JP3303338B2 - Modified polyester and film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a modified polyester and a film, and more particularly, to an excellent adhesive property,
The present invention relates to a modified polyester and a film having transparency and flatness. More specifically, photographic supports,
The present invention relates to a modified polyester and a film having excellent adhesiveness, transparency and flatness suitable for packaging, general industrial use, magnetic tape and the like, and further having good heat resistance.

[0002]

2. Description of the Prior Art Polyester, especially polyethylene terephthalate, polybutylene terephthalate or poly-terephthalate
1,4-Cyclohexane dimethylene terephthalate and polyesters based on these have excellent physical and chemical properties, and are widely used as fibers, films or sheets, and also as molded articles thereof. I have.

In particular, polyester films have excellent properties in heat resistance, chemical resistance, and mechanical properties, and are used in many applications such as magnetic tape, electric, photographic, packaging, and drafting. Have been.

[0004] However, generally, polyester has a problem that it is inferior in adhesiveness and printability with hydrophilic ink. Conventionally, a method of applying a corona discharge treatment to a film surface or coating an adhesive substance to improve the adhesiveness of a polyester film is known. However, these methods have the drawback that not only the steps are complicated and the cost is increased, but also the transparency and the like of the film are reduced.

Therefore, these steps are not required, and the base
Attempts have been made to improve the adhesion from the film itself. For example, Japanese Patent Application Laid-Open No. 52-151365 discloses that a polyalkylene glycol is used to copolymerize a polyether segment to improve the adhesiveness and printability of a film, but its properties are not sufficient.

On the other hand, as a photographic support, a plastic film made of polyester such as triacetyl cellulose and polyethylene terephthalate is generally used. However, although the polyester film has excellent mechanical properties, transparency and dimensional stability, it is difficult to handle the film after development because rolled curl remains strongly in the roll form. Its scope has been limited to use in sheet-like form, such as film for use.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art. In particular, the present invention has excellent adhesiveness without requiring any extra high-order processing, and has excellent transparency and curl. An object of the present invention is to provide a modified polyester and a film satisfying the curl recovery property, the mechanical properties, and the heat resistance.

[0008]

SUMMARY OF THE INVENTION The object of the present invention is to provide an ester-forming compound having a trifunctional or higher functionality of 0.1 to 3.0% by weight based on a polyester and an ether represented by the following formula (I). This is achieved by a modified polyester comprising from 1 to 20% by weight of a bond-containing dicarboxylic acid or an ester-forming derivative thereof. R ² OOC (CH ₂ ) p O (C _k H _2k O) m (R ¹ O) q (C _j H _2j O) n (CH ₂ ) p COOR ³ (I) (where R ¹ is A divalent hydrocarbon group having 4 or more carbon atoms, R ² and R ³ are the same or different and represent hydrogen or an alkyl group, and k and j each independently represent 2 to 4;
, Q is 0 or 1, p is an integer of 1 to 3, m and n are each independently an integer of 0 or more, and m + n is 3
0-500).

The polyester used in the present invention is a polyester comprising an aromatic dicarboxylic acid or an alicyclic dicarboxylic acid and diol as main components. Examples of the aromatic dicarboxylic acid component include terephthalic acid, isophthalic acid and phthalic acid. Acid, 1,4-naphthalenedicarboxylic acid, 1,
5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 4,4
Aromatic dicarboxylic acids such as' -diphenyletherodicarboxylic acid and 4,4'-diphenylsulfonedicarboxylic acid can be mentioned, and 1,4-cyclohexanedicarboxylic acid and the like can be mentioned as alicyclic dicarboxylic acid components. Can be. These acid components may be used in combination of two or more,
Further, aliphatic dicarboxylic acids such as adipic acid, suberic acid, sebacic acid and dodecandioic acid, and oxy acids such as hydroxyethoxybenzoic acid may be partially copolymerized.
As the diol component, for example, ethylene glycol
1,2-propanediol, 1,3-propanediol, neopentyl glycol, 1,3-butanediol
1,4-butanediol, 1,5-pentanedio-
1,6-hexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol
Aliphatics such as 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, polyalkylene glycol, and 2,2′-bis (4′-β-hydroxyethoxyphenyl) propane; Alicyclic and aromatic diols can be mentioned. These diol components may be used alone or in combination of two or more. Representative examples of the base polyester include polyethylene terephthalate, polybutylene terephthalate,
Examples include polyethylene naphthalate and poly-1,4-cyclohexane dimethylene terephthalate.

