Multi-layered ultrafine nanofiber aseptic barrier composite packaging material, preparation method and application

Abstract

The present invention belongs to the field of aseptic packaging materials, and particularly relates to a multi-layer ultra-fine nanofiber aseptic barrier composite packaging material, a preparation method and an application thereof. The method specifically includes six steps: (1) front surface treatment of the support substrate layer, (2) application of hot melt adhesive, (3) preparation of the porous ultra-fine fiber layer, (4) preparation of the hydrophobic ultra-fine fiber layer, (5) back surface treatment of the support substrate layer, and (6) hot pressing and compounding. The preparation method provided by the present invention has the advantages of simple process, easy operation, no sewage and waste gas discharge, energy conservation and environmental protection, low cost and stable and continuous industrial production. The ultra-fine fiber aseptic barrier system composite packaging material provided by the present invention has excellent mechanical properties, as well as remarkable advantages of waterproof and breathable, bacteria-resistant, antibacterial and barrier to tiny dust particles, and can meet the requirements of medical device aseptic barrier packaging materials.

Description

Technical Field

[0001] The present invention belongs to the field of aseptic packaging materials, and particularly relates to a multi-layer ultra-fine nanofiber aseptic barrier composite packaging material, a preparation method and applications thereof. Background Art

[0002] Every year, millions of patients around the world acquire new infections while being treated in hospitals, and this infection phenomenon is called hospital infection. To prevent hospital infection, hospitals generally adopt measures such as cleaning and disinfection, sterilizing instruments, using an aseptic barrier system to protect medical devices, and reasonably using antibiotics. As an integral part of aseptic medical devices, the aseptic barrier system can greatly reduce the probability of patients acquiring hospital infection due to instruments in hospitals.

[0003] Currently, the main packaging materials for sterilization packaging include coated / laminated paper, DuPont Tyvek, PE, PP, PET, PVC, etc. DuPont Tyvek medical packaging material is a non-woven fabric technology material invented by DuPont scientists in the 1950s of the last century. It is not only strong and durable, compatible with various sterilization methods, but also has excellent microbial barrier performance. Compared with other packaging materials, DuPont Tyvek provides a higher level of aseptic protection for medical devices and medical instruments, and has become a "star material" for sterilization packaging. In large and important medical devices such as intraocular lenses, cardiac catheters, and artificial joint replacements with higher requirements, Tyvek shows unparalleled advantages. However, due to the high technical barriers of the flash spinning technology it uses, DuPont Tyvek has formed a single supply in the packaging of high-end medical devices to date.

[0004] Currently, the medical device packaging materials self-produced in our country are mainly used for the packaging of low-end and disposable medical devices, and have disadvantages such as poor barrier effect, poor waterproof performance, and insufficient air permeability. With the development of the economy and the progress of medical technology and concepts in the medical industry, the use safety of medical devices has gradually been taken seriously by the medical community, and the concept of terminal sterilization has gradually become a general consensus in the industry. With the aging of the population, the increase in the incidence of chronic diseases, and the enhancement of residents' awareness of medical health, the attention to the sterilization packaging of medical devices has increased, which has promoted the continuous expansion of the demand for medical devices and their packaging. Domestic substitution and domestic transcendence have become our goals.

[0005] Ultra-fine fibers have characteristics such as small diameter, large specific surface area, high porosity, softness and comfort, as well as high adsorption and antibacterial properties. The extremely high specific surface area leads to an increase in surface energy and activity, showing specific properties in terms of chemical and physical properties.

[0006] The patent with the publication number of CN 115489187 A discloses a high-strength ultra-fine fiber shielding material, its preparation method and application. Although this patent uses ultra-fine fibers, the preparation method of this patent still has the following technical problems: First, the length of the nanofibers used in this patent is 50 - 200 nm, and the diameter is 3 - 20 nm, and its maximum aspect ratio is only 67. Strictly speaking, it does not belong to the category of nanofibers. In addition, its focus is more on improving the mechanical strength of the material, including complex processes such as homogenization of nanomaterials, addition of nucleating agents, setting of magnetic fields and drying tunnels, while the improvement of its air permeability and waterproofness is not involved. Summary of the Invention

[0007] In view of the above technical problems, the present invention provides a multi-layer ultra-fine nanofiber sterile barrier composite packaging material, its preparation method and application; the multi-layer ultra-fine nanofiber sterile barrier composite packaging material provided by the present invention has excellent mechanical properties, good air permeability and waterproof properties, can block fine dust particles, shield various microorganisms, and is protected from environmental factors; and the preparation method provided by the present invention is safe and easy to operate, with low cost and can be stably and continuously produced.

[0008] In order to achieve the above technical objectives, the present invention provides the following technical solutions:

[0009] A preparation method of a multi-layer ultra-fine nanofiber sterile barrier composite packaging material, the method comprising the following steps:

[0010] (1) Treatment of the support substrate layer: Perform plasma surface treatment on the front surface of the support substrate layer;

[0011] (2) Application of hot melt adhesive: Apply hot melt adhesive on the front surface of the support substrate layer treated in step (1); This step can be operated using a coating machine.

[0012] (3) Preparation of the porous ultra-fine fiber layer: Using the front surface of the support substrate layer treated in step (2) as the receiving substrate, perform air electrospinning with the first polymer spinning solution to prepare a porous ultra-fine fiber layer on the front surface of the support substrate layer;

[0013] The ultra-fine fibers in the porous ultra-fine fiber layer have a diameter of 200 - 1000 nm and a length greater than 10 mm; the porosity of the porous ultra-fine fiber layer is: 90% ± 5%, and the air permeability ≥ 35 mm / s;

[0014] (4) Preparation of the hydrophobic ultra-fine fiber layer: Using the porous ultra-fine fiber layer prepared in step (3) as the receiving substrate, perform air electrospinning with the second polymer spinning solution to prepare a hydrophobic ultra-fine fiber layer above the porous ultra-fine fiber layer; the hydrophobic ultra-fine fiber layer includes hydrophobic ultra-fine fibers and microsphere structures with waterproof properties;

[0015] The diameter of the hydrophobic ultrafine fibers is 30 to 500 nm, and the length is greater than 10 mm; the diameter of the microsphere structure is 1 to 30 microns; the pore diameter of the hydrophobic ultrafine fiber layer is less than 1 micron, and the porosity is 75% ± 5%; the hydrophobic ultrafine fiber layer includes hydrophobic ultrafine fibers and a microsphere structure with enhanced waterproof performance. The surface of the hydrophobic ultrafine fiber layer is a superhydrophobic surface, having good hydrophobicity and waterproof performance; and the hydrophobic ultrafine fiber layer is located on the surface layer, with a finer diameter, a high porosity, and a pore diameter less than 1 micron, making it have a better efficiency of intercepting microparticles and bacteria and a higher specific surface area.

