CN114801401A

CN114801401A - Clean easy-to-open cover film for liquid packaging

Info

Publication number: CN114801401A
Application number: CN202210287442.3A
Authority: CN
Inventors: 黄湘晖; 李全布; 曹凯; 涂成波; 王清
Original assignee: Bemis Flexible Packaging Suzhou Co Ltd
Current assignee: Bemis Flexible Packaging Suzhou Co Ltd
Priority date: 2022-03-23
Filing date: 2022-03-23
Publication date: 2022-07-29

Abstract

The invention discloses a clean easy-to-tear cover film for liquid packaging, which comprises an outer layer, an adhesive layer, an aluminum foil layer and an inner layer from outside to inside; the outer layer is made of paper; the adhesive layer comprises 5-10 parts of linear polysiloxane, 1-2 parts of cross-linking agent, 12-40 parts of epoxy resin, 4-17 parts of polyurethane and 0.5-1.5 parts of antioxidant; the inner layer comprises 15-60 parts of polyethylene glycol terephthalate-1, 4-cyclohexane dimethanol ester, 12-35 parts of polyvinyl chloride, 0.5-2 parts of plasticizer, 2-8 parts of polyacrylate, 0.3-0.5 part of curing agent, 0.1-0.4 part of smoothing agent and 2-6 parts of silicate. The invention can realize excellent chemical resistance, high peel strength, high tensile strength and excellent comprehensive properties in all aspects.

Description

Clean easy-to-open cover film for liquid packaging

Technical Field

The invention relates to the field of composite sheets, in particular to a clean easy-to-open cover film for liquid packaging.

Background

With the rapid development of biological medicine, the requirement of IVD rapid diagnosis is continuously perfected, and a porous plate consumable needs to be adopted for preparation of a detection sample in the sampling process. The perforated plate usually adopts a prefabricated forming bottom box made of PVC, APET, PP and other materials, the sealing cover material matched with the perforated plate is mostly made of imported aluminum foil or plastic coating products at present, the delivery period is long, the cost is high, and the huge requirements of the modern new coronavirus detection market cannot be met. Therefore, the technical problem to be solved by those skilled in the art is to design an easy-to-uncover cover film with environmental protection and excellent performance.

Disclosure of Invention

The invention provides a clean easy-to-tear cover film for liquid packaging, which overcomes the defects in the prior art and has the advantages of excellent chemical resistance, high peel strength, high tensile strength and excellent comprehensive performance in all aspects.

In order to achieve the purpose, the technical scheme of the invention is to provide a clean easy-to-open cover film for liquid packaging, which comprises an outer layer, an adhesive layer, an aluminum foil layer and an inner layer from outside to inside; the outer layer is made of paper; the adhesive layer comprises 5-10 parts of linear polysiloxane, 1-2 parts of cross-linking agent, 12-40 parts of epoxy resin, 4-17 parts of polyurethane and 0.5-1.5 parts of antioxidant; the inner layer comprises 15-60 parts of polyethylene glycol terephthalate-1, 4-cyclohexane dimethanol ester, 12-35 parts of polyvinyl chloride, 0.5-2 parts of plasticizer, 2-8 parts of polyacrylate, 0.3-0.5 part of curing agent, 0.1-0.4 part of smoothing agent and 2-6 parts of silicate.

The epoxy resin is a high molecular polymer and is a generic name of a polymer containing more than two epoxy groups in a molecule. The adhesive layer modifies the resin to achieve medical grade adhesive resin. The cover material does not need to be bonded by an adhesive, so that the solvent residue is effectively reduced. Has excellent chemical resistance and solvent resistance. The cross-linking agent is a substance with functional groups with different properties, and the molecular structure of the cross-linking agent is mainly characterized in that the molecule contains two groups with different chemical properties, one group is an inorganophilic group and is easy to chemically react with the surface of an inorganic substance; the other is an organophilic group which can chemically react with synthetic resins or other polymers or form hydrogen bonds to dissolve in the resin material, improving the properties of the adhesive layer, increasing the chemical and solvent resistance of the material, and at the same time increasing the tensile strength of the material. The crosslinking agent is one or more of polypropylene glycol glycidyl ether, zinc oxide and binaphthol.

