient air at room temperature. As the curing time increases, the cross-linked network formed within it becomes larger, and the adhesive viscosity increases accordingly. After activation, the fibers form hydrogen bonds and chemical bonds with the hydroxyl, epoxy, carboxyl, and isocyanate groups on the surface of the reinforcement layer 4. The high viscosity of the adhesive also provides good adhesion to the fibers.

[0059] Example 4 The medical balloon includes a balloon body 1, which is formed by blow-molding a balloon tube in a balloon forming machine (balloon forming mold 7). The balloon body 1 can be made of Pebax, PA, PET, or a blend of these materials. The diameter of the balloon body 1 ranges from 8 to 30 mm, with a wall thickness between 0.03 and 0.08 mm. A reinforcement layer 4 covers the surface of the balloon body 1 and can be evenly applied by spraying. The reinforcement layer 4 can be made of a TPU resin solution, polyacrylate glue, polyurethane glue, silicone glue, or a combination of resin solutions and glues. Depending on the material of the reinforcement layer 4, it can be cured naturally at room temperature or by UV light. After the reinforcement layer 4 is applied, it is braided with fibers. The fibers can be made of polyphenylene phthalate, aromatic polyester, polyethylene, or nickel-titanium alloy. The fibers are interwoven to form a uniform woven fiber layer on the balloon surface, with a weave density between 40 and 90 mesh. The braided balloon is bonded with a TPU resin solution, polyacrylate glue, polyurethane glue, or epoxy glue to secure the fibers to the balloon surface. The uniform distribution of the braided fiber layers on the balloon surface allows for an overall burst pressure of 60+ atm and a compliance of less than 1%.

[0060] If the balloon is not treated in any way, the fibers will slip as they weave along the balloon cone to the straight section, and accumulate at the root of the balloon cone ( Figure 30 As shown in the figure, only when the braiding density is adjusted to a very small degree (such as 5-20 meshes) can the fibers cross the balloon cone and reach the balloon straight section. After the present invention adds a reinforcement layer, the reinforcement layer helps the fibers to be positioned. The fibers can form interlacing points at the expected position and be fixed at that position to form a uniform braided network ( Figure 31 shown).

[0061] like Figure 28 and Figure 29 As shown, when the diameter of the balloon body 1 of the present invention is 8 mm, compared with a common balloon, the bursting pressure of the medical balloon of the present invention is significantly higher than that of the common balloon, and the compliance is significantly lower than that of the common balloon.

[0062] like Figure 34 and Figure 35 The medical balloon of the present invention was used to conduct filling experiments in animal experiments, angiography was performed during the filling process, and the animal heart was dissected after the experiment was completed. The experimental results showed that the tissue structure of the contact area between the animal heart and the balloon was not damaged.

[0063] Example 5 The balloon tube is blow-molded in a balloon forming machine (balloon forming mold 7) to form the balloon body 1. The balloon tube can be made of Pebax, PA, PET, or a blend of these materials. Evenly distributed raised glue dots are formed on the balloon cone 2 through an array of glue injection. The glue dots can be made of a TPU resin solution, polyacrylate glue, polyurethane glue, or silicone glue. During the interweaving process, the braided fibers climb along the glue dots, forming a uniform mesh structure on the balloon surface. The braided balloon is then bonded using a TPU resin solution, polyacrylate glue, polyurethane glue, epoxy glue, or other adhesives to secure the fibers to the balloon surface.

[0064] Example 6 The balloon tube is blow-molded in a balloon forming machine (balloon forming mold) to form the balloon body 1. The inner surface of the balloon forming mold, corresponding to the balloon cone, has a frosted texture, and the middle section of the mold features a concave, narrow neck. The balloon tube can be made of Pebax, PA, PET, or a blend of these materials. A reinforcement layer 4 is evenly applied to the balloon body 1 by spraying. This layer can be made of a TPU resin solution, polyacrylate glue, polyurethane glue, silicone glue, or a combination of these. Depending on the material of the reinforcement layer 4, it can be cured naturally at room temperature or by UV light. After the reinforcement layer 4 is applied, it is braided. The fiber strands can be made of polyphenylene phthalate, aromatic polyester, polyethylene, or nickel-titanium alloy. The fibers are interwoven to form a uniform woven fiber layer on the balloon surface. The braided fibers converge at the narrow neck, creating a constraint, and the deformation at the neck is limited to 1%-2%.

