JPH1029237A - Spiral die and manufacture of laminate by using the die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the formation of multilayered laminates, the number of laminations of which are different from one another, from the combination of a plurality of resins by a method wherein a plurality of spiral flow path grooves, the depth of each of which gradually becomes shallower, are formed on an inside die ring side between an inside die ring and an outside die ring. SOLUTION: When the distances between the starting points of spiral flow path grooves 24a and 24b and the arriving position on an inner surface under the condition that an inside die ring 122a is rotated to positive direction become longer than those under the condition that the inside die ring 122a stands still, a development angle (ω) becomes larger. When the distances under the condition that the inside die ring 122a is rotated to negative direction become shorter, resulting in becoming the development angle (ω) smaller. Thus, by changing the rotational direction of the inside die ring 122a, the development angle (ω) of the leaking resin can be increased or decreased, resulting in allowing to increase or decrease the number of laminations to the direction of the thickness of a film at the specified planar position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spiral die for extruding a laminated resin cylindrical body and a method for producing a laminated body using the same.

[0002]

2. Description of the Related Art In order to obtain characteristics that cannot be obtained with a single resin film, it is widely practiced to form a laminated resin film. As a typical example of such a laminated resin film, a gas barrier resin layer that is difficult to stretch by itself and an adhesive layer that imparts stretchability to the gas barrier resin layer and adheres to the gas barrier resin layer And a laminated film of a resin layer having good properties. A preferred method for producing such a laminated resin film is a multilayer inflation method. The performance of the laminated resin film is particularly affected by the number of laminations, and as long as they have the same composition ratio, the larger the number of laminations, the smaller the Young's modulus. It is desired to increase the number of layers for the purpose of controlling the physical properties of the obtained laminated resin film,
The number of laminated resin films obtained by the conventional method is generally about 10 at the maximum, and is not realized due to an increase in the size of the die due to an increase in the number of resin flow paths in the die described later.

[0003] Generally, each resin to be laminated is melt-kneaded by an individual extruder and then supplied to a molding die used in a multilayer inflation method through respective pipe-shaped flow paths.

[0004] In addition to basic types such as a spider type, a spiral type, a crosshead type, and a manifold type, there are molding dies of a combination of these types. Regardless of the method, in the die, each resin is molded into a thin-walled cylindrical shape by itself according to the respective flow path method, and after the wall thickness is adjusted, it is similarly molded into a thin-walled cylindrical shape. And merges with the other flowing cylindrical resin flow, and is laminated to form a multilayer tube, which is extruded from the die lip. In such a die, a cylindrical resin flow path corresponding to the required number of laminations is required, and when the number of laminations is increased to improve the function of the laminated inflation film, the die becomes correspondingly complicated and large in size. It is evident that the fabrication and assembly of the die is complicated, the die requires a great deal of cost, and there are many problems in the work of assembling and disassembling the die.

Some proposals have been made to obtain a laminate with a simpler die structure. For example, Japanese Patent Publication No. 55-23733 proposes a method in which another molten resin is supplied from the inside to the middle of the flow path of the spiral die to obtain a laminate. Also, Japanese Patent Application Laid-Open No. Hei 1-261426 proposes a method in which an auxiliary thermoplastic resin is passed through a so-called static mixer into a base thermoplastic resin to be dispersed in a film form. However, these methods are still not satisfactory from the viewpoint of obtaining a multilayer laminate using a simpler resin flow path or maintaining a laminating effect.

On the other hand, in the production of a multilayer blown film, a spiral die is commonly used. However, since a molten resin is molded into a thin cylindrical shape having a small thickness unevenness, the number of spiral die (the number of spiral flow grooves) is increased. It is desirable to increase as much as possible. In order to uniformly distribute the molten resin in such multi-slotted grooves, a method of uniformly distributing the molten resin supplied from the side direction by the (reverse) tournament-shaped branch grooves provided on the peripheral surface of the die ring. (JP-B-58-29209). However, the (reverse) tournament branching method is a method for achieving uniform distribution of a single (single) molten resin.

