Color-changing ink color master batch, sterilization indication type stripping heat-sealing film and preparation method and application of color-changing ink color master batch and sterilization indication type stripping heat-sealing film

Abstract

The invention discloses a color-changing ink color master batch, a sterilization indication type stripping heat-sealing film and a preparation method and application of the sterilization indication type stripping heat-sealing film, and relates to the field of organic materials. The master batch comprises heat-resistant particles, polyethylene, a lubricant and a compatilizer, and the preparation method of the heat-resistant particles comprises the following steps: dispersing an acid-base indicating pigment and a metal salt in a low-boiling-point solvent, evaporating a load composition, dissolving polyarylsulfone and the load composition in the solvent, and evaporating to obtain the heat-resistant particles, after being used for preparing the sterilization indication type stripping heat-sealing film, the heat-sealing film can be applied to the field of medical packaging bags. Polyarylsulfone forms a molecular layer structure on loaded composition particles, heat insulation and heat resistance effects are achieved, performance defects caused by high temperature and high pressure in the extrusion process on the pigment are avoided, when the prepared medical packaging bag is subjected to hydrogen peroxide ion sterilization treatment, hydrogen peroxide ions react with metal salt, the pH of the material is changed, the color of the pigment is changed, and the medical packaging bag has a good application prospect. And a disinfection worker can conveniently monitor the sterilization effect.

Description

Technical Field

[0001] The present application relates to the field of organic materials, and in particular to a color-changing ink masterbatch, a sterilization-indicating peelable heat-sealing film, and a preparation method and application thereof. Background Art

[0002] In the medical industry, medical packaging bags are used to store and transport various medical devices and medicines. These packaging bags need to have good sealing properties to ensure the safety and stability of the items inside. When hydrogen peroxide plasma is used for disinfection and sterilization of medical packaging bags, hydrogen peroxide is mainly plasmatized in a low-pressure (vacuum) environment, and the hydrogen peroxide plasma is used to provide a sterilization effect. This method does not require a high-temperature environment, so it can disinfect and sterilize a wider range of medical devices. The sterilization process takes a short time and has high practical value. There will be no drug residue after disinfection, so it is safe.

[0003] In order to monitor the sterilization effect of medical packaging bags, color-changing ink is usually printed or applied on the label of the packaging bag. The chemical indicators in the color-changing ink are used to indicate the sterilization process or whether the sterilization meets the qualified standards, so as to enhance quality control and sterilization efficiency.

[0004] At present, the sterilization detection color-changing ink of medical packaging bags needs additional printing process processing, which leads to an increase in the processing steps of medical packaging bags. The reason is that the pigment in the color-changing ink is not heat-resistant enough and cannot be co-extruded with the packaging bag film material at the same time. The high temperature and pressure in the co-extrusion process will cause performance defects to the color-changing ink and affect the color-changing effect.

[0005] Application Contents

[0006] The present application provides a color-changing ink masterbatch, a sterilization-indicating peelable heat-sealing film, and a preparation method and application thereof. Acid-base indicating pigments are co-extruded with polymers to prepare medical packaging bag materials. The pigments have excellent heat resistance and can undergo significant color changes after hydrogen peroxide ion sterilization to monitor the sterilization effect of medical packaging bags.

[0007] In order to solve the above technical problems, one of the purposes of the present application is to provide a color-changing ink masterbatch, comprising the following components by weight: 30-40 parts of heat-resistant particles, 50-65 parts of polyethylene, 1-3 parts of lubricant, and 1-3 parts of compatibilizer.

[0008] The preparation method of heat-resistant particles comprises the following steps:

[0009] (1) dispersing 8 wt% to 15 wt% of an acid-base indicator pigment in 68 wt% to 82 wt% of a low boiling point solvent, then adding 10 wt% to 17 wt% of a metal salt, and after ultrasonic dispersion, continuing stirring for a time greater than or equal to 4 h and less than or equal to 6 h, evaporating the low boiling point solvent to obtain a loaded composition,

[0010] (2) 3 wt% to 5 wt% of polyarylsulfone is added to 55 wt% to 67 wt% of a solvent to dissolve, and then 30 wt% to 40 wt% of a loading composition is added. After homogenizing and stirring for a time greater than or equal to 1 h and less than or equal to 3 h, the solvent is evaporated to obtain heat-resistant particles.

[0011] By adopting the above scheme, the present application soaks and adsorbs the acid-base indicating pigment and the metal salt, so that the metal salt can stay and be loaded on the surface of the acid-base indicating pigment to form a loaded composition, and uses polyarylsulfone to form a molecular layer structure in the loaded composition particles. Polyarylsulfone has high heat resistance, and the overflow of the solvent during the evaporation process can increase the porosity of the polyarylsulfone layer structure, play a heat insulating role, and effectively improve the heat resistance of the acid-base indicating pigment, avoiding the high temperature and high pressure in the extrusion process to cause performance defects to the acid-base indicating pigment and affect the color change effect. When the obtained color-changing ink masterbatch is sterilized by hydrogen peroxide ions, the hydrogen peroxide ions will react chemically with the metal salt, causing the pH of the material to change, thereby causing the acid-base indicating pigment to change color due to the change in pH, and the metal salt is mainly gathered and dispersed around the acid-base indicating pigment in the material, which helps to improve the color change degree of the acid-base indicating pigment and helps the naked eye to judge the color change.

