Environment-friendly steam-sterilization-resistant medical packaging bag

Abstract

The invention discloses an environment-friendly steam-sterilization-resistant medical packaging bag which is formed by connecting an upper sheet and a lower sheet in a three-edge hot-pressing sealing mode, a bag opening is formed in the non-sealing connection portion, the portion opposite to the bag opening is a bag bottom, the upper sheet is a PP easy-to-uncover film, and the lower sheet is a PP easy-to-uncover film. The lower sheet is formed by compounding SMMS non-woven fabric and a PP film through a dispersed point-shaped hot pressing process, the PP film faces the inner side of the bag body, and a plurality of micropores formed through laser processing are evenly distributed in the PP film. According to the medical packaging bag, the medical packaging bag is resistant to steam sterilization, breathable, capable of blocking bacteria, clean in stripping, environmentally friendly and recyclable.

Description

Technical Field

[0001] The present invention relates to the technical field of medical packaging materials, and more particularly to an environmentally friendly medical packaging bag resistant to steam sterilization. Background Art

[0002] In the field of medical device sterilization packaging, steam sterilization (such as moist heat sterilization) is one of the most commonly used sterilization methods. The packaging material needs to meet the following core requirements: resistant to steam sterilization: able to withstand high temperatures (usually 121°C - 134°C) and high-pressure environments without breakage, deformation or material degradation; breathable and bacteria-proof: allowing steam to penetrate during sterilization to kill microorganisms, while preventing external microorganisms from invading after sterilization; clean peeling: no fibers or debris fall off when opening the package to avoid secondary contamination of the device.

[0003] However, traditional medical sterilization packaging bags have the following deficiencies: a single material is difficult to meet the requirements of breathability and bacteria-proof at the same time. For example, non-woven fabric has good breathability but cannot achieve clean peeling after heat sealing and ironing, and plastic film has strong bacteria-proof property but poor breathability; the composite structure lacks environmental friendliness, and some materials are not recyclable or release harmful substances after sterilization.

[0004] Therefore, there is an urgent need for a medical packaging bag with an optimized structure that takes into account sterilization resistance, breathability and bacteria-proof, clean peeling and environmental protection requirements. Summary of the Invention

[0005] The purpose of the present invention is to provide an environmentally friendly medical packaging bag resistant to steam sterilization, so as to solve the problem that the medical packaging bags in the prior art are difficult to meet the requirements of sterilization resistance, breathability and bacteria-proof, clean peeling and environmental protection at the same time.

[0006] According to the present invention, there is provided an environmentally friendly medical packaging bag resistant to steam sterilization. The medical sterilization packaging bag is formed by thermally pressing and sealing the upper sheet and the lower sheet on three sides. The un-sealed part forms a bag mouth, and the part opposite to the bag mouth is the bag bottom. It is characterized in that the upper sheet is a PP easy-peel film, and the lower sheet is composed of SMMS non-woven fabric and a PP film compounded by a dispersed dot-shaped thermal pressing process. The PP film faces the inner side of the bag body, and the PP film has a number of micropores formed by laser processing and evenly distributed thereon.

[0007] Preferably, the SMMS non-woven fabric and the PP film are combined by a thermal pressing process to form a number of dispersed pressing and ironing points. The diameter of the pressing and ironing points is 1 - 2 mm, and the distance between adjacent pressing and ironing points is 15 - 35 mm.

[0008] Preferably, the conditions of the dispersed dot-shaped thermal pressing process are: temperature 170 - 200°C, pressure 0.3 - 0.5 MPa, and sealing and ironing time 1.5 - 3.5 s.

[0009] Preferably, the pore diameter of the micro-holes formed by laser processing on the PP film is 100 - 500 μm, and the pore spacing is 2 - 5 mm.

[0010] Preferably, the density of the micro-holes formed by laser processing on the PP film is 6 - 25 holes / cm², meeting the gas exchange requirements during steam sterilization.

[0011] Preferably, the conditions of the hot pressing process for the upper sheet and the lower sheet are: temperature 170 - 220 °C, pressure 0.3 - 0.5 MPa, and sealing and ironing time 1.5 - 4 s.

[0012] Preferably, the peeling force between the PP film and the PP easy-peeling film is controlled at 2.0 - 7.0 N / 15 mm, meeting the requirements of medical clean peeling.

[0013] Preferably, the thickness of the PP easy-peeling film is 60 - 80 μm, and the surface tension is 30 - 35 mN / m.

[0014] Preferably, the grammage of the SMMS non-woven fabric is 30 - 40 g / m², and the thickness of the PP film is 25 - 35 μm.