As a result of a study in consideration of the above circumstances, the present inventors have conducted a study for a spiral die having a simple structure capable of efficiently manufacturing a multilayer laminate of a plurality of resins. Using the (reverse) tournament method branching method, which has been used for the uniform distribution of a single molten resin, for distributing a plurality of resins in a certain order, the distributed plural resins are formed into multi-strand spiral flow grooves. It has been found that by introducing the same, a laminate in which the plurality of resins are regularly laminated can be effectively obtained, and a spiral die for molding a laminate having a simple structure has already been developed. That is, the spiral die for forming a laminate has a plurality (m; where m is a natural number) of spirals each having a gradually decreasing depth between an inner die ring and an outer die ring arranged in a fitting relationship with each other. A plurality of (m) spiral flow grooves are formed in the plurality of (m) spiral flow grooves, where n is a natural number and n <m.
A distribution groove for distributing and introducing a molten resin flow composed of different resins in a certain order is provided, and before each resin flow proceeds in a spiral flow path groove to form a uniform cylindrical flow in the die axis direction. Further, the plurality of molten resin flows are laminated in a certain order as a leakage flow from the spiral flow passage groove (Japanese Patent Laid-Open No. 8-903).
No. 62).

[0008]

The spiral die (fixed spiral die) for forming a laminate developed as described above is extremely effective in that a multilayer laminate can be formed with a simple structure. In addition, it was possible to some extent to increase or decrease the number of laminations affecting the properties of the product film or sheet in a narrow range such as the melt viscosity of the inflow resin and the melt viscosity ratio. However, if you want to change the number of laminations even more, you need to change the design of the spiral flow channel and prepare a separate spiral die. Was impossible to control.

Accordingly, a main object of the present invention is to provide a spiral die capable of forming a multilayer laminate having a different number of laminates from a combination of a plurality of resins, and a method of manufacturing a laminate using the spiral die.

[0010]

Means for Solving the Problems As a result of further research for the above-mentioned objects, the present inventors have found that the spiral die (fixed spiral die) for forming a laminated body, which has been developed earlier, has an inner die ring and an outer die ring. By changing the configuration to rotate at least one of them and adjusting the rotation direction and speed or the rotating part, the design of the spiral flow channel using the same combination of multiple resins used when using the fixed spiral die, etc. Found that even when extrusion molding was performed from the same spiral die as the fixed spiral die, a laminate having a different number of layers could be formed.

The spiral die (rotating spiral die) for forming a laminate according to the present invention is based on such knowledge. More specifically, the inner die and the outer die are fitted to each other in a fitting relationship, and At least one of them is rotatably arranged, and a plurality of spirals (m; m is a natural number) of decreasing depth are provided on the inner die side between the inner die and the outer die. A flow channel is formed, and a plurality of (n; n is a natural number and n <m) molten resin flows composed of different resins are arranged in a predetermined order in the plurality (m) of spiral flow channels. A distribution groove for distributing and introducing is provided, and before the individual resin flows supplied from the inner die ring through the distribution groove advance in the spiral flow channel to form a uniform cylindrical flow in the die axis direction, It is characterized in that the number of the molten resin flow is configured to be stacked in a certain order as a leakage flow from the spiral flow path groove.

According to another aspect of the present invention, the inner die ring and the outer die ring are arranged in a fitting relationship with each other, and at least one of them is rotatably arranged.
A spiral die formed by forming a plurality (m; m is a natural number) of spiral flow grooves gradually decreasing in depth on the inner die side between the inner die ring and the outer die ring; While rotating at least one of the die rings, a plurality of (n; n is a natural number and n <m) different resins are formed in the plurality of (m) spiral flow grooves while rotating at least one of the die rings. Before the molten resin flow is distributed and introduced in a certain order through the distribution grooves provided in the inner die ring, the individual resin flows advance in the spiral flow channel to form a uniform cylindrical flow in the die axial direction. By laminating the plurality of molten resin flows in the fixed order as a leakage flow from the spiral flow channel, a laminated tubular body in which the plurality of resins are obliquely laminated in a circumferential cross section can be obtained. Laminate manufacturing method according to claim is provided.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below mainly based on comparative examples and examples in which a laminated tubular body of a gas barrier resin A and a resin B having excellent stretchability and adhesiveness is obtained. Will be explained.

FIG. 1A is a schematic sectional view of a conventional general spiral die for multilayer molding. First, a spiral die 11 is extruded from an extruder 10a (not shown).
The resin B introduced into the inside is uniformly branched by a so-called (reverse) tournament type branch path 13a (a plurality is provided, but only one is shown) arranged near the outer periphery of the first die ring (innermost ring) 12a. Are introduced into a plurality of spiral flow grooves 14a provided on the outer peripheral surface of the first die ring 12a. Each of the spiral flow channel grooves 14a has a groove depth that becomes gradually smaller as it proceeds in the traveling direction (upward), and the flow of the molten resin B passing therethrough is
b, spirally upward while forming a leakage flow overflowing the groove in the gap with b, and finally advance upward as a uniform axial cylindrical flow in the cylindrical flow path 15a having no groove. It reaches 16.
On the other hand, the flow of the molten resin A extruded from the extruder 10b is similarly branched, and flows through a spiral flow accompanied by a leakage flow to form the cylindrical flow path 1.
A homogeneous axial cylindrical flow passing through 5b is reached and reaches a junction 16. Similarly, the flow of the molten resin B extruded by the extruder 10c also passes through a spiral flow accompanied by a branching and a leaking flow, and becomes a uniform axial cylindrical flow passing through the cylindrical flow path 15c.
To 6. At the junction 16, these three cylindrical flows are laminated and extruded from the die lip 17 as a laminated cylindrical body. As shown in FIG. 1 (b), the laminated tubular body extruded from the die lip 17 has an adhesive and extensible resin layer B on both sides with a gas barrier resin layer A as an intermediate layer.
Constitute a cylindrical laminate.