[0012] As a preferred embodiment, the low boiling point solvent is at least one of acetone, methanol, ether, ethanol, tetrahydrofuran, hexane, trichloroethane, dichloroethane, pentane and ethyl acetate.

[0013] As a preferred embodiment, the solvent is at least one of dimethylformamide, dimethyl sulfoxide and N-methylpyrrolidone.

[0014] As a preferred embodiment, the metal salt is at least one of magnesium chloride, potassium iodide and magnesium iodide.

[0015] As a preferred embodiment, the mass ratio of the acidic indicator pigment to the metal salt is (2-4):3.

[0016] As a preferred embodiment, the mass ratio of the acidic indicator pigment to the metal salt is in the range of 2:3, 3:3, 4:3 or any two of them.

[0017] By adopting the above scheme, the present application controls the ratio of the acidic indicator pigment and the metal salt, which can prevent the acidic substances generated by the excessive reaction of the metal salt with hydrogen peroxide from affecting the performance of the material itself, and at the same time can provide a pH environment that satisfies the color change of the acid-base indicator pigment, thereby improving the color change effect.

[0018] As a preferred embodiment, the mass ratio of polyarylsulfone to the supported composition is (1-3):20.

[0019] As a preferred embodiment, the mass ratio of polyarylsulfone to the supported composition is in the range of one or any two of 1:20, 2:20, and 3:20.

[0020] By adopting the above scheme, when the color-changing ink masterbatch of the present application is sterilized by hydrogen peroxide ions, a chemical reaction between metal salt and hydrogen peroxide is used to cause a change in the pH value of the material, thereby causing the acid-base indicator pigment to change color due to the influence of pH. Controlling a specific content of polyarylsulfone forms a molecular structure layer on the surface of the acid-base indicator pigment particles, which is beneficial to improving the color-changing effect of the material during the hydrogen peroxide ion sterilization process. The reason is that excessive addition of polyarylsulfone during the preparation of heat-resistant particles will lead to a lighter degree of color change of the acid-base indicator pigment, and the color difference is small and difficult to distinguish with the naked eye. Excessive addition of polyarylsulfone will lead to insufficient heat resistance of the heat-resistant particles, and the performance of the acid-base indicator pigment will be defective, resulting in some acid-base indicator pigments being unable to accurately change color with pH changes.

[0021] As a preferred embodiment, the acid-base indicating pigment is at least one of methyl red, bromocresol green, Congo red, methyl orange, bromophenol blue and methyl yellow.

[0022] As a preferred embodiment, the lubricant is at least one of stearic acid, zinc stearate and polyethylene wax.

[0023] As a preferred embodiment, the compatibilizer is at least one of maleic anhydride grafted polypropylene, maleic anhydride grafted polyethylene, and maleic anhydride grafted ABS.

[0024] As a preferred embodiment, in step (1), the ultrasonic dispersion time is greater than or equal to 5 min and less than or equal to 15 min.

[0025] As a preferred embodiment, in step (1), the evaporation temperature is greater than or equal to 60°C and less than or equal to 80°C.

[0026] As a preferred embodiment, in step (2), the evaporation temperature is greater than or equal to 60°C and less than or equal to 80°C.

[0027] As a preferred embodiment, in step (2), 3wt%-5wt% polyarylsulfone is added to 55wt%-67wt% solvent and dissolved in a water bath at a water bath temperature greater than or equal to 40°C and less than or equal to 50°C, followed by adding 30wt%-40wt% of the loading composition.

[0028] As a preferred embodiment, in step (2), the homogenizing stirring rate is greater than or equal to 300 rpm and less than or equal to 400 rpm.

[0029] In order to solve the above-mentioned technical problems, the second purpose of the present application provides a method for preparing a color-changing ink masterbatch, comprising the following steps: grinding and dispersing the heat-resistant particles and polyethylene evenly, then blending, plasticizing, extruding and granulating the ground material with a lubricant and a compatibilizer, and the extrusion temperature is greater than or equal to 160°C and less than or equal to 200°C to obtain a color-changing ink masterbatch.

[0030] In order to solve the above technical problems, the third purpose of the present application provides a sterilization-indicating peelable heat-sealing film, comprising the following components in parts by weight: 50-60 parts of polyethylene, 10-15 parts of color-changing ink masterbatch, 1-3 parts of antioxidant, and 20-30 parts of polybutene.

[0031] As a preferred embodiment, the polyethylene is low-density polyethylene and / or linear low-density polyethylene.

[0032] As a preferred embodiment, the antioxidant is at least one of antioxidant 1010, antioxidant 168, and antioxidant 1076.

[0033] In order to solve the above-mentioned technical problems, the fourth purpose of the present application provides a method for preparing a sterilization-indicating peelable heat-sealing film, comprising the following steps: adding color-changing ink masterbatch, polyethylene, polybutene, and antioxidant into an extruder for mixing, melting and forming a tube blank through the extruder, stretching the tube blank and blowing it into a bubble film, the blow molding temperature is greater than or equal to 130°C and less than or equal to 140°C, and cooling and shaping to obtain a film.