The trifunctional or higher functional ester-forming compound in the present invention may be any of aliphatic, alicyclic and aromatic as long as it has a trivalent or higher functional ester-forming functional group. Examples of the ester-forming functional group include a carboxyl group, a -COOR group (R is a monovalent organic group),-
COX group (X is a halogen atom), hydroxyl group, -OCOR '
Groups (R ′ is a monovalent organic group) and the like. Here, R and R 'are not particularly limited as long as they are monovalent organic groups, but are preferably lower aliphatic hydrocarbon groups such as a methyl group and an ethyl group. These ester-forming functional groups may have only the same kind in the molecule, or may have different kinds. Such compounds include trimellitic acid, hemmellitic acid, trimesic acid,
Trinitrate or higher polycarboxylic acids such as prenit acid, melophanic acid and pyromellitic acid and their ester-forming derivatives such as esters, acid anhydrides and acid halides, glycerol, sorbitol, trimethylolpropane, pentaerythritol, Trivalent or higher polyols such as 2,6,6-tetramethylolcyclohexanol and 1,3,5-trimethylolbenzene, and their ester-forming derivatives, 2,4-dioxybenzoic acid, 4-oxyisophthalic acid, , 5-dioxyterephthalic acid, glyceric acid and their ester-forming derivatives such as esters, acid anhydrides and acid halides. Among the above compounds, a trifunctional compound is particularly preferable,
A carboxyl group is preferred as the functional group. Among them, trimellitic acid and trimethyl trimellitate are more preferably used.

The amount of the ester-forming compound having three or more functional groups must be 0.1 to 3.0% by weight, preferably 0.1 to 1.0% by weight, based on the polyester (namely, the base polyester) used in the present invention. 5% by weight.

If the amount of the tri- or higher functional ester-forming compound is less than 0.1% by weight, sufficient adhesive performance and curl curl recovery cannot be obtained. on the other hand,
If the content is more than 3.0% by weight, gelation occurs, so that film formation is difficult or the mechanical strength of the obtained film is undesirably reduced.

The dicarboxylic acid having an ether bond or an ester-forming derivative thereof according to the present invention is represented by the following formula (I). ^{_{R 2 OOC (CH 2) p}} O (C k H 2k O) m (R 1 O) q (C j H 2j O) n (CH 2) p COOR 3 (I) In the above formula, R ¹ is It is a divalent hydrocarbon group having 4 or more carbon atoms, preferably a divalent hydrocarbon group having an integer of 4 to 8 carbon atoms. Further, R ¹ may include halogen, oxygen, and sulfur. For example, a linear or side chain aliphatic hydrocarbon group such as tetramethylene, hexylene and 2,2-dimethylpropylene, an aliphatic hydrocarbon group having an aliphatic ring such as cyclohexylene, and an aromatic hydrocarbon such as phenylene And the like.

In the above formula, k and j are each independently an integer of 2 to 4, q is 0 or 1, and p is 1 to
The integer of 3, m and n are each independently an integer of 0 or more, and m + n is 30 to 500. m + n is 500
If the ratio exceeds the above, there may be a problem that the transparency is reduced. Further, m + n is particularly preferably from 60 to 300.
n is preferably 30 to 500. Where R ² and R
³ is the same or different and represents hydrogen or an alkyl group, preferably hydrogen or a lower alkyl group having 1 to 4 carbon atoms. The molecular weight of the ether-containing dicarboxylic acid or its ester-forming derivative is 500 to 2500 in terms of average molecular weight from the viewpoint of mechanical properties and transparency.
It is preferably in the range of 0, more preferably 1000 to 2
Those in the range of 0000, particularly 2,000 to 10,000 are preferred.