[0016] (5) Perform plasma surface treatment on the reverse side of the support substrate layer;

[0017] (6) Lamination: Laminating the support substrate layer, the porous ultrafine fiber layer, and the hydrophobic ultrafine fiber layer treated in steps (1) to (5) by hot pressing to produce a multilayer ultrafine nanofiber sterile barrier composite packaging material.

[0018] Further, between step (5) and step (6), the following steps are also included:

[0019] (5.1) Using the reverse side of the support substrate layer treated in step (5) as the receiving substrate, repeating steps (2) and (3) to prepare a porous ultrafine fiber layer on the reverse side of the support substrate layer;

[0020] (5.2) Preparation of the hydrophobic ultrafine fiber layer: Using the porous ultrafine fiber layer prepared in step (5.1) as the receiving substrate, repeating step (4) to prepare a hydrophobic ultrafine fiber layer above the porous ultrafine fiber layer.

[0021] Further, in step (3), the first polymer spinning solution is prepared by dissolving a first polymer in a first polymer solvent;

[0022] The first polymer includes one or more of polystyrene, polylactic acid, polycarbonate, polyvinyl carbazole, polyoxymethylene, and poly(lactic acid - glycolic acid) copolymer; the first polymer solvent includes one or more of N,N - dimethylformamide, tetrahydrofuran, dichloromethane, and hexafluoroisopropanol; in the first polymer spinning solution, the mass fraction of the first polymer is 10 to 30%;

[0023] The conditions of the air jet spinning in step (3) are as follows: the injection speed of the spinning solution is 0.2 - 1.0 mL / min, the air pressure is 0.1 - 3 MPa, the running speed of the receiving substrate is 80 - 300 mm / min, the receiving distance is 18 - 60 cm, the temperature is 25 - 60 °C, and the humidity is 50% - 90%. The polymer solution jet is stretched and moves at high speed in the high-pressure and high-speed air flow. During this process, the solvent quickly volatilizes, causing the water vapor in the air to condense on the surface of the jet, forming water droplets. After the fiber dries, a porous surface structure is formed. The speed of solvent volatilization is an important factor affecting the formation of the pore structure. Compared with the electrospinning technology, the air jet spinning technology uses high-pressure and high-speed air flow to stretch the spinning solution to prepare nanofibers, resulting in a much faster volatilization speed of the solvent in the spinning solution, a more intense thermodynamically unstable state, and making it easier to obtain porous fibers. Therefore, when using the first polymer spinning solution for air jet spinning, by controlling the air pressure at 0.1 - 3 MPa, the temperature at 25 - 60 °C, and the humidity at 50% - 90%. Under these conditions, the solvent volatilizes quickly and the environmental humidity is relatively high. Under the action of high-pressure and high-speed air flow, the low-boiling solvent evaporates rapidly to produce nanofibers with a porous structure, thereby increasing its air permeability.

[0024] Furthermore, in step (4), the second polymer spinning solution is prepared by dissolving a second polymer in a second polymer solvent;

[0025] The second polymer includes one or more of polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, fluorinated polyurethane, polypropylene, polyacrylonitrile, polyethylene, vinyl acetate, polyethersulfone, and polydimethylsiloxane; the second polymer solvent includes one or more of N,N-dimethylformamide, tetrahydrofuran, N,N-dimethylacetamide, acetone, dimethyl sulfoxide, chloroform, acetic acid, toluene, and N-methylpyrrolidone; the mass fraction of the second polymer in the second polymer spinning solution is 10 - 30%;

[0026] Specifically, polymer molecular chains form entanglements in solution, having a certain viscosity. When the degree of entanglement is insufficient, the jet cannot remain continuous during air-jet spinning and will break to form beaded structure fibers (i.e., microsphere structures). The solution concentration is the decisive factor affecting the entanglement of molecular chains in solution. When the concentration and viscosity of the spinning solution are low, the entanglement degree of the solution molecular chains is insufficient, the force stretching is uneven, and the molecular chain orientation coordination is inconsistent, resulting in beaded structure fibers. The micro-nano structure on the membrane surface has a great influence on hydrophobicity. For hydrophobic materials, increasing the surface roughness can increase their hydrophobicity. Therefore, when using the second polymer spinning solution for air-jet spinning, the mass fraction of the second polymer in the second polymer spinning solution is 2% - 6% lower than the optimal spinning concentration to produce microsphere structures and increase the roughness of the hydrophobic ultrafine fiber layer, thereby increasing its hydrophobicity; the optimal spinning concentration corresponding to each polymer is different. In the present invention, the optimal spinning concentration refers to the concentration of the corresponding polymer when the spun fibers are fibers with a very uniform diameter. When performing gas-liquid spinning on the second polymer spinning solution, the mass fraction of the second polymer in the second polymer spinning solution is 2% - 6% lower than the optimal spinning concentration of the corresponding second polymer. At this concentration, beaded structure fibers, i.e., microsphere structures, can be obtained.

[0027] The conditions of the air-jet spinning in step (4) are as follows: the injection speed of the spinning solution is 0.2 - 1.0 mL / min, the air pressure is 2 - 5 MPa, the walking speed of the receiving substrate is 80 - 300 mm / min, the receiving distance is 18 - 60 cm, the temperature is 25 - 60 °C, and the humidity is 30% - 50%.