The epoxy resin is one or more of epoxidized polybutadiene resin, triglycidyl cyanurate epoxy resin and bisphenol A type epoxy resin.

The material is heated and sheared to generate free radicals, and the free radicals generate peroxide free radicals when meeting oxygen or other chemical substances, and the peroxide free radicals further abstract hydrogen atoms from the main chain of the polymer to generate relatively stable polymer-based hydroperoxide. The cycle is repeated, the chain grows, and the reaction is gradually enlarged. The antioxidant consumes peroxide free radicals by providing H atoms or electrons, so that the hydrogen donor antioxidant for terminating the chain reaction is used, is mainly used for preventing or delaying the aging and deterioration of the film covering material, increases the tolerance of the material to chemical substances, has other components of a stable system, fully exerts a synergistic effect, and has effects on the retention of the peeling strength performance of the film covering material and the stability of the strength performance. The antioxidant extracted from biomass is selected, so that the antioxidant is friendly to human body and environment-friendly. The antioxidant is one or more of oryzanol, chlorophyll and theaflavin.

The plasticizer has excellent wear resistance and oil resistance, has enough resistance to oxygen, ozone, radiation and the like, increases the comprehensive performance of the material, has synergistic effect, ensures that the cover film has high tensile strength and elongation at break simultaneously, has excellent performances of small compression set, large bearing capacity and the like, increases the peel strength of the material, and generates good easy-to-open sealing effect. The plasticizer is one or more of dioctyl phthalate, butyl benzyl phthalate and di (2-ethyl) hexyl phthalate.

The inner layer of the easy-to-uncover sealing cover film is a functional layer, the flatness of the cover material is required to be high, and the curing agent is a substance for enhancing or controlling the curing reaction. The inner layer of the cover film is solidified through chemical reactions such as condensation, ring closure, addition or catalysis, so that the easy uncovering performance of the material is enhanced, and the flatness of the cover material is improved. The curing agent is one or more of butane diisocyanate, ketimine and 1, 5-naphthylene diisocyanate.

The smoothing agent is quite stable at normal temperature, and has excellent wettability, dispersibility, adhesiveness, thickening property, emulsifying property, water-retaining property and film-forming property, and impermeability to grease. The film formed by the smoothing agent has excellent toughness, flexibility and transparency, is nonionic, can be compatible with a plasticizer and a curing agent, keeps the liquid barrier property of the material, maintains stable mechanical property, promotes the cover film to be uncovered smoothly without pause and frustration, can realize differentiated control on the uncovering strength according to actual needs, and has stable solution in the pH range of 2-12. The smoothing agent is one or more of methylcellulose, Arabic gum and polyvidone.

The outer layer is 10-30 μm thick, the adhesive layer is 20-30 μm thick, and the inner layer is 10-20 μm thick.

The invention has the advantages and beneficial effects that: the water-based paint has excellent chemical resistance and solvent resistance, and the film is soaked in ethanol with the mass fraction of 95% and acetic acid with the mass fraction of 10% for covering films for 72 hours, so that the film body is complete, and no corrosion or leaching phenomenon is found. The easy-to-tear sealing strength is controllable, the peeling strength is high according to the formula customization, and the peeling strength is 4-8N/15mm under the condition of meeting the easy-to-tear condition. The flatness is high, and the sealing effect is uniform. The sterilization adaptability is wide, and the sterilization can meet the requirements of ethylene oxide or irradiation sterilization treatment. The physical properties of the mulch film are improved by improving the formula of the inner layer of the mulch film material and modifying the material of the bonding layer, and the tensile strength is more than or equal to 27 MPa. The product is pure, has good content resistance physical property, can improve the detection precision by 10 percent, has simple manufacturing process and wide market economic benefit. The invention has obvious cost advantage, excellent comprehensive performance in all aspects, strong industrialization capability, stable and controllable quality and stronger application prospect.

