CN113152143B - Preparation method of anti-seepage paper bottle - Google Patents

Abstract

The invention relates to a preparation method of an anti-seepage paper bottle, which comprises the following steps: (1) placing paper pulp and other auxiliary agents into a pulp blending tank and uniformly stirring to obtain pulp; (2) conveying the slurry into a forming machine, installing a paper bottle mold, immersing the paper bottle mold into the slurry, forming through vacuum adsorption, and then demolding to obtain a wet blank of a paper bottle; (3) drying the wet blank of the paper bottle to obtain a blank of the paper bottle; (4) film coating and shaping: spraying a film spraying agent on the inner wall of a paper bottle blank, then placing the paper bottle blank into a heated shaping die, then injecting hot compressed air into the shaping die, carrying out crosslinking on the inner wall surface of the paper bottle by the film spraying agent under the heating action of the hot compressed air to form an anti-seepage adhesive film, and simultaneously enabling the shape of the bottle body to be completely attached to the shape of the shaping die by the pressure of the hot compressed air, thereby finally obtaining the anti-seepage paper bottle product. The method can form the anti-seepage glue film which is uniformly covered in the shaping process of the paper bottle, and the anti-seepage performance of the obtained paper bottle is better while the production efficiency is improved.

Description

Preparation method of anti-seepage paper bottle

Technical Field

The invention relates to the technical field of paper product production, in particular to a preparation method of an anti-seepage paper bottle.

Background

With the stricter and stricter environmental protection requirements, the non-degradable products such as disposable cups, plates, lunch boxes, packaging materials and the like which are used in the past belong to the forbidden use at present, and the effective substitute is a paper molding product. In some industrially developed countries, pulp molded products account for up to 70% of the weight of the product in the field of industrial product packaging.

Pulp molded articles can be divided into two broad fields depending on the application, namely food articles and industrial packaging articles. The raw material requirements for the two types of articles differ: a great amount of annual herbaceous plant pulp is used as a main raw material for food products, while waste paper recycled pulp is mainly used as an industrial packaging product, or annual herbaceous fiber and a certain proportion of original pulp are used as raw materials for production. The production line has the working principle that the required paper pulp is prepared after physical or chemical treatment, and is conveyed to a forming machine after the concentration is adjusted. The forming machine is provided with a product mold, paper pulp is adsorbed by vacuum and is continuously filtered, the adsorbed pre-dried and formed wet product (wet blank) is unloaded by means of a compression period and a vacuum device, and then the wet product is placed on a hot die for hot-pressing drying and forming or is placed on a conveyor belt, conveyed into a drying oven for drying, and then is shaped after drying.

The typical production process of the pulp molding product comprises pulping, molding, heating and shaping, drying, trimming, surface sizing, sterilizing and packaging. If the surface sizing is carried out on the food product, special food glue is generally applied to the inner surface of the shaped product, and then hot air drying or far infrared ray drying is carried out to form a glue film, the glue film has the advantages of oil resistance, water resistance and high temperature resistance, meets the food sanitation standard and can be naturally degraded, but the process operation is complex, the technical difficulty is high, and the leakage of the product caused by uneven sizing is easy to generate.

Disclosure of Invention

In order to solve the technical problem of leakage caused by uneven sizing after conventional shaping, the preparation method of the anti-seepage paper bottle is provided. The method can form the anti-seepage glue film in the shaping process of the paper bottle, improve the production efficiency, and simultaneously obtain the anti-seepage paper bottle with better anti-seepage performance and uniform anti-seepage glue film coverage.

In order to achieve the purpose, the invention is realized by the following technical scheme:

the preparation method of the impermeable paper bottle comprises the following steps:

(1) pulping: placing paper pulp and other auxiliary agents into a pulp blending tank and uniformly stirring to obtain pulp;

(2) molding: conveying the slurry into a forming machine, installing a paper bottle mold, immersing the paper bottle mold into the slurry, forming through vacuum adsorption, and then demolding to obtain a wet blank of a paper bottle;

(3) and (3) drying: drying the wet paper bottle blank to obtain a paper bottle blank;

(4) film coating and shaping: spraying a film spraying agent on the inner wall of the paper bottle blank, humidifying and softening the paper bottle blank by water in the film spraying agent, then putting the paper bottle blank after humidification and softening into a heated shaping die, then injecting hot compressed air into the paper bottle blank after humidification and softening in the shaping die for shaping, so that the water in the paper bottle blank after humidification and softening and the water in the film spraying agent are evaporated, and the water evaporation process of the film spraying agent is crosslinked on the surface of the inner wall of the paper bottle blank under the heating action of the hot compressed air to form an anti-seepage adhesive film, and simultaneously, the shape of the paper bottle blank is completely attached to the shape of the shaping die by means of pressure blowing support of the compressed air, and finally, the anti-seepage paper bottle is obtained.