[0028] In steps (3) and (4), the air pressure is a key parameter that needs to be strictly controlled. The air pressure during the process of using the first polymer spinning solution for air-jet spinning to prepare the porous ultrafine fiber layer is relatively small (0.1 - 3 MPa), and relatively thicker fibers can be obtained; the air pressure during the process of using the second polymer spinning solution for air-jet spinning to prepare the hydrophobic ultrafine fiber layer is relatively large (2 - 5 MPa), and relatively thinner fibers can be obtained.

[0029] Furthermore, in step (4), an antibacterial agent is added to the second polymer spinning solution. The added antibacterial agent includes one or more of silver nanoparticles, copper nanoparticles, copper oxide nanoparticles, zinc oxide nanoparticles, titanium dioxide nanoparticles, gold nanoparticles, and antibacterial peptides; the mass of the antibacterial agent is 1% - 10% of the mass of the second polymer.

[0030] Furthermore, both the porous ultrafine fiber layer in step (3) and the hydrophobic ultrafine fiber layer in step (4) are prepared using a double-stage multi-nozzle continuous air-jet spinning device;

[0031] The double-stage multi-nozzle continuous air spinning device includes at least two stages of multi-nozzle spinning units. Each stage of the multi-nozzle spinning unit is composed of a coaxial needle array distributed in a staggered manner. In the coaxial needle array, the number of coaxial needles in each row is 6 to 30, and the number of coaxial needles in each column is 3 to 15;

[0032] The porous ultrafine fiber layer is prepared by using the first multi-nozzle spinning unit of the double-stage multi-nozzle continuous air spinning device, and the hydrophobic ultrafine fiber layer is prepared by using the second multi-nozzle spinning unit;

[0033] Each of the coaxial needles is composed of an inner needle and an outer needle. Preferably, the inner needle of the coaxial needle used in the first-stage multi-nozzle spinning unit is of model 22G, and the outer needle is of model 16G. The inner needle of the coaxial needle used in the second-stage multi-nozzle spinning unit is of model 24G, and the outer needle is of model 17G. The model of the coaxial needle in the present invention is not limited to the above models. The thinner the needle, the finer the obtained fiber, and it can be adjusted according to the actual production situation.

[0034] Compared with other common air spinning devices, the double-stage multi-nozzle continuous air spinning device is characterized by being equipped with multiple stages of needles, which can realize large-scale preparation. The advantage of using multiple stages of needles in the air spinning of the present invention is that coaxial needles are used, that is, a large needle sleeves a small needle. The large needle part is for passing gas, and the internal small needle is for passing spinning solution. The high-speed air flow serves as the driving force for spinning ultrafine fibers from the solution. The shear force induced by the air flow at the gas-liquid interface is used to refine the solution extruded from the needle tip, forming a liquid jet along the flow direction. Subsequently, the air flow effectively helps the solvent to evaporate, thereby obtaining high-quality fibers.

[0035] Further, the conditions for the plasma surface treatment in the step (1) and the step (5) are: treatment time 1 to 20 s, current 0.1 to 5 A, voltage 20 to 150 V;

[0036] In the step (2), hot melt adhesive is applied by means of dot gluing or linear gluing; the hot melt adhesive is one of EVA hot melt adhesive, PUR hot melt adhesive, PO hot melt adhesive, and PSA hot melt adhesive; the melting temperature is 65 to 120 °C; the glue spraying amount is 2.0 to 5.0 g / m 2 Specifically, the methods of dot gluing and linear gluing do not form a layer of hot melt adhesive film, but only have glue locally and do not completely block the pores of the breathable layer, so the air permeability can meet the requirements.

[0037] The support substrate layer in the step (1) is made of one of non-woven fabric, textile fabric, and paper; the raw materials of the non-woven fabric and the textile fabric are one or more of polyethylene terephthalate, polyethylene, polytetrafluoroethylene, nylon 6, polypropylene, polybutene / polybutadiene copolymer, polylactic acid, and cellulose acetate; the raw materials of the paper are at least one of cellulose, polylactic acid, nylon 6, polyethylene, and polypropylene. The support substrate layer mainly plays a supporting role. In terms of comprehensive air permeability and mechanical strength, the non-woven fabric and the textile fabric have better performance; among them, materials such as polyethylene terephthalate, nylon 6, and polypropylene have high strength, good elasticity, and wear resistance.

[0038] Further, in the hot pressing and compounding process in the step (6), at least two groups of pressing rollers are used, the diameter of the pressing rollers is 260 - 600 mm, the pressing force is 1.5 - 150 t, and the hot pressing temperature is 50 - 150 °C.

[0039] A multi-layer ultra-fine fiber sterile barrier composite packaging material, and the multi-layer ultra-fine fiber sterile barrier composite packaging material is a three-layer composite structure or a five-layer composite structure;

[0040] When it is a three-layer composite structure, it includes a support substrate layer, a porous ultra-fine fiber layer, and a hydrophobic ultra-fine fiber layer arranged in sequence;

[0041] When it is a five-layer composite structure, it includes a hydrophobic ultra-fine fiber layer, a porous ultra-fine fiber layer, a support substrate layer, a porous ultra-fine fiber layer, and a hydrophobic ultra-fine fiber layer arranged in sequence;

[0042] The porous ultra-fine fiber layer includes ultra-fine fibers and a porous structure with enhanced air permeability; the diameter of the ultra-fine fibers is 200 - 1000 nm, and the length is greater than 10 mm; the pore diameter of the porous structure is 50 - 100 nm; the porosity of the porous ultra-fine fiber layer is: 90% ± 5%, and the air permeability is ≥ 35 mm / s; the porous ultra-fine fiber layer endows the multi-layer ultra-fine fiber sterile barrier composite packaging material with excellent air permeability performance;

[0043] The hydrophobic ultra-fine fiber layer includes hydrophobic ultra-fine fibers and a microsphere structure with waterproof performance; the diameter of the hydrophobic ultra-fine fiber layer is 30 - 500 nm, and the length is greater than 10 mm; the diameter of the microsphere structure is 1 - 30 microns; the pore diameter of the hydrophobic ultra-fine fiber layer is less than 1 micron, and the porosity is 75% ± 5%; the number of microsphere structures in the hydrophobic ultra-fine fiber layer under a scanning electron microscope × 5.0k field of view is 20 - 50; the hydrophobic ultra-fine fiber layer endows the multi-layer ultra-fine fiber sterile barrier composite packaging material with excellent hydrophobic performance and biological barrier performance; and also has excellent mechanical properties;

[0044] The tensile strength of the multi-layered ultrafine fiber sterile barrier composite packaging material is ≥20 kPa, the hydrostatic pressure is ≥10 kPa, the air permeability is ≥20 mm / s, and the particle filtration efficiency is ≥99.9%.

