CN111844685A - Rotary die head for film formation, film formation equipment and film formation method - Google Patents

Abstract

The invention provides a rotary die head for film forming, film forming equipment and a film forming method, wherein the rotary die head for film forming comprises an annular extrusion pipeline, a feed inlet area and an extrusion outlet area which can rotate relative to the feed inlet area are sequentially arranged in a first axial direction from feeding to extrusion, and the inner wall and the outer wall of the annular extrusion pipeline in the local extrusion outlet area reversely rotate along the first axial direction; the invention improves the sealing performance of the rotary die head and avoids the leakage of resin materials.

Description

Rotary die head for film formation, film formation equipment and film formation method

Technical Field

The invention relates to the technical field of plastic film production equipment, in particular to a rotary die head for film forming, film forming equipment and a film forming method.

Background

The liquid crystal resin material (LCP) is a high-performance material with low dielectric constant and low dielectric loss, and can be used for copper clad plates in 5G antennas. Because LCP molecules have strong orientation, the LCP molecules are extremely difficult to process into films. When a common die head is used for blowing, the film has low strength in the TD direction (transverse direction) and is easy to crack. Therefore, the rotary die head is produced.

The rotary die head can improve the thickness uniformity of the film, enhance the isotropy of the film, greatly improve the product performance, and is particularly suitable for producing the film with higher requirements. FIG. 1 is a schematic diagram of a rotary die of the prior art. As shown in FIG. 1, in the prior art, a resin material in a high-temperature molten state is extruded into a feed port 101 along a device at a fixed position, and then enters a rotary die head, and is extruded into a film in a gap between an inner cylinder 102 and an outer cylinder 103 in a rotating manner. The first rotating member 104 rotates the inner cylinder 102, and the second rotating member 105 rotates the outer cylinder 103. The directions of the arrows on the first rotating member 104 and the second rotating member 105 indicate the rotating directions, respectively.

On one hand, in the prior art, the outer cylinder 103 is provided with the plurality of feed inlets 101, and resin feeding needs higher pressure, so that under the state that the outer cylinder 103 rotates at high speed, complete sealing between the inner cylinder and the outer cylinder and between the feed inlets 101 and the outer cylinder 103 is difficult to achieve, and the resin leakage is easy to occur.

On the other hand, the purpose of using a rotary die is to disturb the molecular arrangement of the material as much as possible so that the produced film has a uniform tear stress distribution in all directions. However, in the prior art, because a certain distance exists between the inner cylinder 102 and the outer cylinder 103, after the resin material enters the gap from the feed inlet 101, only the tearing stress of the material inner layer close to the inner cylinder 102 and the tearing stress of the material outer layer close to the outer cylinder 103 are uniformly distributed along all directions; the middle layer of the material is not disturbed, and the tearing stress distribution is still concentrated, so that the film is still easy to crack.

Disclosure of Invention

In view of the above, the present invention provides a rotary die head for film formation, a film forming apparatus and a film forming method, which are used to improve the sealing performance of the rotary die head and to ensure that the resin material in the gap is sufficiently disturbed so as to ensure that the tear stress of the produced film is uniformly distributed along all directions.

According to one aspect of the present invention, there is provided a rotary die for film formation, comprising:

the annular extrusion pipeline is sequentially provided with a feed inlet area and an extrusion opening area which can rotate relative to the feed inlet area in a first axial direction from feeding to extrusion, and the inner wall and the outer wall of the annular extrusion pipeline in the local extrusion opening area reversely rotate in the first axial direction.

Preferably, the rotary die comprises:

a first inner cylinder;

the first outer cylinder body is provided with a feeding hole and surrounds the first inner cylinder body;

the second rotatable inner cylinder body and the first inner cylinder body form the inner wall of the annular extrusion pipeline together;

the second rotatable outer cylinder body surrounds the second inner cylinder body, and the second outer cylinder body and the first outer cylinder body jointly form the outer wall of the annular extrusion pipeline;

the rotating direction of the second inner cylinder body is opposite to that of the second outer cylinder body.

Preferably, the rotary die head further comprises a first rotating mechanism, and the first rotating mechanism is fixedly connected with the second inner cylinder and drives the second inner cylinder to rotate.

Preferably, an air inlet joint is arranged on one side, away from the second inner cylinder, of the first rotating mechanism and used for providing an air blowing source; an air passage flow channel is formed in the inner space of the second inner cylinder, and air flowing in from the air inlet joint flows to the top of the rotary die head through the air passage flow channel.

