A co-extrusion blown film die and a co-extrusion blown film suitable for cold-stretching sleeve film

Abstract

The utility model discloses a kind of co-extrusion blown film die and co-extrusion blown film suitable for cold-drawing bushing film, including die body, extrusion runner and at least two layer runners. Extrusion runner is set to the die body, the annular extrusion outlet is provided with in the extrusion runner one end around first axis, the other end of the extrusion runner is provided with annular inlet around the first axis;At least two layer runners each the layer runner is arranged outward along the radial direction of the first axis, the layer runner is provided with annular discharge port, the annular discharge port is communicated with the annular inlet;Wherein at least one layer runner is configured as composite layer runner, remaining layer runner is configured as single layer runner, the composite layer runner includes at least two sub runners, the sub runner has sub inlet and sub discharge port, all the sub discharge ports of the same composite layer runner are arranged around the first axis and sequentially communicated to form corresponding annular discharge port.

Description

Technical Field

[0001] This utility model relates to co-extrusion blown film, and particularly to a co-extrusion blown film die head and a co-extrusion blown film. Background Technology

[0002] Blow molding machines use co-extrusion blown film dies to extrude molten material for subsequent blown film production. Existing co-extrusion blown film dies include a die body, extrusion channels, and multiple layered channels. These layered channels are arranged radially outward along a first axis of the die body, and their annular outlets are connected to the annular inlets of the extrusion channels. Each layered channel can receive molten material of different materials. The layered channels ultimately disperse the molten material into annular layers within the extrusion channels, causing the multiple molten material streams to flow in layers within the extrusion channels and finally extrude a co-extruded blown film at the annular extrusion outlet. The film is then blown to a specified thickness using the blown film method. However, this type of co-extrusion blown film die produces co-extruded blown films, such as cold-drawn sleeve films, where the material of each individual annular blown film layer is entirely the same. This limits the production of more diverse co-extruded blown films, resulting in insufficient versatility, and the production cost of co-extruded blown films is relatively high. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a co-extrusion blown film die head suitable for cold-stretched sleeve films, which can produce more diverse co-extrusion blown films and improve versatility.

[0004] This utility model also proposes a co-extrusion blown film produced by the above-mentioned co-extrusion blown film die.

[0005] According to a first aspect embodiment of the present invention, a co-extrusion blown film die includes a die body, an extrusion channel, and at least two laminar flow channels. The extrusion channel is disposed on the die body, with an annular extrusion port at one end surrounding a first axis and an annular inlet at the other end surrounding the first axis. Each of the at least two laminar flow channels is arranged radially outward along the first axis, and each laminar flow channel has an annular discharge port connected to the annular inlet. At least one laminar flow channel is configured as a composite laminar flow channel, and the remaining laminar flow channels are configured as single laminar flow channels. Each composite laminar flow channel includes at least two sub-channels, each sub-channel having a sub-inlet and a sub-outlet. All sub-outlets located within the same composite laminar flow channel are arranged around the first axis and sequentially connected to form a corresponding annular discharge port.

[0006] According to the first aspect of the present invention, the co-extrusion blown film die head has at least the following beneficial effects: one or more of the laminar flow channels are composite laminar flow channels, and the composite laminar flow channel includes two or more sub-flow channels. Each sub-flow channel can be used for the flow of molten material of one material. The outlets of all sub-flow channels of the same composite laminar flow channel are sequentially connected around the first axis to form an annular discharge port. That is, the annular flow from the annular discharge port can be in the form of two or more materials spliced ​​together, so that the co-extrusion blown film head can produce a variety of co-extrusion blown films, can flexibly combine the materials of the annular blown film layer, improve versatility, and reduce the production cost of co-extrusion blown films.

[0007] According to some embodiments of the present invention, a diffusion section is provided at one end of the sub-channel near the sub-outlet, the width of the diffusion section gradually increases along the direction near the sub-outlet, and the end of the diffusion section forms the sub-outlet.

[0008] According to some embodiments of the present invention, the diffusion section is trapezoidal or triangular.

[0009] According to some embodiments of the present invention, the monomer layer flow channel includes a spiral section and an annular section. One end of the spiral section is a monomer inlet. The spiral section is arranged around the first axis, and the annular section is arranged around the first axis. The spiral section and the annular section are connected, and the annular section is provided with the annular outlet.