[0045] An application of a multi-layered ultrafine nanofiber sterile barrier composite packaging material, which applies the multi-layered ultrafine fiber sterile barrier composite packaging material to the fields of medical device packaging and drug packaging.

[0046] The beneficial effects of the present invention are as follows:

[0047] (1) The multi-layered ultrafine nanofiber sterile barrier composite packaging material and its preparation method provided by the present invention adopt a unique method and process route different from the flash evaporation method used by DuPont paper in the past, overcoming the problem of single-source supply, facilitating domestic substitution and surpassing, and being of great significance for supply chain security.

[0048] (2) The preparation method of the multi-layered ultrafine nanofiber sterile barrier composite packaging material provided by the present invention adopts the compounding of a support substrate layer, a porous ultrafine fiber layer and a hydrophobic ultrafine fiber layer, making the obtained composite material light in weight, waterproof, breathable, dust-proof, bacteria-blocking, antibacterial, high-strength, low-dust-producing, easy to print, and having good material adaptability to various sterilization methods, etc., with excellent comprehensive performance, showing unique advantages in medical packaging, and being able to achieve the effects and requirements comparable to DuPont paper in medical device packaging.

[0049] (3) In order to achieve high air permeability of the material, the porous ultrafine fiber layer of the multi-layered ultrafine nanofiber sterile barrier composite packaging material provided by the present invention utilizes characteristics such as the nano-porous structure on the surface of the ultrafine fiber. It has a small diameter and a high porosity, providing rich transport channels for air flow while effectively intercepting fine particles, and can endow the material with good air permeability and high bacteria-blocking characteristics; the hydrophobic ultrafine fiber layer utilizes a hydrophobic material and a micro-nano composite structure to obtain a superhydrophobic surface, having good hydrophobicity and waterproof performance; and the hydrophobic ultrafine fiber layer is located on the surface layer, and the diameter of the ultrafine fibers in the hydrophobic ultrafine fiber layer is finer than that of the ultrafine fibers in the porous ultrafine fiber layer, with a high porosity and a pore diameter less than 1 micron, making it have better efficiency in intercepting microparticles and bacteria, a higher specific surface area, and also a high surface antibacterial and bactericidal efficiency. The support substrate layer selects a material with good mechanical properties, endowing the composite material with overall excellent mechanical properties.

[0050] (4) The preparation method of the multi-layer ultra-fine nanofiber sterile barrier composite packaging material provided by the present invention first uses the plasma surface treatment technology on the support substrate, which not only sterilizes the surface to achieve the effect of inner layer sterility, but also cleans the attached grease and oil stains. Moreover, the plasma surface treatment can modify its surface, increasing the surface adhesion and making its combination with the porous ultra-fine fiber layer more firm. In addition, in order to improve the preparation efficiency and industrialization, the present invention uses a double-stage multi-nozzle continuous air spinning device for spinning. The efficiency of preparing ultra-fine fibers by air spinning is higher than that of the electrospinning method. In addition, in order to prepare ultra-fine fibers with different compositions, structures and properties, two-stage nozzles and different process conditions are adopted. The first-stage multi-nozzle spinning unit used to prepare the porous ultra-fine fiber layer has a thicker coaxial needle head, a smaller air flow pressure, and the prepared ultra-fine fibers are thicker, but the spinning efficiency is high, easy to form pores, and has good air permeability. The second-stage multi-nozzle spinning unit used to prepare the hydrophobic ultra-fine fiber layer has a thinner coaxial needle head and a larger air flow. The prepared ultra-fine fibers are finer, and it is easy to obtain a "bead-fiber" microsphere structure, with a large water osmotic pressure, good hydrophobicity, and good antibacterial properties. And the present invention uses a double-stage multi-nozzle continuous air spinning device, which can realize the large-scale continuous preparation of various raw materials, with high preparation efficiency, simple process and easy operation.

[0051] (5) In the preparation method of the multi-layer ultra-fine nanofiber sterile barrier composite packaging material provided by the present invention, after the hot pressing composite treatment, the bonding strength between the ultra-fine fibers and the support substrate can be effectively improved, and the mechanical properties and stability of the composite material can be further improved. The ultra-fine fiber sterile barrier system composite packaging material provided by the present invention has excellent mechanical properties, as well as the remarkable advantages of waterproof and breathable, bacteria-proof and antibacterial, and blocking tiny dust particles. It can meet the requirements of medical device sterile barrier packaging materials and effectively solve the disadvantages of poor barrier effect, poor waterproof performance and insufficient air permeability of domestic medical device packaging materials.

[0052] (6) Compared with the prior art CN 115489187 A, the present invention takes into account the mechanical strength, air permeability and waterproofness through a simple process. The fibers prepared by air spinning are finer than those in the above patent, reaching the nanometer level, and have better air permeability and filtration efficiency. The "bead-fiber" microsphere structure can not only achieve a better waterproof effect, but also enhance the mechanical strength of the material. The loaded substances such as silver nanoparticles not only provide antibacterial properties, but also play a certain role in improving the mechanical strength. Description of the Drawings

[0053] Figure 1 It is a flow chart of the preparation method of the multi-layer ultra-fine nanofiber sterile barrier composite packaging material in Example 1 of the present invention;

[0054] Figure 2It is a schematic structural diagram of the double-stage multi-nozzle continuous air spinning device in the present invention;

[0055] Figure 3 It is a schematic structural diagram of the ultra-fine fiber aseptic barrier system composite packaging material in Example 1 of the present invention;