[0034] In order to solve the above technical problems, the fifth purpose of the present application provides a sterilization-indicating peel-off heat-sealing film for use in the field of preparing medical packaging bags.

[0035] As a preferred embodiment, the medical packaging bag includes a first material and a nonwoven material, the first material and the nonwoven material form opposite sides of the medical packaging bag, the first material is located between the first material and the nonwoven material and a seal is arranged, the seal includes a barrier layer, an adhesive layer and a peeling heat sealing layer arranged in sequence, the adhesive layer and the peeling heat sealing layer include a sealed state and an open state.

[0036] The seal seals the connection between the first material and the nonwoven material, so that the interior of the medical packaging bag forms a closed cavity, which can contain objects and prevent bacteria or impurities from entering the interior of the packaging bag. When the packaging bag is in a closed configuration, the packaging bag and the objects placed inside the packaging bag can be sterilized using hydrogen peroxide ions, and the sterilization effect of the medical packaging bag is detected by the color change of the peeled heat seal layer. The color change of the peeled heat seal layer not exposed to the air and the exposed to the air is different during the hydrogen peroxide sterilization treatment, and the integrity of the seal can be visually checked to ensure that there is no breakage or rupture of the peeled heat seal layer that causes damage to the packaging bag.

[0037] As a preferred solution, the first material can be a film made of a polymer material, and the polymer material includes but is not limited to at least one of polyethylene, polyester, nylon, polypropylene, polybutylene, and other polymers used as structural materials.

[0038] As a preferred solution, the first material and the sealant can be co-extruded or extruded separately, including but not limited to lamination, coating or co-extrusion.

[0039] As a preferred solution, the barrier layer, the adhesive layer and the peeling heat-sealing layer can be co-extruded to form the first material, and the nonwoven material can be fixed by heat sealing, ultrasonic sealing or impulse sealing and the peeling sterilization heat-sealing layer.

[0040] As a preferred solution, the first material can be transparent or tinted. The transparent first film material can be used to observe the color of the sterilization peeling film, and the tinted first film material can cooperate with the color of the sterilization peeling indicator layer to provide a third color, which is convenient for intuitively displaying color changes.

[0041] As a preferred embodiment, the nonwoven material can be nonwoven high-density polyethylene, which is made by flash evaporation. Preferably, the nonwoven material can be commercially available from Xiamen Dangsheng New Materials Co., Ltd. A product that allows sealed medical packaging bags and objects in the medical packaging bags to be sterilized using ethylene oxide gas, and also allows the ethylene oxide gas to be exhausted.

[0042] As a preferred solution, the barrier layer is sealed to the first material, and the barrier layer can be made of at least one of polyethylene, polyester, nylon, polypropylene, and other polymer materials that serve as packaging structural components. Preferably, the barrier layer can be transparent, thereby allowing objects placed in the medical packaging bag to be visually identified while remaining sealed in the medical packaging bag.

[0043] As a preferred embodiment, a tie layer is sealed to the barrier layer, and the tie layer may be low density polyethylene, linear low density polyethylene or other polymers.

[0044] As a preferred solution, the adhesive layer can be a pressure-sensitive adhesive, which allows the peeling heat seal layer to be separated from the adhesive layer and re-sealed, and is preferably transparent or colorless. The peeling heat seal layer of the present application contains polyethylene and an incompatible polymer polybutylene, and the incompatible polymers weaken the bonding between the polymer chains, thereby making the peeling heat seal layer easier to separate from the adhesive layer.

[0045] As a preferred embodiment, the peeling heat seal layer and the adhesive layer may have a peeling strength of greater than or equal to 1N / 15mm and less than or equal to 10N / 15mm, preferably, greater than or equal to 3N / 15mm and less than or equal to 6N / 15mm. Such peeling strength allows the package to be opened or arranged in an open configuration without significantly loosening or compressing the fibers of the nonwoven material or causing the nonwoven material to tear. When the packaging bag is in an open configuration, the peeling heat seal layer is substantially separated from the adhesive layer, the adhesive layer remains coupled to the first film material, 90% or more of the peeling heat seal layer is transferred to the nonwoven material, and a small amount such as 10% or less remains coupled to the adhesive layer.

[0046] Compared with the prior art, this application has the following beneficial effects:

[0047] The present application utilizes polyarylsulfone to form a molecular layer structure in the loaded composition particles. Polyarylsulfone has high heat resistance, and the overflow of the solvent during the evaporation process can increase the porosity of the polyarylsulfone layer structure, play a heat-insulating role, and effectively improve the heat resistance of the acid-base indicator pigment in the loaded composition particles, avoiding high temperature and high pressure in the extrusion process causing pigment performance defects. When the color-changing ink masterbatch is sterilized with hydrogen peroxide ions, the hydrogen peroxide ions will chemically react with the metal salt, causing the pH of the material to change, thereby causing the pigment to change color. The metal salt is mainly aggregated and dispersed in the material and loaded around the surface of the acid-base indicator pigment, which helps to increase the color change degree of the acid-base indicator pigment and helps the naked eye to judge the color change. DETAILED DESCRIPTION

[0048] The following will be combined with the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0049] The following are the sources and types of raw materials used in the examples and comparative examples of this application:

[0050] Polyarylsulfone, brand is Solvay, USA, model is R-5500.