Further, in the step (1); the paper pulp adopts herbaceous plant raw pulp and/or waste paper regenerated pulp; the other auxiliary agents comprise a binder, a waterproof agent and a release agent; the pulp comprises the following pulp and other auxiliary agents in parts by weight: 70-90% of paper pulp, 2-8% of binder, 1-20% of waterproofing agent and 1-15% of release agent.

Furthermore, the binder is one or two of starch slurry and bentonite with the concentration of 8-20 wt%, and has the function of preventing sedimentation; the waterproof agent is neutral for papermaking; the release agent is zinc stearate.

Further, the water content of the paper bottle blank after drying in the step (3) is 5% -10%.

Further, the heating temperature of the shaping die in the step (4) is 160-180 ℃; the pressure of the hot compressed air is 0.6MPa to 3MPa, and the temperature is 160 ℃ to 180 ℃; the shaping time is 2 min-5 min.

Further, the heating temperature of the shaping die in the step (4) is 180 ℃; the pressure of the hot compressed air is 2MPa, and the temperature is 160 ℃.

Further, the film spraying agent in the step (4) comprises the following raw materials in parts by weight: 4-7% of gelatin, 2-5% of oxidized starch, 0.5-1.5% of guar gum and the balance of water; the molecular structure of the oxidized starch has carboxylic acid groups on side chains. The principle of forming the anti-seepage adhesive film by the laminating agent is as follows: heating compressed air is introduced into the heated sizing die, on one hand, the pressure of the compressed air presses the bottle blank to the sizing die, so that the bottle blank is attached to the die, and the paper bottle with the smooth inner and outer surfaces after being sized can be obtained; on the other hand, the hot compressed air at 160-170 ℃ can ensure that gelatin in the film spraying agent is firstly dehydrated to form an amido bond, a peptide chain (amido bond) in the gelatin, a hydrophilic group on the peptide chain and hydroxyl on a guanidine gum molecular chain are crosslinked with carboxyl of oxidized starch under the thermal action, dehydration cyclization is carried out, a crosslinked product is bonded with paper fiber in a paper bottle blank in the process of water evaporation, namely a crosslinked anti-seepage adhesive film is obtained on the surface of the inner wall of the bottle, the anti-seepage adhesive film can form a uniformly covered film layer under the pressure of compressed air, and the anti-seepage adhesive film obtained after crosslinking ensures that the interior of the paper bottle has better water resistance and oil resistance, and the anti-seepage effect is obvious. In addition, the added guanidine gum has better thickening effect and oil displacement effect.

Further, the anti-seepage paper bottle is directly used in the industrial product packaging industry, or used in the food product industry and the cosmetic product industry after being sterilized;

if the impermeable paper bottle is used in the food product industry and the cosmetic product industry, the paper pulp adopts herbal protoplasm, and the raw materials of the film spraying agent and the pulp adopt food-grade raw materials;

if the anti-seepage paper bottle is used in the industrial product packaging industry, the paper pulp adopts herbaceous plant raw pulp and/or waste paper recycled pulp, and the raw materials of the film spraying agent and the pulp adopt industrial raw materials.

The beneficial technical effects are as follows:

according to the method, the steps of film coating and shaping are combined into a whole in the preparation process of the paper bottle, heated compressed air is introduced into a heated shaping die, on one hand, the pressure of the compressed air presses the bottle blank humidified by the film coating agent to the shaping die, so that the bottle blank is attached to the die, and the paper bottle with a smooth surface after shaping can be obtained; on the other hand, the thermal effect of the hot compressed air can enable the laminating agent to be crosslinked, the pressure of the hot compressed air can enable the laminating agent to form an evenly covered film layer in the bottle wall, after water is evaporated, an evenly covered and crosslinked anti-seepage adhesive film is obtained on the inner wall of the bottle, and the anti-seepage adhesive film obtained after crosslinking enables the interior of the paper bottle to have better water resistance and oil resistance, so that the anti-seepage effect is obvious; in addition, the raw materials adopted by the laminating agent are all water-soluble high polymer materials, so that the laminating agent is degradable, non-toxic and harmless and meets the requirements of food products; the method shortens the production steps of the paper bottles, improves the production efficiency and has simple operation.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Unless specifically stated otherwise, the numerical values set forth in these examples do not limit the scope of the invention. Techniques, methods known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

The experimental methods of the following examples, which are not specified under specific conditions, are generally determined according to national standards; if no corresponding national standard exists, the method is carried out according to the universal international standard or the standard requirement proposed by related enterprises. Unless otherwise indicated, all parts are parts by weight and all percentages are percentages by weight.