[0056] Figure 4 It is a schematic structural diagram of the ultra-fine fiber aseptic barrier system composite packaging material in Example 2 of the present invention;

[0057] Figure 5a -d are respectively schematic diagrams of the microscopic morphology of the porous ultra-fine fiber layer in the ultra-fine fiber aseptic barrier system composite packaging materials in Examples 1-4 of the present invention;

[0058] Figure 6a -d are respectively schematic diagrams of the microscopic morphology of the hydrophobic ultra-fine fiber layer in the ultra-fine fiber aseptic barrier system composite packaging materials in Examples 1-4 of the present invention;

[0059] Figure 7a -d are respectively schematic diagrams of the contact angles of the ultra-fine fiber aseptic barrier system composite packaging materials in Examples 1-4 of the present invention ( Figure 7a corresponding to Example 1, Figure 7b corresponding to Example 2; 7c corresponds to Example 3; 7d corresponds to Example 4);

[0060] Figure 8 It is a schematic diagram of the antibacterial properties of the ultra-fine fiber aseptic barrier system composite packaging materials in Examples 1-4 of the present invention;

[0061] Reference numerals: 1. Support substrate layer; 2. Porous ultra-fine fiber layer; 3. Hydrophobic ultra-fine fiber layer. Detailed implementation manners

[0062] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0063] On the contrary, the present invention covers any alternatives, modifications, equivalent methods and solutions made within the essence and scope of the present invention defined by the claims. Further, in order to enable the public to have a better understanding of the present invention, some specific details are described in detail in the following detailed description of the present invention. Those skilled in the art can fully understand the present invention without the description of these details.

[0064] The test methods described in the following embodiments are all conventional methods unless otherwise specified; the reagents and materials are all obtained from conventional commercial channels or prepared by conventional methods unless otherwise specified.

[0065] Example 1: A preparation method of a multi-layer ultra-fine nanofiber sterile barrier composite packaging material, the method comprising:

[0066] (1) Treatment of the support substrate layer: Plasma surface treatment (current is 1 A, voltage is 50 V) is carried out on the front surface of the polypropylene non-woven fabric for 10 s to obtain a sterile surface;

[0067] (2) Using a gluing machine, 4.0 g / m 2 EVA hot melt adhesive is applied by linear gluing on the surface of the treated support layer, and the melting temperature is 80 °C;

[0068] (3) Preparation of the porous ultra-fine fiber layer: 12% by mass of polylactic acid is added to a mixed solution of dichloromethane and N,N-dimethylformamide with a volume ratio of 9:1, and stirred until a clear solution is obtained to get the first polymer solution; Through the first-stage multi-nozzle spinning unit of the two-stage multi-nozzle continuous air-flow spinning equipment, the first polymer solution is spun with a spinning solution injection speed of 0.5 mL / min, an air flow pressure of 0.5 MPa, a running speed of the receiving substrate of 100 mm / min, a receiving distance of 24 cm, a temperature of 30 °C, and a humidity of 80%, so as to obtain a porous ultra-fine fiber layer;

[0069] (4) Preparation of the hydrophobic ultra-fine fiber layer: 17% by mass of polyurethane is added to a mixed solution of tetrahydrofuran and N,N-dimethylformamide with a volume ratio of 1:1, stirred until a clear solution is obtained, and then 5% by mass of silver nanoparticles relative to polyurethane is added and stirred evenly to get the second polymer solution; Through the first-stage multi-nozzle spinning unit of the two-stage multi-nozzle continuous air-flow spinning equipment, the second polymer solution is spun with a spinning solution injection speed of 0.8 mL / min, an air flow pressure of 3 MPa, a running speed of the receiving substrate of 100 mm / min, a receiving distance of 24 cm, a temperature of 30 °C, and a humidity of 40%, so as to obtain a hydrophobic ultra-fine fiber layer;

[0070] (5) Reverse treatment of the support substrate layer: Plasma surface treatment (current is 1 A, voltage is 50 V) is carried out on the reverse surface of the polypropylene non-woven fabric in step (1) for 10 s, and the above steps (2) to (4) are repeated;

[0071] (6) Lamination: The polypropylene non-woven fabric layer and the multi-layer ultra-fine fiber layer prepared in steps (1) to (5) are tightly laminated by hot pressing with two groups of pressure rollers. Each group of pressure rollers includes two smooth rollers with a diameter of 300 mm, a pressing force of 15 t, and a temperature of 100 °C, so as to obtain Figure 1 A multi-layer ultra-fine fiber sterile barrier system composite packaging material with waterproof and breathable, bacteria-resistant and antibacterial, and high-strength properties as shown.

[0072] Example 2: A preparation method of a multi-layer ultra-fine nanofiber sterile barrier composite packaging material, the method comprising:

[0073] (1) Treatment of the support substrate layer: The front surface of the cellulose paper is subjected to plasma surface treatment (current is 0.2 A, voltage is 20 V), and the treatment time is 20 s to obtain a sterile surface;

[0074] (2) Using a gluing machine, 3.0 g / m 2 PUR hot melt adhesive is applied on the surface of the treated support layer by means of dispensing, and the melting temperature is 100 °C;

[0075] (3) Preparation of the porous ultra-fine fiber layer: 10% by mass of polyoxymethylene is added to a hexafluoroisopropanol solution, and stirred until a clear solution is obtained to get the first polymer solution; the first polymer solution is spun by the first multi-nozzle spinning unit of a two-stage multi-nozzle continuous air-flow spinning device at a spinning solution injection speed of 0.3 mL / min, an air-flow pressure of 0.5 MPa, a running speed of the receiving substrate of 150 mm / min, a receiving distance of 40 cm, a temperature of 40 °C, and a humidity of 70% to obtain a porous ultra-fine fiber layer;

[0076] (4) Preparation of the hydrophobic ultra-fine fiber layer: 10% by mass of polyvinylidene fluoride is added to a mixed solution of tetrahydrofuran and N,N-dimethylformamide with a volume ratio of 3:7, and stirred until a clear solution is obtained, and then 8% by mass of nano-copper oxide relative to polyvinylidene fluoride is added and stirred evenly to obtain the second polymer solution; the second polymer solution is spun by the second multi-nozzle spinning unit of a two-stage multi-nozzle continuous air-flow spinning device at a spinning solution injection speed of 1.0 mL / min, an air-flow pressure of 4 MPa, a running speed of the receiving substrate of 150 mm / min, a receiving distance of 40 cm, a temperature of 40 °C, and a humidity of 40% to obtain a hydrophobic ultra-fine fiber layer;