Preferably, a stirring member is provided in the feed inlet region for changing an internal distribution state of the resin flowing through the feed inlet region.

Preferably, in the extrusion outlet area, the inner layer of the resin is driven by the rotation of the second inner cylinder to move along a first direction, and the outer layer of the resin is driven by the rotation of the second outer cylinder to move along a second direction opposite to the first direction.

Preferably, the intermediate layer of resin flows toward the top of the rotary die and forms a film.

Preferably, the outer peripheral face of barrel forms an annular arch in the first, the first end of barrel with the laminating of the outer barrel of second outside the first, the second end of barrel with the shaping of annular arch amalgamation joint outside the first, in order to realize barrel with sealing connection between the first outer barrel in the first.

Preferably, the first inner cylinder and the first outer cylinder are integrally formed.

Preferably, the second inner cylinder body is provided with an edge extending outwards along the radial direction, the edge is attached to the first end portion of the first inner cylinder body, and an outward-expanding chamfer is arranged on the inner side of the edge.

Preferably, the rotary die head further comprises a second rotating mechanism, and the second rotating mechanism drives the second outer cylinder body to rotate through meshing transmission with the second outer cylinder body.

Preferably, the surfaces of the inner wall and the outer wall of the annular extrusion pipeline in the extrusion port area are provided with a plurality of point-shaped protrusions for changing the internal distribution state of the resin flowing through the extrusion port area.

According to another aspect of the present invention, there is also provided a film-forming apparatus comprising the above-described rotary die for film formation.

According to another aspect of the present invention, there is also provided a film forming method for producing a thin film using the above film forming apparatus, the method comprising the steps of: and resin in a molten state enters the annular extrusion pipeline from the feed inlet on the first outer cylinder body, and is driven by reverse rotation in the extrusion outlet area to be extruded into a film.

Compared with the prior art, the invention has the beneficial effects that:

the rotary die head, the film forming equipment and the film forming method for forming the film keep the first inner cylinder and the first outer cylinder fixed and not rotated, resin materials enter from the feeding hole in the first outer cylinder, and the second inner cylinder and the second outer cylinder rotate in opposite directions, so that the original structure that the inner cylinder and the outer cylinder rotate is replaced, the sealing performance of the rotary die head is improved, and the leakage of the resin materials is avoided.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention. It is obvious that the drawings in the following description are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

FIG. 1 is a schematic structural view of a rotary die for film formation in the prior art;

FIG. 2 is a schematic structural diagram of a rotary die for film formation according to an embodiment of the present invention;

fig. 3 is a schematic partial cross-sectional view of a rotary die for film formation according to an embodiment of the present invention.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the disclosure. One skilled in the relevant art will recognize, however, that the subject matter of the present disclosure can be practiced without one or more of the specific details, or with other methods, materials, devices, etc. In other instances, well-known technical solutions have not been shown or described in detail to avoid obscuring aspects of the present disclosure. The same reference numerals in the drawings denote the same or similar structures, and thus their detailed description will be omitted.

The terms "a," "an," "the," "said," and "at least one" are used to indicate the presence of one or more elements/components/parts/etc.; the terms "comprising," "having," and "providing" are intended to be inclusive and mean that there may be additional elements/components/etc. other than the listed elements/components/etc.

As shown in fig. 2 and 3, the embodiment of the present invention discloses a rotary die for film formation. The direction of the arrows in fig. 2 is the resin flow direction. The rotary die has an annular extrusion line 201, and the annular extrusion line 201 is provided with a feed inlet area 202 and an extrusion outlet area 203 which can rotate relative to the feed inlet area 202 in sequence along a first axial direction of feeding to extrusion. The inner wall and the outer wall of the annular extrusion pipe 201 located in the extrusion port region 203 are rotated in the first axial direction in opposite directions.

In this embodiment, the rotary die head includes a first inner cylinder 301, a first outer cylinder 302, a second rotatable inner cylinder 303, and a second rotatable outer cylinder 304.

It should be noted that the annular extrusion line 201 is not a solid component in the present application, and is an annular channel defined by the inner and outer walls of the first inner cylinder 301, the first outer cylinder 302, the second inner cylinder 303, and the second outer cylinder 304.

In the film production process, the resin material in a molten state enters the rotary die head from the feed inlet 204 on the first outer cylinder 302, then flows from the feed inlet area 202 to the extrusion outlet area 203, and is extruded into a film from the top of the rotary die head in the extrusion outlet area 203 by utilizing the reverse rotation relationship between the feed inlet area 202 and the extrusion outlet area 203.

