CN115648593A - Method for manufacturing packaging bottle with strippable inner layer - Google Patents

Abstract

The invention provides a manufacturing method of a packaging bottle with a strippable inner layer, belonging to the technical field of packaging. The problem that the manufacturing cost of the existing packaging bottle with the strippable inner layer made of a high-transparency material is high is solved. The invention is carried out according to the following sequence steps: the first step is as follows: forming a tube blank; respectively and independently injection-molding the inner pipe blank and the outer pipe blank in no sequence; the second step is that: assembling the tube blank; sleeving the outer pipe blank on the inner pipe blank before the outer pipe blank is cooled to room temperature; the third step: heating; heating the inner side and the outer side of the assembled tube blank simultaneously; the fourth step: blow molding; and (3) putting the heated tube blank into a blow molding die for blow molding to obtain the packaging bottle with the strippable inner layer. On the premise of ensuring that the packaging bottle is made of high-transparency materials and effectively controlling the amount of bubbles in the inner layer and the outer layer, the manufacturing difficulty is reduced, the requirements of manufacturing equipment are reduced, and the manufacturing cost of manufacturing the packaging bottle with the strippable inner layer by using the high-transparency materials is reduced by adjusting the manufacturing method of the tube blank for blow molding.

Description

Method for manufacturing packaging bottle with strippable inner layer

Technical Field

The invention belongs to the technical field of packaging, and relates to a manufacturing method of a packaging bottle, in particular to a manufacturing method of a packaging bottle with a strippable inner layer.

Background

The plastic bottle is a plastic container which is formed by blow molding, extrusion blowing or injection molding through a plastic mold, and is mainly made of polyethylene or polypropylene and other materials added with various organic solvents.

The inner layer strippable packaging bottle is characterized in that an inner container is arranged on the inner side of an outer container, the inner layer and the outer layer are arranged in a laminated mode, the inner layer can be stripped from the outer layer, when the packaging bottle is squeezed, the inner container with contents is squeezed to further spit out the contents, external air is guided between the inner container and the outer container after squeezing is relieved, the outer container is restored to the original state due to external air pressure, the inner container maintains a deformation state, and therefore the contents in the inner container are prevented from being deteriorated due to oxygen and the like contacting the external air.

The inner layer strippable packaging bottle is a packaging bottle with a multilayer structure, and when the packaging bottle is manufactured, a bottle blank with the multilayer structure is usually formed by co-extrusion and then is formed by blow molding; for example, a chinese patent application No. 201280038740.3 discloses a discharge container in which a container body is formed by blow molding a parison having a co-extruded two-layer structure. Polyethylene is generally used for the outer layer bottle and the inner container of the multi-container, and the container formed by extrusion blow molding of polyethylene has a problem that the transparency is poor and the inside is difficult to observe.

For this reason, it is conceivable to use a highly transparent material such as PET and to use an injection molded preform and then blow mold the container, such as the method for producing a peelable container and the apparatus for producing a peelable container disclosed in the chinese patent application No. 202080074363.3, in which the preform is injection molded, and the outer layer is injection molded first, and then the inner layer located inside the outer layer is injection molded; traditionally, preforms are made by a two shot injection molding process. The stripping container needs to be manufactured by adopting special equipment, so that the problems of high equipment purchase and maintenance cost, high technical difficulty, high manufacturing cost and the like exist.

Disclosure of Invention

The invention provides a manufacturing method of a packaging bottle with a strippable inner layer, which aims to solve the technical problem of reducing the manufacturing cost of manufacturing the packaging bottle with the strippable inner layer by adopting a high-transparency material.

The technical problem to be solved by the invention can be realized by the following technical scheme: the manufacturing method of the packaging bottle with the strippable inner layer is characterized by comprising the following steps in sequence: the first step is as follows: forming a tube blank; respectively and independently injection-molding an inner pipe blank and an outer pipe blank in no sequence; the second step is that: assembling the tube blank; sleeving the outer pipe blank on the inner pipe blank before the outer pipe blank is cooled to room temperature; the third step: heating; heating the inner side and the outer side of the assembled tube blank simultaneously; the fourth step: blow molding; and (3) putting the heated tube blank into a blow molding die for blow molding to obtain the packaging bottle with the strippable inner layer.