The thus obtained tubular laminate is subjected to an inflation process for expanding the circumference and reducing the thickness as necessary, and then a sheet or sheet obtained by cutting in a direction generally parallel to the axis. Film (hereinafter, generically referred to as "film" without intention of limiting thickness)
FIG. 2 ((a) is a schematic perspective view, (b) is a vertical (MD) direction sectional view parallel to the axis, (c) is a TD direction (direction orthogonal to MD) sectional view), Resin A layer has two resins B
The resulting film has a uniform three-layer structure.

On the other hand, FIG. 3A is a schematic sectional view of a fixed spiral die 21 previously developed by the present inventors, which is extruded from extruders 20a and 20b and introduced into the spiral die 21 respectively. Molten resin A and B
Is branched by a tournament type branch (not shown, described later) similar to 13a in FIG. 1A, and then a plurality of spiral flow grooves 24a are formed. , 24b. Then, as a spiral flow accompanied by a leakage flow along these spiral flow grooves, the molten resin A and the molten resin A are formed in a process of moving upward through a single cylindrical flow path between the inner die ring 22a and the outer die ring 22b. B are alternately stacked obliquely and extruded from the die lip 27 through the cylindrical flow path 25 having no spiral flow path groove. As shown in FIG. 3 (b), the extruded laminated tubular body has a circumferential section (cross section perpendicular to the axis (TD) direction) in which resins A and B are alternately laminated obliquely. Become.

FIG. 4 is a schematic perspective view of a frame III portion surrounded by a dashed line in FIG. 3 (a) for explaining the distribution-stacking of the molten resin flows A and B in more detail. That is, the molten resin flows A and B introduced into the spiral die 21 through the extruders 20a and 20b first reach the tournament branch points 23a1 and 23b1, and further branch therefrom through the branch points 23a2, 23b2. After repeating the final branch points 23a3 and 23b3, the distribution section final flow paths 28a, 28b, 28a, 28b
.. from which the spiral flow channel 24a,
The resin flows A and B alternately flow into 24b, 24a, 24b. Here, the spiral flow grooves 24a, 24
, 24a, 24b... (distribution section final flow path 2
8a, 28b, 28a, 28b,...) Are located substantially on the same circumferential line of the inner die ring 22a. At first, the resin flows A and B entering the spiral flow grooves 24a and 24b initially exclusively use the spiral flow grooves 24a and 24b.
a, a spiral flow along 24b, but gradually the inner die ring 22a, especially its spiral peak 22aa
22ab which is a gap between the outer die ring 22b and the outer die ring 22b
A leakage flow over the spiral peak 22aa occurs along the flow path (ie, upward). That is, the flow films of the resin A and the resin B flow out of the spiral flow grooves as if formed in the circumferential direction. Then, the flow films of the resin A and the resin B thus formed are respectively formed on the flow film of the resin B and the resin A flowing out of the spiral grooves 24b and 24a on the downstream side, that is, the flow film A and the flow film B are respectively formed. The layers are stacked alternately. The lamination angle is the development angle ω of the resin leaking from each spiral channel groove (see FIG. 3).
(B)). That is, the starting point of the spiral flow channel forms the outer surface side, moves toward the inner surface side as the layers are stacked, and reaches the inner surface when moved by the development angle ω. As described above, the resin A and the resin B are stacked in an inclined state by the respective development angles ω (FIG. 3B). The development angle ω can be controlled by the initial depth of the spiral flow grooves 24a and 24b formed for each of the resins A and B, the rate of gradually decreasing the depth, and the like.
It is in the range of 60 ° to 720 °, preferably in the range of 80 ° to 360 °, more preferably in the range of 130 ° to 230 °.

