JPH0952285A - Method and apparatus for winding solution casting sheet - Google Patents

Abstract

(57) Abstract: A sheet-like material produced by solution casting is appropriately embossed to prevent winding deviation. SOLUTION: When winding a solution-formed sheet-like object 10, a spherical projection 1 is formed at an end portion in the width direction of the sheet-like object 10.
Using the knurl ring 14 having the sheet 5,
A method and an apparatus for winding a solution film-forming sheet-like material which is embossed to form irregularities on the surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for winding a solution film-forming sheet-like material, and more particularly to a winding method and apparatus for winding a sheet-like material without causing misalignment.

[0002]

2. Description of the Related Art A sheet-like material such as a film made of aromatic polyamide is formed by casting a polymer solution in a thin film on a support such as a drum or an endless belt. Such a solution film-forming sheet material is usually
It is wound into a roll by a winder.

However, when the sheet-like material is wound into a roll, the air caught between the winding layers may cause the sheet-like material to float, which may cause misalignment, that is, the end surface position of the winding roll may be displaced. .

In winding a sheet-like material manufactured by a method other than solution casting, for example, as shown in FIGS. 6 and 7, the outer peripheral surface is relatively sharp at the upstream position of the winding roll 21. The knurl ring 23 having the protrusion 22 is provided, and the sheet-like material 25 is nipped between the knurl ring 23 and the opposing rubber roll 24,
An embossing process for forming irregularities on the edge of the sheet 25 may be performed. With this configuration, when the sheet-like material 25 is wound up, the irregularities formed on the sheet-like material 25 are engaged with each other, and the sheet-like material 25 is prevented from being misaligned.

[0005]

However, since many sheet-like materials produced by solution casting have a high Young's modulus and a low elongation, the knurl ring having the relatively sharp protrusions as described above is used. The embossing process causes perforations and the like in the sheet-like material, causing a problem that fragments of the generated holes are mixed in the product. Therefore, the solution casting film-like material was not subjected to the embossing treatment by the knurling.

An object of the present invention is to effectively prevent winding misalignment by embossing a sheet-like material produced by solution film formation.

[0007]

In order to solve the above-mentioned problems, a method for winding a solution film-formed sheet material according to the present invention is a method for winding a solution film-formed sheet material. The method is characterized in that the widthwise end portion is subjected to an embossing treatment for forming irregularities on the sheet-shaped material.

In particular, this embossing treatment is performed using a knurl ring having a plurality of spherical projections on its outer peripheral surface.

Further, the solution film-forming sheet-like product manufacturing apparatus according to the present invention includes a winding machine for winding the solution film-formed sheet-like product or immediately before the winding machine and at a widthwise end position of the sheet-like product. A knurl ring having a plurality of protrusions on the outer peripheral surface is provided for embossing to form irregularities on a sheet.

The protrusion of the knurl ring is formed by forming the tip of the protrusion into a spherical surface.

In such a winding method and apparatus, the sheet-shaped product formed by solution film is subjected to embossing treatment on the end in the width direction, so that when the sheet-shaped product is rolled up, The concavities and convexities formed on each winding layer by the embossing process are intermeshed with each other, and the winding deviation is appropriately prevented.

Since the embossing treatment is performed by using a knurl ring having a spherical projection, even a solution cast sheet having a low elongation or a solution cast sheet having a small thickness can be used. Also, a desired uneven shape is provided without causing perforation or the like.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a device for winding a solution film-forming sheet material according to an embodiment of the present invention. FIG. 4 shows a modified example of the protrusion shape of a knurl ring, and FIG. 5 shows a solution film-forming process. The outline of one embodiment of the sheet-like material manufacturing process is shown.

First, with reference to FIG. 5, an embodiment of a process for producing a sheet material by solution casting will be described. FIG.
1 shows the overall configuration of a solution casting film manufacturing apparatus according to an embodiment of the present invention. In the figure, reference numeral 1 denotes an extruder, and a polymer solution is fed into the extruder 1 as a raw material. The polymer solution extruded from the extruder 1 is discharged in a thin film form from the die 4 through the gear pump 2 and the filter 3. In the present embodiment, the discharged thin film 5 of the polymer solution is cast on a revolving endless belt 6 as a support, heated in an oven 7 and dried to be desolvated.

Subsequently, the thin film is cooled and formed by the cooling device 8 and, if necessary, stretched in the longitudinal direction. Cooling device 8
Is composed of a water-cooled device in this embodiment. The formed sheet (film) is guided to the tenter 9, dried, and stretched in the width direction as necessary. The thickness of the obtained film 10 is measured by the thickness measuring device 11, and if necessary, defects are detected online, and the film 10 is wound up by the winder 12.

The solution film-forming sheet according to the present invention is not particularly limited as long as it can be solution film-formed, and includes aromatic polyamide, triacetate, polycarbonate film and the like. Of these, the present invention is effective for aromatic polyamide films.

