A high barrier coating for paper blisters and a method for its preparation, paper blister material

Abstract

The application belongs to the technical field of packaging materials, and particularly relates to a high-barrier coating for a paper blister, a preparation method of the high-barrier coating and a paper blister material. The high-barrier coating for the paper blister is prepared by performing corona treatment on a paper base, then depositing polylysine and bentonite in layers on the surface of the paper base, finally forming a polylysine / bentonite composite layer with a labyrinth effect, densifying the paper, and then coating a film composed of polylactic acid, tea tree oil, acetyl tri-butyl citrate, hydroxypropyl methyl cellulose and Span 80 on the surface of the polylysine / bentonite composite layer, so that the gas barrier property, hydrophobicity and antibacterial and antioxidant property of the paper blister are further improved. Finally, the paper blister material prepared in the application has excellent moisture resistance, high gas barrier property such as oxygen and water vapor, and suitable breaking resistance.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of packaging materials, and particularly relates to a high-barrier coating for a paper blister and a preparation method thereof and a paper blister material. BACKGROUND

[0002] Medical and food blister (PTP) packaging has a wide range of applications. The cover film material of the traditional PTP is mainly aluminum foil. Although the aluminum foil has superior barrier properties, there are still many shortcomings in the actual operation process: (1) a large number of pinholes are easily generated near the blister of the aluminum foil after being packaged by an automatic packaging machine, which leads to poor barrier properties such as water resistance and air permeation resistance; (2) the brittle fracture of the aluminum foil blister patch is obvious, and the brittle fracture of the adjacent blister patch is particularly prone to occur due to folding, peeling and other actions during use or acquisition, which affects the storage performance of the packaging; (3) the production and printing process of aluminum is complex, the cost is high, and the pollution is large, which are obvious defects of the product; (4) there are safety hazards of aluminum film cutting or tablet fragmentation during use.

[0003] At present, the cover film of the blister packaging for medicine, medical treatment or food mainly adopts a combination of a protective layer, aluminum foil and a heat-sealing layer to improve the barrier property of the blister packaging. The protective layer is generally selected from biaxially oriented polypropylene, polyethylene terephthalate and nylon to alleviate the defects of the traditional PTP cover film. Although the barrier property of the blister is improved, the natural degradation period of the above-mentioned materials is long, and the aluminum plastic composite affects the recycling of the aluminum foil.

[0004] At present, the blister packaging has begun to promote in the direction of non-PVC and non-PVDC, but there is no corresponding product in the cover film market, and the performance is relatively single. SUMMARY

[0005] In order to further improve the barrier property and environmental protection of the paper blister, the application provides a high-barrier coating for a paper blister, a preparation method thereof and a paper blister material.

[0006] The application first provides a preparation method of a high-barrier coating for a paper blister, which comprises the following steps: S1, performing corona treatment on both sides of a paper base to obtain a corona-treated paper base; S2, immersing the corona-treated paper base in a polylysine solution and a bentonite suspension in sequence to complete primary deposition; S3, immersing the corona-treated paper base after the primary deposition in the polylysine solution and the bentonite suspension in sequence and alternately to complete N times of deposition, and then immersing the corona-treated paper base in the polylysine solution once to obtain a deposited paper base; and S4, coating a polylactic acid mixture on one side of the deposited paper base, and solidifying and drying to obtain a high-barrier coating.

[0007] Further, the polylysine solution is prepared by the following method: dissolving polylysine in acetic acid aqueous solution, stirring and dissolving, adjusting the pH value to 6, filtering, and obtaining the polylysine solution.

[0008] Further, the polylysine and the acetic acid aqueous solution are used in a ratio of (1-2) g:(500-800) mL; and the acetic acid aqueous solution has a volume concentration of 0.20-0.25%.

[0009] Further, the bentonite suspension is prepared by the following method: dispersing bentonite in deionized water, stirring by magnetic force and homogenizing under high pressure, standing, collecting the upper clear liquid, and obtaining the bentonite suspension; and the bentonite and the deionized water are used in a ratio of (1-2) g:(500-1000) mL.

[0010] Further, the soaking time in each of the S2 and S3 is 4-7 min.

[0011] Further, N in the S3 is 20-40.

[0012] Further, the polylactic acid mixed solution is prepared by the following method: dissolving polylactic acid in dichloromethane, adding tea tree oil, acetyl tri-butyl citrate, hydroxypropyl methyl cellulose and Span 80, and mixing uniformly to obtain the polylactic acid solution.