[0065] Example 7 The balloon tube is blow-molded in a balloon forming machine (balloon forming mold 7) to form the balloon body 1. The balloon tube can be made of materials such as Pebax, PA, PET, or a blend of these. A reinforcement layer 4 is evenly applied to the balloon body 1 by spraying. The reinforcement layer 4 can be made of a TPU resin solution, polyacrylate glue, polyurethane glue, silicone glue, or a combination of resin solutions and glues. Depending on the material of the reinforcement layer 4, it can be cured naturally at room temperature or by UV light. After the reinforcement layer 4 is applied, the fibers are braided. The fibers can be made of polyphenylene phthalate, aromatic polyester, polyethylene, or nickel-titanium alloy. The fibers are interwoven to form a woven fiber layer 5 of a specific density on the balloon surface. The density can range from 40 to 90 mesh. The drug coating is applied within the mesh formed by the woven fiber layer 5. The woven fiber layer 5 forms a grid on the balloon surface, dividing the balloon into multiple zones. Some zones can be shielded using tooling. Based on specific therapeutic needs, the drug is sprayed and distributed within specific grid zones for targeted drug delivery. The drug may be paclitaxel, rapamycin, everolimus, α-reductase inhibitor or any combination of the above drugs.

[0066] Example 8 The medical balloon includes a balloon body 1, a reinforcement layer 4 is provided on the outside of the balloon body 1, and a woven fiber layer 5 is wrapped on the outside of the reinforcement layer 4. The weaving density of the woven fiber layer 5 can be between 40-90 meshes, and the weaving angle can be between 100-160°. The weaving method can be a combination of axial fibers and radial fibers, or it can be formed by interweaving only radial fibers. The axial fibers can be 8 strands, 12 strands, 24 strands, 36 strands, etc., and the radial fibers can be 36 strands, 72 strands, 96 strands, etc. The axial fibers and radial fibers can be combined with different numbers of strands to form different degrees of coverage on the balloon body 1. The larger the coverage area, the higher the pressure resistance of the balloon and the lower the compliance; the smaller the coverage area, the better the flexibility of the balloon.

[0067] With the reinforcement layer 4 as a foundation, the braided fibers maintain a consistent weave density in the balloon's tapered portion 2 and the straight portion, resulting in a highly consistent overall balloon structure and uniform anisotropy. Furthermore, the combination of axial and radial fibers provides restraint in both the axial and radial directions. This ensures consistent pressure across different parts of the balloon during inflation, preventing stress concentration.

[0068] Example 9 like Figure 22 As shown, the braided fibers can be round, flat, or shaped, with cross-sections of circular, oval, triangular, or square shapes. Compared to round fibers, flat or shaped fibers have a larger contact area with the balloon and reinforcement layer 4, resulting in a greater interfacial interaction. Furthermore, the braided fibers can be a braided tape composed of multiple strands of fiber. The tape can be composed of round, flat, or shaped fibers, and has a larger contact area than a fiber tape.

[0069] Conventional fiber strands are mostly round filaments with smooth surfaces, making them difficult to adhere to the balloon surface. Fibers with specialized structures, such as ciliated fibers, can be wrapped with a reinforcing layer to increase the contact area, fostering stronger intermolecular interactions and increasing the number of reactive sites, enabling the fibers to be positioned on the balloon surface. Ciliated fibers can be formed through methods such as plasma treatment, sandblasting, sand milling, electrospinning, and chemical vapor deposition.

[0070] Example 10 A medical balloon catheter consists of a medical balloon, the distal end of which is connected to a tip made of materials such as Pebax, PA, and TPU. The proximal end of the balloon is connected to an outer tube made of materials such as Pebax, PA, PI, and PP. The proximal end of the outer tube is connected to the catheter hub. The tip used in this case is made of Pebax3533, which is relatively soft and less likely to damage the vessel wall and tissue. In animal experiments, this balloon catheter successfully navigated tortuous vessels to reach the treatment site. Postoperative dissection revealed that the vessel wall retained its smooth surface and was intact.

