Non-latex leak-proof disposable sterile urinary catheter

Abstract

This invention discloses a latex-free, leak-proof, disposable sterile urinary catheter, relating to the field of urinary catheter technology. It includes a catheter tip, a catheter balloon, and a mid-section catheter. The invention utilizes a hemispherical conical tip with a double-layer hydrophilic coating, combined with a flexible tube body and a spiral skeleton. This allows for smooth insertion, conforming to the curvature of the urethra, reducing mucosal damage and discomfort throughout the entire treatment cycle. Multiple sets of side holes in a funnel shape, a micron-sized filter, a spiral flow channel, and multiple layers of hydrophobic and negatively charged coating work synergistically to effectively prevent clogging, inhibit scale and stone formation, and extend the service life. A connected fluid support channel forms hydraulic support, which, together with the spiral skeleton, prevents the tube from flattening or collapsing, ensuring smooth drainage. A silver ion capsule combined with a hydrophobic coating constructs a dual antibacterial system, inhibiting biofilm growth, reducing the risk of urinary tract infections, and improving patient comfort and catheter lifespan.

Description

Technical Field

[0001] This invention relates to the field of urinary catheter technology, and more specifically, to a latex-free, leak-proof, disposable sterile urinary catheter. Background Technology

[0002] In numerous medical scenarios, including clinical urology, postoperative care, intensive care, and routine treatment of elderly patients, urinary catheters serve as fundamental medical consumables for urine drainage, bladder decompression, and urinary tract care. Their applications are widespread, making them an indispensable type of sterile interventional device in the daily clinical practice of medical institutions. With the continuous improvement of modern medical service systems, the demand for home care, rehabilitation care, and care for long-term bedridden patients continues to rise. The frequency and scale of clinical use of disposable urinary catheters are also steadily increasing. Simultaneously, the public is increasingly concerned about the safety, comfort, and compatibility of medical consumables during use. In response to more detailed and stringent practical requirements, most urinary catheters widely used in traditional clinical practice are made primarily of natural latex. While this material possesses a certain degree of flexibility and shaping ability, meeting the basic needs of urinary catheterization, natural latex contains various specific protein allergens. During medical procedures, indwelling use, and prolonged human contact, it can easily trigger varying degrees of skin and mucous membrane allergic reactions. This can cause discomfort such as redness, swelling, itching, and stinging at the urethral opening, and significantly increase the probability of urinary system-related complications, greatly affecting the patient's physical and mental comfort and recovery process during treatment.

[0003] Nowadays, the medical industry is paying more and more attention to the user experience and stability of interventional sterile devices. Most of the general-purpose disposable sterile urinary catheters on the market are relatively simple in terms of overall structural sealing design and have not been optimized for specific clinical indwelling use scenarios. They can only achieve basic urine drainage functions. In addition, the current clinical diagnosis and treatment advocates the use of lightweight, low-irritation and high-safety consumables. New disposable sterile urinary catheters have become a practical medical device product that urgently needs to be developed and launched in the process of upgrading clinical medical consumables.

[0004] In practical use, existing technologies often suffer from problems. Traditional catheters, with their sharp conical or right-angled edges, are prone to damaging the urethral mucosa and causing mechanical damage to the urethral sphincter and prostate during insertion, leading to severe pain and bleeding in patients. Furthermore, the lack of effective lubrication on the outer wall of traditional catheters results in a high coefficient of friction, significant insertion resistance, and an inability to conform to the natural curvature of the urethra. This can cause rigid compression and traction on the urethral wall, resulting in a strong foreign body sensation during long-term indwelling and potentially leading to chronic urethral inflammation and mucosal edema. Therefore, it is necessary to provide a latex-free, leak-proof, disposable sterile catheter to address these technical issues. Summary of the Invention

[0005] The purpose of this invention is to provide a latex-free, leak-proof, disposable sterile urinary catheter to solve the above-mentioned problems.

[0006] To achieve the above objectives, an embodiment of the present invention provides the following technical solution: A latex-free, leak-proof, disposable sterile urinary catheter includes a catheter head, which comprises an ultra-soft tube located in the middle. One end of the ultra-soft tube is connected to a tapered tip. Multiple side holes are evenly distributed on the outer surface of the ultra-soft tube. A micron-sized filter is fixedly connected to the inner cavity of each side hole. A hydrophilic coating is fixedly connected to the outer surface of the ultra-soft tube at the front end, and a superhydrophobic coating is fixedly connected to the inner wall of the inner cavity at the front end. The catheter balloon comprises a rigid tube located in the middle, and an elastic balloon is fixedly connected to the outer surface of the rigid tube. The inner wall of the catheterization balloon is fixedly connected with a mid-section superhydrophobic coating. The inner cavity of the rigid tube is uniformly provided with multiple fluid support channels. The mid-section catheter includes a mid-section ultra-soft tube located in the middle. The inner cavity of the mid-section ultra-soft tube is uniformly provided with multiple fluid support channels. The inner cavity of the mid-section ultra-soft tube is fixedly connected with a helical skeleton. The inner cavity of the mid-section ultra-soft tube is divided into helical grooves by the helical skeleton. The inner wall of the helical groove is fixedly connected with a negatively charged nano-coating. An external connector is installed at one end of the mid-section ultra-soft tube.

