JP3289439B2 - Polyester film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to relates to Po Li ester film. For details, antistatic properties, water solubility,
Water-soluble copolymerized polyester that has excellent adhesiveness, blocking resistance, solvent resistance, etc. and is suitable as a coating agent for films used in magnetic recording materials, various photographic materials, packaging materials, electrical insulating materials, general industrial materials, etc. It relates to the used polyester film.

[0002]

2. Description of the Related Art Polyesters, especially polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate or poly-1.4-cyclohexane dimethylene terephthalate, and polyesters based thereon have excellent physical and chemical properties. , Fibers, films or sheets, and molded articles thereof. In particular, polyester films have excellent properties in heat resistance, chemical resistance, and mechanical properties, and are used in many applications such as magnetic recording materials, various photographic materials, packaging materials, electrical insulating materials, and general industrial materials. I have.

[0003] In these applications, the polyester film is not used alone, and various coatings such as a magnetic coating material, a chemical mat coating material, a diazo photosensitive coating material, a gelatin composition, a heat sealing composition, Used by applying or printing ink or the like. For this reason, the following properties are required for polyester films used for various applications.

(1) It has a large adhesive strength to various coatings applied and printed on the film surface. (2) Further, if a blocking phenomenon occurs between the base films, workability is reduced, so that the blocking phenomenon does not occur (blocking resistance). (3) When passing through various rolls in the product manufacturing process, no charging phenomenon occurs due to friction between the roll and the film or between the films (running antistatic property). (4) It has resistance to various solvents in various coatings applied and printed on the film surface.

[0005] In particular, films used for magnetic recording materials such as magnetic tapes and floppy disks are required to have flatness and smoothness for high reliability and high density of magnetic recording. strong.

However, since the polyester itself is inactive and poor in adhesion, the polyester film has various adhesions, for example, magnetic paints, on the film surface.
When applying or printing a chemical mat paint, a diazo photosensitive paint, a gelatin composition, a heat-sealing composition, an ink, etc., a corona discharge or plasma is applied to the film surface to improve the adhesiveness with the coating. Physical treatment, a chemical treatment using an alkali or an amine chemical, and a method of coating an easily adhesive substance. However, the physical or chemical surface treatment method complicates the process, not only increases the cost, but also does not provide sufficient adhesiveness.

On the other hand, the method of coating an easily adhesive substance can be carried out in the process of producing a polyester film, is advantageous in cost, and can select an adhesive substance which can cope with various coatings. is there. Furthermore, various water-dispersed or water-soluble copolymerized polyesters and films have been proposed from the viewpoint of handleability of polyester films and workability during film production. For example, JP-B-47-40873, JP-A-50-121336 and JP-A-50-134086 disclose polyesters obtained by copolymerizing an ester-forming metal salt compound of sulfonic acid and polyethylene glycol, and polyesters thereof. Laminated film, JP-A-63-6623
No. 9 discloses a polyester obtained by copolymerizing an ester-forming metal salt compound of sulfonic acid and polytetramethylene glycol.
JP-A-2536 and JP-A-54-3848 disclose ester-forming sulfonic acid metal salt compounds, polyesters obtained by copolymerizing an aliphatic dicarboxylic acid component and diethylene glycol, and JP-A-59-215318 discloses an ester-forming sulfone. Examples include a film undercoated with a polyester obtained by copolymerizing an acid metal salt compound and an aliphatic dicarboxylic acid component.

[0008]

However, the above-mentioned prior art has the following problems. That is, when a large amount of an ester-forming sulfonic acid metal salt compound and a low molecular weight polyethylene glycol are copolymerized as disclosed in JP-B-47-40873, water solubility and adhesiveness are exhibited, but blocking resistance and solvent resistance are exhibited. Poor performance and insufficient running antistatic performance. JP 5
When a large amount of an ester-forming sulfonic acid metal salt compound and a polyalkylene glycol component are copolymerized as disclosed in JP-A Nos. 0-121336, 50-134086, and 63-66239, water solubility is increased. ,
Poor blocking resistance and solvent resistance are not preferred. Further, Japanese Patent Application Laid-Open Nos. 50-83497 and 53-253
No. 6, JP-A-54-3848 and JP-A-5-3848.
As described in JP-A-9-215318, when an ester-forming sulfonic acid metal salt compound and an aliphatic dicarboxylic acid component, and further diethylene glycol are copolymerized, adhesiveness is exhibited, but the blocking resistance is poor and the running antistatic property is poor. There are drawbacks such as not being able to obtain.