[0071] Example 11 like Figure 23 As shown, uneven glue application or the generation of tiny bubbles during glue application can cause pits 15 to form on the balloon and fiber surfaces (pits 15 appear after the bubbles disappear). By selecting a glue with a different viscosity, such as a lower viscosity glue, the balloon and fiber surfaces can be more easily coated, thus avoiding pits 15.

[0072] Before the treatment, the surface tension of the balloon and fiber is high, and the glue is not easy to spread evenly on the surface. Instead, it tends to condense together, resulting in an uneven surface and the formation of pits 15 ( Figure 24 By activating the balloon and fiber, the surface tension of the material surface can be reduced, the surface wettability of the material can be improved, and the glue can be spread more evenly on the balloon and fiber surface, thus avoiding glue aggregation and thus avoiding the formation of pits ( Figure 25 shown).

[0073] The glue is applied to the balloon surface by spraying through the nozzle 16. The degree of glue atomization can be changed by adjusting the air pressure or the nozzle aperture size of the nozzle 16 (such as a small aperture nozzle). The higher the atomization degree, the smaller and more uniform the glue atomized particles 17 formed, and the more evenly distributed on the balloon surface ( Figure 26 If the glue atomization degree is low, the glue atomization particles 17 formed are uneven, which will cause the glue layer on the balloon surface to be uneven ( Figure 27 shown).

[0074] The medical balloon provided by the present invention has the following advantages: 1) The woven fiber layer on the balloon surface is evenly distributed, with higher pressure resistance The woven fiber layer is evenly distributed across the balloon surface, making the pressure distribution inside the balloon more uniform, thereby improving the balloon's pressure resistance. When dilating stenotic lesions, the balloon is less likely to be punctured by calcified lesions.

[0075] 2) Improved balloon weavability Through the design of the rough surface structure, reinforcement layer and fixed layer, the woven fibers can form stable interweaving points in the area where the diameter of the balloon cone changes greatly, avoiding the phenomenon of woven fiber slippage when the angle of the balloon cone is too large, thereby avoiding peeling between the woven fiber layer and the balloon to form a sandwich, avoiding the deterioration of the balloon's pressure resistance, and preventing water from entering the woven fiber layer.

[0076] 3) Balloon has better cornering performance The design of a roughened surface structure, a reinforcement layer, and a fixed layer creates a uniform woven fiber layer while maintaining a small taper length and a large angle. This maintains the balloon's pressure resistance while allowing for greater design flexibility in the balloon's taper dimensions. The reduced taper length, and consequently, the overall balloon length, facilitates passage through tortuous vessels and further improves its cornering performance, preventing damage to the vessel wall caused by excessive balloon length during cornering.

[0077] 4) Smaller outer diameter, softer balloon, and better permeability Improved braidability expands the range of fiber sizes available for braiding. A combination of smaller diameter fibers can be used for balloon braiding, reducing overall balloon wall thickness and outer diameter, increasing balloon flexibility and further enhancing the balloon's cornering performance.

[0078] 5) More accurate balloon size The uniform distribution of the braided fiber layer across the balloon surface constrains the balloon's dimensions, resulting in a more precise diameter and length after inflation. This reduces tissue tearing caused by overexpansion and avoids vascular or tissue complications. Conventional bare balloons are prone to variations in diameter and length after inflation, resulting in relatively high compliance. The braided fiber layer of the present invention completely covers the balloon surface, providing a strong constraint in both the axial and radial directions, reducing compliance and enabling more precise dimensional control.

[0079] 6) Prevent slipping during treatment The woven fiber layer on the surface of the balloon can increase the friction of the balloon surface. During the actual treatment process, it can better fix the balloon to the area to be treated, prevent the balloon from sliding during the operation, and avoid damage to surrounding tissues due to the sliding of the balloon.

[0080] 7) One-piece molding For special-shaped balloons, the braided fibers can be applied to different areas of the balloon and formed into one piece, which reduces the complex process of distribution processing and increases production efficiency.

[0081] 8) Neck restraint The braided fibers constrain the narrow neck of the balloon, precisely controlling the size of the narrow neck so that the balloon can be accurately positioned.

[0082] 9) Targeted drug delivery In the grid formed by weaving on the surface of the balloon, drugs can be loaded into different areas according to actual treatment needs, providing more precise and effective targeted treatment.