[0013] Further, the polylactic acid, dichloromethane, tea tree oil, acetyl tri-butyl citrate, hydroxypropyl methyl cellulose and Span 80 are used in a ratio of (5-10) g:(100-200) mL:(0.5-1.2) g:(0.5-3) g:(0.02-0.1) g:(0.1-1) g.

[0014] The application also provides a high-barrier coating for a paper blister, which is prepared by the above preparation method.

[0015] The application also provides a paper blister material, which comprises the above high-barrier coating and a thick paper layer; one side of the high-barrier coating without polylactic acid is an inner side, the inner side of the high-barrier coating is combined with one side of the thick paper layer through glue, and the other side of the thick paper layer is coated with a heat-sealing glue.

[0016] Compared with the prior art, the application has the following beneficial effects:

[0017] 1、The application forms a labyrinth effect and densifies the paper by depositing polylysine and bentonite layer by layer on the surface of the paper base, and finally forming a polylysine / bentonite composite layer, thereby improving the gas barrier property of the paper base. Then, a film composed of polylactic acid, tea tree oil, acetyl tri-butyl citrate, hydroxypropyl methyl cellulose and Span 80 is coated on the surface of the polylysine / bentonite composite layer, further improving the gas barrier property, hydrophobicity and antibacterial and antioxidant properties of the paper bubble.

[0018] 2、The paper bubble of the application has excellent moisture resistance, high gas barrier property of oxygen and water vapor, and suitable breaking force.

[0019] 3、The paper bubble of the application has the characteristics of green, environmental protection and biodegradability, which greatly reduces the microplastic pollution in the life cycle. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The figure is a material structure diagram of the paper bubble of the application, wherein 1 is a high barrier coating layer; 2 is glue; 3 is a thick paper layer; and 4 is a heat-seal glue. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only some of the embodiments of the application, but not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the application.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0023] In the case of using "include", "have", and "contain" described herein, it is intended to cover non-exclusive inclusion, unless the explicit limiting term such as "only", "consisting of", etc. is used, otherwise another component can be added.

[0024] The words "preferably," "more preferably," "most preferably," and the like, in the specification, mean that in certain situations, one embodiment can provide certain benefits, however, other embodiments can also be preferred for the same reasons or for other reasons. Also, the use of these terms does not foreclose from the scope of the application other embodiments that can not include certain of the benefits and features.

[0025] In the specification, the use of the term "further," "furthermore," "in addition," and the like, are used in the sense of "additionally" and not in the sense of "only." Thus, the use of these terms does not foreclose from the scope of the application other embodiments that can not include certain of the benefits and features.

[0026] In the specification, the use of the term "at least" followed by a number of an item, means that the number of the item is one or more. For example, "at least two" means one or more than one. In the specification, the use of the term "at least one" followed by a world, means that the world appears one or more times. For example, "at least one R" means one or more R.

[0027] When a range of values is disclosed, unless otherwise explicitly provided, each intervening value between the ranges end points is also included. The same applies to ranges of integral values. In addition, it is intended that the disclosure encompassing any and all subranges between the minimum and maximum values provided in the range. It is intended that where this disclosure includes a range, the range is inclusive of the minimum and maximum values, and further encompassing each intervening value.

[0028] Unless otherwise expressly specified, all steps of the application can be performed in any order. For example, the method comprising steps (a) and (b) means that the method can comprise steps (a) and (b) in sequence, or steps (b) and (a) in sequence. For example, the method can further comprise step (c) means that step (c) can be added to the method in any order, for example, the method can comprise steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc. Unless otherwise indicated, a singular form of a term can include a plural form of that term, and vice versa. Unless otherwise indicated, the use of "or" means "and / or", that is, the use of "or" in the English language typically indicates a selective disjunction.

[0029] In the specification, the use of "above" or "below" includes the number itself. For example, 1 or below includes 1.