In this embodiment, the resin material enters from the feed inlet area 202, and the feed inlet area 202 does not need to rotate, so that the resin material is prevented from leaking after entering the feed inlet area 202, and the sealing performance of the rotary die head is improved. It should be noted that the parameters such as the arrangement, the size and the proportion, the mutual connection mode, and the like of the first inner cylinder 301, the first outer cylinder 302, the second inner cylinder 303, and the second outer cylinder 304 shown in fig. 2 do not represent the relevant parameters in the actual structure.

Referring to fig. 3, the first outer cylinder 302 is disposed around the first inner cylinder 301, that is, the first outer cylinder 302 is located radially outside the first inner cylinder 301. The second inner cylinder 303 and the first inner cylinder 301 together form the inner wall of the annular extrusion line 201. The second outer cylinder 304 is disposed around the second inner cylinder 303. The second outer cylinder 304 and the first outer cylinder 302 together form an outer wall of the annular extrusion line 201. The rotation direction of the second inner cylinder 303 is opposite to the rotation direction of the second outer cylinder 304. The first outer cylinder 302 and the second outer cylinder 304 are partially contacted and jointed, and the first inner cylinder 301 and the second inner cylinder 303 are partially contacted and jointed.

Specifically, the outer wall of the second inner cylinder 303 and the outer wall of the first inner cylinder 301 together form the inner wall of the annular extrusion pipe 201, and the inner wall of the second outer cylinder 304 and the inner wall of the first outer cylinder 302 together form the outer wall of the annular extrusion pipe 201. The first outer cylinder 302 is provided with at least one feed inlet 204, that is, one feed inlet 204 may be provided, or a plurality of feed inlets may be provided.

In this embodiment, the feed inlet area 202 is an annular channel formed by the inner wall of the first outer cylinder 302 and the outer wall of the first inner cylinder 301. The extrusion opening area 203 is an annular channel formed by the inner wall of the second outer cylinder 304 and the outer wall of the second inner cylinder 303. The present application is not limited thereto.

The rotary die head further comprises a first rotating mechanism, the second inner cylinder 303 can be fixedly connected with the first rotating mechanism at the bottom through a transmission shaft, and the first rotating mechanism is used for driving the second inner cylinder 303 to rotate. In this embodiment, the first rotating mechanism includes a first rotating member 305 and a second rotating member 306, and the first rotating member 305 and the second rotating member 306 are in meshing transmission. Wherein, the second inner cylinder 303 can be connected with the first rotating member 305 through a transmission shaft.

In other embodiments, the inner wall of the second inner cylinder 303 extends downward directly and is connected and fixed with the first rotating member 305 directly to form the inner wall of the annular extrusion pipeline 201.

In this embodiment, an air inlet joint 309 is disposed on a side of the first rotating mechanism facing away from the second inner cylinder 303, and is used for providing an air blowing source. The inner space of the second inner cylinder 303 or the transmission shaft forms an air passage. The gas flowing in from the gas inlet joint 309 flows to the top of the rotary die head through the gas path flow channel, and is blown out from the top of the second inner cylinder 303 or the transmission shaft along the circumferential direction, so that the extruded resin material is formed into a film.

Therefore, in the film forming process, the first outer cylinder 302 and the first inner cylinder 301 are fixed and do not rotate, the second outer cylinder 304 and the second inner cylinder 303 rotate oppositely, the resin material enters from the feed inlet 204 on the first outer cylinder 302 and flows upwards to the extrusion outlet area 203 between the second outer cylinder 304 and the second inner cylinder 303 along the axial direction, the possibility of resin material leakage is avoided, and the sealing performance of the rotary die head is improved. The material leakage structure caused by the material entering from the feed port 204 on the rotating first outer cylinder 302 in the prior art is replaced.

In addition, the rotary die head provided by the application can be used for designing various mechanisms of the second outer cylinder body 304 or the second inner cylinder body 303 according to actual needs, and only the second outer cylinder body 304 or the second inner cylinder body 303 needs to be replaced aiming at different products. The manufacturing difficulty and the manufacturing cost of the rotary die head can be reduced, the replacement is convenient, and the product adaptability is strong.

In this embodiment, a stirring member is provided in the inlet port region 202 to change the internal distribution of the resin flowing through the inlet port region 202. That is, the stirring member is used to make the resin material flowing through the feed inlet region 202 be sufficiently disturbed, so that the internal molecular arrangement, especially the resin material in the middle layer, is sufficiently disturbed, and thus the tear stress of the finally formed film 308 along all directions can be uniformly distributed, and the film 308 can be ensured to have sufficient tear strength along all directions.