[0007] As a further improvement of the present invention, the end of the tapered tip away from the ultra-soft pipe is semi-circular, and the side hole is funnel-shaped with a smaller inner diameter and a larger outer diameter.

[0008] As a further improvement of the present invention, a porous superhydrophobic coating is fixedly connected to the side wall of the inner cavity of the side hole, and the porous superhydrophobic coating is integrally formed with the front end inner superhydrophobic coating.

[0009] As a further improvement of the present invention, the number of fluid support channels one and fluid support channels two are the same, and the fluid support channels one and fluid support channels two are connected in series.

[0010] As a further improvement of the present invention, the elastic bladder is a teardrop-shaped elastic sleeve, and the end of the fluid support channel one that is away from the fluid support channel two is connected to the elastic bladder.

[0011] As a further improvement of the present invention, the outer surface of the mid-section ultra-soft pipe is wrapped with a mid-section outer hydrophilic coating, and the outer surface of the spiral skeleton is wrapped with a skeleton superhydrophobic coating.

[0012] As a further improvement of the present invention, a plurality of silver ion capsules are uniformly and fixedly connected to the inner wall of the spiral groove, and the silver ion capsules are embedded and fixed in the inner cavity of the negatively charged nano-coating.

[0013] As a further improvement of the present invention, the external connector includes a urine drainage connector that communicates with the ultra-soft pipe. The urine drainage connector, the rigid pipe, and the middle section of the ultra-soft pipe form a complete circular communicating pipe with the same axis.

[0014] As a further improvement of the present invention, an outer sleeve is fixedly connected to the outer surface of the middle section of the ultra-soft pipe, and the outer sleeve is an annular sleeve.

[0015] As a further improvement of the present invention, the end of the fluid support channel two away from the fluid support channel one is connected to the external connector, and the outer surface of the external connector sleeve is connected to a water injection connector.

[0016] Compared with the prior art, the advantages of this invention are: (1) This solution uses a bullet-shaped, hemispherical cone tip design for the catheter tip, combined with a synergistic lubrication mechanism where the hydrophilic coating at the front and the hydrophilic coating in the middle form a dense and smooth hydration layer upon contact with water. This eliminates the damage to the urethral mucosa caused by the sharp tip of traditional catheters, transforming the mechanical stimulation during insertion into smooth sliding through surface contact. This significantly reduces the coefficient of friction, allowing the catheter to pass painlessly through physiologically narrow areas such as the urethral sphincter and prostate. At the same time, the high flexibility of the ultra-soft tubing and the spiral skeleton embedded in the lumen do not increase the external surface area. The structure of the catheter allows it to bend smoothly with the natural curvature of the urethra, avoiding the rigid pressure and traction damage to the urethral wall caused by rigid catheters. The segmented hardness gradient design further ensures functional zones: a soft tip to prevent damage, a rigid balloon segment to prevent collapse, and an ultra-soft rear segment for secure fixation. This allows the catheter to be fixed to the inner thigh to form a natural hanging arc during long-term indwelling, minimizing the patient's foreign body sensation and chronic urethral irritation. This reduces catheter-related urethral damage, pain, and patient discomfort, achieving comfort and safety throughout the entire cycle from insertion to indwelling.

[0017] (2) The side holes in this design adopt a funnel-shaped configuration with a smaller inner hole and a larger outer hole, combined with a multi-directional distribution array. The Venturi effect is used to accelerate urine aspiration and ensure that there is always an opening aligned with the urine flow field regardless of the orientation of the catheter. This solves the problem of drainage interruption caused by bladder wall adhesion in traditional single-hole catheters. At the same time, the micron filter selectively intercepts blood clots and tissue debris, preventing large particles from entering the main channel and causing deep blockage. It also retains the redundancy of the pores to ensure that blood clots do not completely block the channel. The spiral flow channel design with spiral grooves induces urine to rotate. The eddy current, with its centrifugal and shear forces generated by the secondary flow effect, washes away the attached material from the tube wall. Combined with the electrostatic repulsion of calcium and magnesium ions by the negatively charged nano-coating, it inhibits the nucleation and growth of stone crystals such as magnesium ammonium phosphate from the source. Furthermore, the entire lumen is protected by a superhydrophobic protective system consisting of an inner superhydrophobic coating, a porous superhydrophobic coating, and a skeleton superhydrophobic coating. This makes the urine flow in a bead-like manner, making it difficult to wet the tube wall. This eliminates the basis for crystal and biofilm adhesion, significantly extending the effective service life of the catheter and reducing unplanned replacements due to blockage and crusting.