The present invention has been intensively studied in order to solve these drawbacks. As a result, the use of a copolymerized polyester having a specific molecular weight distribution and containing a residue having an alkali metal sulfonic acid salt base provides water-soluble and solvent-resistant compounds. It has been found that it is possible to improve the adhesiveness, and at the same time, provide the adhesiveness, the anti-blocking property, and the antistatic property for running. The present invention uses magnetic recording material, various photographic materials, wrapping material, electrical insulating material, a suitable co-polyester in the coating agent of the film used for the general industrial materials and the like
A polyester film. In particular,
An object of the present invention is to provide a polyester film using a water-soluble copolymerized polyester suitable for a coating agent for a film used for a magnetic recording material or the like.

[0010]

An object of the present invention is to include a residue having a sulfonate alkali metal base,
Copolyester having a number average molecular weight of 2000 or more and the component amount of a molecular weight of 1,000 or less is 10 wt% or less
Consisting of a layer consisting of
Polyester layer is particles and / or organic lubricant
Can be achieved by a polyester film containing

The polyester in the present invention is a polyester containing an aromatic dicarboxylic acid or an alicyclic dicarboxylic acid and a glycol as main components. Examples of the aromatic dicarboxylic acid component include terephthalic acid, isophthalic acid, phthalic acid, and naphthalene. Dicarboxylic acid, diphenyl dicarboxylic acid, diphenyl ether dicarboxylic acid and the like can be mentioned, and as the alicyclic dicarboxylic acid component,
For example, 1,2-cyclohexanedicarboxylic acid, 1,3-
Examples thereof include cyclohexanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid. These acid components may be used alone or in combination of two or more. As the glycol component, a polyester using an aliphatic glycol having 2 to 8 carbon atoms and an alicyclic glycol having 6 to 16 carbon atoms is preferable, and an aliphatic glycol having 2 to 8 carbon atoms and an aliphatic glycol having 6 to 16 carbon atoms are preferable. Examples of the alicyclic glycol include ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, and 1,5-pentane. Glycols such as diol, 1,6-hexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol and the like can be mentioned. These glycol components may be used alone or in combination of two or more. In addition,
The glycol component also contains a glycol by-produced during the production of the polyester.

Examples of the polyester comprising these components include, for example, polyethylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, polycyclohexane dimethylene terephthalate, polyethylene naphthalate, and / or copolymerized polyesters thereof. Polyethylene terephthalate, polyethylene naphthalate and / or their copolymerized polyesters are preferred.

The copolyester of the present invention must contain a residue having an alkali metal sulfonate group, and the components constituting the residue having an alkali metal sulfonate include an ester-forming alkali metal sulfonate. Salt compounds, for example, alkali metal salts such as sulfoterephthalic acid, 5-sulfoisophthalic acid, 2-sulfoisophthalic acid, 4-sulfoisophthalic acid, and 4-sulfonaphthalene-2,6-dicarboxylic acid can be given. 5
-Lithium, sodium and potassium salts of sulfoisophthalic acid and sulfoterephthalic acid are more preferably used.

The component constituting the residue having the alkali metal sulfonic acid base is preferably from 1 to 50 mol% based on the total acid component constituting the copolymerized polyester from the viewpoint of water solubility and adhesiveness. And more preferably 5 to 40 mol%, particularly preferably 10 to 20 mol%. When the amount of the component constituting the residue having the sulfonic acid alkali metal base is within the above range with respect to all the acid components constituting the copolymerized polyester, sufficient water solubility and adhesion can be obtained,
The running antistatic property, blocking resistance, and solvent resistance are improved.

In addition to the above-mentioned dicarboxylic acid component and glycol component, the copolymerized polyester of the present invention may contain an aliphatic dicarboxylic acid, an oxyacid or a monofunctional compound or a trifunctional or higher polyfunctional compound as long as the effects of the present invention are not impaired. Etc. may be included.