An aromatic polyamide film is a typical example of the solution film-forming film of the present invention. For example, when the aromatic polyamide is obtained from acid chloride and diamine, it is solution polymerized in an aprotic organic polar solvent such as N-methylpyrrolidone, dimethylacetamide, dimethylformamide, or interfacial polymerization using an aqueous medium. It is synthesized by. The polymer solution produces hydrogen chloride as a by-product when acid chloride and diamine are used as monomers, but when neutralizing this, calcium hydroxide, calcium carbonate,
Inorganic neutralizers such as lithium carbonate, and organic neutralizers such as ethylene oxide, propylene oxide, ammonia, triethylamine, triethanolamine and diethanolamine are used. The reaction between the isocyanate and the carboxylic acid is performed in an aprotic organic polar solvent in the presence of a catalyst.

These polymer solutions may be used directly as a film forming stock solution, or the polymer may be isolated once and then redissolved in the above organic solvent or an inorganic solvent such as sulfuric acid to prepare a film forming stock solution. Good.

The intrinsic viscosity of the aromatic polyamide film polymer (value measured at 30 ° C. in a solution of 0.5 g of the polymer in 100 ml of sulfuric acid) is preferably 0.5 or more.

Inorganic salts such as calcium chloride, magnesium chloride, lithium chloride, etc. are used as a dissolution aid in the stock solution for film formation.
In some cases, lithium nitrate or the like is added. The polymer concentration in the stock solution is preferably about 2 to 40% by weight.

Examples of the method for adding these particles include a method in which the particles are sufficiently slurried in a solvent in advance and then used as a solvent for polymerization or a solvent for dilution, or a method in which the particles are directly added after preparing a stock solution for film formation.

The stock solution for film formation prepared as described above is formed into a film by a so-called solution film forming method. The solution film-forming method includes a dry-wet method, a dry method, and a wet method, and any method may be used for film formation. Here, the dry-wet method shown in FIG. 5 will be described as an example.

When a film is formed by a dry-wet method, the stock solution is extruded from a die onto a support such as a drum or an endless belt made of a material such as nickel, stainless steel, copper, titanium, hastelloy, tantalum, and then applied. The solvent is scattered from the thin film layer and dried until the thin film has self-holding property. Drying conditions are in the range of room temperature to 250 ° C and within 60 minutes, preferably in the range of room temperature to 200 ° C. When the drying temperature exceeds 250 ° C, voids are generated due to rapid heating,
Roughness of the surface occurs, making it impossible to obtain a practical film as an industrial material or magnetic material.

The film that has undergone the dry process is peeled from the support and introduced into the wet process, where the solvent and impurities contained in the film are removed. This bath is generally composed of an aqueous medium, and may contain an organic solvent, an inorganic salt or the like in addition to water. However, in general, the water content is 30% or more, preferably 50% or more, and the bath temperature is usually 0 to 100 ° C. Further, the bath temperature is set to 50 to reduce impurities in the film.
It is effective to raise the temperature above ℃ or to pass a bath of organic solvent through it.

The film from the wet process is further stretched,
The film is dried and heat-treated to form a film.

The film formed as described above is stretched in the film-forming process, and the stretching ratio is 0.8 to 5.0 in terms of areal magnification (area is the film area after stretching). It is defined as a value divided by the area of the previous film. 1 or less means relax.), And more preferably 1.1 to 3.0. Further, the dimensional change rate can be reduced by gradually cooling the film after the heat treatment.

With respect to the aromatic polyamide film which is solution-cast as described above, the present invention particularly has a residual elongation of 80%.
It is also effective for the following films.

In the present invention, when the solution-formed film is wound up as described above, the widthwise end portion (either one end portion or both end portions) may be embossed. .

As shown in FIG. 1, when the film 10 is wound as a winding roll 13, a knurl ring 14 is provided in the winding machine or at a position immediately before the winding roll 13. Is embossed. A plurality of protrusions 15 are provided on the outer peripheral surface of the knurl ring 14, and the film 10 is nipped between the knurl ring 14 and the opposing rubber roll 16 with an appropriate pressing force, so that the film 10 is at a predetermined position. Is continuously embossed.

The protrusion 15 has, for example, as shown in FIG.
The protrusions 15 are arranged in a plurality of lines (three lines in the illustrated example).
Its tip is formed into a spherical surface. For example, as shown in FIG. 3, it is formed into a hemispherical protrusion having a radius of about 0.5 mm. The size of the spherical surface of the protrusion 15 is a radius of 0.
It is preferably about 2 to 5.0 mm. When the radius is more than 5 mm, the unevenness is less likely to remain on the film, and when it is less than 0.2 mm, it is difficult to form protrusions on the knurl ring 14. More preferably, the radius is 0.3 to 1.0 mm.