Particularly preferred dicarboxylic acids having an ether bond or an ester-forming derivative thereof are those represented by the following formula (II). R ² OOCCH ₂ O (C ₂ H ₄ O) _n CH ₂ COOR ³ (II) (R ² and R ³ are the same as defined above, and n is an integer of 4 or more.) The amount of the bond-containing dicarboxylic acid or the ester-forming derivative thereof is 1 to 20 with respect to the polyester (namely, the base polyester) used in the present invention.
% By weight, preferably 3 to 17% by weight,
More preferably, it is 5 to 15% by weight. If the amount is less than 1% by weight, the adhesive performance and the curl curl recovery property are not sufficient.

The method of copolymerizing or containing the tri- or higher functional ester-forming compound and the ether-containing dicarboxylic acid or its ester-forming derivative of the present invention into a base polyester is not particularly limited. The method and timing of blending or addition to the base polyester are arbitrary and not particularly limited. It may be blended and added to the base polyester in powder or molten state. The compounding and addition may be carried out at any time during the base polyester synthesis reaction, in a molten state after the reaction is completed, in a pellet state, or before molding. In particular, it is preferable to mix and add the compound between before and after the reaction in the base polyester synthesis reaction.

As a specific method for producing the modified polyester of the present invention, for example, a polyethylene terephthalate-based modified polyester comprising a terephthalic acid component and an ethylene glycol component will be described. Terephthalic acid, a trifunctional or higher functional ester-forming compound (for example, trimellitic acid) and an ether bond-containing dicarboxylic acid are directly esterified with ethylene glycol, or dimethyl terephthalate is trifunctional or higher functional ester. Reaction in the first step of transesterifying an unsaturated compound (eg, trimethyl trimellitate) and an ester-forming derivative of an ether bond-containing dicarboxylic acid with ethylene glycol, and the reaction product of the first step B. a second step of performing a polycondensation reaction; This reaction product is polycondensed after the completion of the first step of directly esterifying or transesterifying terephthalic acid or its ester-forming derivative or a trifunctional or higher ester-forming compound with ethylene glycol. A method in which an ether bond-containing dicarboxylic acid or an ester-forming derivative thereof is added and arbitrarily added until the polyester is produced by the second step of the reaction, and the like, may be mentioned.

At this time, as a reaction catalyst, conventionally known alkali metals, alkaline earth metals, manganese, cobalt, zinc, antimony, germanium, titanium compounds and the like are used. Good.

The glass transition temperature of the modified polyester of the present invention is preferably 35 ° C. or higher, more preferably 45 ° C. or higher, and particularly preferably 50 ° C. or higher. If the glass transition temperature of the modified polyester is lower than 30 ° C., the heat resistance of the formed film is lowered, and the film is undesirably thermally deformed.
The intrinsic viscosity of the modified polyester of the present invention is preferably 0.3 or more, more preferably 0.4 or more, and particularly preferably 0.5 or more, in order to increase the strength of the formed film.

The modified polyester and film of the present invention may optionally contain a flame retardant, a heat stabilizer, an ultraviolet absorber,
Pigments, dyes, fatty acid esters, organic lubricants such as waxes or antifoaming agents such as polysiloxanes may be blended, and for the purpose of imparting lubricity and the like, clay, mica, titanium oxide, calcium carbonate, kaolin, Wet and dry method silica, colloidal silica, inorganic particles such as calcium phosphate, barium sulfate, and alumina, and organic particles containing acrylic, styrene, and the like as constituents may be blended.

After drying, the modified polyester obtained above is supplied to a known melt extruder, extruded into a sheet from a slit die, and solidified by cooling to form an unstretched sheet. The desired film can be obtained by biaxially stretching the unstretched sheet. As the stretching method, a sequential stretching method or a simultaneous biaxial stretching method can be used. In the case of the sequential biaxial stretching method, stretching is generally performed in the order of the longitudinal direction and the width direction. However, the stretching may be performed in the reverse order. Although the stretching ratio is not particularly limited, it is usually appropriate that the stretching ratio is 2.0 to 5.0 times each in the vertical and horizontal directions.
After biaxial stretching, the film may be stretched again in either the longitudinal or transverse direction. Further, after that, the film of the present invention may be heat-treated. The heat treatment conditions are not particularly limited, but usually 180 to 230 ° C. and the time is suitably 0.5 to 60 seconds.