The inner pipe blank and the outer pipe blank are manufactured independently, obviously, the conventional injection molding machine and the conventional injection mold can be adopted for production, and the manufacturing cost is low. It is preferable to manufacture the inner shell first, and it is also permissible to store the inner shell for a long period of time after cooling, but the inner shell is usually already in a ready-to-assemble state when manufacturing the outer shell. The outer pipe blank is timely sleeved on the inner pipe blank after being demoulded from the die, and the characteristics of small deformation and expansion with heat and contraction with cold of the outer pipe blank which is not completely cooled are further utilized. Specifically, the deformation of the inner pipe blank and the outer pipe blank formed by injection molding is objective, and cannot be guaranteed to be completely consistent, so that the outer pipe blank generates small deformation along with the shape of the outer side surface of the inner pipe blank in the process of sleeving the outer pipe blank on the inner pipe blank, the goodness of fit of the outer side surface of the inner pipe blank and the inner side surface of the outer pipe blank is improved, the outer pipe blank is cooled and shrunk, and the goodness of fit of the outer side surface of the inner pipe blank and the inner side surface of the outer pipe blank is further improved. The cooling shrinkage of the outer pipe blank also enables the inner pipe blank and the outer pipe blank to be tightly matched and connected, so that the connection firmness between the inner pipe blank and the outer pipe blank is improved, and the possibility of movement and even falling off between the inner pipe blank and the outer pipe blank in the subsequent transportation process is avoided. Through improving the goodness of fit and the firm connection of inner tube blank and outer tube blank, the bubble generation amount between the inner layer and the outer layer in the blow molding process is reduced, and the attractiveness and the volume consistency of the packaging bottle are improved.

The outer tube blank and the inner tube blank are both suitable for PET, PP, LDPE, PC, PCTG or PETG; the outer tube blank and the inner tube blank are laminated by adopting a sleeving mode, so that the outer tube blank and the inner tube blank cannot be fused, the outer tube blank and the inner tube blank can be made of the same material, and the prepared packaging bottle not only has a strippable inner layer, but also has high transparency. The tube blank (prefabricated part) for blow molding is manufactured without adopting special equipment and a mould, so that the manufacturing cost of the tube blank is obviously reduced, and the manufacturing cost of the packaging bottle with the strippable inner layer is reduced.

In the third step, the inner side and the outer side of the tube blank are simultaneously heated, so that the temperature difference between the inner tube blank and the outer tube blank is obviously reduced, the occurrence rate of quality problems such as local whitening and molding failure of the packaging bottle is reduced, and the yield of the packaging bottle is improved.

As optimization, in the heating process of the third step, the outer tube blank is heated by infrared rays, and meanwhile, a constant-temperature heating rod is placed in the inner tube blank; the constant temperature heating rod plays an auxiliary heating role in the inner tube blank, and the internal and external temperature consistency of the assembled tube blank in the heating process is improved.

As optimization, the surface temperature of the constant-temperature heating rod is 80-110 ℃; the constant temperature heating rod in the temperature range further improves the temperature consistency of the inner tube blank and the outer tube blank.

Preferably, the outer tube blank comprises an outer tube main body and an outer tube opening, the inner tube blank comprises an inner tube main body, an inner tube opening and an inner tube turning part, the inner surface of the outer tube main body is matched with the outer surface of the inner tube main body, in the second step of assembling the tube blank, the outer tube main body is sleeved outside the inner tube main body, the outer tube opening is sleeved outside the inner tube opening, and the inner tube turning part is in contact with the top surface of the outer tube opening. And in the fourth step of blow molding, the outer tube main body and the inner tube main body are simultaneously blow molded, the outer tube main body is molded into the outer layer of the packaging bottle, the inner tube main body is molded into the inner layer of the packaging bottle, and the inner layer and the outer layer can be peeled off when the inner layer containing cavity is reduced. The outer tube body is used for blow molding the outer layer of a packaging bottle, and filling and capping of the packaging bottle are facilitated by arranging an outer tube opening part, for example, the outer tube opening part is provided with threads and an annular convex ring. The inner tube main part is used for the inlayer of blow molding packing bottle, and the contact of inner tube turn-over portion and the top surface of outer tube oral area not only avoids the inside slip of inner tube base in the blowing process, still reduces when the packing bottle uses between inlayer and the skin air through the oral area leak possibility.