[0018] (2) This scheme uses an internal hydraulic support system formed by connecting fluid support channel one and fluid support channel two. After the catheter is inserted into the body, liquid is injected to expand and anchor the elastic capsule. At the same time, the liquid fills the support channels inside the rigid and ultra-soft tubes. The incompressibility of the liquid provides immediate rigid support for the catheter. At this time, the elastic deformation of the spiral skeleton and the internal hydraulic pressure work together. Even if the catheter is squeezed and bent, it can recover its original shape by hydraulic rebound and skeleton elasticity after the pressure is released, ensuring that the lumen is continuously open and the drainage is uninterrupted. This solves the structural defects of traditional soft urinary catheters that are easy to break and collapse. At the same time, the silver ion capsule slowly releases silver ions or chlorhexidine antibacterial agent during the flow of urine, kills the bacteria flowing through and destroys their cell walls, and blocks the path of bacteria to form biofilm on the tube wall and retrograde infection of the bladder. Through the dual protection system of chemical killing of antibacterial agents and physical inhibition of hydrophobic surfaces, the incidence of catheter-related urinary tract infections is reduced and the generation of odor is reduced. This provides reliable anti-breakage support and anti-infection protection for long-term indwelling patients. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a side view of the overall structure of the present invention; Figure 3 This is a schematic diagram of the internal structure of the present invention in half section; Figure 4 This is a schematic diagram of the cross-sectional structure of the catheter tip of the present invention; Figure 5 This is a partial structural diagram of the present invention; Figure 6 This is a schematic diagram of the cross-sectional structure of the catheterization balloon of the present invention; Figure 7 This is a schematic diagram of the cross-sectional structure of the mid-section of the ureter according to the present invention; Figure 8 This is a schematic diagram of the cross-sectional structure of the external connector of the present invention.

[0020] Explanation of the labels in the diagram: 1. Catheter tip; 101. Ultra-soft tubing; 102. Conical tip; 103. Side hole; 104. Micron filter; 105. Porous superhydrophobic coating; 106. External hydrophilic coating at the tip; 107. Internal superhydrophobic coating at the tip; 2. Catheter balloon; 201. Rigid tubing; 202. Elastic balloon; 203. Internal superhydrophobic coating in the middle section; 204. Fluid support channel one; 3. Middle section catheter; 301. Mid-section ultra-soft tubing; 302. Fluid support channel two; 303. External hydrophilic coating in the middle section; 304. Spiral skeleton; 305. Superhydrophobic coating on the skeleton; 306. Spiral groove; 307. Negatively charged nano-coating; 308. Silver ion capsule; 4. External connector; 401. Urine drainage connector; 402. External sleeve; 403. Injection connector. Detailed Implementation

[0021] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0022] Example 1: Please see Figure 1 - Figure 4 A latex-free, leak-proof, disposable sterile urinary catheter includes a catheter head 1, which includes an ultra-soft tube 101 located in the middle. One end of the ultra-soft tube 101 is connected to a tapered tip 102. Multiple side holes 103 are uniformly opened on the outer surface of the ultra-soft tube 101. A micron filter 104 is fixedly connected to the inner cavity of the side holes 103. A front-end hydrophilic coating 106 is fixedly connected to the outer surface of the ultra-soft tube 101, and a front-end superhydrophobic coating 107 is fixedly connected to the inner wall of the ultra-soft tube 101.

[0023] Specifically, the tapered tip 102 is semi-circular at the end away from the ultra-soft pipe 101, and the side hole 103 is trumpet-shaped with a smaller inner diameter and a larger outer diameter. A porous superhydrophobic coating 105 is fixedly connected to the inner wall of the side hole 103, and the porous superhydrophobic coating 105 is integrally formed with the front end inner superhydrophobic coating 107.