In this embodiment, in the extrusion opening region 203, the inner layer of the resin is driven by the rotation of the second inner cylinder 303 to move along the first direction. The outer layer of resin is moved in a second direction opposite to the first direction by the rotation of the second outer cylinder 304. The intermediate layer of resin flows in the direction of the top of the rotary die, i.e., is extruded to form a film 308. The first direction is the same as the rotation direction of the second inner cylinder 303, and the second direction is the same as the rotation direction of the second outer cylinder 304.

In this embodiment, an annular protrusion is formed on the outer circumferential surface of the first inner cylinder 301, the first end of the first outer cylinder 302 is attached to the second outer cylinder 304, and the second end of the first outer cylinder 302 is formed by engaging and snapping the annular protrusion, so as to achieve the sealing connection between the first inner cylinder 301 and the first outer cylinder 302, thereby improving the sealing performance of the rotary die head. In other embodiments, the first inner cylinder 301 and the first outer cylinder 302 may be integrally formed, so as to ensure good sealing performance of the rotary die head. Or, the contact position of the first outer cylinder 302 and the first inner cylinder 301, the contact position of the first outer cylinder 302 and the second outer cylinder 304, or the contact position of the second inner cylinder 303 and the first inner cylinder 301 can be spliced by setting the contact positions to be step-shaped or convex, so that the sealing performance of the annular extrusion pipeline is improved, and the leakage of resin materials is avoided.

In another embodiment of the present application, the second inner cylinder 303 has an edge extending outward in a radial direction, the edge is attached to the first end of the first inner cylinder 301, and an outward-extending chamfer is disposed on an inner side of the edge, so that the gas in the gas path channel can be blown to the films 308 on both sides at a preferred angle, which is beneficial to better molding the films 308.

In another embodiment of the present application, on the basis of the above embodiment, the rotary die head further includes a second rotating mechanism 307, and the second rotating mechanism 307 drives the second outer cylinder 304 to rotate through meshing transmission with the second outer cylinder 304. Thus, the first outer cylinder 302 does not need to rotate, which is beneficial to improving the sealing performance of the first outer cylinder 302, namely the rotary die.

In another embodiment of the present application, a plurality of dot-shaped protrusions are disposed on the inner wall and the outer wall of the annular extrusion pipe 201, i.e. the inner wall of the second outer cylinder 304 and the outer wall of the second inner cylinder 303, in the extrusion port region 203, for changing the internal distribution state of the resin flowing through the extrusion port region 203. This is favorable to further disordering the resin material in the annular extrusion pipeline 201, is favorable to further disordering the molecular orientation in the resin, and is also favorable to making the tearing stress distribution of the film 308 along all directions uniform.

Embodiments of the present invention further provide a film forming apparatus, where the film forming apparatus includes the rotary die for film formation disclosed in the above embodiments, and detailed structural features and advantages of the rotary die may refer to the description of the above embodiments, and are not described herein again.

The embodiment of the invention also provides a film forming method, which applies the film forming equipment disclosed by the embodiment to produce a film, and comprises the following steps: and (3) enabling the resin in a molten state to enter the annular extrusion pipeline from the feeding hole on the first outer barrel, enabling the resin to axially flow upwards to the extrusion port area in the feeding hole area of the annular extrusion pipeline, and extruding the resin into a film under the driving of reverse rotation in the extrusion port area.

Wherein, the inner layer of the resin material in the extrusion outlet area is driven by the rotation of the second inner cylinder body to move along the first direction. The outer layer of the resin is driven by the rotation of the second outer cylinder to move along a second direction opposite to the first direction. The intermediate layer of resin flows in the direction of the top of the rotary die, i.e., is extruded into a film. The first direction is the same as the rotation direction of the second inner cylinder, and the second direction is the same as the rotation direction of the second outer cylinder.

In summary, the rotary die head, the film forming apparatus and the film forming method for film formation disclosed by the present invention have at least the following advantages:

the rotary die head, the film forming equipment and the film forming method for film forming disclosed by the embodiment keep the first inner cylinder and the first outer cylinder fixed and not rotated, resin materials enter from the feeding hole in the first outer cylinder, and the second inner cylinder and the second outer cylinder rotate in opposite directions, so that the original structure that the inner cylinder and the outer cylinder rotate is replaced, the sealing performance of the rotary die head is improved, and the leakage of the resin materials is avoided; meanwhile, the stirring piece is arranged in the feed inlet area, so that the molecular arrangement in the material is sufficiently disturbed, the produced film is ensured to be uniformly distributed along the tearing stress of all directions, and the strength of the film along all directions is improved.