[0010] According to some embodiments of the present invention, the cross-sectional area of ​​the spiral segment gradually increases along the direction close to the annular discharge port.

[0011] According to some embodiments of the present invention, the composite layer flow channel includes at least four sub-flow channels, some of which are configured as first sub-flow channels and the remaining sub-flow channels are configured as second sub-flow channels. The number of first sub-flow channels and second sub-flow channels is the same. The first sub-flow channels and second sub-flow channels are arranged alternately around the first axis. The first sub-flow channels and second sub-flow channels are respectively used to transport material flows of different materials.

[0012] According to some embodiments of the present invention, the die head body includes a distribution section and an extrusion section. The distribution section includes at least three die blocks that are sequentially nested radially outward along the first axis. The laminar flow channel is formed between two adjacent die blocks. The extrusion section forms the extrusion flow channel and is connected to one end of the distribution section.

[0013] According to the second aspect of the present invention, the co-extrusion blown film is produced by the co-extrusion blown film die head suitable for cold stretching sleeve film described above, including at least two stacked annular blown film layers, at least one of the annular blown film layers being a composite blown film layer, and the remaining annular blown film layers being monolithic blown film layers. The composite blown film layer includes an elastomer POE segment and a PE segment, and the elastomer POE segment and the PE segment are arranged and connected around the central axis of the annular blown film layer.

[0014] According to the second aspect of the present invention, the co-extrusion blown film has at least the following beneficial effects: the co-extrusion blown film can form a structure of splicing two materials at the composite blown film layer, which is conducive to combining the advantages of the corresponding materials and avoiding the disadvantages of the corresponding materials, so that the co-extrusion blown film produced has better performance and lower cost.

[0015] According to some embodiments of the present invention, at least two POE segments and at least two PE segments are provided, the number of POE segments and PE segments is the same, and the POE segments and PE segments are alternately arranged and connected around the central axis of the annular blown film layer.

[0016] According to some embodiments of the present invention, the annular blown film layer is provided with five layers, the third annular blown film layer is the composite blown film layer, and the remaining annular blown film layers are the monomer blown film layers.

[0017] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0019] Figure 1 This is a three-dimensional schematic diagram of a co-extrusion blown film die head according to an embodiment of the present utility model;

[0020] Figure 2 This is a three-dimensional schematic diagram of the distribution section of the co-extrusion blown film die head according to an embodiment of the present utility model;

[0021] Figure 3 The embodiments of this utility model are as follows Figure 1 A cross-sectional view along the AA direction;

[0022] Figure 4 This is an exploded view of the distribution section of the co-extrusion blown film die head according to an embodiment of the present invention;

[0023] Figure 5 This is a schematic diagram of the composite layer flow channel according to an embodiment of the present invention;

[0024] Figure 6 This is a schematic diagram of a single-layer flow channel according to an embodiment of the present invention;

[0025] Figure 7 This is a cross-sectional schematic diagram of a co-extruded blown film according to an embodiment of the present invention.

[0026] Figure label:

[0027] Die head body 100, distribution part 110, die block 111, extrusion part 120;

[0028] Extrusion channel 200, annular extrusion port 210, annular inlet port 220;

[0029] Laminar flow channel 300, annular outlet 301, composite laminar flow channel 310, sub-flow channel 311, diffuser section 3111, direct flow section 3112, first sub-flow channel 3113, second sub-flow channel 3114, sub-inlet 312, sub-outlet 313, single laminar flow channel 320, spiral section 321, annular section 322;

[0030] Co-extruded blown film 400, composite blown film layer 410, elastomer POE segment 411, PE segment 412, monomer blown film layer 420;

[0031] First axis 500. Detailed Implementation

[0032] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0033] In the description of this utility model, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0034] In the description of this utility model, "multiple" refers to two or more. The use of "first" and "second" is for distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features or their sequential relationship.

[0035] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0036] Reference Figures 1 to 6 The present invention provides a co-extrusion blown film die head suitable for cold-stretched sleeve films, comprising a die head body 100, an extrusion channel 200, and at least two laminar channels 300. An extrusion channel 200 is disposed on the die head body 100. One end of the extrusion channel 200 is provided with an annular extrusion port 210 around the first axis 500, and the other end of the extrusion channel 200 is provided with an annular inlet port 220 around the first axis 500. At least two laminar flow channels 300 are arranged radially outward along the first axis 500. Each laminar flow channel 300 is provided with an annular discharge port 301, which is connected to the annular inlet port 220. At least one laminar flow channel 300 is configured as a composite laminar flow channel 310, and the remaining laminar flow channels 300 are configured as single laminar flow channels 320. The composite laminar flow channel 310 includes at least two sub-flow channels 311. Each sub-flow channel 311 has a sub-inlet port 312 and a sub-outlet port 313. All the sub-outlets 313 located in the same composite laminar flow channel 310 are arranged around the first axis 500 and connected sequentially to form a corresponding annular discharge port 301.