Example 1

The preparation method of the impermeable paper bottle comprises the following steps:

(1) pulping: putting a mixture of 80% of herbaceous plant primary pulp, 10% of starch slurry and bentonite as a binder 5% (the mass ratio of the starch slurry to the bentonite is 1:1), 8% of a neutral papermaking waterproofing agent and 7% of a zinc stearate release agent into a pulp mixing tank according to the proportion, and uniformly stirring to obtain a slurry;

(2) molding: conveying the slurry into a forming machine, installing a paper bottle mold, immersing the paper bottle mold into the slurry, forming through vacuum adsorption, and then demolding to obtain a wet blank of a paper bottle;

(3) and (3) drying: drying the wet paper bottle blank to obtain a paper bottle blank, wherein the water content of the paper bottle blank is 5% -10%; the drying can be performed by high-temperature circulating hot air;

(4) film coating and shaping: spraying a film spraying agent on the inner wall of the paper bottle blank, humidifying and softening the paper bottle blank by virtue of moisture in the sprayed film spraying agent, then putting the paper bottle blank after humidifying and softening into a shaping die at 180 ℃, then injecting hot compressed air with the pressure of 2MPa and the temperature of 160 ℃ into the shaping die for shaping for 3min, so that the moisture in the paper bottle blank after humidifying and softening and the moisture in the film spraying agent are evaporated under the heating action of the hot compressed air, and the film spraying agent is crosslinked in the process of moisture evaporation to form an anti-seepage adhesive film on the inner wall surface of the paper bottle blank, and simultaneously blowing and supporting by virtue of the pressure of the compressed air so that the bottle body shape of the paper bottle blank is completely attached to the shape of the shaping die, thereby finally obtaining the anti-seepage paper bottle.

Wherein the film spraying agent comprises the following raw materials in parts by weight: 5% of gelatin, 3% of oxidized starch with carboxylic acid groups on the side chains of the molecular structure, 1% of guar gum and the balance of water, and the raw materials are mixed and dissolved in water to form uniform mixed liquid, so that the spraying is convenient.

The principle of forming the anti-seepage adhesive film by the laminating agent is as follows: heating compressed air is introduced into the heated sizing die, on one hand, the pressure of the compressed air presses the bottle blank to the sizing die, so that the bottle blank is attached to the die, and the paper bottle with the smooth inner and outer surfaces after being sized can be obtained; on the other hand, the hot compressed air at 160 ℃ can ensure that gelatin in the film spraying agent is firstly dehydrated to form an amido bond, a peptide chain (amido bond) in the gelatin, a hydrophilic group on the peptide chain and hydroxyl on a guanidine gum molecular chain are crosslinked with carboxyl of oxidized starch under the thermal action, dehydration and cyclization are carried out, a crosslinked product is bonded with paper fiber in a paper bottle blank in the process of water evaporation, namely a crosslinked anti-seepage adhesive film is obtained on the surface of the inner wall of the bottle, the anti-seepage adhesive film can form a uniformly covered film layer under the pressure of compressed air, and the anti-seepage adhesive film obtained after crosslinking ensures that the interior of the paper bottle has better water resistance and oil resistance, and the anti-seepage effect is obvious. In addition, the added guanidine gum has better thickening effect and oil displacement effect.

The anti-seepage paper bottle prepared by the embodiment can be used in the food industry and the cosmetic product industry after being sterilized, and the raw materials of the slurry and the laminating agent are all edible raw materials.