Detailed Description

The following further describes embodiments of the present invention with reference to examples. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

Example 1

A clean easy-to-open cover film for liquid packaging comprises an outer layer, an adhesive layer, an aluminum foil layer and an inner layer from outside to inside; the outer layer is made of paper; the bonding layer comprises 5 parts of linear polysiloxane, 1 part of cross-linking agent polypropylene glycol glycidyl ether, 12 parts of epoxidized polybutadiene resin, 4 parts of polyurethane and 0.5 part of antioxidant oryzanol; the inner layer comprises 15 parts of polyethylene glycol terephthalate-1, 4-cyclohexane dimethanol ester, 12 parts of polyvinyl chloride, 0.5 part of plasticizer dioctyl phthalate, 2 parts of polyacrylate, 0.3 part of curing agent butane diisocyanate, 0.1 part of smoothing agent methyl cellulose and 2 parts of silicate. The thickness of the outer layer is 10 μm, the thickness of the adhesive layer is 20 μm, and the thickness of the inner layer is 10 μm.

Example 2

A clean easy-to-open cover film for liquid packaging comprises an outer layer, an adhesive layer, an aluminum foil layer and an inner layer from outside to inside; the outer layer is made of paper; the bonding layer comprises 10 parts of linear polysiloxane, 2 parts of cross-linking agent zinc oxide, 40 parts of triglycidyl cyanurate epoxy resin, 17 parts of polyurethane and 1.5 parts of antioxidant chlorophyll; the inner layer comprises 60 parts of polyethylene terephthalate-1, 4-cyclohexane dimethanol ester, 35 parts of polyvinyl chloride, 2 parts of plasticizer butyl benzyl phthalate, 8 parts of polyacrylate, 0.5 part of curing agent ketimine, 0.4 part of smoothing agent Arabic gum and 6 parts of silicate. The thickness of the outer layer is 30 μm, the thickness of the adhesive layer is 30 μm, and the thickness of the inner layer is 20 μm.

Example 3

A clean easy-to-open cover film for liquid packaging comprises an outer layer, an adhesive layer, an aluminum foil layer and an inner layer from outside to inside; the outer layer is made of paper; the bonding layer comprises 8 parts of linear polysiloxane, 1 part of crosslinking agent binaphthol, 20 parts of bisphenol A epoxy resin, 10 parts of polyurethane and 1 part of antioxidant theaflavin; the inner layer comprises 30 parts of polyethylene glycol terephthalate-1, 4-cyclohexane dimethanol ester, 20 parts of polyvinyl chloride, 1 part of plasticizer phthalic acid di (2-ethyl) hexyl ester, 5 parts of polyacrylate, 0.4 part of curing agent 1, 5-naphthylene diisocyanate, 0.3 part of smoothing agent polyvidone and 4 parts of silicate. The thickness of the outer layer is 20 μm, the thickness of the adhesive layer is 25 μm, and the thickness of the inner layer is 15 μm.

Example 4

A clean easy-to-open cover film for liquid packaging comprises an outer layer, an adhesive layer, an aluminum foil layer and an inner layer from outside to inside; the outer layer is made of paper; the adhesive layer comprises 10 parts of linear polysiloxane, 1-2 parts of polypropylene glycol glycidyl ether wt%: the weight percent of zinc oxide is 1:3, 12 parts of epoxidized polybutadiene resin, 17 parts of polyurethane and 0.5 part of antioxidant chlorophyll; the inner layer comprises 60 parts of polyethylene glycol terephthalate-1, 4-cyclohexane dimethanol ester, 12 parts of polyvinyl chloride and 2 parts of dioctyl phthalate by weight percent: the plasticizer comprises 1:1 wt% of butyl benzyl phthalate, 2 parts of polyacrylate, 0.5 part of curing agent 1, 5-naphthylene diisocyanate, 0.1 part of smoothing agent povidone and 6 parts of silicate. The thickness of the outer layer is 10 μm, the thickness of the adhesive layer is 30 μm, and the thickness of the inner layer is 10 μm.