[0030] In the face of the current blister lid film environmental effect is not good, aluminum plastic composite leads to aluminum recycling difficult predicament, the present application through a large number of experimental research, provide a kind of for paper bubble high barrier coating and its preparation method, paper bubble material, improve the barrier properties of paper bubble by coating method.The present application is first on paper base is subjected to corona treatment, paper base is subjected to corona treatment after, surface roughness and adhesion increase, and paper base surface presents electronegativity, then placed in acidic polylysine solution, polylysine is protonated in acidic solution, so that the entire molecular chain is positively charged, by electrostatic attraction, firmly adsorbed on the surface of the paper base with negative electricity, then placed in bentonite suspension, negatively charged bentonite nanosheet will be strongly attracted by the positively charged polylysine layer, complete the initial deposition. Such alternation, finally get polylysine / bentonite composite layer, form a labyrinth effect, and densification of paper, increase the difficulty of gas molecule penetration. In order to further improve the hydrophobicity and antibacterial antioxidant of coating, a layer of film composed of polylactic acid, tea tree oil, acetyl tri-butyl citrate, hydroxypropyl methyl cellulose and Span80 is coated on the surface of the polylysine / bentonite composite layer. The synergistic effect of the degradable polylactic acid film and the polylysine / bentonite composite layer further improves the gas and liquid barrier properties of the paper bubble.

[0031] In some embodiments of the present application, a method for preparing a high barrier coating for a paper bubble includes the following steps: S1, corona treatment is performed on both sides of the paper base to obtain a corona-treated paper base; S2, the corona-treated paper base is sequentially immersed in a polylysine solution and a bentonite suspension to complete the initial deposition; S3, the corona-treated paper base after the initial deposition is immersed in the polylysine solution and the bentonite suspension alternately for N times of deposition, and then immersed in the polylysine solution once to obtain a deposited paper base; and S4, a polylactic acid mixture is coated on one side of the deposited paper base, and then solidified and dried to obtain a high barrier coating.

[0032] In some embodiments of the present application, in step S2, the polylysine solution is prepared by the following method: polylysine is dissolved in an acetic acid aqueous solution, stirred and dissolved, the pH value is adjusted to 6, and then filtered to obtain a polylysine solution; and the volume concentration of the acetic acid aqueous solution is 0.20-0.25%.

[0033] In some specific embodiments of the present application, the ratio of the amount of polylysine to the amount of acetic acid aqueous solution can be (1-2) g:(500-800) mL; typically but not limitedly, for example, it can be 1 g:500 mL, 1.5 g:650 mL or 2 g:800 mL.

[0034] Through the pH value regulation research of the acetic acid aqueous solution, it is found that when the pH value of the acetic acid aqueous solution is 6, the ionization degree of polylysine is relatively low, the molecular chain is in a random coil conformation, the repulsive force is small, the single-layer deposition is thicker, the surface roughness is increased, and the subsequent bentonite loading capacity is improved.

[0035] In some embodiments of the present application, in step S2, the bentonite suspension is prepared by dispersing sodium-based bentonite in deionized water, stirring by magnetic force and high-pressure homogenization, then standing, collecting the upper clear liquid as the bentonite suspension.

[0036] In some specific embodiments of the present application, the ratio of bentonite to deionized water is (1-2) g: (500-1000) mL; typically but not limitedly, for example, it can be 1 g:500 mL, 1.5 g:750 mL, 2 g:1000 mL.

[0037] By multiple high-pressure homogenization treatment of bentonite, the degree of exfoliation is significantly improved, and the average particle size is greatly reduced, which is more conducive to the highly directional arrangement of bentonite layers on the paper base.

[0038] In some specific embodiments of the present application, the soaking time of each time is 4-7 min; typically but not limitedly, for example, it can be 4 min, 5 min, 6 min, 7 min.

[0039] In some specific embodiments of the present application, in step S3, N is 20-40; typically but not limitedly, for example, it can be 20, 22, 24, 26, 28, 30.

[0040] Through the study of the number of deposited layers, it is found that the barrier performance of the paper bubble cap material in the range of N=20-40 is the best, and the burst resistance is appropriate. With further increase of the number of deposited layers, the barrier performance does not improve obviously, and the burst resistance decreases instead.

[0041] In some embodiments of the present application, in step S4, the polylactic acid mixed solution is prepared by dissolving polylactic acid in dichloromethane, adding tea tree oil, acetyl tri-butyl citrate, hydroxypropyl methyl cellulose and Span 80, and mixing uniformly to obtain a polylactic acid solution.

[0042] In some specific embodiments of the present application, in step S4, the ratio of polylactic acid, dichloromethane, tea tree oil, acetyl tri-butyl citrate, hydroxypropyl methyl cellulose, and Span 80 is (5-10) g: (100-200) mL: (0.5-1.2) g: (0.5-3) g: (0.02-0.1) g: (0.1-1) g; typically but not limitedly, for example, it can be 5 g:100 mL:0.5 g:0.5 g:0.02 g:0.1 g, 7.5 g:150 mL:0.8 g:1.5 g:0.06 g:0.5 g, 10 g:200 mL:1.2 g:3 g:0.1 g:1 g.