The copolymerized polyester containing a residue having an alkali metal sulfonic acid base according to the present invention has a number average molecular weight of 2
000 or more and the molecular weight of 1000 or less
% By weight, preferably a component having a number average molecular weight of 2500 or more and a component having a molecular weight of 1000 or less being 8% by weight or less, and a component having a molecular weight of 500 or less being 6% by weight or less, and more preferably a number average molecular weight. Is 3000 or more,
The amount of the component having a molecular weight of 1000 or less is 5% by weight or less, the amount of the component having a molecular weight of 500 or less is 4% by weight or less, particularly preferably the number average molecular weight is 3500 or more and the amount of the component having a molecular weight of 1000 or less is 4% by weight or less. The component amount of 500 or less is 3% by weight or less. If the number average molecular weight of the copolymerized polyester containing a residue having a sulfonic acid alkali metal base is less than 2,000, or if the amount of the component having a molecular weight of 1,000 or less exceeds 10% by weight, poor water solubility or poor solvent resistance will result. May be. In particular, when the amount of the component having a molecular weight of 1,000 or less exceeds 10% by weight, various coatings such as a magnetic paint, a chemical mat paint, and the like are provided on a polyester film provided with a copolymerized polyester layer containing a residue having a sulfonate alkali metal base. When applying or printing a diazo photosensitive paint, gelatin composition, heat seal imparting composition, ink, etc., it dissolves in solvents in various coatings to be applied or printed, or reacts with substances in the coating. As a result, foreign substances are deposited on the surface of the coating. The foreign matter significantly reduces the commercial value. In particular, a magnetic recording material such as a magnetic tape or a floppy disk using a magnetic coating material has a drawback that high reliability of magnetic recording cannot be obtained. For this reason, it is preferable that the number average molecular weight of the copolymerized polyester containing a residue having a sulfonic acid alkali metal base is as large as possible, and the amount of components having a molecular weight of 1,000 or less is as small as possible.

The copolyester containing a residue having an alkali metal sulfonic acid base according to the present invention has a running antistatic property,
It is preferable that the polyoxyalkylene glycol component is contained from the viewpoint of solvent resistance, and the content of the polyoxyalkylene glycol component in the copolymerized polyester containing a residue having a sulfonate alkali metal base is particularly limited. However, it is preferably less than 50% by weight, more preferably less than 20% by weight, and particularly preferably 18% by weight or less based on the total copolymerized polyester. When the polyoxyalkylene glycol component content is 50% by weight or more, water solubility, blocking resistance, running antistatic property,
The solvent resistance may be poor.

Although the type of the polyoxyalkylene glycol component of the present invention is not particularly limited, the number average molecular weight of the polyoxyalkylene glycol component is 400 to 400 from the viewpoint of having both water solubility, antistatic property and solvent resistance. 100
00, more preferably 500 to 600 in number average molecular weight.
0 is preferable, and particularly, a number average molecular weight of 600 to 4000 is preferable. Examples of such a polyoxyalkylene glycol component include polyethylene glycol, polypropylene glycol, polytetramethylene glycol and the like. Among them, water-soluble, antistatic,
Polyethylene glycol is preferred from the viewpoint of solvent resistance.

The method for incorporating the polyoxyalkylene glycol component of the present invention into the copolymerized polyester is not particularly limited. For example, a method in which the polyoxyalkylene glycol component is added at any stage of the production process of the copolymerized polyester, Alternatively, a method of melt-kneading the copolymerized polyester and the polyoxyalkylene glycol component using an extruder or the like can be used. At this time, the polyoxyalkylene glycol component can be added by any method such as powder, melting or solution. In addition, the polyoxyalkylene glycol component in the present invention contains a polyoxyalkylene glycol produced as a by-product during the production of polyester.

The production of the copolymerized polyester containing a residue having an alkali metal sulfonic acid base of the present invention can be carried out by any conventionally known method, and is not particularly limited. For example, a copolymer polyester composed of terephthalic acid as an acid component, 5-sodium sulfoisophthalic acid, and ethylene glycol as a glycol component and polyethylene glycol as a polyoxyalkylene glycol component will be described.
A first step of directly performing an esterification reaction with 5-sodium sulfoisophthalic acid and ethylene glycol or a transesterification reaction with an alkyl ester of terephthalic acid, an alkyl ester of 5-sodium sulfoisophthalic acid and ethylene glycol, and And the second step of performing a polycondensation reaction of the reaction product of the step. In this case, the polyoxyalkylene glycol component is added at any stage in the production process of the copolymerized polyester. A copolymerized polyester containing a residue having a sulfonic acid alkali metal base of the present invention can be produced. At this time, a conventionally known alkali metal, alkaline earth metal, manganese, cobalt, zinc, antimony, germanium, titanium compound or the like is used as a reaction catalyst, and a phosphorus compound or the like may be used as a coloring inhibitor.

The number average molecular weight of the copolymerized polyester containing a residue having an alkali metal sulfonic acid base of the present invention is 20.
The method for reducing the amount of the component having a molecular weight of not less than 00 and the molecular weight of not more than 1000 to 10% by weight or less is a first step of transesterifying an acid component and a glycol component among the above-described examples of the method for producing a copolymerized polyester; And a second step in which the reaction product of the first step is subjected to a polycondensation reaction. The polyoxyalkylene glycol component is added from the first step after the end of the transesterification reaction to the time before the start of the polycondensation reaction. It is preferably performed in the second stage.