[0015] Preferably, the bag bottom has a V-shaped structure.

[0016] The present invention aims to provide an environmentally friendly steam sterilization-resistant (EFP structure) medical packaging bag, which meets the multiple performance requirements of medical steam sterilization packaging through material combination and structural design.

[0017] Among them, the upper sheet is also called the easy-peeling clean peeling layer, and is made of a PP easy-peeling film (modified polypropylene film, surface tension 30 - 35 mN / m), which has the characteristics of low peeling force, good transparency, and can achieve clean peeling after being sealed and ironed with the PP film of the lower sheet. It should be understood that the main raw materials of the PP easy-peeling film and the PP film are both PP (polypropylene), and are processed into films by blow molding or casting, with slight differences between them. The difference lies in that when the PP easy-peeling film is processed into a film, some special additives such as slip agents and anti-blocking agents are added, or it undergoes special surface treatment to change the surface properties of the film, reduce the adhesion between the film and the adherend, and make it have the easy-peeling property.

[0018] The lower sheet, also known as the steam-sterilization-resistant breathable bacteria-blocking layer, is composed of SMMS non-woven fabric and PP film, which are composite by dispersed dot hot pressing. The SMMS non-woven fabric faces the outside of the bag body, and the PP film faces the inside of the bag body. Among them, the SMMS non-woven fabric is a four-layer (spunbond-meltblown-meltblown-spunbond) non-woven fabric made of polypropylene (PP) as raw material, with excellent microbial barrier function, which can effectively block the penetration of bacteria and other microorganisms, and at the same time has a soft texture and is resistant to heat and humidity. The PP film uses a food-grade polypropylene film, and uniform micropores are formed by laser processing. Preferably, the pore diameter is 100-500μm, the pore spacing is 2-5mm, and the micropore density is 6-25 pieces / cm², which meets the gas exchange requirements during the steam sterilization process.

[0019] The SMMS non-woven fabric and the PP film are combined by a hot pressing process. The hot pressing points are in a dispersed dot shape, the diameter of the hot pressing points is 1-2mm, and the spacing is 15-35mm. The conditions of the hot pressing process are: temperature 170-200°C, pressure 0.3-0.5MPa, and the sealing and ironing time is 1.5-3.5s, which not only ensures the firm bonding of the two layers of materials, but also retains the air permeable channel between the non-woven fabric and the PP film.

[0020] The inventive point of the present invention mainly lies in that for the first time, a technical solution is proposed to perform dispersed dot hot pressing on the SMMS non-woven fabric and the PP film through a hot pressing device, and then hot pressing and sealing the composite film with the PP easy-peel film to form an environmentally friendly steam-sterilization-resistant medical packaging bag, which can meet the multiple performance requirements of medical steam sterilization packaging at the same time. According to the present invention, the PP easy-peel film of the upper sheet and the PP film of the lower sheet are hot pressed and sealed to form a packaging bag with three edges closed and one edge open. The opening is the bag mouth of the packaging bag, and the other side opposite to the bag mouth is the V-shaped hot pressing and bonding part as the bag bottom. The edge of the bag bottom is open and not sealed as the opening for peeling and opening when using after packaging items. This medical packaging bag is not only resistant to steam sterilization, but also breathable and bacteria-blocking, and can be cleanly peeled. Most importantly, all materials are polypropylene-based recyclable materials, which are environmentally friendly and recyclable.

[0021] Such an environmentally friendly steam-sterilization-resistant medical packaging bag provided by the present invention has the following remarkable beneficial effects compared with the prior art: 1) Steam-sterilization-resistant: Both the SMMS non-woven fabric and the PP film have excellent high-temperature resistance (melting point ≥ 165°C), can withstand steam sterilization (134°C, 30 minutes), have good air permeability, high sealing and peeling force, and the packaging bag has strong load-bearing capacity, and it is not easy to burst during steam sterilization.

[0022] 2) Breathable and bacteria-blocking: The laser micropores of the PP film allow steam to penetrate, and the dense structure of the SMMS non-woven fabric has good microbial barrier performance, combining to achieve the balance of "breathable but not bacteria-penetrating".

[0023] 3) Clean peeling: When peeling the sealing and ironing interface between the PP easy-peeling film on the B side and the PP film on the A side, there is no debris or fiber shedding, and the peeling force is controlled at 2.0 - 7.0 N / 15 mm, meeting the requirements of medical clean peeling.

[0024] 4) Environmentally friendly and recyclable: All materials are polypropylene-based recyclable materials, free of halogens and heavy metals, meeting the development trend of green medical packaging.