[0043] Since polylysine itself has hydrophilicity, it will be plasticized under high humidity, resulting in that the overall water vapor transmission rate performance is not obviously improved. The polylactic acid emulsion composed of polylactic acid, dichloromethane, tea tree oil, acetyl tri-butyl citrate, and hydroxypropyl methyl cellulose is coated on the surface of the deposited paper base. On the one hand, the hydrophobicity of polylactic acid can effectively block the transmission of water vapor, and after coating polylactic acid, the water vapor transmission rate will be significantly reduced. On the other hand, tea tree oil has broad-spectrum antibacterial and antioxidant activity, and can improve the antibacterial activity of the paper blister material when combined with polylactic acid. At the same time, hydrogen bonds and hydrophobic interactions are formed between tea tree oil and polylactic acid molecules, which restrict the movement of polylactic acid molecular chains and improve the thermal stability of the paper blister material.

[0044] The paper blister material of the present application comprises the above high barrier coating layer and thick paper layer. The side of the high barrier coating layer without polylactic acid is the inner side, and the inner side of the high barrier coating layer is combined with one side of the thick paper layer through glue. The other side of the thick paper layer is coated with a heat-seal adhesive.

[0045] The paper used in the thick paper layer can be white cardboard with a weight of 100-300 gsm, preferably white cardboard with a weight of 200 gsm.

[0046] In some embodiments of the present application, the glue can be a polyurethane adhesive.

[0047] In some embodiments of the present application, the heat-seal adhesive can be a VC adhesive.

[0048] The present application will be further described below by way of examples, but the scope of the present application is not limited thereto.

[0049] When numerical ranges are given, it is understood that every numerical range encompassing the lower and upper bounds of the range is contemplated, unless otherwise indicated. Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as commonly understood by one of ordinary skill in the art. Unless otherwise specified, the conditions in the examples are carried out under conventional conditions or manufacturer's recommended conditions. All reagents or instruments not specified by the manufacturer are conventional products that can be purchased on the market. In addition to the specific methods, devices, and materials used in the examples, any method, device, and material similar or equivalent to those described in the examples of the present application can also be used to implement the present application based on the mastery of the prior art by those skilled in the art and the description of the present application.

[0050] Example 1

[0051] A method for preparing a high barrier coating layer for a paper blister, comprising the following steps:

[0052] S1, both sides of the paper base (white card, 50gsm) were treated by a corona treater (corona parameters: voltage: 12kV; frequency: 70Hz; power: 0.5kW; current: 0.06A), the distance between the electrode and the surface of the paper base was 1.2cm, and the paper base passed through the corona discharge area at a speed of 400mm / min, and the treated paper base was obtained after the treatment;

[0053] S2.1, preparation of polylysine solution: 1g of polylysine was dissolved in 500mL of 0.20% acetic acid aqueous solution, stirred until completely dissolved, then 1mol / L sodium hydroxide solution was used to adjust the pH value of the system to 6, filtered with filter paper to remove undissolved impurities, and a polylysine solution was obtained;

[0054] S2.2, preparation of bentonite suspension: 1g of bentonite was dispersed in 500mL of deionized water, magnetically stirred at a speed of 600r / min for 3 days, then treated by a high-pressure homogenizer (4000psi) for 5 times, and then placed for 24h, and the upper clear liquid was collected, which was the bentonite suspension;

[0055] S2.3, the corona-treated paper base was soaked in the polylysine solution for 4min, taken out, washed with deionized water, then soaked in the bentonite suspension for 4min, taken out, washed with deionized water, and dried, and the primary deposition was completed;

[0056] S3, the corona-treated paper base after the primary deposition was subjected to the operation of step S2.3 for 19 times, and 20 depositions were completed, then soaked in the polylysine solution for 4min, taken out, washed with deionized water, and dried, and the deposited paper base was obtained;

[0057] S4, preparation of polylactic acid mixture: polylactic acid was dissolved in 100mL of dichloromethane, tea tree oil, acetyl citric acid tributyl ester, hydroxypropyl methyl cellulose and Span80 (the amount ratio of polylactic acid, dichloromethane, tea tree oil, acetyl citric acid tributyl ester, hydroxypropyl methyl cellulose and Span80 was 5g:100mL:0.5g:0.5g:0.02g:0.1g) were added, and mixed uniformly, and a polylactic acid mixture was obtained;

[0058] The deposited paper base was fixed on a coating machine, a 50μm metering rod was used to coat the polylactic acid mixture on one side of the deposited paper base at a coating speed of 5m / min, and then dried and solidified at 50℃ for 3h, and a high-barrier coating layer was obtained.