[0024] The ultra-soft tubing 101 is the main load-bearing structure of the catheter head 1, adopting a hollow cylindrical tube configuration. Its inner lumen forms the main channel for urine drainage. The ultra-soft tubing 101 is made of medical-grade silicone material, which has excellent biocompatibility, contains no latex, and can effectively avoid latex allergic reactions. The ultra-soft tubing 101 provides a structural mounting base for the conical tip 102, side holes 103, and micron filter 104. Its inner lumen forms the initial channel for urine to flow from the bladder to the mid-section of the catheter 3. The conical tip 102 is connected to one end of the ultra-soft tubing 101, forming an overall shape. The slender, bullet-shaped tip gradually transitions into a hemispherical shape as it moves away from the ultra-soft tubing 101. The entire outer contour has no sharp edges or right-angle turns. The slender, tapered portion gradually expands the urethral cavity, allowing the urethral mucosa to gradually adapt to the catheter's entry. Furthermore, the hemispherical tip eliminates the point contact stress concentration that can occur with traditional tapered tips, distributing the insertion force evenly over a larger contact area. This avoids cutting and scratching the mucosa when passing through physiologically narrow urethral areas. The tapered tip 102 and the ultra-soft tubing 101 are integrally molded from the same medical-grade silicone material, ensuring seamless contact between the tip and the main tubing. The components are seamless, avoiding stress concentration and potential fracture risks at material interfaces. Multiple side holes 103 are formed on the outer surface of the ultra-soft conduit 101, evenly distributed along its circumference and axial direction. Each side hole 103 has a funnel-shaped configuration, with a smaller diameter at the inner end and a larger diameter at the outer end. This shape creates a gradually narrowing flow channel for urine, which, according to Bernoulli's principle, gradually increases in velocity while decreasing in pressure, facilitating smooth urine flow and reducing tissue debris accumulation. The retention at the orifice allows the remaining side holes 103 to continue functioning normally even when some of them are attached to the bladder wall or greater omentum, thus preventing drainage interruption caused by blockage of a single side hole. The micron filter 104 is made using precision weaving or laser perforation technology and is made of medical-grade polyethersulfone or nylon material. It has excellent chemical stability and biocompatibility, is resistant to hydrolysis and oxidation, and will not degrade after long-term use in the urine environment. For patients with hematuria, the micron filter 104 ensures that blood clots do not completely block the channel and also prevents larger tissue debris from entering the deep lumen and accumulating, causing blockage.

[0025] The front end has an external hydrophilic coating 106 that is fixedly attached to the entire outer surface of the ultra-soft tube 101 and the conical tip 102. This coating is nanoscale thick and is firmly attached to the surface of the silicone substrate by chemical grafting or physical adsorption. The coating material is polyvinylpyrrolidone or polyethylene oxide hydrophilic polymer, which has high hydrophilicity. When it comes into contact with water, it can quickly absorb water and form a smooth hydration layer on the surface. The presence of the hydration layer reduces the mechanical damage of the catheter to the urethral mucosa and reduces the incidence of mucosal edema and inflammatory response. The front end has an internal superhydrophobic coating 107 that is fixedly attached to the inner wall of the ultra-soft tube 101. This coating is nanoscale thick.

[0026] The porous superhydrophobic coating 105 and the front-end inner superhydrophobic coating 107 serve as functional coatings for the inner wall of the ultra-soft pipe 101. The superhydrophobic surface causes urine to flow in a bead-like manner, reducing the contact area and contact time between urine and the pipe wall, thereby reducing the probability of calcium and magnesium ions in the urine adhering to and crystallizing on the pipe wall. The porous superhydrophobic coating 105 and the front-end inner superhydrophobic coating 107 form a micro-nano composite rough structure on the inner surface of silica gel through gelation or chemical vapor deposition, and are further modified with low surface energy materials to achieve the superhydrophobic standard. A fluorosilane-modified silica nanoparticle composite system is often used for support. Fluorosilane provides low surface energy properties, while silica nanoparticles construct the micro-nano rough structure. The two work synergistically to achieve the superhydrophobic effect. This coating system has good chemical stability and biocompatibility and does not degrade in the urine environment.

[0027] Example 2: Please see Figure 1 - Figure 7 A latex-free, leak-proof, disposable sterile urinary catheter includes a urinary catheter balloon 2. The urinary catheter balloon 2 includes a rigid tube 201 located in the middle. An elastic bladder 202 is fixedly connected to the outer surface of the rigid tube 201. A superhydrophobic coating 203 is fixedly connected to the inner wall of the urinary catheter balloon 2 in the middle section. Multiple fluid support channels 204 are uniformly opened in the inner cavity of the rigid tube 201.

[0028] Specifically, the number of fluid support channels 1 204 and fluid support channels 2 302 are the same, and fluid support channels 1 204 and fluid support channels 2 302 are connected. The elastic bladder 202 is a teardrop-shaped elastic sleeve, and the end of fluid support channel 1 204 away from fluid support channel 2 302 is connected to the elastic bladder 202.