In the description of the present invention, it is to be understood that the terms "bottom", "longitudinal", "lateral", "upper", "lower", "front", "rear", "vertical", "horizontal", and the like, indicate orientations and positional relationships based on the orientations and positional relationships shown in the drawings, are used only for convenience in describing the present invention and for simplification of description, and do not indicate or imply that the structures or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, are not to be construed as limiting the present invention. Furthermore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more and "several" means one or more unless otherwise specified.

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

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.

Claims (14)

1. A rotary die for forming a film, comprising:

the annular extrusion pipeline (201) is sequentially provided with a feed port area (202) and an extrusion port area (203) which can rotate relative to the feed port area (202) along a first axial direction of feeding to extrusion, and the inner wall and the outer wall of the annular extrusion pipeline (201) in a part of the extrusion port area (203) rotate reversely along the first axial direction.

2. The rotary die for film formation according to claim 1, comprising:

a first inner cylinder (301);

a first outer cylinder (302) with a feed inlet (204) surrounding the first inner cylinder (301);

the second rotatable inner cylinder (303) and the first inner cylinder (301) form the inner wall of the annular extrusion pipeline (201) together;

a second rotatable outer cylinder (304) surrounding the second inner cylinder (303), the second outer cylinder (304) and the first outer cylinder (302) together forming an outer wall of the annular extrusion pipeline (201);

the second inner cylinder (303) rotates in the opposite direction to the second outer cylinder (304).

3. The rotary die head for forming a film according to claim 2, further comprising a first rotating mechanism which is fixedly connected to the second inner cylinder (303) and drives the second inner cylinder (303) to rotate.

4. The rotary die head for film formation according to claim 3, wherein a side of the first rotary mechanism facing away from the second inner cylinder (303) is provided with an air inlet joint (309) for providing an air blowing source; an air passage flow channel is formed in the inner space of the second inner cylinder (303), and air flowing in from the air inlet joint (309) flows to the top of the rotary die head through the air passage flow channel.

5. The rotary die for film formation according to claim 2, wherein a stirring member is provided in said feed port region (202) for changing the internal distribution state of the resin flowing through said feed port region (202).

6. The rotary die for film formation according to claim 2, wherein in the extrusion port region (203), the inner layer of resin is moved in a first direction by the rotation of the second inner cylinder (303), and the outer layer of resin is moved in a second direction opposite to the first direction by the rotation of the second outer cylinder (304).

7. The rotary die for film formation according to claim 6, wherein the intermediate layer of the resin flows toward the top of the rotary die and forms a film.

8. The rotary die head for forming a film according to claim 2, wherein an annular protrusion is formed on the outer peripheral surface of the first inner cylinder (301), the first end of the first outer cylinder (302) is attached to the second outer cylinder (304), and the second end of the first outer cylinder (302) is formed by splicing and clamping the annular protrusion, so as to realize the sealing connection between the first inner cylinder (301) and the first outer cylinder (302).

9. The rotary die for film formation according to claim 2, wherein the first inner cylinder (301) is integrally formed with the first outer cylinder (302).

10. The rotary die for forming a film according to claim 2, wherein the second inner cylinder (303) has a radially outwardly extending rim which abuts the first end of the first inner cylinder (301), and the inside of the rim is provided with an outward-extending chamfer.

11. The rotary die for forming a film according to claim 2, further comprising a second rotating mechanism (307), wherein the second rotating mechanism (307) rotates the second outer cylinder (304) by meshing transmission with the second outer cylinder (304).

12. The rotary die for film formation according to claim 2, wherein the surfaces of the inner wall and the outer wall of the annular extrusion line (201) located in the extrusion port region (203) are each provided with a plurality of dot-like projections for changing the internal distribution state of the resin flowing through the extrusion port region (203).

13. A film-forming apparatus comprising the rotary die for film formation according to any one of claims 2 to 12.

14. A film forming method for producing a thin film by using the film forming apparatus according to claim 13, the method comprising the steps of: and resin in a molten state enters the annular extrusion pipeline from the feed inlet on the first outer cylinder body, and is driven by reverse rotation in the extrusion outlet area to be extruded into a film.

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