[0059] Example 2

[0060] A preparation method of a high-barrier coating for a paper blister, comprising the following steps:

[0061] S1, both sides of the paper base (white card, 70gsm) were treated by a corona treater (corona parameters: voltage: 12kV; frequency: 70Hz; power: 0.5kW; current: 0.06A), the distance between the electrode and the surface of the paper base was 1.2cm, and the paper base passed through the corona discharge area at a speed of 400mm / min, and the treated paper base was obtained after the treatment;

[0062] S2.1, preparation of polylysine solution: polylysine 1.5g was dissolved in 650mL of 0.22% acetic acid aqueous solution, stirred until completely dissolved, then 1mol / L sodium hydroxide solution was used to adjust the pH value of the system to 6, filtered with filter paper to remove undissolved impurities, and a polylysine solution was obtained;

[0063] S2.2, preparation of bentonite suspension: bentonite 1.5g was dispersed in 750mL of deionized water, magnetically stirred at a speed of 700r / min for 3 days, then treated by a high-pressure homogenizer (4000psi) for 5 times, and then placed for 24h, and the upper clear liquid was collected, which was the bentonite suspension;

[0064] S2.3, the corona-treated paper base was soaked in the polylysine solution for 5min, taken out, washed with deionized water, then soaked in the bentonite suspension for 5min, taken out, washed with deionized water, and dried, and the primary deposition was completed;

[0065] S3, the corona-treated paper base after the primary deposition was repeated for 29 times of the operation of step S2.3, and 30 depositions were completed, then soaked in the polylysine solution for 5min, taken out, washed with deionized water, and dried, and the deposited paper base was obtained;

[0066] S4, preparation of polylactic acid mixture: polylactic acid was dissolved in dichloromethane, tea tree oil, acetyl citric acid tributyl ester, hydroxypropyl methyl cellulose and Span80 (the amount ratio of polylactic acid, dichloromethane, tea tree oil, acetyl citric acid tributyl ester, hydroxypropyl methyl cellulose and Span80 was 8g: 150mL: 0.8g: 1.5g: 0.06g: 0.5g) were added, and mixed uniformly to obtain a polylactic acid mixture;

[0067] The deposited paper base was fixed on a coating machine, a 50μm metering rod was used to coat the polylactic acid mixture on one side of the deposited paper base at a coating speed of 5m / min, and then dried and solidified at 50℃ for 4h to obtain a high-barrier coating layer.

[0068] Example 3

[0069] A preparation method of a high-barrier coating for a paper blister, comprising the following steps:

[0070] S1, both sides of the paper base (white card, 80gsm) were treated by a corona treater (corona parameters: voltage: 12kV; frequency: 70Hz; power: 0.5kW; current: 0.06A), the distance between the electrode and the surface of the paper base was 1.2cm, and the paper base passed through the corona discharge area at a speed of 400mm / min, after the treatment, the corona-treated paper base was obtained;

[0071] S2.1, preparation of polylysine solution: 2g of polylysine was dissolved in 800mL of 0.25% acetic acid aqueous solution, stirred until completely dissolved, then 1mol / L sodium hydroxide solution was used to adjust the pH value of the system to 6, filtered with filter paper to remove undissolved impurities, and the polylysine solution was obtained;

[0072] S2.2, preparation of bentonite suspension: 2g of bentonite was dispersed in 1000mL of deionized water, magnetically stirred at a speed of 800r / min for 3 days, then treated by a high-pressure homogenizer (4000psi) for 5 times, and then placed for 24h, the upper clear liquid was collected, which was the bentonite suspension;

[0073] S2.3, the corona-treated paper base was soaked in the polylysine solution for 7min, taken out, washed with deionized water, then soaked in the bentonite suspension for 7min, taken out, washed with deionized water, and dried, to complete the first deposition;

[0074] S3, the corona-treated paper base after the first deposition was repeated the operation of step S2.3 for 39 times, to complete 40 depositions, then soaked in the polylysine solution for 7min, taken out, washed with deionized water, and dried, to obtain the deposited paper base;

[0075] S4, preparation of polylactic acid mixture: the polylactic acid was dissolved in dichloromethane, tea tree oil, acetyl citric acid tributyl ester, hydroxypropyl methyl cellulose and Span80 (the amount ratio of polylactic acid, dichloromethane, tea tree oil, acetyl citric acid tributyl ester, hydroxypropyl methyl cellulose and Span80 was 10g:200mL:1.2g:3g:0.1g:1g) were added, and mixed uniformly, to obtain the polylactic acid mixture;

[0076] The deposited paper base was fixed on a coating machine, a 50μm metering rod was used to coat the polylactic acid mixture on one side of the deposited paper base at a coating speed of 5m / min, and then dried and solidified at 50℃ for 5h, to obtain a high-barrier coating layer.