Example 5

A clean easy-to-open cover film for liquid packaging comprises an outer layer, an adhesive layer, an aluminum foil layer and an inner layer from outside to inside; the outer layer is made of paper; the adhesive layer comprises 6 parts of linear polysiloxane, 1 part of binaphthol serving as a cross-linking agent and 12-40 parts of triglycidyl isocyanurate epoxy resin in percentage by weight: the epoxy resin comprises 3:1 of bisphenol A epoxy resin in percentage by weight, 15 parts of polyurethane and 1.5 parts of antioxidant theaflavin; the inner layer comprises 50 parts of polyethylene glycol terephthalate-1, 4-cyclohexane dimethanol ester, 25 parts of polyvinyl chloride, 1.5 parts of plasticizer butyl benzyl phthalate, 6 parts of polyacrylate and 0.5 part of butane diisocyanate in percentage by weight: 1, 5-naphthylene diisocyanate, 0.2 part of smoothing agent Arabic gum and 5 parts of silicate. The thickness of the outer layer is 15 μm, the thickness of the adhesive layer is 20 μm, and the thickness of the inner layer is 20 μm.

Example 6

A clean easy-to-open cover film for liquid package comprises an outer layer, an adhesive layer, an aluminum foil layer and an inner layer from outside to inside; the outer layer is made of paper; the bonding layer comprises 5 parts of linear polysiloxane, 1 part of cross-linking agent polypropylene glycol glycidyl ether, 20 parts of bisphenol A epoxy resin, 12 parts of polyurethane and 0.5 part of oryzanol in percentage by weight: 1:1 of chlorophyll in weight percent; the inner layer comprises 45 parts of polyethylene glycol terephthalate-1, 4-cyclohexane dimethanol ester, 20 parts of polyvinyl chloride, 2 parts of plasticizer phthalic acid di (2-ethyl) hexyl ester, 3 parts of polyacrylate, 0.5 part of curing agent ketimine and 0.3 part of methyl cellulose by weight percent: smoothing agent with weight percent of Arabic gum being 1:2.5 and 5 parts of silicate. The outer layer is 10 μm thick, the adhesive layer is 20 μm thick, and the inner layer is 16 μm thick.

Comparative example

The comparative example is based on example 1 with the difference that no crosslinker was added in comparative example 1 and no plasticizer was added in comparative example 2.

1. Chemical resistance test results of inventive and comparative examples of examples 1-6

Soaking the cover film by using two extreme conditions of ethanol with the mass fraction of 95% and acetic acid with the mass fraction of 10%, and inspecting the chemical resistance of the cover film at 12h, 24h and 72 h. From the above table, it can be seen that under the conditions of high concentration solvent and strong acidity, the membrane body of the invention is complete after soaking for 72h, no corrosion is found, and no leaching phenomenon occurs. In comparative example 1, no crosslinking agent was added, the membrane integrity was maintained in 95% ethanol for 12 hours initially, and the membrane was delaminated and leached out by 24 hours. In 10% acetic acid, the film body is subjected to layer opening and leaching phenomena within 12h, and the chemical resistance of the cover film can be obviously enhanced by adding the cross-linking agent. In comparative example 2, no plasticizer is added into 95% ethanol, the film body can be kept intact for 24 hours, and the film body is delaminated and leached at 72 hours. In 10% acetic acid, the integrity of the film body can be maintained without leaching in the initial 12h, and the film body is delaminated and leached in the 24h, so that the addition of the plasticizer can also influence the chemical resistance of the mulch film material.