[0025] In summary, the present invention provides a medical packaging bag that is steam sterilization resistant, breathable and bacteria-barrier, clean peeling, and environmentally friendly and recyclable. Description of the Drawings

[0026] Figure 1 It is a plan view of a medical packaging bag according to a preferred embodiment of the present invention; Figure 2 As shown in Figure 1 It is a cross-sectional view of the medical packaging bag shown; Figure 3 It is a structural diagram of the lower sheet; Among them, the meanings of the reference numerals are as follows: 10: Upper sheet (PP easy-peeling film); 20: Lower sheet; 21: SMMS non-woven fabric; 22: PP film; 23: Ironing point; 24: Micropores; 30: Side sealing and ironing connection; 40: Bag mouth; 50: Bottom sealing and ironing connection; 60: Opening seal. Detailed Embodiments

[0027] The following further describes the present invention in conjunction with specific embodiments. It should be understood that the following embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. Unless otherwise specified, the technical means used in the embodiments are conventional operations in the art or experimental methods recommended by instrument and equipment manufacturers. The reagents and materials used in the embodiments can be obtained from commercial sources unless otherwise specified.

[0028] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0029] Embodiment 1 Material Preparation The upper sheet 10 is made of PP peelable film with a thickness of 70 μm and a surface tension of 35 mN / m. Its trade name is "polypropylene (PP) peelable film" and it is purchased from Fujian Kailong Packaging Co., Ltd.

[0030] The lower sheet 20 is composed of SMMS (spunbond - meltblown - meltblown - spunbond) non - woven fabric 21 (with a gram weight of 35 g / m²) and PP film 22 (with a thickness of 30 μm). The trade name of PP film 22 is "polypropylene (PP) film" and it is purchased from Fujian Kailong Packaging Co., Ltd.

[0031] A number of uniformly distributed micro - holes 24 with a pore diameter of 80 μm, a pore spacing of 5 mm, and a density of 6 per cm² are pre - processed on the PP film 22 by a laser machine. Then, the SMMS non - woven fabric 21 and the PP film 22 are laminated together, and dispersed dot - type hot - pressing is carried out through a hot - pressing device to form a number of dispersed hot - pressed points 23. The diameter of the hot - pressed points 23 is 2 mm, the spacing between the hot - pressed points is 25 mm, the sealing and ironing temperature is 185 °C, the pressure is 0.4 MPa, and the sealing and ironing time is 2.5 s.

[0032] Preparation of the packaging bag The upper sheet (PP peelable film) 10 and the PP film 22 of the lower sheet 20 (with the SMMS non - woven fabric 21 facing outwards) are hot - pressed and sealed on three sides by a heat - sealer to form side - sealing joints 30 and bottom - bag sealing joints 50. The process conditions for hot - pressing are: temperature 195 °C, pressure 0.4 MPa, time 2.5 s, sealing edge width 10 mm. One side is left unsealed as the bag mouth 40, and the part opposite to the bag mouth 40 is a V - shaped bag bottom. The edge of this bag bottom is open and unsealed as the opening seal 60, which is convenient for peeling when the packaged items are opened after sterilization.

[0033] After loading the items, the bag mouth 40 is hot - pressed and sealed again, with a temperature of 195 °C, a pressure of 0.4 MPa, a time of 3 s, and a sealing edge width of 10 mm to form a sealed packaging bag.

[0034] Performance testing Sterilization resistance: After being sterilized by 134 °C steam three times, the material has no delamination or breakage, and the micro - pore structure remains intact; Air permeability: Tested by the differential pressure method, the air permeability rate ≥ 500 mL / (m²·s) (test pressure 1 kPa); Bacterial barrier property: Using the microbial challenge test, the bacterial suspension (Bacillus subtilis) cannot penetrate the B - side material; Clean peeling: The peeling force is 4.5 N / 15 mm, and there is no debris residue at the interface after peeling, meeting the YY / T 0698.5 - 2009 standard.

[0035] Example 2 (optimizing micro - pore parameters) Material preparation: For the PP film 22 of the lower sheet 20, laser processing is used to create micropores (pore diameter 300 μm, pore spacing 3 mm, density 15 per cm²), and other parameters are the same as in Example 1.

[0036] Performance test: Air permeability: The air permeability rate is increased to 850 mL / (m²·s), and the steam penetration efficiency is improved.

[0037] Bacterial resistance: There is still no penetration in the microbial challenge test.

[0038] Peeling situation: The peeling force is 5.2 N / 15 mm, and the peeling is clean without residue.

[0039] Example 3 (High air permeability design) Material preparation: For the PP film 22 of the lower sheet 20, the micropore diameter is increased to 500 μm, the pore spacing is 2 mm, and the density is 25 per cm². Other parameters are the same as in Example 1.