[0083] The present invention has a reinforcing layer between the balloon body and the woven fiber layer, which can help position the woven fibers so that the woven fibers can form a more uniform mesh structure on the balloon surface during the weaving process. A fixing layer is provided outside the woven fiber layer, which can fix the fibers on the balloon surface, provide restraint for the balloon, thereby improving the pressure resistance of the balloon and reducing the compliance of the balloon. The reinforcing layer provides a transition base for the fixation between the balloon body and the fibers, so that the woven fiber layer can be more firmly fixed on the balloon body, preventing the woven fiber layer as a whole from slipping on the balloon surface. In addition, by adding a protrusion or frosted structure to the surface of the balloon cone, or directly molding the balloon in a balloon mold with a groove or frosted structure, a balloon body with a rough surface structure on the cone is obtained, which can also provide a positioning function for the woven fibers, thereby ensuring the uniformity of the woven mesh structure.

[0084] On the basis of stable weaving, there is a great deal of room for combination adjustment of the material and wire diameter of radial fibers or axial fibers. By selecting appropriate materials and wire diameters, the balloon wall thickness can be reduced while ensuring the performance of the balloon, making the balloon softer and facilitating the retraction and retraction of the balloon.

[0085] The present invention can achieve stable weaving, and even if the taper of the balloon cone is large, a uniform mesh weaving structure can be formed. The length of the balloon cone can be reduced, thereby avoiding unnecessary damage to surrounding tissues.

[0086] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A medical balloon, characterized in that: The invention comprises a balloon body, wherein the balloon body has a balloon cone portion, a reinforcement layer is provided on the outside of the balloon cone portion, and the reinforcement layer is wrapped with a woven fiber layer; the diameter of the balloon body is greater than or equal to 8 mm, the cone angle α of the balloon cone portion is greater than or equal to 30°, and the average thickness of the reinforcement layer ranges from 0.002 to 0.015 mm.

2. The medical balloon according to claim 1, characterized in that: The reinforcing layer is a flexible resin coating, the braided fiber layer is wrapped with a fixing layer, and the fixing layer is a flexible resin coating.

3. The medical balloon according to claim 1, characterized in that: The reinforcing layer has polar groups and a surface that is sticky and rough.

4. The medical balloon according to claim 1, characterized in that: The surface of the balloon cone has a rough surface structure, and the rough surface structure includes a frosted surface structure or a convex surface structure.

5. The medical balloon according to claim 1, characterized in that: A drug coating is provided in the mesh formed by the woven fiber layer.

6. The medical balloon according to claim 1, characterized in that: The braided fiber layer forms a radial limiting structure at the narrow neck of the balloon body, the reinforcement layer is provided on the balloon cone surface on both sides of the narrow neck of the balloon body, and the braided fiber layer is wrapped outside the reinforcement layer, and the braided fiber layer is wrapped outside the braided fiber layer.

7. A method for preparing the medical balloon according to claim 4, characterized in that: The following steps are involved: A rough surface structure is formed on the surface of the balloon cone by grinding or sandblasting, and then a flexible resin is coated on the balloon cone to form the reinforcement layer, and then the braided fiber layer is braided outside the reinforcement layer.

8. A method for preparing the medical balloon according to claim 4, characterized in that: The following steps are involved: Grooves or frosted structures are formed on the cavity wall corresponding to the balloon forming mold and the balloon cone, and the balloon material tube is blow-molded in the balloon forming mold to obtain the balloon body. A rough surface structure is formed on the surface of the balloon cone, and then a flexible resin is coated on the balloon cone to form the reinforcement layer, and then the woven fiber layer is woven outside the reinforcement layer.

9. A method for preparing the medical balloon according to claim 4, characterized in that: The following steps are involved: A dotted structure is injection molded on the surface of the balloon cone of the balloon material tube, and then blow molded to obtain the balloon body. A rough surface structure is formed on the surface of the balloon cone. A flexible resin is then coated on the balloon cone to form the reinforcement layer, and then the braided fiber layer is woven outside the reinforcement layer.

10. A balloon catheter, characterized in that: The medical balloon comprises the medical balloon according to any one of claims 1 to 6.

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