At this time, at any stage of the production process of the copolyester, the alkali metal compound is added to the copolyester so that the alkali metal content in the entire copolyester is 1 to 500 mol / mol.
It is preferable to add the copolymerized polyester so as to be 10 ⁶ g. More preferably an alkali metal content of 5 to 100 mol / total copolyester 10 ⁶ g in the total copolyester. Examples of the alkali metal compound herein include lithium chloride, lithium hydride, lithium salts of aliphatic carboxylic acids, lithium salts of aromatic carboxylic acids, lithium compounds such as lithium carbonate, and sodium compounds and potassium compounds. it can. Alkali metal content 1 mol / Total copolymerized polyester 10
If the amount is less than ⁶ g, in the production reaction step of the copolymerized polyester of the present invention, diethylene glycol or the like may be generated, or a side reaction that inhibits the polycondensation reaction may occur, or the molecular weight of the obtained copolymerized polyester may be 1,000 or less. May increase in component amount. If the alkali metal content exceeds 500 mol / 10 ⁶ g of the total copolymerized polyester, there may be a problem that foreign substances are formed in the copolymerized polyester. Further, in the second stage of the polycondensation reaction in the production process of the copolymerized polyester, the reaction conditions for producing a normal polyester such as polyethylene terephthalate can be employed. The reaction temperature is preferably 275 ° C. or lower, more preferably 270 ° C. or lower. Since the side reaction can be suppressed by lowering the polycondensation reaction temperature, the amount of the component having a molecular weight of 1,000 or less of the copolymerized polyester containing a residue having a sulfonate alkali metal base of the present invention can be reduced.

The copolymerized polyester of the present invention may contain a flame retardant, a heat stabilizer, an ultraviolet absorber, a pigment, a dye,
Organic lubricants such as fatty acid esters and waxes or antifoaming agents such as polysiloxanes may be blended, and clay, mica, titanium oxide, calcium carbonate, kaolin, wet and dry silica are used for the purpose of imparting lubricity. , Colloidal silica, calcium phosphate, barium sulfate, inorganic particles such as alumina, and even acrylic acids,
Organic particles containing styrene or the like as a constituent may be blended.

The polyester film of the present invention is composed of a layer made of the copolymerized polyester of the present invention containing a residue having an alkali metal sulfonate group and a polyester layer. With such a polyester layer,
For example, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate or poly-
Examples thereof include, but are not limited to, 1.4-cyclohexane dimethylene terephthalate, aromatic polyesters based on these, and copolymerized polyesters thereof. The production method is not particularly limited, and any conventionally known method can be adopted. Further, in that case, the polyester layer such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate or poly-1.4-cyclohexane dimethylene terephthalate and an aromatic polyester based on these may be a laminated film of two or more layers. The lamination structure is not particularly limited. Further, the polyester layer such as the aromatic polyester may contain a lubricant composed of inorganic particles and organic particles having an average particle diameter of 0.001 to 10 μm.