[0029] The rigid tube 201 is the main load-bearing structure of the catheter balloon 2. It adopts a hollow cylindrical tube configuration. Compared with the ultra-soft tube 101 of the catheter head 1, the rigid tube 201 has a thicker wall and higher material hardness to provide sufficient radial support. The inner lumen of the rigid tube 201 is connected to the inner lumen of the ultra-soft tube 101 of the catheter head 1 and the inner lumen of the mid-section ultra-soft tube 301 of the mid-section catheter 3, forming a complete urine drainage channel. The rigid tube 201 is made of medical-grade silicone composite material, in which a rigid support material is embedded. The rigid support material is medical-grade polyurethane or polyethylene, which is embedded in the silicone matrix in a fibrous or mesh form to form a composite material structure. Its hardness is higher than that of the soft silicone of the catheter head 1, which can keep the lumen open when the balloon is inflated and prevent the tube wall from collapsing. The elastic balloon 202 is fixedly connected to the outer surface of the rigid tube 201 and is teardrop-shaped. The elastic balloon 202 features a teardrop-shaped design, resulting in an asymmetrical shape with one end larger and the other smaller when inflated. The larger end faces the bottom of the bladder, and the smaller end faces the bladder neck. When not inflated, the elastic balloon 202 fits snugly against the outer surface of the rigid tube 201. Its overall outer diameter is similar to other parts of the catheter, which does not affect insertion. The teardrop shape increases the contact area with the bladder wall, making the balloon more closely conform to the anatomical shape of the bladder and reducing the feeling of a foreign body. The larger contact area disperses the local pressure of the balloon on the bladder wall, reducing the risk of compressive damage and ischemic necrosis of the bladder mucosa. The reduced gaps prevent bypass leakage and improve the sealing performance of the indwelling catheter. The elastic balloon 202 is made of highly elastic medical-grade silicone or latex substitute material, which has excellent elastic recovery properties and will not suffer fatigue damage during repeated filling and aspiration cycles.

[0030] The superhydrophobic coating 203 in the middle section is fixedly connected to the inner wall of the rigid tube 201. It works in conjunction with the superhydrophobic coating 107 at the front end to ensure that the entire inner wall of the catheter has continuous anti-fouling and anti-crystallization protection. Multiple fluid support channels 204 are evenly opened in the wall of the rigid tube 201 and are evenly distributed along the circumference of the rigid tube 201. One end of the fluid support channel 204 is connected to the inner cavity of the elastic bladder 202, and the other end is connected to the fluid support channel 302, forming a complete fluid passage from the external connector 4 to the elastic bladder 202. The even distribution of multiple channels ensures the uniformity of the filling of the elastic bladder 202 and the balance of the supporting force of the rigid tube 201.

[0031] Example 3: Please see Figure 1 - Figure 8A latex-free, leak-proof, disposable sterile urinary catheter includes a mid-section urinary catheter 3, which includes a mid-section ultra-soft tube 301 located in the middle. The inner cavity of the mid-section ultra-soft tube 301 is uniformly provided with multiple fluid support channels 302. A spiral skeleton 304 is fixedly connected to the inner cavity of the mid-section ultra-soft tube 301. The inner cavity of the mid-section ultra-soft tube 301 is divided into spiral grooves 306 by the spiral skeleton 304. A negatively charged nano-coating 307 is fixedly connected to the inner wall of the spiral grooves 306. An external connector 4 is installed at one end of the mid-section ultra-soft tube 301.

[0032] Specifically, the outer surface of the mid-section ultra-soft pipe 301 is wrapped with a mid-section outer hydrophilic coating 303, the outer surface of the spiral skeleton 304 is wrapped with a skeleton superhydrophobic coating 305, and the inner wall of the spiral groove 306 is uniformly and fixedly connected with multiple silver ion capsules 308, which are embedded and fixed in the inner cavity of the negatively charged nano-coating 307.

[0033] The external connector 4 includes a urine drainage connector 401 that is connected to the middle section of the ultra-soft pipe 301. The urine drainage connector 401, the rigid pipe 201 and the middle section of the ultra-soft pipe 301 form a complete circular connecting pipe with the same axis. An external sleeve 402 is fixedly connected to the outer surface of the middle section of the ultra-soft pipe 301. The external sleeve 402 is an annular sleeve. The end of the fluid support channel 2 302 away from the fluid support channel 1 204 is connected to the external connector 4. A water injection connector 403 is connected to the outer surface of the external sleeve 402.

[0034] Among them, the mid-section ultra-soft tube 301 is the main load-bearing structure of the mid-section urinary catheter 3. It adopts a hollow circular tube configuration. The material hardness of the mid-section ultra-soft tube 301 is significantly lower than that of the rigid tube 201. One end of the mid-section ultra-soft tube 301 is connected to the rigid tube 201 of the catheterization balloon 2, and the other end is equipped with an external connector 4. The second fluid support channel 302 is evenly opened in the tube wall of the mid-section ultra-soft tube 301. The number is the same as that of the first fluid support channel 204, and they are connected one-to-one with the first fluid support channel 204. One end of the second fluid support channel 302 is connected to the first fluid support channel 204, and the other end extends to the external connector 4 and is connected to the water injection connector 403 of the external connector 4.