Example 2

The preparation method of the impermeable paper bottle comprises the following steps:

(1) pulping: putting 70% of herbaceous plant raw pulp, 15% of a mixture of starch slurry and bentonite serving as 8% of a binder (the mass ratio of the starch slurry to the bentonite is 1:1), 7% of a neutral papermaking waterproofing agent and 15% of a zinc stearate release agent into a pulp mixing pool according to a ratio, and uniformly stirring to obtain a slurry;

(2) molding: conveying the slurry into a forming machine, installing a paper bottle mold, immersing the paper bottle mold into the slurry, forming through vacuum adsorption, and then demolding to obtain a wet blank of a paper bottle;

(3) and (3) drying: drying the wet paper bottle blank to obtain a paper bottle blank, wherein the water content of the paper bottle blank is 5% -10%; the drying can be performed by high-temperature circulating hot air;

(4) film coating and shaping: spraying a film spraying agent on the inner wall of the paper bottle blank, humidifying and softening the paper bottle blank by means of moisture in the film spraying agent, then putting the paper bottle blank after being humidified and softened into a shaping die at 180 ℃, then injecting hot compressed air with the pressure of 2MPa and the temperature of 160 ℃ into the shaping die for shaping for 3min, crosslinking the film spraying agent on the inner wall surface of the paper bottle blank under the heating action of the hot compressed air to form an anti-seepage adhesive film, and simultaneously blowing and supporting by means of the pressure of the compressed air to enable the bottle body shape of the paper bottle blank to be completely attached to the shape of the shaping die, thereby finally obtaining the anti-seepage paper bottle product.

Wherein the film spraying agent comprises the following raw materials in parts by weight: 6% of gelatin, 2% of oxidized starch with carboxylic acid groups on the side chains of the molecular structure, 0.5% of guar gum and the balance of water, and the raw materials are mixed and dissolved in water to form uniform mixed liquid, so that the spraying is convenient.

The anti-seepage paper bottle prepared by the embodiment can be used in the food product industry and the cosmetic product industry after being sterilized, and the raw materials of the slurry and the laminating agent are all edible raw materials.

Example 3

The preparation method of the impermeable paper bottle comprises the following steps:

(1) pulping: putting 90% of waste paper regenerated pulp, 15 wt% of mixture of starch pulp and bentonite as a binder 2% (the mass ratio of the starch pulp to the bentonite is 1:1), 3% of neutral papermaking waterproofing agent and 5% of zinc stearate release agent into a pulp mixing tank according to the proportion, and uniformly stirring to obtain pulp;

(2) molding: conveying the slurry into a forming machine, installing a paper bottle mold, immersing the paper bottle mold into the slurry, forming through vacuum adsorption, and then demolding to obtain a wet blank of a paper bottle;

(3) and (3) drying: drying the wet paper bottle blank to obtain a paper bottle blank, wherein the water content of the paper bottle blank is 5% -10%; the drying can be performed by high-temperature circulating hot air;

(4) film coating and shaping: spraying a film spraying agent on the inner wall of the paper bottle blank, humidifying and softening the paper bottle blank by means of moisture in the film spraying agent, then putting the paper bottle blank after being humidified and softened into a shaping die at 180 ℃, then injecting hot compressed air with the pressure of 2MPa and the temperature of 160 ℃ into the shaping die for shaping for 3min, crosslinking the film spraying agent on the inner wall surface of the paper bottle blank under the heating action of the hot compressed air to form an anti-seepage adhesive film, and simultaneously blowing and supporting by means of the pressure of the compressed air to enable the bottle body shape of the paper bottle blank to be completely attached to the shape of the shaping die, thereby finally obtaining the anti-seepage paper bottle product.

Wherein the film spraying agent comprises the following raw materials in parts by weight: 7% of gelatin, 4% of oxidized starch with carboxylic acid groups on the side chains of the molecular structure, 1.5% of guar gum and the balance of water, and the raw materials are mixed and dissolved in water to form uniform mixed liquid, so that the spraying is convenient.

The anti-seepage paper bottle prepared by the embodiment is directly used in the industrial product packaging industry, and the raw materials of the slurry and the laminating agent are all industrial raw materials.

The paper bottle of the above example was subjected to a performance test, with reference to GB/T36392-2018. The specific data are shown in Table 1.