A specific method for producing a polyester film in the case where polyethylene terephthalate is used as the polyester layer and the polyester layer containing a residue having a sulfonic acid alkali metal base of the present invention will be described first. After drying, it is melt extruded into an unstretched sheet, followed by heat treatment,
Turn into film. The biaxial stretching may be any of longitudinal and transverse sequential stretching or simultaneous biaxial stretching, and the stretching ratio is not particularly limited, but is usually 2.0 to 5.0 for each of longitudinal and transverse.
Double is appropriate. After the biaxial stretching, the film may be further stretched in any of the longitudinal and transverse directions. At this time, the polyester film of the present invention is obtained by applying an aqueous solution of a copolymerized polyester containing a residue having an alkali metal sulfonic acid base of the present invention to the film surface. The aqueous solution of the copolymerized polyester containing a residue having a sulfonate alkali metal base can be produced by any method. For example, it can be produced by dissolving the copolymerized polyester in water at 40 ° C. or higher, preferably 60 ° C. or higher. The concentration of the copolymerized polyester in the aqueous solution is not particularly limited, but is preferably 0.1 to 50% by weight. Preferably, more preferably, 0.
5 to 30% by weight, especially 1.0 to 10% by weight is preferred. This aqueous solution does not have strictness in a physical or chemical sense, and includes an aqueous solution which is mostly dissolved in water and partially finely dispersed. In addition, when the copolymerized polyester containing a residue having a sulfonic acid alkali metal base is made water-soluble or in an aqueous solution, higher fatty acid compounds, for example, higher aliphatic monocarboxylic acid compounds such as arachiic acid, behenic acid, montanic acid, and erucic acid , Higher aliphatic monocarboxylic acid ester compounds such as ethylene glycol montanate, ethyl montanate, octacosyl lignoserate, and seryl citrate, and carboxyl and hydroxyl groups by oxidizing the ethylene chain portion of the wax by air oxidation or the like. Such as oxidized wax and natural wax, for example, organic lubricants such as montan wax, carnauba wax, beeswax, nuka wax, ibota wax, clay, mica, titanium oxide, calcium carbonate, kaolin, wet and dry silica, colloidal Silica, Li Inorganic particles having an average particle size of 0.001 to 2 μm, such as calcium acid, barium sulfate, and alumina, and organic particles having an average particle size of 0.001 to 2 μm containing acrylic acid, styrene, and the like as constituents are blended. Is preferable from the viewpoint of blocking resistance and lubricity. In particular, a natural wax such as an oxidized wax having a molecular weight of 1,000 or more and / or carnauba wax has an average particle diameter of 0.0
Inorganic particles such as colloidal silica, titanium oxide, and alumina having a size of from 1 to 2 μm are preferred. The compounding amount of these organic lubricants, particles and the like is preferably 0.01 to 70% by weight, more preferably 0.5 to 5% by weight, based on the copolymerized polyester in the aqueous solution.
0% by weight, particularly preferably 1.0 to 30% by weight.

The aqueous polyester film solution containing a residue having a sulfonate alkali metal base is applied to the film surface by a conventionally known coating method, for example, a reverse coating method, a gravure coating method, a die coating method, or a wire bar method. Can be used. The coating is preferably carried out during the production process of the polyester film. More preferably, the unstretched sheet is heated to 80 to 120 ° C., stretched uniaxially in either the vertical or horizontal direction, and then coated with an aqueous solution of the copolymerized polyester. Then, while continuously heating to 90 to 140 ° C., the film is stretched in a direction different from the uniaxial stretching.
A method of producing the polyester film of the present invention by leading to a heat treatment zone of 240 ° C. and performing heat treatment for 1 to 20 seconds is preferable.

In the polyester film of the present invention, the thickness of the layer composed of the copolymerized polyester containing a residue having a sulfonate alkali metal base is not particularly limited, but is preferably in the range of 0.001 to 5.0 μm. Further, 0.01 to 2.0 μm, particularly 0.05 to 0.5 μm
Is preferred. When the thickness of the layer composed of the copolymerized polyester is within the above range, good adhesion, antistatic properties and blocking resistance can be obtained. The thickness of the layer made of the copolymerized polyester containing a residue having a sulfonic acid alkali metal base can be measured by various methods.For example, a cross section of the polyester film can be observed with an electron microscope,
When the layer made of the copolymerized polyester can be removed with a solvent or the like, it can be determined from the difference in thickness between the removed portion and the unremoved portion.

The polyester film comprising a polyester layer and a polyester layer containing a polyalkylene glycol component and containing a residue having a sulfonate alkali metal base according to the present invention is particularly suitable for running antistatic properties and solvent resistance. The charge amount is preferably -6 KV or more to +6 KV or less.

[0029]

The present invention will be described in more detail with reference to the following examples. The characteristics in the examples were measured as follows.

A. The molecular weight of the copolymerized polyester was measured by GPC-LARLS (low-angle laser light scattering photometer).

B. Water solubility of copolymerized polyester 5 g of copolymerized polyester is put in 100 g of water,
After stirring and dissolving at 2 ° C. for 2 hours and cooling, the mixture was filtered through a 1 μm filter. The water solubility of the copolymerized polyester was determined based on the dissolved state and the amount of the residue on the filter. A: The aqueous solution was almost transparent, and no residue was found on the filtration. ：: The aqueous solution was slightly cloudy, but almost no filtered product was observed. Δ: The aqueous solution was slightly cloudy, and a filtered product was observed. X: It was difficult to dissolve, or the aqueous solution was strongly cloudy, and a large amount of filtered product was observed.