As optimization, the outer pipe main body and the inner pipe main body are heated in the heating process of the third step; the outer pipe opening part and the inner pipe opening part are not actively heated, so that the outer pipe opening part and the inner pipe opening part are prevented from being deformed, and the consistency of the bottle opening of the packaging bottle is improved.

As optimization, an air inlet is formed in the outer pipe mouth part of the outer pipe blank; or the bottom surface of the outer tube blank is provided with an air inlet. The air inlet is processed in the process of injection molding of the outer pipe blank, so that in the assembling process, air between the inner pipe blank and the outer pipe blank can be exhausted through the air inlet, and the goodness of fit between the inner pipe blank and the outer pipe blank is obviously improved. When the packaging bottle is used, air enters the space between the outer layer and the inner layer through the air inlet, and a one-way air inlet structure for controlling the air to enter the space between the outer layer and the inner layer in a one-way mode can be arranged according to actual requirements.

Preferably, the center of the bottom surface of the outer tube blank is provided with an air inlet, the center of the bottom wall of the inner tube blank is provided with a connecting column, in the second step of assembling the tube blank, an air inlet valve plate is sleeved on the connecting column, then the outer tube blank is sleeved on the inner tube blank, and the connecting column penetrates through the air inlet of the outer tube blank.

Preferably, a one-way structure for limiting air between the outer layer and the inner layer to be discharged through the air inlet is formed between the air inlet valve plate and the bottom wall of the outer layer in the fourth step of blow molding, the part, located in the outer tube blank, of the connecting column is deformed to form a limiting part in the fourth step of blow molding, and the limiting part is used for limiting the separation of the central area of the bottom of the inner layer from the outer layer. The unidirectional structure is positioned between the outer layer and the inner layer, so that the unidirectional structure can be effectively protected; the one-way structure also has the advantages of simple structure, convenient manufacture and low manufacture cost, and further the manufacture cost of the packaging bottle can not be obviously influenced.

Compared with the prior art, the manufacturing method of the inner layer strippable packaging bottle is characterized in that the molded inner tube blank and the molded outer tube blank are assembled, then the assembled tube blank is molded into the packaging bottle through blow molding, an extrusion molding process is not adopted, and the outer tube blank and the inner tube blank are both made of high-transparency materials. According to the manufacturing method of the packaging bottle with the strippable inner layer, the inner side and the outer side of the tube blank are simultaneously heated in the process of blowing the tube blank, so that the problems of too low heating temperature of the inner tube blank or too high heating temperature of the outer tube blank are not easy to occur, and the inner temperature and the outer temperature of the assembled tube blank are consistent. On the premise of ensuring that the packaging bottle is made of high-transparency materials and effectively controlling the amount of bubbles in the inner layer and the outer layer, the manufacturing difficulty is reduced by adjusting the manufacturing method of the tube blank for blow molding, the requirements of manufacturing equipment are reduced, the purpose of reducing the manufacturing cost is achieved, and the manufacturing cost of manufacturing the packaging bottle with the strippable inner layer by using the high-transparency materials is further reduced.

Drawings

FIG. 1 is a schematic sectional view of an inner tube blank according to the first embodiment.

Fig. 2 is a schematic sectional structure diagram of the outer tube blank in the first embodiment.

FIG. 3 is a schematic sectional view showing the process of assembling the tube blank according to the first embodiment.

FIG. 4 is a schematic cross-sectional view of a blow molded preform according to one embodiment.