[0037] One or more of the laminar flow channels 300 are composite laminar flow channels 310, and the composite laminar flow channel 310 includes two or more sub-flow channels 311. Each sub-flow channel 311 can be used for the flow of molten material of one material. The outlets of all the sub-flow channels 311 of the same composite laminar flow channel 310 are connected sequentially around the first axis 500 to form an annular discharge port 301. That is, the annular flow of material flowing out of the annular discharge port 301 can be in the form of two or more materials spliced ​​together, so that the co-extrusion blown film head 400 can produce a variety of co-extrusion blown films 400, and can flexibly combine the materials of the annular blown film layer to improve versatility, and the production cost of co-extrusion blown film 400 can be reduced.

[0038] In the embodiments, reference is made to Figure 5 A diffuser section 3111 is provided at one end of the sub-flow channel 311 near the sub-discharge port 313. The width of the diffuser section 3111 gradually increases along the direction near the sub-discharge port 313, and the end of the diffuser section 3111 forms the sub-discharge port 313. By gradually increasing the width of the sub-flow channel 311, a larger width sub-discharge port 313 is formed, which facilitates the sub-discharge ports 313 of different sub-flow channels 311 to be connected in a ring-shaped manner to form an annular discharge port 301. This allows the thickness of each sub-flow channel 311 opening to be basically the same as the thickness of the annular discharge port 301, resulting in a simple structure and relatively convenient use.

[0039] In the embodiments, reference is made to Figure 5 The diffusion section 3111 is triangular in shape, which has a simple structure, good diffusion effect, and is relatively easy to process. It is conceivable that in other embodiments, the diffusion section 3111 may also be trapezoidal or arc-shaped, etc., and those skilled in the art can choose according to actual needs.

[0040] In the embodiments, reference is made to Figure 5 The sub-channel 311 includes a direct current section 3112, which extends along the first axis 500. The end of the direct current section 3112 is connected to the beginning of the diffusion section 3111. The sub-channel 311 facilitates the feeding of the corresponding molten material into the diffusion section 3111, and has a simple structure that is easy to implement.

[0041] In the embodiments, reference is made to Figure 6 The monomer layer flow channel 320 includes a spiral section 321 and an annular section 322. One end of the spiral section 321 is a monomer inlet. The spiral section 321 is arranged around the first axis 500, and the annular section 322 is also arranged around the first axis 500. The spiral section 321 and the annular section 322 are connected, and the annular section 322 is provided with an annular outlet 301. In a conventional monomer flow channel, the molten material flows into the spiral section 321 through the monomer inlet. Subsequently, as the molten material flows along the spiral section 321, it gradually disperses into the annular section 322, which is connected to it. This results in a relatively uniform annular distribution of the molten material within the annular section 322, facilitating the subsequent entry of the molten material into the extrusion channel 200 for extrusion. The aforementioned monomer layer flow channel 320 has a relatively good dispersion effect.

[0042] In the embodiments, reference is made to Figure 3 The cross-sectional area of ​​the spiral section 321 gradually increases along the direction close to the annular discharge port 301, which facilitates the conveying of the molten material flow and has a better conveying effect.

[0043] In the embodiments, reference is made to Figure 5 The composite flow channel 310 includes four or more sub-flow channels 311. Some of the sub-flow channels 311 are configured as first sub-flow channels 3113, and the remaining sub-flow channels 311 are configured as second sub-flow channels 3114. The number of first sub-flow channels 3113 and second sub-flow channels 3114 is the same. The first sub-flow channels 3113 and second sub-flow channels 3114 are arranged alternately around the first axis 500. The first sub-flow channels 3113 and second sub-flow channels 3114 are used to transport material flows of different materials.

[0044] The aforementioned composite layer flow channel 310 has a first sub-flow channel 3113 and a second sub-flow channel 3114 arranged alternately, which allows the composite layer flow channel 310 to produce annular blown film layers with alternating splicing of two different materials, while utilizing the advantages of the two materials to produce better annular blown film layers.