2. Inventive and comparative experimental results of examples 1-6

Test items	Peel strength (N/15mm)	Tensile Strength (MPa)
			Example 1	6	27.5
Example 2	4	28.2
			Example 3	7	27.6
Example 4	5	27.1
			Example 5	8	27.0
Example 6	7	27.4
			Comparative example 1	3	21.4
Comparative example 2	2	22.1

According to the invention, the peel strength is 4-8N/15mm, the peel strength is high, the easy-to-uncover requirement is met, the plasticizer is not added in the comparative example 2, the peel strength is smaller and is only 2N/15mm, the addition of the plasticizer can obviously increase the peel strength of the material, and the peel strength of the cover film in the comparative example 1 is also greatly reduced. The tensile strength of the films in the embodiments 1-6 is not less than 27MPa, the tensile strength of the film is greatly reduced when no cross-linking agent is added into the adhesive layer in the comparative example 1, the tensile strength of the film in the comparative example 2 is also obviously reduced, the modification of the materials of the adhesive layer and the inner layer of the cover film can be seen, and the tensile strength of the cover film can be greatly improved by adjusting related parameters and proportions, so that the performances of the materials in all aspects are improved.

In conclusion, the invention has excellent chemical resistance and solvent resistance, and the membrane body is complete without corrosion and leaching phenomenon after the membrane is soaked and covered by ethanol with the mass fraction of 95% and acetic acid with the mass fraction of 10% for 72 hours. The easy-to-tear sealing strength is controllable, the peeling strength is high according to the formula customization, and the peeling strength is 4-8N/15mm under the condition of meeting the easy-to-tear condition. The flatness is high, and the sealing effect is uniform. The sterilization adaptability is wide, and the sterilization can meet the requirements of ethylene oxide or irradiation sterilization treatment. The physical properties of the mulch film are improved by improving the formula of the inner layer of the mulch film material and modifying the material of the bonding layer, and the tensile strength is more than or equal to 27 MPa. The product is pure, has good content resistance physical property, can improve the detection precision by 10 percent, has simple manufacturing process and wide market economic benefit. The invention has obvious cost advantage, excellent comprehensive performance in all aspects, strong industrialization capability, stable and controllable quality and stronger application prospect.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the technical principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. A clean easy-to-open cover film for liquid packaging, which is characterized in that: the aluminum foil comprises an outer layer, an adhesive layer, an aluminum foil layer and an inner layer from outside to inside; the outer layer is made of paper; the adhesive layer comprises 5-10 parts of linear polysiloxane, 1-2 parts of cross-linking agent, 12-40 parts of epoxy resin, 4-17 parts of polyurethane and 0.5-1.5 parts of antioxidant; the inner layer comprises 15-60 parts of polyethylene glycol terephthalate-1, 4-cyclohexane dimethanol ester, 12-35 parts of polyvinyl chloride, 0.5-2 parts of plasticizer, 2-8 parts of polyacrylate, 0.3-0.5 part of curing agent, 0.1-0.4 part of smoothing agent and 2-6 parts of silicate.

2. A clean easy-open flap film for liquid packaging of claim 1, wherein: the cross-linking agent is one or more of polypropylene glycol glycidyl ether, zinc oxide and binaphthol.

3. A clean easy-open flap film for liquid packaging as claimed in claim 2, wherein: the epoxy resin is one or more of epoxidized polybutadiene resin, triglycidyl cyanurate epoxy resin and bisphenol A epoxy resin.

4. A clean easy-open flap film for liquid packaging of claim 3, wherein: the antioxidant is one or more of oryzanol, chlorophyll and theaflavin.

5. A clean easy-open flap film for liquid packaging of claim 4, wherein: the plasticizer is one or more of dioctyl phthalate, butyl benzyl phthalate and di (2-ethyl) hexyl phthalate.

6. A clean easy-open flap film for liquid packaging of claim 5, wherein: the curing agent is one or more of butane diisocyanate, ketimine and 1, 5-naphthylene diisocyanate.

7. A clean easy-open flap film for liquid packaging of claim 6, wherein: the smoothing agent is one or more of methylcellulose, acacia and polyvidone.

8. A clean easy-open flap film for liquid packaging of claim 7, wherein: the thickness of the outer layer is 10-30 μm, the thickness of the adhesive layer is 20-30 μm, and the thickness of the inner layer is 10-20 μm.