Returning to FIG. 3, the laminated cylindrical body extruded from the die lip is subjected to an inflation process for enlarging and thinning as necessary, and is generally cut in a direction parallel to the axis to obtain a film. The shape is

The laminated resin films thus obtained are shown in FIGS. 5 (a) to 5 (c) corresponding to FIGS. 2 (a) to 2 (c).
It has a structure as shown in FIG. In particular, FIG.
As is clear from (c), the laminated resin film 1
The cross section in the D direction shows a mode in which the resin layers A and B are alternately stacked in parallel (FIG. 5 (b)), but in the cross section in the TD direction, each of the resin layers A and B has two main surfaces 1a. , 1b are alternately stacked diagonally so as to reach (FIG. 5
(C)). However, the angle θ formed by the individual resin layers A and B with the two main surfaces 1a and 1b of the laminated resin film 1 is as shown in FIG.
It is not large enough to be expressed in (c) and generally ranges from more than 0 ° to 4 °, especially from 0.001 ° to 0.4 °. The angle θ can be represented by the following relational expression.

Tan θ = [film thickness (mm)] /
[Length of film circumference (mm) x development angle (ω) / 360
゜] As can be seen from the above description, the fixed spiral die described with reference to FIGS. 3 and 4 developed earlier by the present inventors has, for example, two types of resins A and B while having a simple structure. The combination has an extremely characteristic effect that a multilayer laminate having a lamination number of 10 to 20 is easily formed. However, as mentioned earlier, the number of layers
A specific spiral die is governed by a combination of resins, and it is difficult to increase or decrease the spiral die to some extent, and basically requires a design change of the spiral die. On the other hand, the rotating spiral die of the present invention has a structure in which at least one of the inner die ring and the outer die ring is rotatable, and changes in operating conditions such as changing the rotation speed, the rotation direction, the rotation part, etc. This makes it possible to relatively easily change the number of laminations relatively easily. Less than,
The embodiment will be further described with reference to the drawings.

FIGS. 6 to 10 show a preferred embodiment of the rotary spiral die 121 of the present invention, in which the inner die ring is rotatable and the outer die ring is fixed (non-rotating). FIG. 6 is an overall explanatory view including a driving system; FIG. 7 is an enlarged view of an inner die ring (spiral mandrel portion) 122a in a portion surrounded by a dotted line X in FIG. FIG. 9 is a view showing a state in which the covers of the distribution grooves provided in the distribution section are further removed one by one. FIG. 10 is a sectional view including the axis of the rotary spiral die 121 formed by combining the inner die ring 122a and the outer die ring 122b. In FIG. 6 and subsequent figures, parts similar to those in FIGS. 6 to 9, the spiral die 121 is used.
Are shown wider than FIG. 10 for convenience of description, but the actual vertical / horizontal dimension ratio is closer in FIG.

As compared with the fixed spiral die 21 described with reference to FIGS. 3 and 4, the rotary spiral die 121 has a sprocket 3 provided below the inner die ring 122a.
1 (FIG. 10) around the chain 32 and the motor 33
In that the inner die 22a is rotatable.

The flows of the resins A and B introduced into the rotary spiral die 121 by the extruders 20a and 20b basically change the flow of the resin A introduced into the fixed spiral die 21 described with reference to FIGS. And B. FIG. 8 is mainly a flow path structure of the resin A in the distribution section, that is, branch points 23a1, 23a2,.
FIG. 9 shows the flow path 28a, and FIG. 9 shows the resin B provided inside except for a layer corresponding to the flow path of the resin A from FIG.
, That is, the branch portions 23b1, 23b2,.
-The flow path 28b is shown. However, the resin A flow path structure shown in FIG. 8 further rotates integrally with the inner die ring 122a, and is covered with a cover 34 that provides a rotational sliding surface with the outer die ring 122b. 28a is configured to be exposed on the sliding surface with the outer die ring 122b so that the distribution of the resin A (and the regular lamination with the resin B layer) is not hindered. The rotation of the inner die ring 122 a with respect to the shaft portion 37 is supported by the bearing 35.

In accordance with the present invention, the inner die ring 122a
Is rotated with respect to the fixed outer die ring 122b, by changing the rotation direction and the rotation speed, the development angle ω of the resin leaking from each spiral flow channel 24a, 24b (FIG. 6 (b)). Changes. That is, the inner die ring 122a is moved in the forward direction (the spiral flow channel 24
a and 24b are rotated in the direction in which the screws are loosened (similar to screws), and if the distance between the starting point of the spiral flow channel and the inner surface reaching position is longer than when the inner die ring 122a is stationary, the expansion is performed. When the angle ω increases and the distance becomes shorter by rotating in the negative direction, the development angle ω decreases. With such a mechanism, it is possible to increase or decrease the development angle of the leaking resin by changing the rotation direction of the inner die ring 122a, and as a result, the number of layers in the thickness direction of the film at a specific plane position Can be increased or decreased. The degree of the increase / decrease can be increased by increasing the rotation speed of the inner die ring 122a.