[0077] (5) Treatment of the reverse side of the support substrate layer: The reverse side of the cellulose paper in step (1) is subjected to plasma surface treatment (current is 0.2 A, voltage is 20 V), and the treatment time is 20 s;

[0078] (6) Lamination: The cellulose paper layer and the multi-layer ultra-fine fiber layer prepared in steps (1) to (5) are tightly laminated by means of hot pressing with two sets of pressing rollers, and each set of pressing rollers includes two smooth rollers with a diameter of 400 mm, a pressing force of 20 t, and a temperature of 90 °C, thereby obtaining Figure 2 a multi-layer ultra-fine fiber sterile barrier system composite packaging material with waterproof and breathable, bacteria-resistant and antibacterial, and high-strength properties as shown.

[0079] Example 3: A method for preparing a multi-layer ultra-fine nanofiber sterile barrier composite packaging material, the method comprising:

[0080] (1) Treatment of the support substrate layer: Plasma surface treatment (current 3A, voltage 80V) is performed on the front surface of a nylon 6 textile fabric for 10 s to obtain a sterile surface;

[0081] (2) Using a coating machine, 5.0 g / m 2 PO hot melt adhesive is applied by means of line gluing on the surface of the treated support layer, and the melting temperature is 90 °C;

[0082] (3) Preparation of the porous ultra-fine fiber layer: 15% by mass of polycarbonate is added to dichloromethane solution, and stirred until a clear solution is obtained to get a first polymer solution; The first polymer solution is spun by the first-stage multi-nozzle spinning unit of a two-stage multi-nozzle continuous air-flow spinning device at a spinning solution injection speed of 0.2 mL / min, an air flow pressure of 1.0 MPa, a running speed of the receiving substrate of 100 mm / min, a receiving distance of 30 cm, a temperature of 30 °C, and a humidity of 60% to obtain a porous ultra-fine fiber layer;

[0083] (4) Preparation of the hydrophobic ultra-fine fiber layer: 25% by mass of polyethersulfone is added to N,N-dimethylformamide solution, stirred until a clear solution is obtained, and then 8% by mass of nano-copper oxide relative to polyurethane is added and stirred evenly to obtain a second polymer solution; The second polymer solution is spun by the second-stage multi-nozzle spinning unit of a two-stage multi-nozzle continuous air-flow spinning device at a spinning solution injection speed of 1.0 mL / min, an air flow pressure of 3 MPa, a running speed of the receiving substrate of 100 mm / min, a receiving distance of 30 cm, a temperature of 30 °C, and a humidity of 50% to obtain a hydrophobic ultra-fine fiber layer;

[0084] (5) Treatment of the reverse side of the support substrate layer: Plasma surface treatment (current 3A, voltage 80V) is performed on the reverse side of the nylon 6 textile fabric in step (1) for 10 s, and the above steps (2) to (4) are repeated;

[0085] (6) Lamination: The nylon 6 textile fabric layer and the multi-layer ultra-fine fiber layer prepared in steps (1) to (5) are tightly laminated by means of hot pressing with two groups of press rollers. Each group of press rollers includes two smooth rollers with a roller diameter of 200 mm, a pressing force of 10 t, and a temperature of 90 °C, thereby obtaining a multi-layer ultra-fine fiber sterile barrier system composite packaging material with waterproof and breathable, bacteria-resistant and antibacterial, and high-strength properties.

[0086] Example 4: A method for preparing a multi-layer ultra-fine nanofiber sterile barrier composite packaging material, the method comprising:

[0087] (1) Treatment of the supporting substrate layer: The front side of the polyethylene paper is subjected to plasma surface treatment (current: 0.5 A, voltage: 25 V) for 10 s to obtain a sterile surface;

[0088] (2) Using a gluing machine, 3.0 g / m 2 PSA hot melt adhesive is applied on the surface of the above-treated support layer by means of dispensing, and the melting temperature is 110 °C;

[0089] (3) Preparation of the porous ultrafine fiber layer: 12% by mass of polylactic acid is added to a mixed solution of dichloromethane and N,N-dimethylformamide with a volume ratio of 9:1, and stirred until a clear solution is obtained to get the first polymer solution; The first polymer solution is spun by the first-stage multi-nozzle spinning unit of a two-stage multi-nozzle continuous air flow spinning device with a spinning solution injection speed of 0.3 mL / min, an air flow pressure of 0.5 MPa, a running speed of the receiving substrate of 200 mm / min, a receiving distance of 35 cm, a temperature of 25 °C, and a humidity of 80% to obtain a porous ultrafine fiber layer;

[0090] (4) Preparation of the hydrophobic ultrafine fiber layer: 20% by mass of fluorinated polyurethane is added to a mixed solution of tetrahydrofuran and N,N-dimethylformamide with a volume ratio of 1:1, and stirred until a clear solution is obtained, and then 2% by mass of antibacterial peptide relative to the polyurethane is added and stirred evenly to get the second polymer solution; The second polymer solution is spun by the second-stage multi-nozzle spinning unit of a two-stage multi-nozzle continuous air flow spinning device with a spinning solution injection speed of 1.0 mL / min, an air flow pressure of 5 MPa, a running speed of the receiving substrate of 200 mm / min, a receiving distance of 35 cm, a temperature of 25 °C, and a humidity of 40% to obtain a hydrophobic ultrafine fiber layer;

[0091] (5) Treatment of the reverse side of the supporting substrate layer: The reverse side of the polyethylene paper in step (1) is subjected to plasma surface treatment (current: 0.5 A, voltage: 25 V) for 10 s;

[0092] (6) Lamination: The polyethylene paper and the multi-layer ultrafine fiber layers prepared in steps (1) to (5) are tightly laminated by means of hot pressing with two groups of pressure rollers. Each group of pressure rollers includes two smooth rollers with a diameter of 350 mm, a pressing force of 30 t, and a temperature of 110 °C, thereby obtaining a multi-layer ultrafine fiber sterile barrier system composite packaging material with waterproof, breathable, bacteriostatic, antibacterial, and high-strength properties.