The material of the knurl ring 14 is not particularly limited, but SCM steel or the like is preferable. The number of the projections 15 on the knurl 14 is not particularly limited, but is preferably about 2 to 8 and more preferably 3 to 5.

Further, regarding the shape of the protrusion 15, FIG.
In addition to the hemispherical shape shown in Fig. 4, for example, as shown in Fig. 4, a projection 15a (Fig.
(A)), a projection 15b in which the tip of the trapezoidal body is formed into a spherical surface
(Fig. 4 (b)), a spherical projection 1 having a smaller protrusion than a hemisphere.
5c (FIG. 4C) or the like.

The embossing treatment according to the present invention is carried out by using the apparatus thus constructed. First, by performing embossing treatment on the solution-formed film 10,
Concavities and convexities are formed at the widthwise ends of the film 10, that is, at positions that do not serve as products. When the film 10 is wound up as the winding roll 13, the unevenness of each winding layer meshes with each other, so that even in the case of a solution film-forming film, winding deviation can be appropriately prevented.

Since the irregularities are formed by the spherical projections 15, the local stress applied to the film 10 when the irregularities are formed is appropriately relieved, and the occurrence of perforations is prevented. Therefore, even the solution-formed film can be embossed without causing any trouble.

[0035]

EXAMPLES The present invention will be described below with reference to examples. Example 1 An aromatic polyimide film having a thickness of 4.4 μm was embossed at the end of the film with a knurl ring having spherical projections having a radius of 0.5 mm as shown in FIG. 3 to form irregularities on the film. I wound up. As a result of observing the end portion of the wound film winding roll, no deviation occurred. Further, the embossed film was sampled, spread on a filter paper, and the ink was dripped from the film. When the ink permeation was confirmed, it was confirmed that the ink did not permeate and no holes were formed.

COMPARATIVE EXAMPLE 1 As shown in FIG. 8, an aromatic polyamide film having a thickness of 4.4 μm was embossed at its end with a knurl ring having a trapezoidal protrusion 15d having a height of 0.5 mm and an upper side of 0.4 mm. The film was processed to form irregularities on the film and wound up. Although the winding deviation did not occur, when the embossed film was confirmed by the above method, it was confirmed that many holes were formed by the protrusions.

[0037]

As described above, according to the present invention,
By performing embossing treatment on the solution-formed sheet-like material, it is possible to appropriately prevent misalignment during winding.

Further, by making the protrusion tip of the knurl ring used for the embossing process spherical, it becomes possible to form irregularities smoothly without generating perforations in the sheet-like material, and the solution-formed sheet-like material. Even in this case, the desired embossing process can be performed.

By preventing the winding deviation, the production stability is greatly improved, and by preventing the perforation, it is possible to prevent the occurrence of troubles such as the mixing of fragments into the product.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a winding device according to an embodiment of the present invention.

FIG. 2 is an enlarged partial perspective view of the knurl ring of FIG.

FIG. 3 is an enlarged side view of a protrusion of the knurl ring of FIG.

4 (a), (b), and (c) are side views showing a modified example of the protrusion of the knurl ring.

FIG. 5 is a schematic configuration diagram of a sheet-shaped material manufacturing apparatus by solution casting.

FIG. 6 is a schematic configuration diagram of a conventional embossing device.

FIG. 7 is an enlarged partial perspective view of the knurl ring of FIG. 6.

FIG. 8 is a side view of a protrusion of a knurl ring used in a comparative example.

[Explanation of symbols]

 10 Film as Solution-Forming Sheet Sheet Material 13 Winding Roll 14 Knurl Ring 15, 15a, 15b, 15c Protrusion 16 Opposing Rubber Roll

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] December 1, 1995

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Fig. 4

[Correction method] Change

[Correction contents]

FIG. 4 is a side view showing each modified example of the protrusion of the knurl ring.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B29L 7:00

Claims (5)

[Claims] 1. A solution-formed sheet-shaped product, characterized in that, when a solution-formed sheet-shaped product is wound up, an embossing treatment for forming irregularities on the sheet-shaped product is applied to a widthwise end portion of the sheet-shaped product. How to wind things. 2. The method for winding a solution film-forming sheet according to claim 1, wherein the embossing treatment is performed using a knurled ring having a plurality of spherical projections on the outer peripheral surface. 3. The method for winding a solution-formed sheet according to claim 1, wherein the solution-formed sheet is a film made of aromatic polyamide and having a residual elongation of 80% or less. 4. A winding machine for winding a solution film-formed sheet material or immediately before the winding machine for embossing treatment for forming irregularities on the sheet material at the widthwise end positions.
A winding device for a solution film-forming sheet, comprising a knurl ring having a plurality of protrusions on its outer peripheral surface. 5. The winding device for a solution film-forming sheet according to claim 5, wherein the tip of the protrusion is formed into a spherical surface.