Fig. 5 is a schematic sectional view of a package bottle in the first embodiment.

FIG. 6 is a schematic sectional view of the inner tubular shell in the second embodiment.

FIG. 7 is a schematic sectional view of the outer tube blank in the second embodiment.

FIG. 8 is a schematic sectional view showing the structure of the tube blank assembling process in the second embodiment.

FIG. 9 is a schematic cross-sectional view of a blow molded preform according to a second embodiment.

Fig. 10 is a schematic sectional view of the packaging bottle in the second embodiment.

The labels in the figure are: 1. an inner tube blank; 1a, an inner tube main body; 1b, an inner pipe orifice part; 1c, an inner pipe edge turning part; 1d, connecting columns; 2. an outer tube blank; 2a, an outer tube body; 2b, an outer pipe opening part; 2c, screw thread; 2d, an annular convex ring; 2e, an air inlet; 3. a body portion; 4. a finish portion; 5. an inner layer; 6. an outer layer; 6a, a sealing area; 7. an air inlet valve plate; 8. a limiting part.

Detailed Description

The following are specific embodiments of the present invention and are further described with reference to the drawings, but the present invention is not limited to these embodiments.

The first embodiment is as follows: as shown in fig. 1 to 5, a method for manufacturing a package bottle with a peelable inner layer 5 is performed by the following steps in order: the first step is as follows: forming a tube blank; the second step is that: assembling the tube blank; the third step: heating; the fourth step: and (4) blow molding.

The first step is as follows: the formed tube blanks are respectively and independently injection-molded into an inner tube blank 1 and an outer tube blank 2 without sequencing. This example shows the inner tube blank 1 being injection moulded first and the outer tube blank 2 being injection moulded second. The outer pipe blank 2 is made of PET, PP, LDPE, PC, PCTG or PETG, and the inner pipe blank 1 is made of PET, PP, LDPE, PC, PCTG or PETG.

As shown in fig. 1, the inner tube blank 1 has a cylindrical shape and includes an inner tube main body 1a, an inner tube mouth portion 1b, and an inner tube turned-over portion 1c. As shown in fig. 2, the outer tube blank 2 includes an outer tube body 2a and an outer tube mouth 2b, the outer tube mouth 2b has a thread 2c and an annular convex ring 2d, and the outer tube mouth 2b has an air inlet 2e; the inner surface of the outer tube body 2a conforms to the outer surface of the inner tube body 1 a.

The second step: as shown in fig. 3 and 4, the assembled hollow shell is produced by fitting the outer tubular shell 2, which has been injection molded in the first step and has just been released from the mold, over the inner tubular shell 1 until the top surface of the outer tubular mouth portion 2b comes into contact with the inner tubular turned-over portion 1c. Specifically, the inner tube blank 1 is positioned, the opening of the inner tube blank 1 faces downwards, and the inner tube blank 1 is sleeved and positioned on the positioning column, so that the position and the state of the inner tube blank 1 are accurately positioned, and the subsequent mechanical arm sleeving machining is convenient; the outer tube blank 2 is then put with its end facing downwards, and the outer tube blank 2 is fitted over the inner tube blank 1 in the direction indicated by the arrow shown in fig. 3; air in the outer tube blank 2 can be discharged through the port and the air inlet 2e in the process that the outer tube blank 2 is sleeved on the inner tube blank 1.

The temperature of the outer pipe blank 2 immediately after being released from the mold is not necessarily cooled to room temperature, and the temperature of the outer pipe blank 2 is preferably 50 ℃ to 80 ℃, for example, 50 ℃, 55 ℃, 60 ℃, 65 ℃, 70 ℃, 75 ℃ and 80 ℃; the hardness of the outer tube blank 2 in the temperature state is moderate, the outer tube blank 2 is suitable for being clamped by a manipulator, the clamping firmness and stability are guaranteed, the outer tube blank 2 is slightly deformed along with the shape of the outer side surface of the inner tube blank 1 in the process that the outer tube blank 2 is sleeved on the inner tube blank 1, and the goodness of fit between the outer side surface of the inner tube blank 1 and the inner side surface of the outer tube blank 2 is improved.