C. Adhesiveness An aqueous solution of a copolymerized polyester is applied, and Diferacoat VD1654 (manufactured by Dainichi Seika Kogyo Co., Ltd.) 100 parts by weight and Sumidur N75 (manufactured by Sumitomo Bayer Co., Ltd.) 1 wt. Part of the coating material after drying was applied with a bar coater to a thickness of 5 μm.
After drying for a minute, a coating layer was provided. A cellophane adhesive tape is applied to the surface of the coating layer, and after passing through a nip roll with a linear pressure of 50 kg / cm, the tape is rapidly peeled in a direction of 180 degrees. At that time, the area of the coating layer adhered to the cellophane pressure-sensitive adhesive tape was determined to determine the adhesiveness. ：: The area of the coating layer adhered to the cellophane adhesive tape is 5%
Less than that, and excellent in adhesiveness. Δ: Area of coating layer adhered to cellophane adhesive tape was 5%
２０20% or less, and the adhesion is slightly inferior. ×: The area of the coating layer adhered to the cellophane adhesive tape was 20.
% Or more and is inferior in adhesiveness.

D. Blocking resistance An aqueous solution of a copolymerized polyester is applied, and the adhesive layer surfaces of the film provided with the adhesive layer are superposed (a) and the film surface having no adhesive layer is provided on the adhesive layer surface of the film provided with the adhesive layer. After the superposed product (b) (superimposed area: 3 cm × 4 cm) was applied with a load of 500 g / 12 cm ² and left at 60 ° C. and 80% RH for 72 hours,
The shear stress at the overlapped portion was measured using a Tensilon tensile tester at a tensile speed of 20 cm / min.

E. Solvent resistance An aqueous solution of a copolymerized polyester was applied, and methyl ethyl ketone was dropped as an organic solvent onto the surface of the adhesive layer of the film provided with the adhesive layer. ：: Almost no cloudiness. Δ: slightly cloudy X: Cloudy.

F. Film surface condition after application of magnetic paint An aqueous solution of a copolymerized polyester is applied, and Diferacoat VD1654 (manufactured by Dainichi Seika Kogyo Co., Ltd.) {100 parts by weight and Sumidur N75} (Sumitomo Bayer) Coating (1% by weight) manufactured by Co., Ltd. is applied with a bar coater so as to have a thickness of 5 μm after drying.
Dried for 60 minutes to form a coating layer, and dried at 60 ° C. and 80% RH for 7 minutes.
After standing for 2 hours, the surface condition of the coating layer surface was observed and judged. ：: The surface condition was good. Δ: Slight precipitates were observed on the surface. ×: Many precipitates were observed on the surface.

F. Antistatic property A polyester film without an easy-adhesion layer is wound around the surface of a rotating metal drum, and a load of 255 g is applied to the end of the easy-adhesion layer of the film in which the easy-adhesion layer is laminated while rotating.
And rub it along the metal drum rotating body for 5 seconds. Immediately after, the potential charged on the film was measured by an electrostatic measuring device, and the antistatic property was determined. Charge amount -6 KV or more to +6
The range below KV is preferred. Static meter: Stylon TH type manufactured by Shisido Electrostatic Co., Ltd. Measurement distance 50 mm from the head opening Metal drum rotating body: Dimension 65 mm width × 150 mm φ Number of rotations 860 rpm Measurement sample: 30 mm width × 300 mm length Example 1 Dimethyl terephthalate 71. 0 parts by weight, 14.8 parts by weight of dimethyl 5-sodium sulfoisophthalate, 51.6 parts by weight of ethylene glycol and 0.05 parts of manganese acetate
3 parts by weight of lithium acetate and 0.03 parts by weight of antimony trioxide were added, and the mixture was subjected to a transesterification reaction according to a conventional method, followed by 0.05 parts by weight of trimethyl phosphate and polyethylene glycol having a number average molecular weight of 600. 0 parts by weight were added.

Then, the temperature was gradually increased and the pressure was reduced.
A polycondensation reaction was performed at 70 ° C. and 1 mmHg or less to obtain a copolymerized polyester containing a residue having a sulfonate alkali metal base. The composition of the obtained copolymerized polyester is N
As a result of measurement by MR, the acid components were 88 mol% of terephthalic acid, 12 mol% of 5-sodium sulfoisophthalic acid,
The glycol component was 95 mol% of ethylene glycol and 5 mol% of diethylene glycol, and the content of polyethylene glycol was 15% by weight. The number average molecular weight of the copolymerized polyester was 6,400, and the molecular weight was 100.
The amount of components having a molecular weight of 0 or less was 3.3% by weight, and the amount of components having a molecular weight of 500 or less was 2.0% by weight.

5 g of the obtained copolyester was added to water 10
0 g, and dissolved by stirring at 80 ° C. for 2 hours.
The solution was filtered through a μm filter to obtain a copolymerized polyester aqueous solution. The aqueous solution of the copolymerized polyester was almost transparent, and no product was found on the filter. Furthermore, natural carnauba wax emulsified water was added to the aqueous solution of the copolymerized polyester such that the carnauba waxed water was 7.0% by weight based on the copolymerized polyester.