[0093] The characteristic indexes of Examples 1-4 were tested respectively, and the test results are shown in Table 1:

[0094] Table 1 Test Results of the Characteristic Indexes of Examples 1-4

[0095]

[0096] In addition, the microscopic morphologies, contact angles, and antibacterial properties of Examples 1-4 are shown in FIGS. 5-7. FIGS. 5 and 6 are schematic diagrams of the microscopic morphologies of the porous ultrafine fiber layer and the hydrophobic ultrafine fiber layer in Examples 1-4, respectively. It can be seen that the porous ultrafine fiber layer all exhibits a porous structure, which helps to improve the air permeability of the present invention. For the hydrophobic ultrafine fiber layer, an obvious "bead-fiber" microsphere structure is shown in Example 4, which helps to enhance the waterproof property.

[0097] FIG. 7 is a schematic diagram of the contact angle of the ultrafine fiber sterile barrier system composite packaging material in Examples 1-4 of the present invention. It can be seen that the packaging material has good waterproof property, and in particular, the waterproof property of Example 4 with a microsphere-fiber structure is the best.

[0098] Figure 8 It is a schematic diagram of the antibacterial property of the ultrafine fiber sterile barrier system composite packaging material in Examples 1-4 of the present invention. It can be seen that the packaging material exhibits excellent antibacterial property and can effectively protect medical devices, etc. from bacterial infection.

[0099] The multi-layer ultrafine nanofiber sterile barrier composite packaging material provided by the present invention has excellent mechanical properties, good air permeability and waterproof property, can block fine dust particles, shield various microorganisms from environmental factors, and at the same time has excellent bacteria-blocking property and antibacterial property, and can effectively solve the disadvantages of poor barrier effect, poor waterproof property, insufficient air permeability, etc. of domestic medical device packaging materials. The preparation method is safe and easy to operate, with low cost and can be stably and continuously produced. It has the characteristics of waterproof, breathable, bacteria-blocking, antibacterial, high strength, dust-proof, etc.

[0100] The above description shows and describes several preferred embodiments of the present application. However, as mentioned above, it should be understood that the present application is not limited to the form disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be changed within the scope of the application concept described herein through the above teachings or the technology or knowledge in related fields. And the changes and alterations made by those skilled in the art that do not depart from the spirit and scope of the present application shall all be within the protection scope of the appended claims of the present application.

Claims

1. A preparation method of a multi-layered ultra-fine nanofiber sterile barrier composite packaging material, characterized in that, The method includes the following steps: (1) Front surface treatment of the support substrate layer: performing plasma surface treatment on the front surface of the support substrate layer; (2) Applying hot melt adhesive: applying hot melt adhesive to the front surface of the support substrate layer treated in step (1); (3) Preparation of the porous ultrafine fiber layer: using the front surface of the support substrate layer treated in step (2) as the receiving substrate, performing air jet spinning with the first polymer spinning solution to prepare a porous ultrafine fiber layer on the front surface of the support substrate layer; the first polymer spinning solution is prepared by dissolving a first polymer in a first polymer solvent; the first polymer includes one or more of polystyrene, polylactic acid, polycarbonate, polyvinyl carbazole, polyoxymethylene, and poly(lactic acid - glycolic acid) copolymer; The ultrafine fibers in the porous ultrafine fiber layer have a diameter of 200 - 1000 nm and a length greater than 10 mm; the porosity of the porous ultrafine fiber layer is: 90% ± 5%, and the air permeability is ≥ 35 mm / s; (4) Preparation of the hydrophobic ultrafine fiber layer: using the porous ultrafine fiber layer prepared in step (3) as the receiving substrate, performing air jet spinning with the second polymer spinning solution to prepare a hydrophobic ultrafine fiber layer above the porous ultrafine fiber layer; the hydrophobic ultrafine fiber layer includes hydrophobic ultrafine fibers and microsphere structures with waterproof properties; an antibacterial agent is added to the second polymer spinning solution; the second polymer spinning solution is prepared by dissolving a second polymer in a second polymer solvent; the second polymer includes one or more of polytetrafluoroethylene, fluorinated polyurethane, polypropylene, polyacrylonitrile, polyethylene, vinyl acetate, polyethersulfone, and polydimethylsiloxane; The hydrophobic ultrafine fibers have a diameter of 30 - 500 nm and a length greater than 10 mm; the diameter of the microsphere structure is 1 - 30 microns; the pore diameter of the hydrophobic ultrafine fiber layer is less than 1 micron, and the porosity is 75% ± 5%; (5) Back surface treatment of the support substrate layer: performing plasma surface treatment on the back surface of the support substrate layer; (6) Lamination: laminating the support substrate layer, the porous ultrafine fiber layer, and the hydrophobic ultrafine fiber layer treated in steps (1) - (5) by hot pressing to prepare a multilayer ultrafine nanofiber sterile barrier composite packaging material; In step (3), the air flow pressure is 0.1 - 3 MPa, the temperature is 25 - 60 °C, and the humidity is 50% - 90%; In step (4), the air flow pressure is 2 - 5 MPa, the temperature is 25 - 60 °C, and the humidity is 30% - 50%.

2. The preparation method of a multi-layer ultra-fine nanofiber sterile barrier composite packaging material according to claim 1, wherein Between step (5) and step (6), the following steps are further included: (5.1) Using the back surface of the support substrate layer treated in step (5) as the receiving substrate, repeating steps (2) and (3) to prepare a porous ultrafine fiber layer on the back surface of the support substrate layer; (5.2) Preparation of the hydrophobic ultrafine fiber layer: using the porous ultrafine fiber layer prepared in step (5.1) as the receiving substrate, repeating step (4) to prepare a hydrophobic ultrafine fiber layer above the porous ultrafine fiber layer.