[0035] A mid-section hydrophilic coating 303 is wrapped and fixed to the outer surface of the mid-section ultra-soft conduit 301. The structure, material, and performance parameters of this coating are the same as those of the front-end hydrophilic coating 106. It is a nano-thickness polyvinylpyrrolidone or polyethylene oxide-based hydrophilic polymer coating that forms a smooth hydration layer upon contact with water. A spiral skeleton 304 is fixedly connected to the inner cavity of the mid-section ultra-soft conduit 301. It is a continuous spiral-shaped protruding skeleton structure that extends spirally along the axial direction of the mid-section ultra-soft conduit 301. The spiral skeleton 304 is integrally formed with the inner wall of the mid-section ultra-soft conduit 301 to ensure a firm connection. The spiral skeleton 304 is made of medical-grade silicone composite material with a hardness slightly higher than that of the mid-section ultra-soft conduit 301. It serves as a structural reinforcement element for the inner cavity of the mid-section ultra-soft conduit 301, undertaking both anti-bending and flow-guiding functions. Yes, its helical configuration transforms radial pressure into tangential stress distribution, enabling the helical skeleton 304 to effectively resist deformation and maintain the open state of the lumen when the mid-section ultra-soft tubing 301 is subjected to external pressure or bending force. The protruding structure of the helical skeleton 304 divides the inner lumen of the mid-section ultra-soft tubing 301 into continuous helical grooves 306, providing a special flow channel configuration for urine flow. The superhydrophobic coating 305 of the skeleton works synergistically with the superhydrophobic coating 107 at the front end and the superhydrophobic coating 203 in the mid-section to ensure that the entire inner wall of the catheter, including the surface of the helical skeleton 304, has continuous anti-fouling and anti-crystallization protection, preventing the helical skeleton 304 from becoming an attachment substrate for bacterial biofilm formation, reducing the risk of infection, while maintaining the smoothness of the inner wall of the helical grooves 306 to ensure the efficient performance of the secondary flow effect.

[0036] The spiral groove 306 is formed by the inner wall of the middle section of the ultra-soft pipe 301 and the spiral skeleton 304, creating a continuous spiral groove flow channel that constitutes the main channel for urine drainage. Its spiral configuration ensures that the urine does not flow in a simple laminar flow, but rather generates a rotating vortex, i.e., a secondary flow, under the combined action of centrifugal force and Coriolis force. This rotating scouring force effectively prevents cell debris and crystals from adhering to the pipe wall. The negatively charged nano-coating 307 is fixedly connected to the inner wall of the spiral groove 306. This coating is nanometer-thick and is formed on the surface of the silicone substrate by chemical grafting or layer-by-layer self-assembly. The negatively charged polymer layer, the negatively charged nano-coating 307, is made of polyanionic polymers such as polyacrylic acid or polystyrene sulfonate. Its molecular chains carry a large number of negatively charged carboxyl or sulfonic acid groups, which perform electrostatic repulsion and anti-crystallization functions. Calcium and magnesium ions in urine are positively charged and are repelled by the negatively charged surface under electrostatic action, making it difficult for them to adhere and accumulate on the tube wall. This electrostatic repulsion thermodynamically inhibits the nucleation and growth of stone crystals such as magnesium ammonium phosphate. Silver ion capsules 308 are uniformly fixed to the inner wall of the spiral groove 306, embedded in the inner cavity of the negatively charged nano-coating 307. The silver ion capsules 308 have a micron-sized spherical or ellipsoidal structure, consisting of a biodegradable polymer shell encapsulating a silver ion or silver nanoparticle core. The capsule shell is made of materials such as polylactic acid, glycolic acid copolymer or polycaprolactone, which has controllable degradation characteristics. The degradation rate can be controlled by adjusting the polymer molecular weight and copolymerization ratio. The capsule shell of silver ion capsule 308 degrades slowly in the urine environment, gradually releasing the silver ions or silver nanoparticles inside. The released silver ions are distributed throughout the lumen of the catheter with the flow of urine, killing bacteria in the middle section and preventing bacteria from retrogradely entering the bladder along the inner wall of the catheter. At the same time, the antibacterial effect of silver ions reduces the reproduction of bacteria in urine and reduces odor.

[0037] The urine drainage connector 401 is connected to the outer connector 4 and is a standard medical Luer connector or tapered connector, compatible with commonly used clinical urine bag drainage tubes. The inner cavity of the urine drainage connector 401 is connected to the inner cavities of the middle section of the ultra-soft tube 301, the rigid tube 201, and the ultra-soft tube 101, forming a complete circular connecting tube with the same axis in each section, ensuring smooth urine flow. The outer sleeve 402 is fixedly connected to the outer surface of the middle section of the ultra-soft tube 301. The annular sleeve configuration has an outer diameter 402 that is larger than the outer diameter of the middle ultra-soft tube 301, forming a flange structure. The outer sleeve 402 has an interface that communicates with the fluid support channel 302. This interface is connected to the water injection connector 403, which is a standard medical one-way valve connector configuration. It allows the filling medium to be injected into the fluid support channel 302 from the outside, but prevents the filling medium from flowing out in reverse. The interface size of the water injection connector 403 matches that of a standard syringe, which is convenient for clinical operation.