[0051] Low-density polyethylene, brand is McLean, model is L790446, melt index is 70g / 10min, particle size is 600 mesh.

[0052] Linear low-density polyethylene, brand is McLean, model is L909897, and melt flow rate is 2g / 10min.

[0053] Polybutene, brand is McLean, model is P909455.

[0054] Antioxidant, brand is BASF of Germany, model is 1010.

[0055] Example 1

[0056] A sterilization-indicating peelable heat-sealing film, the preparation method of which comprises the following steps:

[0057] (1) 10 wt % bromocresol green was dispersed in 75 wt % acetone, and then 15 wt % magnesium chloride was added. After ultrasonic dispersion for 10 min, stirring was continued for 5 h, and acetone was evaporated at 70° C. to obtain a loaded composition.

[0058] (2) 4 wt% polyarylsulfone is added to a container containing 56 wt% N-methylpyrrolidone solvent, heated in a 40°C water bath and stirred to dissolve, and then 40 wt% of the loading composition is added, and homogenized and stirred for 2 hours at a homogenization stirring rate of 300 rpm. Then, the solvent is evaporated at 80°C, so that the polyarylsulfone is coated on the surface of the dye particles to form a molecular protective layer, and the solvent vaporization overflow during the evaporation process can increase the porosity of the protective layer structure, provide heat insulation, and obtain heat-resistant particles.

[0059] (3) 40 wt% of heat-resistant particles and 55 wt% of low-density polyethylene are fed into a grinding device and ground by a three-roll grinding process to uniformly disperse the heat-resistant particles in the polyethylene. Subsequently, the ground material and 2 wt% of zinc stearate and 3 wt% of maleic anhydride grafted polyethylene are added to a stirring device for blending. After plasticizing in a plasticizer, the material is extruded and granulated in an extruder at a temperature of 160-170°C. The material is cooled and solidified to obtain a color-changing ink masterbatch.

[0060] (4) 10 wt% color-changing ink masterbatch, 59 wt% low-density polyethylene, 28 wt% polybutene, and 3 wt% antioxidant 1010 are added to the extruder. The materials are fully mixed in the screw barrel, melted and formed into a tube billet through the extruder, and the tube billet is stretched and compressed air is blown out from the center of the extruder die head to inflate the tube billet into a bubble film. The film bubble is adjusted to the desired size using an internal cooling and stabilizing bubble device, and the film is cooled and shaped to obtain a film. The blow molding temperature is 130-140°C.

[0061] Example 2

[0062] A sterilization-indicating peelable heat-sealing film, the preparation method of which comprises the following steps:

[0063] (1) 12 wt % methyl red was dispersed in 88 wt % tetrahydrofuran, and then 10 wt % magnesium chloride was added. After ultrasonic dispersion for 10 min, stirring was continued for 5 h, and acetone was evaporated at 70° C. to obtain a loaded composition.

[0064] (2) 3 wt% polyarylsulfone is added to a container containing 67 wt% N-methylpyrrolidone solvent, heated in a 40°C water bath and stirred to dissolve, and then 30 wt% of the loading composition is added, and homogenized and stirred for 2 hours at a homogenization stirring rate of 300 rpm. Then, the solvent is evaporated at 80°C, so that the polyarylsulfone is coated on the surface of the dye particles to form a molecular protective layer, and the solvent vaporization overflow during the evaporation process can increase the porosity of the protective layer structure, provide heat insulation, and obtain heat-resistant particles.

[0065] (3) 30 wt% of heat-resistant particles and 65 wt% of low-density polyethylene are fed into a grinding device and ground by a three-roll grinding process to uniformly disperse the heat-resistant particles in the polyethylene. Subsequently, the ground material and 1 wt% of polyethylene wax and 4 wt% of maleic anhydride grafted polypropylene are added to a stirring device for blending. After plasticizing in a plasticizer, the material is extruded and granulated in an extruder at a temperature of 160-170°C. The material is cooled and solidified to obtain a color-changing ink masterbatch.

[0066] (4) 15 wt% color-changing ink masterbatch, 57 wt% low-density polyethylene, 26 wt% polybutene, and 2 wt% antioxidant 1010 are added to the extruder, and the materials are fully mixed in the screw barrel, melted and formed into a tube billet through the extruder, and the tube billet is stretched and compressed air is rushed out from the center of the extruder die head to blow the tube billet into a bubble film, and the film bubble is adjusted to the desired size by an internal cooling and stabilizing bubble device, and the film is cooled and shaped to obtain a film. The blow molding temperature is 130-140°C.

[0067] Example 3

[0068] A sterilization-indicating peelable heat-sealing film, the preparation method of which comprises the following steps:

[0069] (1) 15 wt% Congo red was dispersed in 73 wt% methanol, and then 12 wt% magnesium chloride was added. After ultrasonic dispersion for 10 min, stirring was continued for 5 h, and acetone was evaporated at 70° C. to obtain a loaded composition.