[0077] A paper blister material, as shown in Figure 1 The paper blister material of the present application comprises the above high-barrier coating layer 1 and a thick paper layer 3; the side of the high-barrier coating layer 1 without polylactic acid is the inner side, the inner side of the high-barrier coating layer 1 and one side of the thick paper layer 3 are compounded by glue 2, and the other side of the thick paper layer 3 is coated with heat-seal glue 4.

[0078] Control 1

[0079] The same as example 3, except that the deposited paper base is used as a high barrier coating.

[0080] Control 2

[0081] The same as example 3, except that the paper base is used instead of a high barrier coating.

[0082] Performance testing

[0083] The paper blister materials prepared in examples 1-3 and controls 1-2 were tested for oxygen transmission rate (OTR) and water vapor transmission rate (W) performance, and the results are shown in Table 1.

[0084]

[0085] As can be seen from Table 1, the paper blister materials prepared in examples 1-3 have high gas barrier properties for oxygen and water vapor, and suitable burst resistance.

[0086] The paper blister materials prepared in examples 1-3 were tested for water absorption (Cobb (1800s)) according to TAPPI T441, and it was found that the Cobb (1800s) values of the paper blister materials of examples 1-3 were less than 0.5 g / m 2 , proving that they have excellent moisture resistance.

[0087] Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements to some of the technical features, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for the preparation of a high barrier coating for paper blisters, characterized by: It comprises the following steps: S1, the paper base is treated by corona on both sides to obtain a corona treated paper base; S2, the corona treated paper base is sequentially immersed in a polylysine solution and a bentonite suspension to complete a primary deposition; S3, the corona treated paper base after the primary deposition is sequentially immersed in the polylysine solution and the bentonite suspension to complete N times of deposition, and then immersed in the polylysine solution once again to obtain a deposited paper base; S4, a polylactic acid mixture is coated on one side of the deposited paper base, and then solidified and dried to obtain a high-barrier coating layer. In the S2 and S3, the immersion time of each time is 4-7 min. In the S3, N is 20-40. In the S4, the polylactic acid mixture is prepared by the following method: polylactic acid is dissolved in dichloromethane, tea tree oil, acetyl tri-butyl citrate, hydroxypropyl methyl cellulose and Span80 are added, and then mixed uniformly to obtain a polylactic acid solution. In the S4, the amount ratio of polylactic acid, dichloromethane, tea tree oil, acetyl tri-butyl citrate, hydroxypropyl methyl cellulose and Span80 is (5-10) g: (100-200) mL: (0.5-1.2) g: (0.5-3) g: (0.02-0.1) g: (0.1-1) g.

2. The process for the preparation of a high barrier coating for paper blisters according to claim 1, characterized by: In the S2, the polylysine solution is prepared by the following method: polylysine is dissolved in an aqueous acetic acid solution, stirred and dissolved, the pH value is adjusted to 6, and then filtered to obtain a polylysine solution.

3. The process for the preparation of a high barrier coating for paper blisters according to claim 2, characterized by: In the S2, the amount ratio of polylysine and aqueous acetic acid solution is (1-2) g: (500-800) mL; the volume concentration of the aqueous acetic acid solution is 0.20-0.25%.

4. The process for the preparation of high barrier coating for paper blisters according to claim 1, characterized by: In the S2, the bentonite suspension is prepared by the following method: bentonite is dispersed in deionized water, and then subjected to magnetic stirring and high-pressure homogenization, and then left to stand, and the upper clear liquid is collected as the bentonite suspension; the amount ratio of bentonite and deionized water is (1-2) g: (500-1000) mL.

5. A high barrier coating for paper blisters, characterized by: The preparation method is prepared by any one of claims 1-4.

6. A paper blister material characterized by: It comprises the high-barrier coating layer and the thick paper layer as claimed in claim 5; the side of the high-barrier coating layer without polylactic acid is the inner side, the inner side of the high-barrier coating layer and one side of the thick paper layer are compounded by glue, and the other side of the thick paper layer is coated with a heat-sealing glue.

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