[0040] Performance test: Air permeability: The air permeability rate is increased to 1200 mL / (m²·s), the sterilization efficiency is significantly improved, and the risk of bag bursting is reduced.

[0041] Bacterial resistance: The microbial barrier is still effective.

[0042] Peeling situation: The peeling force is 6.5 N / 15 mm, and it does not affect the clean peeling.

[0043] Comparative Example 1 (Too small micropore diameter) Material preparation: For the PP film 22 of the lower sheet 20, the micropore diameter is 50 μm, the pore spacing is 5 mm, and the density is 6 per cm².

[0044] Test results: Air permeability: The air permeability rate is only 180 mL / (m²·s), the steam penetration is insufficient, affecting the sterilization effect, and at the same time increasing the risk of bag bursting.

[0045] Bacterial resistance: Effective, but there is a functional imbalance (insufficient air permeability becomes the main defect).

[0046] Peeling situation: The peeling force is 3.5 N / 15 mm, and it can be peeled cleanly.

[0047] It can be seen that when the micropore diameter is too small, although it does not affect the clean peeling, neither the air permeability nor the bacterial resistance can meet the requirements.

[0048] Comparative Example 2 (Too large micropore diameter) Material preparation: For the PP film 22 of the lower sheet 20, the micropore diameter is 600 μm, the pore spacing is 2 mm, and the density is 30 per cm².

[0049] Test results: Air permeability: The air permeability rate exceeds 1500 mL / (m²·s), and the air permeability is excellent.

[0050] Bacteriostatic property: Effective.

[0051] Peeling condition: The peeling force is 8.0 N / 15 mm. Fibers appear during peeling, affecting clean peeling.

[0052] It can be seen that when the micropore diameter is too large, it may affect clean peeling.

[0053] Example 4 (Low-temperature heat-sealing process) Material preparation: The heat-sealing temperature of the upper sheet 10 and the lower sheet 20 is set at 170 °C, the pressure is 0.3 MPa, and the time is 4 s.

[0054] Performance test: Peeling condition: The peeling force is 2.0 N / 15 mm. The peeling is smooth but there is a risk of bag bursting.

[0055] Sealing performance: Passed the burst pressure test (≥40 kPa), meeting the medical requirements.

[0056] Comparative Example 3 (Excessive high-temperature heat-sealing) Test results: The heat-sealing temperature of the upper sheet 10 and the lower sheet 20 is set at 230 °C, the pressure is 0.5 MPa, and the time is 4 s.

[0057] Performance test: Peeling condition: The peeling force is 10.0 N / 15 mm. The PP film tears during peeling, generating debris and unable to peel cleanly.

[0058] Sealing performance: The PP molecular chains at the sealed edge are prone to breakage, and the sterilization resistance decreases.

[0059] It can be seen that when the heat-sealing temperature is higher than 230 °C, it may cause breakage at the sealed edge and unable to seal.

[0060] Example 5 (High-density dot heat-pressing) Lower sheet composite process: The distance between the heat-pressing points is set at 15 mm (more dense), and the others are the same as in Example 1.

[0061] Performance test: Bonding strength: The peeling force between the SMMS non-woven fabric and the PP film reaches 8 N / 15 mm, and the composite structure is more stable.

[0062] Air permeability: The air permeability rate is 550 mL / (m²·s) (the heat-pressing points have a slight impact on the air permeability rate but still meet the standard).

[0063] Comparative Example 4 (Too large spacing between dot pressing and ironing) Lower sheet composite process: The spacing between pressing and ironing points is set to 40 mm (too sparse).

[0064] Test results: Interlayer separation: Separation between the non-woven fabric and the PP film easily occurs at the bag mouth, which is not convenient for encapsulating instruments and items.

[0065] According to the above embodiments, the preferred ranges of the key experimental parameters of the present invention and the conclusions are shown in Table 1 below: Table 1 Parameter range verification conclusion Parameter Preferred range Defects beyond the range Micropore diameter 100 - 500μm <100μm Insufficient air permeability; >500μm Mechanical weakening, affecting clean peeling Micropore density <![CDATA[6 - 25 per cm 2 > <6 pieces / cm² Insufficient air permeability; >25 pieces / cm² Increased processing cost Sealing and ironing temperature of upper and lower sheets 170-220℃ <170℃ Poor sealing; >220℃ Excessive peeling force, unable to peel cleanly, and the material structure is damaged Dot ironing spacing 15 - 35mm <15mm Blockage of air passage; >35mm Separation between layers, inconvenient for encapsulation Peeling force 2.0 - 7.0N / 15mm <2.0N / 15mm Risk of bag bursting, resulting in sterilization failure; >7.0N / 15mm Failure of clean peeling, causing secondary pollution