[0038] Working principle: During the use of the device, the catheter is in an unfilled state before insertion. The elastic capsule 202 is in close contact with the outer surface of the rigid tube 201. There is no filling medium in the fluid support channel 1 204 and the fluid support channel 2 302. The entire catheter is in a soft state. When the medical staff holds the external connector 4 and pushes the catheter into the patient's urethra, the front hydrophilic coating 106 and the middle hydrophilic coating 303 first come into contact with the urethral mucosa and body fluids. The coatings absorb water and swell quickly, forming a dense and smooth hydration layer, which greatly reduces the coefficient of friction. The hemispherical design of the conical tip 102 allows it to glide smoothly over the urethral sphincter and prostate, avoiding sharp angle cutting. The high flexibility of the middle ultra-soft tube 301 allows it to bend with the natural curvature of the urethra. Although the spiral skeleton 304 provides support, it does not increase the insertion resistance, ensuring that the insertion process is painless and without damage.

[0039] Once the catheter tip 1 reaches the bladder neck, the operator injects an appropriate amount of liquid into the fluid support channel 1 204 and the fluid support channel 2 302 through the water injection connector 403. The liquid enters the elastic bladder 202, causing it to expand. Due to the teardrop-shaped design of the elastic bladder 202, it fully conforms to the inner wall of the bladder, ensuring a tight fit between the bladder and bladder tissue, eliminating gaps, and preventing urine leakage. The injected liquid simultaneously fills the support channels inside the rigid tube 201 and the mid-section ultra-soft tube 301. At this time, the spiral skeleton 304 works together with the internal hydraulic pressure to maintain the mid-section catheter 3 in a rigid support state within the body. Even if it is compressed by a bed sheet or squeezed by a limb, it can rely on the internal hydraulic pressure and the elasticity of the skeleton to restore its original shape, preventing the tube from bending and causing drainage interruption.

[0040] Urine in the patient's bladder flows in through side hole 103 and out through mid-section catheter 3. As urine flows through side hole 103, the venturi effect, caused by its funnel-shaped structure (smaller inside, larger outside), accelerates the flow, rapidly drawing in urine. Regardless of how the catheter rotates within the bladder, the multidirectional distribution of side holes ensures that an opening is always aligned with the urine flow field, preventing any single side hole from being adhered to the bladder wall or tissue. If the urine contains blood clots or tissue debris, a micron-sized filter 104 intercepts them at the side hole entrance, preventing large particles from entering the main channel and causing deep blockage, while allowing small amounts of liquid to pass through. After entering the mid-section ultra-soft tubing 301, the urine is guided by the spiral skeleton 304 and flows along... The spiral groove 306 flows, and this spiral flow channel forces the laminar flow to transform into a rotating vortex. The resulting centrifugal force and shear force continuously scour the pipe wall, carrying away any cell debris and micro-precipitates that may be attached, preventing blockage. The urine flowing through the spiral groove 306 comes into contact with the negatively charged nano-coating 307. The negative charge on the coating surface repels positively charged calcium and magnesium ions in the urine, inhibiting the nucleation and growth of stone crystals such as magnesium ammonium phosphate. The superhydrophobic coating 107 at the front end, the porous superhydrophobic coating 105, and the skeletal superhydrophobic coating 305 make the pipe wall superhydrophobic, making it difficult for urine to wet the pipe wall, further reducing the basis for crystal and biofilm adhesion.

[0041] During the drainage process, as urine flows through the spiral groove 306, the silver ion capsule 308 slowly releases silver ions or chlorhexidine. These antibacterial agents continuously kill the flowing bacteria, destroy the bacterial cell walls, prevent bacteria from forming a biofilm on the tube wall, and block the retrograde infection path of bacteria. Because the hydrophobic environment formed by the superhydrophobic coating 203 in the middle section, the superhydrophobic coating 107 in the front end, the pore superhydrophobic coating 105, and the skeleton superhydrophobic coating 305 is not conducive to the moist conditions required for bacterial reproduction, dual protection can be achieved in conjunction with antibacterial agents.