Table 1 paper bottle performance data for the examples

As can be seen from Table 1, the COBB value of the paper bottle without film coating is higher, and the water absorption is better, but the COBB value of the paper bottle with the film coated on the surface is very low, which indicates that the paper bottle with the film coated on the surface has better water resistance, and the water-soluble raw materials in the film coating agent are successfully crosslinked from the side, so that a water-insoluble crosslinked film layer is formed, and no leakage exists after the film coating. The contact angle of the paper bottle without the film is hydrophilic, the contact angles of the adhesive films on the surface of the paper bottle after film coating are all larger than 90 degrees, the inner surface of the paper bottle after film coating has certain hydrophobicity, the waterproof effect is good, and the inner wall of the paper bottle also has certain oil resistance due to certain oil displacement of guanidine gum. The laminating agent disclosed by the invention is low in film coating amount, and under the condition of low film coating amount, the paper bottle disclosed by the invention has better water resistance, water resistance and oil resistance.

If the impermeable paper bottle is used in the food product industry and the cosmetic product industry, the raw materials adopted in the manufacturing process of the impermeable paper bottle are all edible raw materials, such as a waterproof agent, a film coating agent and the like, and if the impermeable paper bottle is used in the industrial product industry, the raw materials adopt industrial grade, and the paper pulp adopts waste paper recycled pulp. The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered as the technical solutions and the inventive concepts of the present invention within the technical scope of the present invention.

Claims (6)

1. The preparation method of the impermeable paper bottle is characterized by comprising the following steps:

(1) pulping: placing paper pulp and other auxiliary agents into a pulp blending tank and uniformly stirring to obtain pulp;

(2) molding: conveying the slurry into a forming machine, installing a paper bottle mold, immersing the paper bottle mold into the slurry, forming through vacuum adsorption, and then demolding to obtain a wet blank of a paper bottle;

(3) and (3) drying: drying the wet paper bottle blank to obtain a paper bottle blank;

(4) film coating and shaping: spraying a film spraying agent on the inner wall of the paper bottle blank, humidifying and softening the paper bottle blank by water in the film spraying agent, then putting the paper bottle blank after humidification and softening into a heated shaping die, then injecting hot compressed air into the paper bottle blank after humidification and softening in the shaping die for shaping, crosslinking the film spraying agent on the inner wall surface of the bottle body of the paper bottle blank under the heating action of the hot compressed air to form an anti-seepage film, and simultaneously blowing and supporting by the pressure of the hot compressed air to ensure that the shape of the bottle body of the paper bottle blank is completely attached to the shape of the shaping die, thereby finally obtaining the anti-seepage paper bottle;

the heating temperature of the shaping die in the step (4) is 160-180 ℃; the pressure of the hot compressed air is 0.6 MPa-3 MPa, and the temperature is 160 ℃ to 180 ℃; the shaping time is 2 min-5 min;

the film spraying agent in the step (4) comprises the following raw materials in parts by weight: 4-7% of gelatin, 2-5% of oxidized starch, 0.5-1.5% of guanidine gum and the balance of water; the molecular structure of the oxidized starch has carboxylic acid groups on side chains.

2. The method for preparing the impermeable paper bottle as claimed in claim 1, wherein the pulp in step (1) is herbal puree and/or waste paper recycled pulp; the other auxiliary agents comprise a binder, a waterproof agent and a release agent;

the pulp comprises the following paper pulp and other auxiliary agents in parts by weight: 70-90% of paper pulp, 2-8% of binder, 1-20% of waterproof agent and 1-15% of release agent.

3. The method for preparing the impermeable paper bottle as claimed in claim 2, wherein the binder is one or two of starch slurry and bentonite with a concentration of 8-20 wt%; the water-proofing agent is neutral for papermaking; the release agent is zinc stearate.

4. The method for preparing the impermeable paper bottle as claimed in claim 1, wherein the moisture content of the blank of the paper bottle after drying in the step (3) is 5-10%.

5. The method for preparing impermeable paper bottles as claimed in claim 1, wherein the heating temperature of the shaping die in the step (4) is 180 ℃; the pressure of the hot compressed air is 2MPa, and the temperature is 160 ℃.

6. The method for preparing the impermeable paper bottle as claimed in claim 1, wherein the impermeable paper bottle is directly used in industrial product packaging industry, or is used in food product industry and cosmetic product industry after being sterilized;

if the impermeable paper bottle is used in the food product industry and the cosmetic product industry, the paper pulp adopts herbal protoplasm, and the raw materials of the film spraying agent and the pulp adopt food-grade raw materials;

if the anti-seepage paper bottle is used in the industrial product packaging industry, the paper pulp adopts herbaceous plant raw pulp and/or waste paper recycled pulp, and the raw materials of the film spraying agent and the pulp adopt industrial raw materials.