[0070] (2) 3 wt% polyarylsulfone is added to a container containing 62 wt% N-methylpyrrolidone solvent, heated in a water bath at 40°C and stirred to dissolve, and then 35 wt% of the loading composition is added, and homogenized and stirred for 2 hours at a homogenization stirring rate of 300 rpm. The solvent is then evaporated at 80°C to allow the polyarylsulfone to coat the surface of the dye particles to form a molecular protective layer, and the solvent vaporization overflow during the evaporation process can increase the porosity of the protective layer structure, provide heat insulation, and obtain heat-resistant particles.

[0071] (3) 35wt% of heat-resistant particles and 61wt% of low-density polyethylene are fed into a grinding device and ground by a three-roll grinding process to uniformly disperse the heat-resistant particles in the polyethylene. Subsequently, the ground material and 3wt% of stearic acid and 1wt% of maleic anhydride grafted ABS are added to a stirring device for blending. After plasticizing in a plasticizer, the material is extruded and granulated in an extruder at a temperature of 160-170°C. The material is cooled and solidified to obtain a color-changing ink masterbatch.

[0072] (4) 12 wt% color-changing ink masterbatch, 56 wt% low-density polyethylene, 30 wt% polybutene, and 2 wt% antioxidant 1010 are added to the extruder, and the materials are fully mixed in the screw barrel, melted and formed into a tube billet through the extruder, and the tube billet is stretched and compressed air is rushed out from the center of the extruder die head to blow the tube billet into a bubble film, and the film bubble is adjusted to the desired size by an internal cooling and stabilizing bubble device, and the film is cooled and shaped to obtain a film, and the blow molding temperature is 130-140°C.

[0073] Example 4

[0074] A sterilization-indicating peelable heat-sealing film, wherein the steps of the preparation method thereof and the reagents, equipment and process parameters used in the steps are the same as those in Example 1, except that, in step (2), 6 wt% polyarylsulfone is added to a container containing 54 wt% N-methylpyrrolidone solvent, heated in a 40°C water bath and stirred to dissolve, and then 40 wt% of a loading composition is added, and homogenized and stirred for 2 hours at a homogenized stirring rate of 300 rpm, and then the solvent is evaporated at a temperature of 80°C, so that the polyarylsulfone is coated on the surface of dye particles to form a molecular protective layer, and the solvent vaporization overflow during the evaporation process can increase the porosity of the protective layer structure, provide a heat-insulating effect, and obtain heat-resistant particles.

[0075] Example 5

[0076] A sterilization-indicating peelable heat-sealing film, wherein each step of the preparation method thereof and the reagents, equipment and process parameters used in each step are the same as those in Example 1, except that, in step (2), 3 wt% polyarylsulfone is added to a container containing 57 wt% N-methylpyrrolidone solvent, heated in a 40°C water bath and stirred to dissolve, and then 40 wt% of a loading composition is added, and homogenized and stirred for 2 hours at a homogenized stirring rate of 300 rpm, and then the solvent is evaporated at a temperature of 80°C, so that the polyarylsulfone is coated on the surface of dye particles to form a molecular protective layer, and the solvent vaporization overflow during the evaporation process can increase the porosity of the protective layer structure, provide a heat-insulating effect, and obtain heat-resistant particles.

[0077] Example 6

[0078] A sterilization-indicating peelable heat-sealing film, wherein the steps of the preparation method and the reagents, equipment and process parameters used in the steps are the same as those in Example 1, except that, in step (1), 15 wt% of bromocresol green is dispersed in 82 wt% of acetone, and then 10 wt% of magnesium chloride is added. After ultrasonic dispersion for 10 min, stirring is continued for 5 h, and acetone is evaporated at a temperature of 70° C. to obtain a loaded composition.

[0079] Example 7

[0080] A sterilization-indicating peelable heat-sealing film, wherein the steps of the preparation method and the reagents, equipment and process parameters used in the steps are the same as those in Example 1, except that, in step (1), 8 wt% of bromocresol green is dispersed in 75 wt% of acetone, and then 17 wt% of magnesium chloride is added. After ultrasonic dispersion for 10 min, stirring is continued for 5 h, and acetone is evaporated at a temperature of 70° C. to obtain a loaded composition.

[0081] Example 8

[0082] A sterilization-indicating peelable heat-sealing film, wherein the steps of the preparation method and the reagents, equipment and process parameters used in the steps are the same as those in Example 1, except that, in step (4), 10 wt% of color-changing ink masterbatch, 39 wt% of low-density polyethylene, 20 wt% of linear low-density polyethylene, 28 wt% of polybutene and 3 wt% of antioxidant 1010 are added to an extruder, the materials are fully mixed in a screw barrel, melted and formed into a tube billet through the extruder, the tube billet is stretched, and compressed air is ejected from the center of the extruder die head to inflate the tube billet into a bubble film, an internal cooling and stabilizing bubble device is used to adjust the film bubble to a desired size, and the film is cooled and shaped to obtain a film, and the blow molding temperature is 130-140°C.