[0066] From the above embodiments and comparative examples, it can be seen that the parameter range of the present invention has been screened through a large number of experiments, and a non-linear balance has been achieved among air permeability, bacteriostatic property, peel strength, and environmental friendliness: Microporous design: The size of the laser micropores needs to be appropriate. If it is too small, the air permeability is insufficient, affecting the sterilization effect and the risk of bag explosion; if it is too large, the mechanical strength will be sacrificed, and the clean peel after sealing and ironing will be affected; Heat-sealing process window: The glass transition temperature (~0 °C) and melting point (~165 °C) of the PP material limit the lower and upper limits of the heat-sealing temperature, and precise control is required to achieve interfacial bonding rather than melting; Environmental compatibility: The recyclability of the all-PP system depends on the matching of the melt flow indices of each layer of materials. Introducing PE or PET will lead to difficult sorting, while the comparative example shows that only PP can achieve closed-loop recycling.

[0067] The above data prove that only within the parameter range defined by the present invention can the strict requirements of medical sterilization packaging be simultaneously met, and the synergistic effect among the parameters constitutes the creative contribution of the present invention compared with the prior art.

[0068] In summary, an environmentally friendly steam-resistant sterilizable medical packaging bag provided by the present invention has the following advantages: Material composite structure: Dot composite of SMMS non-woven fabric B1 and laser microporous PP film B2, taking into account bacteriostatic property and air permeability; Easy-peel design: The heat-sealing interface between the PP easy-peel film on the A side material and the B2 side PP film on the B side material realizes low-force clean peeling, solving the problem of peeling pollution in traditional packaging; Combination of environmental friendliness and functionality: The all-PP-based material system meets the dual requirements of sterilization resistance and recyclability.

[0069] The above are only the preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. Various changes can be made to the above embodiments of the present invention. All simple, equivalent changes and modifications made in accordance with the claims and the content of the specification of the present invention application fall within the scope of protection of the claims of the present invention. Those not described in detail in the present invention are all conventional technical contents.

Claims

1. An environmentally friendly medical packaging bag resistant to steam sterilization, wherein the medical sterilization packaging bag is formed by thermally pressing and sealing the upper sheet and the lower sheet through three sides, and the un-sealed part forms a bag opening, and the part opposite to the bag opening is the bag bottom, and it is characterized in that, The upper sheet is a PP easy-peel film. The lower sheet is formed by laminating SMMS non-woven fabric and a PP film through a dispersed dot heat-pressing process. The PP film faces the inner side of the bag, and the PP film has a number of micropores formed by laser processing and evenly distributed thereon.

2. The medical packaging bag according to claim 1, wherein, The SMMS non-woven fabric and the PP film are combined through a heat-pressing process to form a number of dispersed hot-pressing points. The diameter of the hot-pressing points is 1 - 2 mm, and the spacing between adjacent hot-pressing points is 15 - 35 mm.

3. The medical packaging bag according to claim 1, wherein The conditions of the dispersed dot heat-pressing process are: temperature 170 - 200 °C, pressure 0.3 - 0.5 MPa, and sealing and ironing time 1.5 - 3.5 s.

4. The medical packaging bag according to claim 1, characterized in that, The aperture of the micropores formed by laser processing on the PP film is 100 - 500 μm, and the pore spacing is 2 - 5 mm.

5. The medical packaging bag according to claim 1, wherein, The density of the micropores formed by laser processing on the PP film is 6 - 25 pieces / cm², meeting the gas exchange requirements during steam sterilization.

6. The medical packaging bag according to claim 1, wherein The conditions of the heat-pressing process for the upper sheet and the lower sheet are: temperature 170 - 220 °C, pressure 0.3 - 0.5 MPa, and sealing and ironing time 1.5 - 4 s.

7. The medical packaging bag according to claim 1, wherein, The peeling force between the PP film and the PP easy-peel film is controlled at 2.0 - 7.0 N / 15 mm, meeting the requirements of medical clean peeling.

8. The medical packaging bag according to claim 1, wherein, The thickness of the PP easy-peel film is 60 - 80 μm, and the surface tension is 30 - 35 mN / m.

9. The medical packaging bag according to claim 1, characterized in that, The grammage of the SMMS non-woven fabric is 30 - 40 g / m², and the thickness of the PP film is 25 - 35 μm.

10. The medical packaging bag according to claim 1, characterized in that, The bag bottom has a V-shaped structure.

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