As described above, the rotary spiral die 12
When the laminated tubular body extruded from the first die lip 27 (FIG. 4) is torn in a direction parallel to the axis similarly to the case of the fixed spiral die 21 in FIG. 3, it corresponds to FIGS. 5 (a) to 5 (c). Thus, a laminated film having a structure as shown in FIGS. 11 (a) to 11 (c) is obtained. In the cross section in the MD direction (FIG. 5B), the laminated film shown in FIGS. 5B and 5C shows a layer arrangement in which the resin A layer and the resin B layer are almost parallel to the main surface, Only the cross section in the TD direction (FIG. 5 (c)) shows an inclination, whereas the cross section in the MD direction (FIG.
1 (b)) and the cross section in the TD direction (FIG. 11 (c)) are characteristically inclined at inclination angles θ ₁ and θ ₂ . Generally, the inclination angle is in the range of about 0 ° <θ ₁ and θ ₂ ≦ 4 °.

Another characteristic is that, for example, the designs of the spiral flow grooves 24a and 24b of the resin A and the resin B (the full width and the full depth of the spiral flow grooves) are the same. If the melt viscosity η _A of the resin B and the melt viscosity η _{B of the} resin B are η _A > η _B , as shown in FIGS. 11B and 11C, the resin A is on the inner surface side and the resin B is on the inner surface side. A dominantly arranged surface layer is formed on the outer surface. Where η _A =
In the case of η _B , as shown in FIG.
B reaches the two main surfaces, and gives a striped exposed pattern of the resins A and B on both surfaces. That is, according to the physical properties of the surface required for the obtained laminate,
It is possible to change the surface condition by changing the spiral flow path design or the melt viscosity of the flowing resin.

Each of these resins A and B (which may be a resin mixture or a single resin, respectively) has a melt viscosity at the processing temperature of 100 to 5000 Pa · s.
s, preferably 300 to 2000 Pa · s, and more preferably 400 to 1200 Pa · s.

In the case of forming an alternating diagonal laminate using the rotary spiral die of the present invention, the resin A and the resin B have a volume ratio of the resin introduced into the spiral die of 1: 0.0
The ratio is preferably 5 to 1:20, more preferably 1: 0.3 to 1: 3, and still more preferably 1: 0.6 to 1: 1.5. In addition, this volume ratio is an example in the case where spirals having substantially the same groove depth and width at the start point and end point of the spiral flow channel into which the resin A is introduced and the spiral flow channel into which the resin B is introduced are used. The volume ratio changes due to the change in the spiral channel design including these.

The resin A introduced into the spiral die
And resin B desirably have an approximate melt viscosity,
For example, when using spirals in which the depth and width of the spiral flow channel into which the mixed resin is introduced and the spiral flow channel into which the single resin is introduced are substantially equal at the start point and the end point, melting at the processing temperature is performed. When the viscosity ratio is 1:
0.5 to 1: 2.0, more preferably 1: 0.6 to 1:
It is preferably in the range of 1.5, especially 1: 0.7 to 1: 1.3. However, the optimum ratio of the melt viscosity can be changed by changing the spiral flow channel design such as the depth and width of the spiral flow channel.

On the other hand, the rotational speed of the spiral mandrel (inner die ring) 122a, which is a die rotating portion, is 0.0
5 to 100 rotations / minute, preferably 0.05 to 50
The rotation speed is more preferably 0.1 to 20 rotations / minute. When the number of rotations is less than 0.05 rotations / minute, it is difficult to increase or decrease the number of layers, and it is difficult to control the number of rotations.
If the number of rotations exceeds 100 rotations, galling (becoming stuck and not moving) on the sliding surface between the rotating part and the fixed part may occur.

The rotating direction of the spiral mandrel (inner die ring), which is the die rotating portion, may be either the positive direction or the negative direction (reverse direction) as described above, whereby the number of stacked layers can be increased or decreased.