In the melt extrusion, a film having a multilayer structure comprising the modified polyester of the present invention and another polymer may be obtained. The number of layers of the multilayer film is not particularly limited, but is preferably two or three. The thickness ratio between the modified polyester of the present invention and the other polymer is not particularly limited, but in the case of a two-layer film, preferably, one layer of the modified polyester of the present invention has a thickness of 10% of the total thickness of the multilayer film. %, Particularly preferably at least 20%. In the case of a film having three or more layers, the total thickness of the layers comprising the modified polyester of the present invention is at least 10% of the total thickness of the multilayer film, and particularly preferably at least 20%. The layer made of the modified polyester of the present invention may be in the outermost layer or the inner layer of the multilayer film, but from the viewpoint of adhesiveness, at least one outermost layer of the multilayer film is the modified polyester of the present invention. Preferably, there is. Other polymers used for the laminated film are not particularly limited,
Typical examples thereof include polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, poly-1,4-cyclohexane dimethylene terephthalate, and other known components are partially copolymerized with these. You may.

By providing a surface layer material such as an undercoat layer and a halogenated emulsion layer on at least one surface of the film of the present invention, a photographic material using the film of the present invention as a support can be obtained.

From the modified polyester of the present invention, fibers and other molded products can be produced according to a conventional method in addition to the above-mentioned film.

[0025]

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. Intrinsic viscosity of modified polyester: [η] Measured at 25 ° C. using o-chlorophenol solvent.

B. Glass transition temperature (Tg) and melting point (Tm) of the modified polyester were measured by a differential scanning calorimeter.

C. The film obtained from the transparency-modified polyester was subjected to ASTM-D
The film haze was measured according to 1003-59.

D. Adhesiveness Aluminum was vapor-deposited on the surface of the film obtained from the modified polyester, and a cellophane tape was pressed on the vapor-deposited surface, and the state was determined when the film was peeled. A: No peeling on the cellophane tape side. ；: The portion peeled off on the cellophane tape side is 20% or less. Δ: A portion of 20% to 70% is peeled to the cellophane tape side. X: 70% or more of the portion was peeled to the cellophane tape side.

E. Breaking strength 10mm width from film obtained from modified polyester
A sample having a length of 50 mm was prepared and measured at a tensile speed of 300 mm / min.

F. Curled curl recoverability 35mm width from film obtained from modified polyester
Make a 133mm long sample, wind it around a 10mm diameter core,
70 ° C. × 30% RH × 72 hr, then
After being released from the core and immersed in distilled water at 40 ° C. for 30 minutes, the sample is suspended vertically, a load of 30 g is applied, and the sample is dried in a 50 ° C. air thermostat for 5 minutes. The processed film sample was placed on a flat surface, and it was evaluated how much the sample length was recovered with respect to the original sample length of 133 mm.

G. Heat shrinkage 10 mm width from film obtained from modified polyester
A sample having a length of 250 to 300 mm is prepared, the sample is weighted by using a 3 g clip, and the sample is treated in a hot air oven set at 80 ° C. I asked.

Example 1 100 parts by weight of dimethyl terephthalate, 0.5 part by weight of trimethyl trimellitate, 70 parts by weight of ethylene glycol, and 0.1% of magnesium acetate as a transesterification catalyst.
06 parts by weight, 0.002 parts by weight of lithium acetate and 0.03 parts by weight of antimony trioxide as a polycondensation reaction catalyst were subjected to a transesterification reaction according to a conventional method, and then 0.023 parts by weight of trimethyl phosphate was added. After that,
10 parts by weight of polyethyleneoxydiglycolic acid (PEOG) HOOCCH ₂ O (C ₂ H ₄ O) _n CH ₂ COOH having an average molecular weight of 4000 was added as a dicarboxylic acid containing a ter bond. Then, the temperature was gradually increased and the pressure was reduced, and finally a polycondensation reaction was performed at 280 ° C. and 1 mmHg or less to obtain a modified polyester. The intrinsic viscosity measured at 25 ° C. using an o-chlorophenol solvent was 0.60, and the Tg was 57.
° C. The obtained modified polyester was formed into a film at 275 ° C. by a film forming machine, and then stretched by a biaxial stretching machine at a longitudinal stretching ratio of 3.3 times and a transverse stretching ratio of 3.5 times.
A film having a thickness of 60 μ was obtained by heat treatment at ℃. Table 2 shows the properties of the obtained film.