The assembled tube blank is also called a blow molding prefabricated member, and according to the actual production working condition, the heating and blow molding can be directly carried out before the blow molding prefabricated member is not cooled, or the heating and blow molding can be carried out after the blow molding prefabricated member is naturally cooled and transported to other areas.

The third step, heating is to gradually heat the outer tube body 2a and the inner tube body 1a of the blow preform to a set temperature. Specifically, the heating device includes an infrared heating channel and a constant temperature heating rod, the port of the blow-molded preform faces upward, and only the lower region of the annular flange 2d is inserted into the infrared heating channel by holding the annular flange 2d, thereby infrared-heating the outer tube body 2a of the outer tube blank 2, and of course the inner tube body 1a is also infrared-heated. The constant-temperature heating rod is used for assisting in heating the inner tube main body 1a, and the surface temperature of the constant-temperature heating rod is 80-110 ℃; the constant temperature heating rod goes into from the port of blow molding prefab, and the constant temperature heating rod has the location cap portion, and the side of location cap portion contacts with the port medial surface of blow molding prefab and forms the location, and then makes the constant temperature heating rod be located the inner chamber central zone of blow molding prefab, and the terminal surface of location cap portion contacts with the port terminal surface of blow molding prefab, and then makes the constant temperature heating rod depth of insertion unanimous, realizes improving the heating temperature uniformity from this.

The fourth step: in the blow molding, the blow molded prefabricated part heated in the third step is placed in a blow molding mould, and compressed air is blown in to form the bottle body part 3 of the packaging bottle in the lower area of the annular convex ring 2d in the blow molded prefabricated part; the outer tubular opening 2b of the outer tubular blank 2 serves as a mouth portion 4 of the packing bottle. From the internal and external structures, the inner tube blank 1 is blow molded into the inner layer 5 of the packaging bottle, the outer tube blank 2 is blow molded into the outer layer 6 of the packaging bottle, and the air inlet 2e is used for allowing air to enter the space between the inner layer 5 and the outer layer 6 of the bottle body part 3.

Example two: as shown in fig. 6 to 10, the structure and principle of the present embodiment are substantially the same as those of the first embodiment, and the substantially same points are not described redundantly, but only different points are described, where: the center of the bottom wall of the injection-molded inner tube blank 1 is provided with a connecting column 1d, and the center of the bottom surface of the injection-molded outer tube blank 2 is provided with an air inlet 2e.

In the second step of assembling the tube blank, the outer tube blank 2 is sleeved on the inner tube blank 1, and the connecting column 1d is sleeved with the air inlet valve plate 7 before; the connecting column 1d passes through the air inlet 2e of the outer tube blank 2 in the sleeving process.

In a blow molding packaging bottle, a one-way structure for limiting air between the outer layer 6 and the inner layer 5 to be discharged through the air inlet 2e is formed between the air inlet valve plate 7 and the bottom wall of the outer layer 6; specifically, the bottom wall of the outer layer 6 is provided with a sealing area 6a for contacting the outer edge of the air inlet valve sheet 7, when the air pressure of the space between the outer layer 6 and the inner layer 5 is lower than the external air pressure, the air pressure forces the air inlet valve sheet 7 to deform, and then the air enters the space between the outer layer 6 and the inner layer 5 through the air inlet 2e; when the bottle body part 3 is squeezed, the air pressure in the space between the outer layer 6 and the inner layer 5 is larger than the air pressure outside, so that the air inlet valve plate 7 is forced to be attached to the sealing area 6a, the air discharge amount in the space between the outer layer 6 and the inner layer 5 is obviously reduced, and the air pressure in the space between the outer layer 6 and the inner layer 5 is kept stable.

In the fourth step of blow molding, the part, located on the outer tube blank 2, of the connecting column 1d is deformed to form a limiting part 8, and the limiting part 8 is used for limiting the separation of the central area of the bottom of the inner layer 5 from the outer layer 6.