On the other hand, after sufficiently drying polyethylene terephthalate having an intrinsic viscosity of 0.60 dl / g containing 0.2% by weight of silicon dioxide having an average particle diameter of 0.2 μm, it is supplied to an extruder and melted at 290 ° C. The sheet was extruded into a sheet form from a T-type die and cooled and solidified with a cooling drum at 30 ° C. to obtain an unstretched film. Next, the unstretched film is heated to 95 ° C.
And stretched 3.4 times in the machine direction to obtain a uniaxially stretched film. Further, the aqueous solution of the copolymerized polyester obtained above was applied to one surface of the uniaxially stretched film by gravure coating so that the coating thickness after biaxial stretching was 0.1 μm. Subsequently, the mixture was heated to 100 ° C. and 3.5
The film was stretched twice and heat-treated at 200 ° C. to obtain a 15 μm-thick polyester film having a copolymerized polyester layer containing a residue having a sulfonate alkali metal base. Table 1 shows the characteristic results of the obtained film. The film had good adhesion, blocking resistance, solvent resistance, and antistatic properties. The surface condition of the film after applying the magnetic paint was also good.

Examples 2 and 3 In the same manner as in Example 1, the type of the polyoxyalkylene glycol was changed to obtain a copolymerized polyester containing a residue having an alkali metal sulfonic acid base. Table 1 shows the properties of the copolymerized polyester. The number average molecular weight of the copolymerized polyester and the amount of components having a molecular weight of 1,000 or less were within the scope of the present invention, and were excellent in water solubility.

Further, various additives shown in Table 1 were added to the aqueous solution of the copolymerized polyester, and a copolymerized polyester layer containing a residue having a sulfonate alkali metal base was prepared in the same manner as in Example 1. A polyester film was obtained. Table 1 shows the characteristic results of the obtained film. The film had good adhesion, blocking resistance, solvent resistance, and antistatic properties. The surface condition of the film after applying the magnetic paint was also good.

[0042]

[Table 1] Examples 4 to 6 In the same manner as in Example 1, the amounts of the acid component and the polyoxyalkylene glycol and the reaction conditions were changed to obtain a copolymerized polyester and a film containing a residue having a sulfonate alkali metal base.

Table 2 shows the characteristic results of the copolymerized polyester and the film. Examples 4 to 6 are within the scope of the present invention, and the water solubility of the copolymerized polyester, the adhesiveness of the film, the blocking resistance, the solvent resistance, the antistatic property, and the surface state after applying the magnetic paint are all good. there were.

[0044]

[Table 2] Comparative Example 1 83.6 parts by weight of dimethyl terephthalate, 17.4 parts by weight of dimethyl 5-sodium sulfoisophthalate, 60.7 parts by weight of ethylene glycol, 0.2 parts by weight of manganese acetate, and 0.03 parts by weight of antimony trioxide In addition, after a transesterification reaction according to a conventional method, 0.05 parts by weight of trimethyl phosphate was added. Subsequently, the temperature was gradually increased and the pressure was reduced, and finally a polycondensation reaction was performed at 295 ° C. and 1 mmHg or less, to obtain a copolymerized polyester containing a residue having a sulfonate alkali metal base. The composition of the obtained copolymerized polyester was measured by NMR. As a result, the acid component was 88 mol% of terephthalic acid, 12 mol% of 5-sodium sulfoisophthalic acid, and the glycol component was ethylene glycol 90.
Mol% and 10 mol% of diethylene glycol. Further, the number average molecular weight of the copolymerized polyester is 2500, the amount of components having a molecular weight of 1,000 or less is 11.0% by weight, and the molecular weight is 5%.
The component amount of 00 or less was 6.2% by weight.

5 g of the obtained copolyester was added to 10 parts of water.
0 g, and dissolved by stirring at 80 ° C. for 2 hours.
The solution was filtered through a μm filter to obtain a copolymerized polyester aqueous solution. The aqueous solution of the copolymerized polyester was slightly turbid, and a filtered product was observed. Further, natural carnauba wax emulsified water was added to the aqueous solution of the copolymerized polyester so that carnauba wax was 7.0% by weight based on the copolymerized polyester, and the same method as in Example 1 was used. A polyester film having a copolymerized polyester layer containing a residue having a sulfonate alkali metal base was obtained. Table 3 shows the characteristic results of the obtained film. The film was inferior in solvent resistance and had a charge amount of -9 kV and poor antistatic properties. Further, deposited foreign substances were observed on the film surface after the application of the magnetic paint.