[0083] Comparative Example 1

[0084] A sterilization-indicating peelable heat-sealing film, the preparation method of which comprises the following steps:

[0085] (1) 4 wt% polyarylsulfone is added to a container containing 56 wt% N-methylpyrrolidone solvent, heated in a 40°C water bath and stirred to dissolve, then 40 wt% bromocresol green is added, and homogenized and stirred for 2 hours at a homogenization stirring rate of 300 rpm, and then the solvent is evaporated at 80°C, so that the polyarylsulfone is coated on the surface of the dye particles to form a molecular protective layer, and the solvent vaporization overflow during the evaporation process can increase the porosity of the protective layer structure, provide heat insulation, and obtain heat-resistant particles.

[0086] (2) 16 wt% of heat-resistant particles, 24 wt% of magnesium chloride and 55 wt% of low-density polyethylene are fed into a grinding device and ground by a three-roll grinding process to uniformly disperse the heat-resistant particles in the polyethylene. Subsequently, the ground material and 2 wt% of zinc stearate and 3 wt% of maleic anhydride grafted polyethylene are added to a stirring device for blending. After plasticizing in a plasticizer, the material is extruded and granulated in an extruder at a temperature of 160-170°C. The material is cooled and solidified to obtain a color-changing ink masterbatch.

[0087] (3) 10 wt% color-changing ink masterbatch, 59 wt% low-density polyethylene, 28 wt% polybutene, and 3 wt% antioxidant 1010 are added to the extruder, the materials are fully mixed in the screw barrel, melted and formed into a tube billet through the extruder, and the tube billet is stretched and compressed air is blown out from the center of the extruder die head to inflate the tube billet into a bubble film. The film bubble is adjusted to the desired size using an internal cooling and stabilizing bubble device, and the film is cooled and shaped to obtain a film. The blow molding temperature is 130-140°C.

[0088] Comparative Example 2

[0089] A sterilization-indicating peelable heat-sealing film, the preparation method of which comprises the following steps:

[0090] (1) 10 wt % bromocresol green was dispersed in 75 wt % acetone, and then 15 wt % magnesium chloride was added. After ultrasonic dispersion for 10 min, stirring was continued for 5 h, and acetone was evaporated at 70° C. to obtain a loaded composition.

[0091] (2) 40 wt% of the loaded composition and 55 wt% of low-density polyethylene are fed into a grinding device and ground by a three-roll grinding process to uniformly disperse the heat-resistant particles in the polyethylene. Subsequently, the ground material and 2 wt% of zinc stearate and 3 wt% of maleic anhydride grafted polyethylene are added to a stirring device for blending. After plasticizing in a plasticizer, the material is extruded and granulated in an extruder at a temperature of 160-170°C. The material is cooled and solidified to obtain a color-changing ink masterbatch.

[0092] (3) 10 wt% color-changing ink masterbatch, 59 wt% low-density polyethylene, 28 wt% polybutene, and 3 wt% antioxidant 1010 are added to the extruder, the materials are fully mixed in the screw barrel, melted and formed into a tube billet through the extruder, and the tube billet is stretched and compressed air is blown out from the center of the extruder die head to inflate the tube billet into a bubble film. The film bubble is adjusted to the desired size using an internal cooling and stabilizing bubble device, and the film is cooled and shaped to obtain a film. The blow molding temperature is 130-140°C.

[0093] Comparative Example 3

[0094] A sterilization-indicating peelable heat-sealing film, the preparation method of which comprises the following steps:

[0095] (1) 16 wt% of bromocresol green, 24 wt% of magnesium chloride and 55 wt% of low-density polyethylene are fed into a grinding device and ground by a three-roll grinding process to uniformly disperse the heat-resistant particles in the polyethylene. Subsequently, the ground material and 2 wt% of zinc stearate and 3 wt% of maleic anhydride grafted polyethylene are added to a stirring device for blending. After plasticizing in a plasticizer, the material is extruded and granulated in an extruder at a temperature of 160-170° C., and the material is cooled and solidified to obtain a color-changing ink masterbatch.

[0096] (2) 10 wt% color-changing ink masterbatch, 59 wt% low-density polyethylene, 28 wt% polybutene, and 3 wt% antioxidant 1010 are added to an extruder. The materials are fully mixed in the screw barrel, melted and formed into a tube billet through the extruder, and the tube billet is stretched and compressed air is blown out from the center of the extruder die head to inflate the tube billet into a bubble film. The film bubble is adjusted to the desired size using an internal cooling and stabilizing bubble device, and the film is cooled and shaped to obtain a film. The blow molding temperature is 130-140°C.

[0097] Comparative Example 4

[0098] A sterilization-indicating peelable heat-sealing film, wherein the steps of the preparation method thereof and the reagents, equipment and process parameters used in the steps are the same as those in Example 1, except that, in step (2), 8 wt% of polyarylsulfone is added to a container containing 52 wt% of N-methylpyrrolidone solvent, heated in a 40°C water bath and stirred to dissolve, and then 40 wt% of a loading composition is added, and homogenized and stirred for 2 hours at a homogenized stirring rate of 300 rpm, and then the solvent is evaporated at a temperature of 80°C, so that the polyarylsulfone is coated on the surface of dye particles to form a molecular protective layer, and the solvent vaporization overflow during the evaporation process can increase the porosity of the protective layer structure, provide a heat-insulating effect, and obtain heat-resistant particles.