The haze of the film was 0.7%, the adhesion was good, and the curl recovery was evaluated. The heat shrinkage at 80 ° C. is 0.4%.
Met.

Comparative Example 1 In the same manner as in Example 1, a polyester and a film to which only trimethyl trimellitate was not added were obtained. The intrinsic viscosity of the polyester was 0.62, and both the adhesion and the transparency were good, but the curl recovery was poor at 50%. Table 2 shows the results.

Examples 2 to 5 and Comparative Examples 2 to 4 As described in Table 1, various 3
Modified polyesters and films were obtained by changing the types and amounts of the ester-forming compound having functionality or higher and the dicarboxylic acid containing an ether bond.

[Table 1] The abbreviations in the table indicate the following compounds.

TMTM: Trimethyl trimellitate PEOG: Polyethylene oxydiglycolic acid HOOCCH ₂ O (C ₂ H ₄ O) _n CH ₂ COOH Example 6 Melt extrusion using the modified polyester used in Example 1 and polyethylene terephthalate. At this time, after forming a three-layer laminate in which both outer layers were the modified polyester and the inner layer was polyethylene terephthalate, the same method as in Example 1 was used, and the overall film thickness was 60 μm, the outer layer was both 15 μm and the inner layer was 30 μm. Was obtained.

Example 7 The modified polyester and polyethylene terephthalate used in Example 1 were melt-extruded to form a two-layer laminate in which one layer was the modified polyester and the other layer was polyethylene terephthalate. In the same manner as in Example 1,
A two-layer film having a total thickness of 60 μm and both layers of 30 μm was obtained.

The properties of the resulting modified polyester and film are shown in Table 2. (However, since Examples 6 and 7 are not a single composition, [η] and Tg are not described.)

[Table 2] Examples 2 to 7 were within the scope of the present invention, and all were good in film haze, adhesiveness, curl recovery and heat shrinkability. On the other hand, Comparative Example 2 did not use PEOG, and although the haze of the film was good,
Both adhesiveness and curl recovery were poor. In Comparative Example 3, the amount of the trifunctional or higher functional ester-forming compound was outside the range of the present invention, and gelation occurred during the polymerization, so that a stable polymer could not be obtained. In Comparative Example 4, the amount of the dicarboxylic acid containing an ether bond was out of the range of the present invention, and it was soft and lacked self-supporting property, and a film could not be formed.

[0040]

As described above, the present invention relates to a modified polyester containing a specific amount of a trifunctional or more functional ester-forming compound and a dicarboxylic acid having an ether bond or an ester-forming derivative thereof with respect to the base polyester. It is a film having excellent adhesiveness, transparency, curl curl recovery, and heat resistance, and is preferably used for photographic supports, packaging, general industrial use, magnetic tape, and the like.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08G 63/00-63/91

Claims (3)

(57) [Claims] 1. A polyester having 0.1 to 3.0% by weight of an ester-forming compound having a functionality of 3 or more based on a polyester represented by the following formula:
A modified polyester comprising 1 to 20% by weight of an ether bond-containing dicarboxylic acid represented by (I) or an ester-forming derivative thereof. R ² OOC (CH ₂ ) p O (C _k H _2k O) m (R ¹ O) q (C _j H _2j O) n (CH ₂ ) p COOR ³ (I) (where R ¹ is A divalent hydrocarbon group having 4 or more carbon atoms, R ² and R ³ are the same or different and represent hydrogen or an alkyl group, and k and j each independently represent 2 to 4;
, Q is 0 or 1, p is an integer of 1 to 3, m and n are each independently an integer of 0 or more, and m + n is 3
0 to 500 ) 2. A film comprising the modified polyester according to claim 1. 3. A film having a multilayer structure, at least one of which is the modified polyester according to claim 1.