Comparative Example 2 37.6 parts by weight of dimethyl terephthalate, 7.8 parts by weight of dimethyl 5-sodium sulfoisophthalate, 27.3 parts by weight of ethylene glycol, 0.05 part by weight of manganese acetate, 0.3 part by weight of lithium acetate Parts, number average molecular weight 600
55 parts by weight of polyethylene glycol and 0.03 parts by weight of antimony trioxide were added, and the mixture was subjected to a transesterification reaction according to a conventional method, and then 0.05 parts by weight of trimethyl phosphate was added. Then, the temperature was gradually raised and reduced, and finally 295
A polycondensation reaction was carried out at 1 ° C. or lower at 1 ° C. to obtain a copolymerized polyester containing a residue having an alkali metal sulfonic acid base. The composition of the obtained copolymerized polyester was analyzed by NMR.
As a result, the acid component was 88 mol% of terephthalic acid, 12 mol% of 5-sodium sulfoisophthalic acid, the glycol component was 93 mol% of ethylene glycol and 7 mol% of diethylene glycol, and the polyethylene glycol content was 51% by weight. Met. The number average molecular weight of the copolymerized polyester was 8900 and the molecular weight was 1000.
The amount of the following components was 12.7% by weight, and the amount of the components having a molecular weight of 500 or less was 6.5% by weight.

5 g of the obtained copolyester was added to 10 parts of water.
0 g, and dissolved by stirring at 80 ° C. for 2 hours to obtain a copolymerized polyester aqueous solution. The aqueous solution of the copolymerized polyester was strongly clouded. All aqueous solutions could not be filtered through a 1 μm filter. Further, natural carnauba wax emulsified water was added to the aqueous solution of the copolymerized polyester, and 7.0% by weight of carnauba wax was added to the copolymerized polyester.
And a polyester film having a copolymerized polyester layer containing a residue having a sulfonate alkali metal base was obtained in the same manner as in Example 1. Table 3 shows the characteristic results of the obtained film. The film was inferior in solvent resistance and had a charge amount of +14 kV and also had poor antistatic properties. In addition, a large number of deposits were observed on the film surface after the application of the magnetic paint.

[0048]

[Table 3]

[0049]

As described above, the present invention contains a residue having a sulfonate alkali metal base and has a number average molecular weight of 2
000 or more and the molecular weight is 1000 or less
Weight percent or less of copolyester layer and polyester
Consisting of a tellurium layer and consisting of the above-mentioned copolymerized polyester
A polyester film in which the layer contains particles and / or an organic lubricant , improves water solubility and solvent resistance,
And adhesion, blocking resistance, excellent running antistatic properties, magnetic recording material, various photographic materials, packaging materials, electrical insulating materials, fill beam used for general industrial materials and the like, in particular audio, video, floppy disks, etc. preferably used fill beam used in a magnetic recording material.

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C08G 63/00-63/91

Claims (9)

(57) [Claims] 1. A layer comprising a copolyester containing a residue having a sulfonate alkali metal base, having a number average molecular weight of 2,000 or more and a molecular weight of 1,000 or less in an amount of 10% by weight or less. And polyester
And a layer comprising the above-mentioned copolymerized polyester.
Polyester containing particles and / or organic lubricant
Film . 2. A copolymer polyester having a number average molecular weight of 2
The polyester film according to claim 1, wherein the content of the component having a molecular weight of 500 or more and the molecular weight of 1000 or less is 8% by weight or less, and the content of the component having a molecular weight of 500 or less is 6% by weight or less. 3. A polyester film according to claim 1 or 2 wherein the copolyester is comprised 1-50 mol% of residues having the alkali metal sulfonate. 4. The copolyester contains 5 to 40 mol% of a residue having a sulfonic acid alkali metal base, and the copolyester is water-soluble.
The polyester film as described. 5. The polyester film according to claim 1, wherein the copolymerized polyester contains a polyoxyalkylene glycol component. 6. The polyester film according to claim 5, wherein the polyoxyalkylene glycol component is polyethylene glycol having a number average molecular weight of 400 to 10,000. 7. A polyoxyalkylene glycol component is less than 20% by weight relative to the total copolymerized polyester 請
7. The polyester film according to claim 5 or 6. Polyester film according to any one of claims 8] claims 1 to 7, the polyester layer are composed of more than at least two layers. 9. The method according to claim 1, which is used for a magnetic recording material .
The polyester film according to any one of the above.