In the spiral die of the present invention, as the rotating portion, both the inner die ring 122a and the die lip 27 may be rotated, or the inner die ring 12a may be rotated.
Only 2a may be rotated. Alternatively, only the outer die ring 122b may be rotated, or both the outer die ring 122b and the inner die ring 122a, the outer die ring 122b, the inner die ring 122a, and the die lip 2 may be rotated.
7 may be rotated. In particular, it is particularly preferable to rotate both the inner die ring 122a and the die lip 27, or only the inner die ring 122a, from the viewpoint of controlling the number of layers and miniaturizing the apparatus. The rotation speed and the rotation direction when the outer die ring is rotated may be controlled in the same manner as in the case where the inner die ring is rotated. Also, the inner die ring 122a
In order to prevent metal and metal galling on the sliding surface between the outer die ring 122b and the outer die ring 122b, the metal material used for the inner die ring and the outer die ring may have a difference in hardness,
Bearings may be provided. For the same purpose, it is also preferable to provide a resin leak port 36 (FIG. 10) so that a small amount of molten resin always leaks to the outside.

As a method for driving the die ring, FIG.
As shown in FIG.
Instead of the method of connecting and rotating the motor 33 attached to the side of the spiral die with the chain 32 and attaching the inner die ring 122a and the motor 33 as shown in FIG. Either of these may be used as needed. FIGS. 6 and 12 show only the method of rotating the inner die ring, but the present invention is not limited to this, and the outer die ring can be driven in a similar manner.

In the above, the alternate laminated structure (A / B / A / B / A / B...) Of two types of resins A and B has been described. However, the order of lamination of various resin layers is arbitrary,
For example, for two types of resins A and B, A / B / B / A / B
/ B / A ... or A / B / B / A / A / B / B /
A repeated structure such as A ... is also possible. In order to obtain a laminated resin film having uniform properties as a whole, it is preferable to repeatedly perform lamination in a certain order to obtain a laminated resin molded product. It is also possible to laminate three or more types of resins. For example, the following is an example of a lamination order for three types of resins, A, B and C.

A / B / C / A / B / C / A..., A / B / C / B / A / B / C / B / A. / B / A / B / C / A / B / A / B / C ..., A / B / C / B / A / B / C / B / A ...

When forming a laminate according to the method of the present invention,
A plurality (n; n is a natural number) of different resins, that is, the number (n) of resin types for lamination is 2 to 4, while
Plural (m; where m is a natural number and n <m)
Spiral flow channel, that is, spiral flow channel 24a,
The total number of spiral flow channels (m) including 24b and the like, in other words, the number of laminations (m) is from 4 to 256 grooves (layers), and further from 8 to
It is preferable to have about 128 grooves (layers), especially about 16 to 64 grooves (layers), and the number of layers in the thickness direction at a specific plane direction position is preferably about 4 to 1000 layers, particularly about 8 to 500 layers. The number of layers in the thickness direction is determined as m × ω / 360 from the number m of spiral flow grooves (number of spiral grooves) and the development angle ω. The overall thickness of the laminated resin molding can be controlled quite widely,
For example, a thickness of about 10 μm to 1 mm, particularly about 15 to 200 μm is preferable. Also, at least one surface of the obtained oblique laminated resin film as shown in FIGS.
In many cases, it is also preferable to further coat one or more resin layers of different types or the same type (with the constituent resin of the oblique laminated resin film).

For the purpose described above, the spiral die of the present invention is also provided with another resin flowing into the spiral die of the present invention, which forms a laminate, inside or outside or on both sides of the resin flow path. It is also possible to newly provide a resin flow path for causing this to occur. As a newly provided resin flow path,
A normal non-rotating spiral die ring or a previously developed fixed spiral die for forming a laminate may be used. Further, the rotatable spiral die ring of the present invention can be provided inside or outside the resin flow path or on both sides thereof, and a plurality of rotating die rings may be simultaneously rotated.

Hereinafter, a production example and a comparative example of a laminated resin film using a die corresponding to an example of the present invention will be described.

Example 1 As shown in FIGS. 6 (a) and 10, an oblique molded body capable of alternately flowing two kinds of resins and rotating the inner die ring 122a in both forward and reverse directions. Using a forming spiral die 121 (m = 32) (the outer die ring is fixed and non-rotating), it is co-extruded into a cylindrical shape (extrusion temperature 180 to 210).
C., a die temperature of 200 ° C.), a circumferential length of 244 mm, and a thickness of 200 μm. The extrusion temperature of each resin is shown in Table 2. At this time, the rotation speed of the inner die ring was set to 0.5 rotation / minute (rpm) in the forward direction (in the case where the spiral groove was compared to a screw, in the direction in which the screw was loosened). The structure of the obtained oblique laminate is such that a resin A is a saponified ethylene-vinyl acetate copolymer (hereinafter abbreviated as “EVOH”), and a resin B is a copolymer of nylon 6 and nylon 12 (hereinafter “Ny6-12”). ], And the thickness ratio of each is EVOH = 100 μm (total thickness), Ny6-12 =
100 μm (total thickness), the number of layers was 21 to 23. EVOH has an ethylene content of 44 mol% and a saponification degree of 9
9.4%, melt viscosity (200 ° C., 25 sec ⁻¹ ) = 90
"EVAL EPE105A" manufactured by Kuraray of 1 Pa.s was used. Ny6-12 has a melt viscosity (200 ° C., 2
5 sec ^-1 ) = Amilan CM6 manufactured by Toray of 814 Pa · s
541X3 was used. About the obtained oblique laminate,
Measure yield stress, rupture stress, rupture elongation, Young's modulus,
The results are shown in Table 1.