[0042] For patients with long-term indwelling catheters, the soft material of the mid-section ultra-soft catheter 301, combined with the outer sleeve 402, can fix the catheter to the inner thigh, forming a natural hanging arc, avoiding direct force pulling on the catheter, reducing patient discomfort and the risk of urethral injury. If the catheter is accidentally bent outside the body, the elastic deformation of the spiral skeleton 304, combined with the hydraulic pressure in the internal fluid support channel, can quickly help the catheter return to a straight state after the pressure is released, ensuring continuous drainage. When the drainage operation is completed and the catheter needs to be removed, the fluid inside the fluid support channel 1 204, fluid support channel 2 302 and elastic capsule 202 is drawn out through the water injection connector 403. The elastic capsule 202 contracts and resets, releasing the restriction on the catheter, and then the entire catheter can be smoothly removed from the body.

[0043] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and not restrictive.

[0044] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A latex-free, leak-proof, disposable sterile urinary catheter, characterized in that: include: A urinary catheter head (1) includes an ultra-soft tube (101) located in the middle. One end of the ultra-soft tube (101) is connected to a tapered tip (102). Multiple side holes (103) are uniformly opened on the outer surface of the ultra-soft tube (101). A micron filter (104) is fixedly connected to the inner cavity of the side hole (103). A front-end hydrophilic coating (106) is wrapped and fixedly connected to the outer surface of the ultra-soft tube (101). A front-end superhydrophobic coating (107) is fixedly connected to the inner wall of the ultra-soft tube (101). The catheterization balloon (2) includes a rigid tube (201) located in the middle, an elastic bladder (202) is fixedly connected to the outer surface of the rigid tube (201), a superhydrophobic coating (203) is fixedly connected to the inner wall of the catheterization balloon (2), and multiple fluid support channels (204) are uniformly opened in the inner cavity of the rigid tube (201). The mid-section urinary catheter (3) includes a mid-section ultra-soft tube (301) located in the middle. The mid-section ultra-soft tube (301) has multiple fluid support channels (302) evenly distributed in its inner cavity. The mid-section ultra-soft tube (301) is fixedly connected to a spiral skeleton (304). The mid-section ultra-soft tube (301) is separated into spiral grooves (306) by the spiral skeleton (304). The inner wall of the spiral grooves (306) is fixedly connected to a negatively charged nano-coating (307). An external connector (4) is installed at one end of the mid-section ultra-soft tube (301).

2. The latex-free, leak-proof, disposable sterile urinary catheter according to claim 1, characterized in that: The conical tip (102) is semi-circular at the end away from the ultra-soft pipe (101), and the side hole (103) is trumpet-shaped with a smaller inner diameter and a larger outer diameter.

3. The latex-free, leak-proof, disposable sterile urinary catheter according to claim 1, characterized in that: The inner wall of the side hole (103) is fixedly connected with a porous superhydrophobic coating (105), and the porous superhydrophobic coating (105) is integrally formed with the front inner superhydrophobic coating (107).

4. The latex-free, leak-proof, disposable sterile urinary catheter according to claim 1, characterized in that: The number of fluid support channels one (204) and fluid support channels two (302) are the same, and fluid support channels one (204) and fluid support channels two (302) are connected.

5. The latex-free, leak-proof, disposable sterile urinary catheter according to claim 1, characterized in that: The elastic capsule (202) is a teardrop-shaped elastic sleeve, and the end of the fluid support channel one (204) away from the fluid support channel two (302) is connected to the elastic capsule (202).

6. The latex-free, leak-proof, disposable sterile urinary catheter according to claim 1, characterized in that: The outer surface of the mid-section ultra-soft pipe (301) is wrapped with a mid-section outer hydrophilic coating (303), and the outer surface of the spiral skeleton (304) is wrapped with a skeleton superhydrophobic coating (305).

7. The latex-free, leak-proof, disposable sterile urinary catheter according to claim 1, characterized in that: Multiple silver ion capsules (308) are uniformly fixedly connected to the inner wall of the spiral groove (306), and the silver ion capsules (308) are embedded and fixed in the inner cavity of the negatively charged nano-coating (307).

8. The latex-free, leak-proof, disposable sterile urinary catheter according to claim 1, characterized in that: The external connector (4) includes a urine drainage connector (401) that is connected to the middle section of the ultra-soft pipe (301). The urine drainage connector (401), the rigid pipe (201), and the middle section of the ultra-soft pipe (301) form a complete circular connecting pipe with the same axis.

9. A latex-free, leak-proof, disposable sterile urinary catheter according to claim 1, characterized in that: The outer surface of the middle section of the ultra-soft pipe (301) is fixedly connected with an outer sleeve (402), which is an annular sleeve.

10. A latex-free, leak-proof, disposable sterile urinary catheter according to claim 9, characterized in that: The end of the fluid support channel 2 (302) away from the fluid support channel 1 (204) is connected to the external connector (4), and the outer surface of the external sleeve (402) is connected to the water injection connector (403).

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