[0099] Comparative Example 5

[0100] A sterilization-indicating peelable heat-sealing film, wherein the steps of the preparation method thereof and the reagents, equipment and process parameters used in the steps are the same as those in Example 1, except that, in step (2), 1 wt% polyarylsulfone is added to a container containing 59 wt% N-methylpyrrolidone solvent, heated in a 40°C water bath and stirred to dissolve, and then 40 wt% of a loading composition is added, and homogenized and stirred for 2 hours at a homogenized stirring rate of 300 rpm, and then the solvent is evaporated at a temperature of 80°C, so that the polyarylsulfone is coated on the surface of dye particles to form a molecular protective layer, and the solvent vaporization overflow during the evaporation process can increase the porosity of the protective layer structure, provide a heat-insulating effect, and obtain heat-resistant particles.

[0101] Comparative Example 6

[0102] A sterilization-indicating peelable heat-sealing film, wherein the steps of the preparation method and the reagents, equipment and process parameters used in the steps are the same as those in Example 1, except that, in step (1), 18 wt% of bromocresol green is dispersed in 82 wt% of acetone, and then 7 wt% of magnesium chloride is added. After ultrasonic dispersion for 10 min, stirring is continued for 5 h, and acetone is evaporated at a temperature of 70° C. to obtain a loaded composition.

[0103] Comparative Example 7

[0104] A sterilization-indicating peelable heat-sealing film, wherein the steps of the preparation method and the reagents, equipment and process parameters used in the steps are the same as those in Example 1, except that, in step (1), 6 wt% of bromocresol green is dispersed in 75 wt% of acetone, and then 19 wt% of magnesium chloride is added. After ultrasonic dispersion for 10 min, stirring is continued for 5 h, and acetone is evaporated at a temperature of 70° C. to obtain a loaded composition.

[0105] Performance testing

[0106] 1. The peelable heat-sealing films prepared in the examples and comparative examples were placed in a hydrogen peroxide low-temperature plasma sterilizer for sterilization, using 55% high-concentration hydrogen peroxide, a working temperature of 50°C, and a sterilization cycle of 40 minutes. The color change of the peelable heat-sealing films before and after sterilization was observed with the naked eye, and the results were recorded as shown in Table 1 below.

[0107] 2. The peelable heat-sealed films prepared in the embodiments and comparative examples were placed in a hydrogen peroxide low-temperature plasma sterilizer for sterilization, using 55% high-concentration hydrogen peroxide, the working temperature was 50°C, the sterilization cycle was 40 minutes, and the color difference test was performed on the peelable heat-sealed films before and after sterilization. The initial Lab* value before sterilization and the Lab* value after sterilization were measured using a spectrophotometer. The spectrophotometer was a Konica Minilta CM-2600d, with a measurement range of 360-740nm, a measurement interval of 10nm, a light source of D65, and a color difference calculation method using the CIE Lab color space to calculate the total color difference ΔE before and after sterilization: ΔE=√[(ΔL)2+(Δa*)2+(Δb*)2], requiring ΔE to be greater than or equal to 5. The calculation results are shown in Table 1 below.

[0108] Table 1-Color difference results of films prepared in the present application examples and comparative examples before and after sterilization test

[0109]

[0110]

[0111] As shown in Table 1, by comparing the schemes of Example 1 and Comparative Example 1, it can be seen that when the peeling heat-sealing film material of the present application is sterilized by hydrogen peroxide ions, the metal salt reacts with hydrogen peroxide to cause the pH of the material to change, thereby causing the acid-base indicator pigment to change color due to the influence of pH. In Example 1, the acid-base indicator pigment and the metal salt are pre-immersed and adsorbed, so that the metal salt can stay and be loaded on the surface of the acid-base indicator pigment to form a loaded composition. In the peeling heat-sealing film material finally prepared, the metal salt is mainly gathered and dispersed around the acid-base indicator pigment in the material, which helps to improve the color change degree of the acid-base indicator pigment. The color difference after color change is large, which helps the naked eye to judge the color change. However, the metal salt in Comparative Example 1 is not pre-loaded on the surface of the pigment particles. The pigment surface is affected by the polyarylsulfone molecules and enriched with less metal salt, resulting in a relatively high pH environment around the pigment, insufficient color change of the pigment, small color difference, and relatively inaccurate judgment by the naked eye.

[0112] As shown in Table 1, by comparing the schemes of Example 1 and Comparative Examples 2-3, it can be seen that the present application uses polyarylsulfone to form a molecular layer structure in the loaded composition particles. Polyarylsulfone itself has high heat resistance, and the boiling point of N-methylpyrrolidone solvent is relatively low. Overflow during evaporation can increase the porosity of the polyarylsulfone layer structure, play a heat-insulating role, and effectively improve the heat resistance of the acid-base indicator pigment, avoiding the high temperature and high pressure in the extrusion process. The pigment causes performance defects to the pigment and affects the color change effect during hydrogen peroxide ion sterilization. However, the pigment in the peeling heat-sealing film material in Comparative Examples 2-3 does not form a polyarylsulfone molecular layer structure on the surface, and the acid-base indicating pigment has poor heat resistance and cannot adapt to the high temperature and high pressure environment of the extrusion process. The color change effect of the peeling heat-sealing film material finally prepared after hydrogen peroxide ion sterilization is poor, and some pigments cannot change color with pH changes. The color difference after sterilization is small, which affects the sterilization effect judged by the naked eye.