Example 2 An oblique laminated body was manufactured in exactly the same manner as in Example 1 except that the number of revolutions of the inner die ring 122a during the production of the oblique laminated body was set to 1 rpm in the positive direction. The number of laminations of the obtained oblique laminate was 29 to 31 layers. With respect to the obtained oblique laminate, the yield point stress, rupture stress, rupture elongation, and Young's modulus were measured, and the results are shown in Table 1.

Example 3 An oblique laminated body was manufactured in exactly the same manner as in Example 1 except that the number of rotations of the inner die ring 122a during the production of the oblique laminated body was set to 2 rpm in the positive direction. The number of layers of the obtained oblique laminate was 45 to 47 layers. With respect to the obtained oblique laminate, the yield point stress, rupture stress, rupture elongation, and Young's modulus were measured, and the results are shown in Table 1.

Example 4 Except that the rotational speed of the inner die ring during the manufacture of the oblique laminate was set to 4 rpm in the positive direction,
An oblique laminate was manufactured in exactly the same manner as in Example 1. The lamination number of the obtained oblique laminate was 55 to 57 layers. With respect to the obtained oblique laminate, the yield point stress, rupture stress, rupture elongation, and Young's modulus were measured, and the results are shown in Table 1.

Example 5 An oblique laminate was manufactured in exactly the same manner as in Example 1 except that the rotational speed of the inner die ring during the manufacture of the oblique laminate was set to 0.1 rpm in the reverse direction. The number of layers of the obtained oblique laminate was 10 to 11 layers. With respect to the obtained oblique laminate, the yield point stress, rupture stress, rupture elongation, and Young's modulus were measured, and the results are shown in Table 1.

(Comparative Example 1) As shown in FIGS.
An oblique laminated body was manufactured in the same manner as in Example 1 except that a spiral die for forming an oblique molded body (m = 32, the inner die ring 22a of which cannot be rotated) capable of alternately inflow-working kinds of resins was used. . The number of laminations of the obtained oblique laminate was 14 to 15 layers. About the obtained oblique laminate,
Measure yield stress, rupture stress, rupture elongation, Young's modulus,
The results are shown in Table 1.

[0045]

[Table 1]

(Extrusion conditions)

[0047]

[Table 2]

(Specification of spiral die used) [Inner die ring]-Number of spiral strips (number of spiral flow grooves) 32 A resin side 16 B resin side 16-Number of turns of flow path 1-Spiral pitch 5.156 mm starting point and the groove depth and width groove depth at the end (mm) width (mm) a resin-initiated point 5 3.5 endpoint 0 0 B resin side start point of the spiral pitch angle 27.7 ° spiral flow path groove 5 3.5 End point 0 0-The size of the gap between the spiral ridge and the outer die ring and its change in the extrusion direction Start point 0.5 mm End point 1.25 mm-The diameter of the inner die ring and its change in the extrusion direction Start point 100mm End point 97.5mm [Drive unit]-Drive motor 3.0KW ES servo motor-Reducer worm reducer-Drive method Chain method [Measurement Law] 1. Breaking stress, breaking elongation, yield stress According to JIS K-7127, Orientec Co., Ltd.
It measured using the Tensilon type universal tester RTM-100 manufactured under the following conditions.

Sample length (distance between grips) 50 mm Sample width 10 mm Crosshead speed 500 mm / min Test temperature 23 ° C. Test humidity 50% relative humidity Young's modulus According to JIS K 7127, Orientec Co., Ltd.
It measured on the following conditions using the Tensilon universal tester RTM-100 manufactured.

Sample length (distance between grips) 100 mm Sample width 20 mm Crosshead speed 10 mm / min Test temperature 23 ° C. Test humidity 50% relative humidity

[0051]

As apparent from Table 1 above, in Comparative Example 1 using the fixed spiral die, the number of laminations in the thickness direction was 14 to 15 layers. In Examples 1 to 5 in which the number of rotations was changed from -0.1 rpm to +4 rpm, the number of laminations in the thickness direction could be widely increased and decreased from 10 to 11 layers to 55 to 57 layers, and the resulting laminated film was obtained. It can be seen that the breaking stress, breaking elongation, Young's modulus, and yield point stress can be adjusted.

