Stock material or miscellaneous articles – Composite – Of polyester
Patent
1986-03-07
1987-10-13
Van Balen, William J.
Stock material or miscellaneous articles
Composite
Of polyester
360134, 428694, 428900, G11B 564, G11B 566, B32B 2718, B32B 2736
Patent
active
046998454
DESCRIPTION:
BRIEF SUMMARY
DESCRIPTION
1. Technical Field
The present invention relates to an easily-adhesive polyester film that is excellent in the bondability.
More particularly, the present invention relates to an easily-adhesive polyester film having a coating layer formed on one surface of a polyester film.
2. Background Art
Recently, polyester films have been broadly used as bases for magnetic media such as magnetic tapes and magnetic disks, capacitors and photographic films.
In the application fields of polyester films, it is required that the bondability be good. For example, when a polyester is used as a base of a magnetic tape, a good adhesion is necessary between the polyester base film and the magnetic layer. However, a polyester film itself, especially a biaxially stretched film of polyethylene terephthalate, is poor in the bondability, and various studies have been made so as to improve the bondability. As means for improving the bondability of a polyester film, there is known a corona discharge treatment of the film surface, an ultraviolet ray irradiation treatment of the film surface and a plasma treatment of the film surface. However, these treatments are defective in that the resulting bondability is not sufficient and the bondability changes with the passing of time. Furthermore, there is known a method in which a urethane resin or acrylic resin is coated on the surface of a polyester film. However, when this coated polyester film is wound on a roll, laps of the film adhere to each other and so-called blocking is caused, resulting in reduction of the operation efficiency and breakage of the film.
It is therefore a primary object of the present invention to provide an easily-adhesive polyester film in which the above-mentioned defects of the conventional techniques are eliminated and the bondability and blocking resistance are improved.
DISCLOSURE OF THE INVENTION
According to the present invention, the above object is attained by an easily-adhesive polyester film comprising a polyester base film and a coating layer formed on one surface of the polyester base film, the coating layer comprising a mixture composed mainly of a copolyester comprising as one comonomer component an alkali metal salt of an ester-forming aromatic sulfonic acid and a higher fatty acid wax.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing the manner of lapping a film and the direction of the force when the force of separating the laps of the film from each other is measured.
BEST MODE FOR CARRYING OUT THE INVENTION
In the present invention, the copolyester comprising the alkali metal salt as one comonomer component is a copolyester obtained by polycondensing (A) a dicarboxylic acid or an ester-forming derivative thereof with (B) a glycol. An alkali metal salt of an ester-forming aromatic sulfonic acid is copolymerized as a part of the dicarboxylic acid or its easter-forming derivative as the component (A).
It is preferred that the component (A) should comprise at least 60 mole% of an aromatic dicarboxylic acid or an ester-forming derivative thereof and 7 to 40 mole% (especially 10 to 20 mole%) of an alkali metal salt of an ester-forming aromatic sulfonic acid or an ester-forming derivative thereof and that the component (B) should comprise at least 40 mole% of an aliphatic or alicyclic glycol. Furthermore, diethylene glycol or triethylene glycol may be used in an amount of 1 to 60 mole%, preferably 1 to 18 mole%, as a part of the glycol component (B). The bondability can be improved by using a copolyester having the above-mentioned composition.
As the aromatic dicarboxylic accid component forming the copolyester of the present invention, there can be mentioned terephthalic acid, isophthalic acid, phthalic acid, 2,5-dimethylterephthalic acid, 1,4-naphthalene-dicarboxylic acid, biphenyldicarboxylic acid, 2,6-naphthalene-dicarboxylic acid, 1,2-bis(phenoxy)-ethane-p,p'-dicarboxylic acid, and ester-forming derivatives thereof. As the ester-forming derivative, there are generally used lower alkyl esters of these di
REFERENCES:
patent: 3779993 (1973-12-01), Kibler et al.
patent: 4590119 (1986-05-01), Kawakami et al.
Supplementary European Search Report (Appln EP 85903381) Annex to European Search Report (EP 85903381).
Chem. Abstracts, 92:148141s, Watanabe, H., "Laminated Polyester Films".
Izasa Takao
Oikawa Tatuo
Okabe Kazuo
Toray Industries Inc.
Van Balen William J.
LandOfFree
Easily-adhesive polyester film does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Easily-adhesive polyester film, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Easily-adhesive polyester film will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-411048