[0113] As shown in Table 1, by comparing the schemes of Examples 1, 4-5 and Comparative Examples 4-5, it can be seen that Examples 1 and 4-5 of the present application control the specific content of polyarylsulfone to form a molecular structure layer on the surface of the acid-base indicator pigment particles, which is beneficial to improving the color change effect of the material during the hydrogen peroxide ion sterilization process, while excessive addition of polyarylsulfone during the preparation of the heat-resistant particles in Comparative Example 4 will result in a lighter degree of color change of the acid-base indicator pigment, a smaller color difference, and a small color difference after sterilization. Excessive addition of polyarylsulfone during the preparation of the heat-resistant particles in Comparative Example 5 will result in insufficient heat resistance of the heat-resistant particles, defects in the performance of the acid-base indicator pigment, and the inability of some acid-base indicator pigments to accurately change color with changes in pH, and a smaller color difference, which affects the naked eye's judgment of the sterilization effect.

[0114] As shown in Table 1, by comparing the solutions of Examples 1, 6-7 and Comparative Examples 6-7, it can be seen that Examples 1 and 6-7 of the present application control the ratio of the acidic indicator pigment and the metal salt within a specific range. Compared with Comparative Examples 6-7, a pH environment that satisfies the color change of the acid-base indicator pigment can be provided, and the acidic substances generated by the reaction of excessive metal salt with hydrogen peroxide affecting the performance of the material itself, or too little metal salt can not provide a pH environment for the pigment to change color, thereby improving the color change effect.

[0115] The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present application in detail. It should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the scope of protection of the present application. It is particularly pointed out that for those skilled in the art, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A color-changing ink masterbatch, characterized in that: The invention comprises the following components by weight: 30-40 parts of heat-resistant particles, 50-65 parts of polyethylene, 1-3 parts of lubricant, and 1-3 parts of compatibilizer. The preparation method of the heat-resistant particles comprises the following steps: (1) dispersing 8 wt% to 15 wt% of an acid-base indicator pigment in 68 wt% to 82 wt% of a low boiling point solvent, then adding 10 wt% to 17 wt% of a metal salt, and after ultrasonic dispersion, continuing stirring for a time greater than or equal to 4 h and less than or equal to 6 h, evaporating the low boiling point solvent to obtain a loaded composition, (2) 3 wt% to 5 wt% of polyarylsulfone is added to 55 wt% to 67 wt% of a solvent to dissolve, and then 30 wt% to 40 wt% of the loading composition is added, and the homogenization stirring time is greater than or equal to 1 hour and less than or equal to 3 hours, and the solvent is evaporated to obtain the heat-resistant particles.

2. A color-changing ink masterbatch as claimed in claim 1, characterized in that: The low boiling point solvent is at least one of acetone, methanol, ether, ethanol, tetrahydrofuran, hexane, trichloroethane, dichloroethane, pentane, and ethyl acetate; and the solvent is at least one of dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone.

3. A color-changing ink masterbatch as claimed in claim 1, characterized in that: The metal salt is at least one of magnesium chloride, potassium iodide and magnesium iodide.

4. A color-changing ink masterbatch as claimed in claim 1, characterized in that: The mass ratio of the acidic indicator pigment to the metal salt is (2-4):

3.

5. The color-changing ink masterbatch according to claim 1, characterized in that: The acid-base indicating pigment is at least one of methyl red, bromocresol green, Congo red, methyl orange, bromophenol blue and methyl yellow.

6. A color-changing ink masterbatch as claimed in claim 1, characterized in that: The lubricant is at least one of stearic acid, zinc stearate and polyethylene wax, and the compatibilizer is at least one of maleic anhydride grafted polypropylene, maleic anhydride grafted polyethylene and maleic anhydride grafted ABS.

7. A method for preparing a color-changing ink masterbatch according to any one of claims 1 to 6, characterized in that: The following steps are involved: The heat-resistant particles and the polyethylene are ground and dispersed uniformly, and then the ground material is blended with the lubricant and the compatibilizer, plasticized, extruded, and granulated. The extrusion temperature is greater than or equal to 160° C. and less than or equal to 200° C. to obtain the color-changing ink masterbatch.

8. A sterilization indicating peelable heat-sealing film, characterized in that: The color-changing ink masterbatch as claimed in any one of claims 1 to 6 comprises the following components in parts by weight: 50 to 60 parts of polyethylene, 10 to 15 parts of the color-changing ink masterbatch, 1 to 3 parts of an antioxidant, and 20 to 30 parts of polybutene.

9. A method for preparing a sterilization indicating peelable heat-sealing film according to claim 8, characterized in that: The following steps are involved: The color-changing ink masterbatch, the polyethylene, the polybutene and the antioxidant are added into an extruder for mixing, melted and formed into a tube billet through the extruder, and the tube billet is stretched and blown into a bubble film at a blow molding temperature of greater than or equal to 130° C. and less than or equal to 140° C., and cooled and shaped to obtain a film.

10. Use of the sterilization indicating peelable heat-sealing film according to claim 8 in the field of preparing medical packaging bags.

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