[0045] It should be understood that, in some other embodiments, each sub-channel 311 of the composite layer flow channel 310 can respectively transport molten material of different materials; or be divided into a first sub-channel 3113, a second sub-channel 3114 and a third sub-channel 311, etc., to transport different materials respectively. The sub-channels 311 that transport different materials can also be arranged in any order around the first axis 500. Those skilled in the art can choose according to actual needs.

[0046] In the embodiments, reference is made to Figure 1 and Figure 2 The die head body 100 includes a distribution section 110 and an extrusion section 120. The distribution section 110 includes six die blocks 111 that are sequentially nested radially outward along a first axis 500. A laminar flow channel 300 is formed between two adjacent die blocks 111. The extrusion section 120 forms an extrusion flow channel 200 and is connected to one end of the distribution section 110. Specifically, the innermost die block 111 is cylindrical, and the remaining die blocks 111 are concentric rings. The outer wall of the die blocks 111 is machined with flow channel grooves, so that after the die blocks 111 are nested, corresponding laminar flow channels 300 can be formed between two adjacent die blocks 111.

[0047] Specifically, the distribution unit 110 includes six mold blocks 111 forming five laminar flow channels 300. It is conceivable that in other embodiments, the distribution unit 110 may also include three, four or more mold blocks 111 forming two, three or more laminar flow channels 300 respectively, and one or more of the laminar flow channels 300 may be configured as a composite laminar flow channel 310, which is not limited here.

[0048] Specifically, the extrusion section 120 of the die head body 100 has an existing structure and will not be described in detail here.

[0049] In the embodiments, reference is made to Figure 4 The laminar flow channel 300 is provided with five channels. The third laminar flow channel 300, which is radially outward along the first axis 500, is configured as a composite laminar flow channel 310, which is suitable for products in conventional production.

[0050] It is conceivable that in other implementations, any laminar flow channel 300 can be configured as a composite laminar flow channel 310, which is not limited here; the number of laminar flow channels 300 can also be two or more, which is not limited here.

[0051] Reference Figure 7The present invention also discloses a co-extrusion blown film 400, which is manufactured by the co-extrusion blown film die described above. It includes at least two stacked annular blown film layers, at least one of which is a composite blown film layer 410, and the remaining annular blown film layers are monomer blown film layers 420. The composite blown film layer 410 includes an elastomer POE segment 411 and a PE segment 412, which are arranged and connected around the central axis of the annular blown film layer.

[0052] The aforementioned co-extrusion blown film 400 can form a structure where two materials are spliced ​​together at the composite blown film layer 410. This allows for the integration of the advantages of the corresponding materials while avoiding their disadvantages, resulting in a better performance and lower cost for the co-extrusion blown film 400. Specifically, POE material is more expensive but has better elasticity, while PE material is cheaper but has poorer elasticity. When the composite blown film layer 410 uses elastomer POE segments 411 and PE segments 412 arranged and connected, the composite blown film layer 410 can have good elasticity while reducing the amount of POE material used to lower costs, and the elastic shrinkage capacity of the composite blown film layer 410 remains essentially unchanged.

[0053] In this embodiment, at least two POE segments 411 and two PE segments 412 are provided, and the number of POE segments 411 and PE segments 412 is the same. The POE segments 411 and PE segments 412 are alternately arranged and connected around the central axis of the annular blown film layer, so that the POE segments 411 can be distributed relatively evenly, thereby ensuring that the elasticity and strength of the composite blown film layer 410 are distributed relatively evenly and reducing the risk of use caused by uneven elasticity. Specifically, two, three, four or more POE segments 411 and PE segments 412 can be provided respectively, and those skilled in the art can choose according to actual needs.

[0054] In this embodiment, the annular blown film layer comprises five layers, with the third annular blown film layer being a composite blown film layer 410, and the remaining annular blown film layers being monomer blown film layers 420. The aforementioned co-extrusion blown film 400 exhibits good performance and low cost when producing cold-stretched films. Specifically, the co-extrusion blown film 400 of this embodiment includes four monomer blown film layers 420 and one composite blown film layer 410. It is conceivable that in other embodiments, the co-extrusion blown film 400 may also include two or more annular blown film layers, one or more of which are composite blown film layers 410.