3. The preparation method of a multi-layer ultra-fine nanofiber sterile barrier composite packaging material according to claim 1 or 2, characterized in that, In step (3), the first polymer solvent includes one or more of N, N-dimethylformamide, tetrahydrofuran, dichloromethane, and hexafluoroisopropanol; in the first polymer spinning solution, the mass fraction of the first polymer is 10% to 30%. The conditions for air spinning in step (3) are as follows: the injection speed of the spinning solution is 0.2 to 1.0 mL / min, the running speed of the receiving substrate is 80 to 300 mm / min, and the receiving distance is 18 to 60 cm.

4. The preparation method of a multi-layer ultra-fine nanofiber sterile barrier composite packaging material according to claim 1 or 2, characterized in that, In step (4), the second polymer solvent includes one or more of N, N-dimethylformamide, tetrahydrofuran, N, N-dimethylacetamide, acetone, dimethyl sulfoxide, chloroform, acetic acid, toluene, and N-methylpyrrolidone. The mass fraction of the second polymer in the second polymer spinning solution is 10% to 30%. The conditions for air spinning in step (4) are as follows: the injection speed of the spinning solution is 0.2 to 1.0 mL / min, the running speed of the receiving substrate is 80 to 300 mm / min, and the receiving distance is 18 to 60 cm.

5. The preparation method of a multi-layer ultra-fine nanofiber sterile barrier composite packaging material according to claim 4, characterized in that, In step (4), the added antibacterial agent includes one or more of silver nanoparticles, copper nanoparticles, copper oxide nanoparticles, zinc oxide nanoparticles, titanium dioxide nanoparticles, gold nanoparticles, and antibacterial peptides; the mass of the antibacterial agent is 1% to 10% of the mass of the second polymer.

6. The preparation method of a multi-layer ultra-fine nanofiber sterile barrier composite packaging material according to claim 1 or 2, characterized in that, Both the porous ultrafine fiber layer in step (3) and the hydrophobic ultrafine fiber layer in step (4) are prepared by a two-stage multi-nozzle continuous air spinning device. The two-stage multi-nozzle continuous air spinning device includes at least two-stage multi-nozzle spinning units. Each multi-nozzle spinning unit is composed of a coaxial needle array with staggered distribution. In the coaxial needle array, the number of coaxial needles in each row is 6 to 30, and the number of coaxial needles in each column is 3 to 15. The porous ultrafine fiber layer is prepared by using the first-stage multi-nozzle spinning unit of the two-stage multi-nozzle continuous air spinning device, and the hydrophobic ultrafine fiber layer is prepared by using the second-stage multi-nozzle spinning unit. Each coaxial needle is composed of an inner needle and an outer needle. The inner needle model of the coaxial needle used in the first-stage multi-nozzle spinning unit is 22G, and the outer needle model is 16G; the inner needle model of the coaxial needle used in the second-stage multi-nozzle spinning unit is 24G, and the outer needle model is 17G.

7. The preparation method of a multi-layer ultra-fine nanofiber sterile barrier composite packaging material according to claim 1 or 2, characterized in that, The conditions for plasma surface treatment in steps (1) and (5) are as follows: the treatment time is 1 to 20 s, the current is 0.1 to 5 A, and the voltage is 20 to 150 V. In the step (2), hot melt adhesive is applied by dotting or linear sizing; the hot melt adhesive is one of EVA hot melt adhesive, PUR hot melt adhesive, PO hot melt adhesive, and PSA hot melt adhesive; the melting temperature is 65-120 °C; the glue spraying amount is 2.0-5.0 g / m 2 ; The support substrate layer in step (1) is made of one of non-woven fabric, textile fabric, and paper; the raw materials of the non-woven fabric and the textile fabric are one or more of polyethylene terephthalate, polyethylene, polytetrafluoroethylene, nylon 6, polypropylene, polybutene / polybutadiene copolymer, polylactic acid, and cellulose acetate; the raw materials of the paper are at least one of cellulose, polylactic acid, nylon 6, polyethylene, and polypropylene.

8. The preparation method of a multi-layered ultra-fine nanofiber sterile barrier composite packaging material according to claim 1, characterized in that, In the step (6), at least two groups of pressing rollers are used in the hot pressing and compounding process. The diameter of the pressing rollers is 260-600 mm, the pressing force is 1.5-150 t, and the hot pressing temperature is 50-150 °C.

9. A multi-layer ultra-fine fiber sterile barrier composite packaging material, prepared by using the preparation method described in any one of claims 1 to 8, characterized in that, The multi-layer ultra-fine fiber sterile barrier composite packaging material is a three-layer composite structure or a five-layer composite structure; When it is a three-layer composite structure, it includes a support substrate layer, a porous ultra-fine fiber layer, and a hydrophobic ultra-fine fiber layer arranged in sequence; When it is a five-layer composite structure, it includes a hydrophobic ultra-fine fiber layer, a porous ultra-fine fiber layer, a support substrate layer, a porous ultra-fine fiber layer, and a hydrophobic ultra-fine fiber layer arranged in sequence; The diameter of the ultra-fine fibers in the porous ultra-fine fiber layer is 200-1000 nm, and the length is greater than 10 mm; the porosity of the porous ultra-fine fiber layer is: 90%±5%, and the air permeability is ≥35 mm / s The hydrophobic ultra-fine fiber layer includes hydrophobic ultra-fine fibers and microsphere structures with waterproof properties; the diameter of the hydrophobic ultra-fine fiber layer is 30-500 nm, and the length is greater than 10 mm; the diameter of the microsphere structure is 1-30 microns; the pore diameter of the hydrophobic ultra-fine fiber layer is less than 1 micron, and the porosity is 75%±5%; The multi-layer ultra-fine fiber sterile barrier composite packaging material has a tensile strength ≥ 20 kPa, a hydrostatic pressure ≥ 10 kPa, an air permeability ≥ 20 mm / s, and a particle filtration efficiency ≥ 99.9%.

10. The application of a multi-layered ultrafine nanofiber sterile barrier composite packaging material according to claim 9, characterized in that, The multi-layer ultra-fine fiber sterile barrier composite packaging material is applied to the fields of medical device packaging and drug packaging.

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