[Brief description of the drawings]

FIG. 1 is a sectional view of a conventional spiral die for a multilayer and a sectional view of a product film.

FIG. 2 is a perspective view and a cross-sectional view in two directions of a laminated resin film obtained by using the spiral die of FIG.

FIG. 3 is a cross-sectional view of an example of a previously developed fixed spiral die and a cross-sectional view of a product film.

FIG. 4 is a schematic perspective view of a main part of the spiral die of FIG. 3;

5A and 5B are a perspective view and a cross-sectional view of an example of a laminated resin film manufactured by the spiral die of FIG.

FIG. 6 is a schematic sectional view of an example of an apparatus system including the rotary spiral die of the present invention and a sectional view of a product film.

FIG. 7 is an enlarged perspective view of an inner die ring in a section XX of FIG. 6;

FIG. 8 is a structural view of a flow path of a distribution part of the resin A inside of FIG.

FIG. 9 is a structural diagram of a flow path of a distribution part of the resin B inside of FIG.

FIG. 10 is an axial sectional view of the rotary spiral die of FIG. 6;

FIG. 11 is a perspective view and a two-directional cross-sectional view of an example of a laminated film obtained by the rotating spiral die of FIGS. 6 to 10;

FIG. 12 is a schematic cross-sectional view of another example of the device system including the rotating spiral die of the present invention.

[Explanation of symbols]

1: laminated resin film (1a, 1b: two main surfaces thereof) A, B: constituent resin species 10a, 10b, 10c, 20a, 20b: extruder 11, 21: spiral die 121: rotary spiral die 12a, 12b, 22a , 22b: die ring 122a: rotating inner die ring 122b: fixed outer die ring 22ab: gap flow path between inner and outer die rings 13a, 23a1, 23a2, 23a3, 23b1, 2
3b2, 23b3: Tournament branch 14a, 24a, 24b: Spiral flow channel 15a, 15b, 15c, 25: Cylindrical flow channel 16: Confluence 17, 27: Die lip 28a, 28b: Distributing unit final flow channel 31: Sprocket 32: Chain 33: Motor 34: Rotating channel cover 35: Bearing 36: Resin leakage port 37: Shaft

Claims (6)

[Claims] 1. An inner die ring and an outer die ring,
A plurality (m; m, respectively) of which the depth is gradually reduced on the inner die ring side between the inner die ring and the outer die ring, wherein at least one of them is rotatably disposed in a fitting relationship with each other. Is a natural number), and a plurality of spiral flow grooves (n; n is a natural number and n <m) are formed in the plurality (m) of spiral flow grooves.
A distribution groove for distributing and introducing a molten resin flow composed of different resins in a predetermined order is provided, and the individual resin flows supplied through the distribution groove from the inner die ring advance in the spiral flow channel to form a die shaft. Before forming a uniform cylindrical flow in the direction, the plurality of molten resin flows are laminated as a leakage flow from the spiral flow channel in a certain order, and the spiral for forming a laminate is characterized in that Die. 2. The spiral die according to claim 1, wherein the inner die ring is rotatable. 3. The spiral die according to claim 1, wherein m is 4 to 256 and n is 2 to 4. 4. The spiral die according to claim 1, wherein the distribution groove is provided on the inner die ring in a structure that is not exposed on a sliding surface between the opposing outer die ring. 5. An inner die ring and an outer die ring,
A plurality (m; however, where the depth is gradually reduced, on the inner die side between the inner die and the outer die, wherein at least one of them is rotatably arranged in a fitting relationship with each other. (m is a natural number) spiral spiral grooves formed with spiral flow grooves formed in the plurality of (m) spiral flow grooves while rotating at least one of the die rings from the inner die ring to the plural (n). Where n is a natural number and n <m), the molten resin flows composed of different resins are distributed and introduced in a certain order through distribution grooves formed in the inner die ring, and the individual resin flows are formed into spiral flows. Before forming a uniform cylindrical flow in the die axis direction by advancing the path groove, by laminating the plurality of molten resin flows as a leakage flow from the spiral flow path groove in the certain order. Laminate manufacturing method characterized by obtaining the laminated tubular body in which the plurality resin are stacked obliquely in the circumferential direction section. 6. The method according to claim 5, further comprising an inflation step for expanding and reducing the thickness of the laminated tubular body.