[0055] It should be understood that the overall material of the blown film layer 420 can be a blend of materials with the same proportions, and it is not limited to a single material.

[0056] Understandably, color masterbatch can be added to each annular blown film layer to change its color.

[0057] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0058] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A co-extrusion blown film die suitable for cold-stretched sleeve films, characterized in that, include: Die body(100); An extrusion channel (200) is provided on the die body (100). One end of the extrusion channel (200) is provided with an annular extrusion port (210) around the first axis (500), and the other end of the extrusion channel (200) is provided with an annular inlet port (220) around the first axis (500). At least two laminar flow channels (300) are provided, each of the laminar flow channels (300) is arranged radially outward along the first axis (500), and each laminar flow channel (300) is provided with an annular discharge port (301), which is connected to the annular inlet (220). At least one of the laminar flow channels (300) is configured as a composite laminar flow channel (310), and the remaining laminar flow channels (300) are configured as single laminar flow channels (320). The composite laminar flow channel (310) includes at least two sub-flow channels (311). The sub-flow channel (311) has a sub-inlet (312) and a sub-outlet (313). All the sub-outlets (313) located in the same composite laminar flow channel (310) are arranged around the first axis (500) and connected sequentially to form the corresponding annular outlet (301).

2. The co-extrusion blown film die for cold-stretched sleeve films according to claim 1, characterized in that: A diffusion section (3111) is provided at one end of the sub-channel (311) near the sub-outlet (313). The width of the diffusion section (3111) gradually increases in the direction near the sub-outlet (313), and the end of the diffusion section (3111) forms the sub-outlet (313).

3. The co-extrusion blown film die head suitable for cold-stretched sleeve films according to claim 2, characterized in that: The diffusion section (3111) is trapezoidal or triangular.

4. The co-extrusion blown film die for cold-stretched sleeve films according to claim 1, characterized in that: The single-unit laminar flow channel (320) includes a spiral section (321) and an annular section (322). One end of the spiral section (321) is a single-unit feed inlet. The spiral section (321) is arranged around the first axis (500). The annular section (322) is arranged around the first axis (500). The spiral section (321) and the annular section (322) are connected. The annular section (322) is provided with the annular discharge port (301).

5. The co-extrusion blown film die for cold-stretched sleeve films according to claim 4, characterized in that: The cross-sectional area of ​​the spiral segment (321) gradually increases along the direction close to the annular discharge port (301).

6. The co-extrusion blown film die for cold-stretched sleeve films according to claim 1, characterized in that: The composite flow channel (310) includes at least four sub-flow channels (311), some of which are configured as first sub-flow channels (3113) and the remaining sub-flow channels (311) are configured as second sub-flow channels (3114). The number of first sub-flow channels (3113) and second sub-flow channels (3114) is the same. The first sub-flow channels (3113) and second sub-flow channels (3114) are arranged alternately around the first axis (500). The first sub-flow channels (3113) and second sub-flow channels (3114) are used to transport material flows of different materials.

7. The co-extrusion blown film die for cold-stretched sleeve films according to claim 1, characterized in that: The die head body (100) includes a distribution section (110) and an extrusion section (120). The distribution section (110) includes at least three die blocks (111) that are sequentially nested radially outward along the first axis (500). The laminar flow channel (300) is formed between two adjacent die blocks (111). The extrusion section (120) forms the extrusion flow channel (200). The extrusion section (120) is connected to one end of the distribution section (110).

8. A co-extrusion blown film, manufactured using a co-extrusion blown film die as described in any one of claims 1 to 7, characterized in that, It includes at least two stacked annular blown film layers, at least one of the annular blown film layers is a composite blown film layer (410), and the remaining annular blown film layers are monomer blown film layers (420). The composite blown film layer (410) includes an elastomer POE segment (411) and a PE segment (412), and the elastomer POE segment (411) and the PE segment (412) are arranged and connected around the central axis of the annular blown film layer.

9. The co-extruded blown film according to claim 8, characterized in that: At least two of the POE segment (411) and the PE segment (412) are provided. The number of POE segments (411) and the number of PE segments (412) are the same. The POE segments (411) and the PE segments (412) are arranged alternately and connected around the central axis of the annular blown film layer.

10. The co-extruded blown film according to claim 8, characterized in that: The annular blown film layer is provided with five layers, the third annular blown film layer is the composite blown film layer (410), and the remaining annular blown film layers are the monomer blown film layers (420).

Images