Claims (10)

1. The manufacturing method of the packaging bottle with the strippable inner layer is characterized by comprising the following steps in sequence:

the first step is as follows: forming a tube blank; respectively and independently injection-molding an inner pipe blank (1) and an outer pipe blank (2) without sequencing;

the second step is that: assembling the tube blank; sleeving the outer tube blank (2) on the inner tube blank (1) before the outer tube blank (2) is cooled to room temperature;

the third step: heating; simultaneously heating the inner side and the outer side of the assembled tube blank;

the fourth step: blow molding; and (3) putting the heated tube blank into a blow molding die for blow molding to obtain the packaging bottle with the strippable inner layer.

2. The manufacturing method of the inside-layer peelable packaging bottle according to claim 1, wherein the material of the outer tube blank (2) is PET, PP, LDPE, PC, PCTG or PETG; the inner tube blank (1) is made of PET, PP, LDPE, PC, PCTG or PETG.

3. The method of manufacturing an inside-peelable packaging bottle according to claim 1, wherein in the heating of the third step, the outer tubular blank (2) is heated by infrared rays while a constant temperature heating rod is placed in the inner tubular blank (1).

4. The method for manufacturing the packaging bottle with the peelable inner layer according to claim 3, wherein the surface temperature of the constant temperature heating bar is 80 ℃ to 110 ℃.

5. The method of manufacturing a package bottle with peelable inner layer according to claim 1, 2, 3 or 4, wherein the outer tube blank (2) comprises an outer tube main body (2 a) and an outer tube mouth portion (2 b), the inner tube blank (1) comprises an inner tube main body (1 a), an inner tube mouth portion (1 b) and an inner tube flange portion (1 c), the inner surface of the outer tube main body (2 a) is fitted to the outer surface of the inner tube main body (1 a), the outer tube main body (2 a) is fitted to the outer tube main body (1 a), the outer tube mouth portion (2 b) is fitted to the inner tube mouth portion (1 b), and the inner tube flange portion (1 c) is in contact with the top surface of the outer tube mouth portion (2 b).

6. The manufacturing method of the inside peeling type packaging bottle as set forth in claim 5, wherein the heating of the third step heats the outer tube main body (2 a) and the inner tube main body (1 a).

7. The method of manufacturing a packing bottle with peelable inner layer according to claim 5, wherein the outer tube body (2 a) and the inner tube body (1 a) are blow molded simultaneously in the fourth step, the outer tube body (2 a) is molded as the outer layer (6) of the packing bottle, the inner tube body (1 a) is molded as the inner layer (5) of the packing bottle, and the inner layer (5) and the outer layer (6) are peelable when the cavity of the inner layer (5) is reduced.

8. The manufacturing method of the inner layer peelable packaging bottle according to claim 5, wherein an air inlet (2 e) is provided in the outer tube blank (2) at the outer tube mouth portion (2 b); or the bottom surface of the outer pipe blank (2) is provided with an air inlet (2 e).

9. The manufacturing method of the inner-layer peelable packaging bottle according to claim 8, wherein an air inlet (2 e) is formed in the center of the bottom surface of the outer tube blank (2), a connecting column (1 d) is formed in the center of the bottom wall of the inner tube blank (1), in the second step of assembling the tube blank, an air inlet valve plate (7) is sleeved on the connecting column (1 d), the outer tube blank (2) is sleeved on the inner tube blank (1), and the connecting column (1 d) penetrates through the air inlet (2 e) of the outer tube blank (2).

10. The method for manufacturing a packaging bottle with peelable inner layer according to claim 9, wherein a one-way structure for restricting air between the outer layer (6) and the inner layer (5) from being discharged through the air inlet (2 e) is formed between the air inlet valve sheet (7) and the bottom wall of the outer layer (6) in the fourth step of blow molding, and a stopper portion (8) for restricting separation of the central region of the bottom of the inner layer (5) from the outer layer (6) is further formed by deforming the connecting post (1 d) at the portion of the outer tube blank (2) in the fourth step of blow molding.

Images