Wire enamels containing polyesterimides and/or...

Details Wire enamels containing polyesterimides and/or... Wire enamels containing polyesterimides and/or...

1999-03-30

2001-11-13

Woodward, Ana (Department: 1711)

Coating processes

Electrical product produced

Wire conductor

C427S120000, C524S538000, C525S397000, C525S427000, C525S432000, C525S436000

Reexamination Certificate

active

06316046

ABSTRACT:

FIELD OF THE INVENTION
The invention relates to wire enamels, especially for thick circular and profiled wires, having improved adhesion to the wire, comprising as binders polyesterimide resins and/or polyamideimide resins which as monomer building blocks comprise polyoxyalkylenediamines having terminal amino groups.
BACKGROUND OF THE INVENTION
The wire enamels commonly employed today are in general solutions of the typical wire enamel binders, for example polyesters, polyesterimides and polyurethane resins, in organic solvents, alone or in combination with customary commercial hydrocarbon cuts. For use on wires of small to medium diameter, these enamels are available on the market in a sufficiently good quality. Wire enamels employed for the coating of thick round wires or for profiled wires, on the other hand, are subject—compared to the standard enamels—to particularly stringent requirements regarding the adhesion.
Polyesterimide enamels employed for wire coating are known, for example, from DE-A 1445263 and 1495100 and also WO 91/07469 (PCT-EP 90/01911). Because of their good mechanical, thermal and chemical properties they have found broad application in the coated-wire industry. In this case the polyesterimides are prepared in a known manner from polyols, polycarboxylic acids or derivatives thereof and imide-forming components. In general, such wire enamels satisfy the abovementioned stringent requirement regarding the adhesion to thick round or profiled wires only to a limited extent.
Likewise known are polyamideimides, used as binders for wire coating, which are described, for example, in U.S. Pat. No. 3,554,984, DE-A-24 41 020, DE-A-25 56 523, DE-A-12 66 427 and DE-A-19 56 512. Again, such polyamide-imide wire enamels only go a certain way toward meeting the abovementioned requirements regarding the adhesion.
The prior art has also disclosed polyimides which comprise polyoxyalkylenediamines as molecular building blocks.
In U.S. Pat. No. 4,116,937 Jeffamine® ED 900, an amine-terminated polyethylenepolypropylene glycol, is converted to a bismaleimide by reaction with maleic anhydride. In a formulation which also includes other bismaleimides, the material is extruded, in a complex procedure, onto a copper conductor and is cured at from 300 to 400 degrees F. A procedure of this kind is unsuitable in practice for the coating of wires. EP-A-0 329 833 describes the preparation of a hotmelt adhesive from an adduct of polyoxyalkylenediamine and trimellitic anhydride with an alkylenediamine. Such hotmelt adhesives are unsuitable for the coating of wires.
EP-A-0 281 003 describes a flame-resistant elastomer for injection molding applications, comprising a reaction product of an adduct of polyoxyalkylene diamine, alkanediol, trimellitic anhydride and dimethyl terephthalate and of melamine. Comparable reaction products without the melamine reaction component are described in EP-A-0 270 790. A synthetic rubber consisting of the reaction product of polyoxyalkylenediamine, trimellitic anhydride, a dimeric fatty acid and 1,4-butanediol is described in U.S. Pat. No. 4,544,734. The rubber has good thermal properties, is chemically resistant and can be extruded. In Journal Appl. Polym. Sci. (1982), 27 (11), pages 4295 to 4311, finally, a polyimide is described which likewise comprises polyoxyalkylenediamine as monomeric building block.
SUMMARY OF THE INVENTION
The object on which the present invention is based was therefore to provide wire coating compositions which avoid the disadvantages of the coating compositions known to date. The novel wire coating compositions should be stable on storage and have very good adhesion, especially to thick round and profiled wires, a high thermal pressure and a sufficient thermal shock. Furthermore, the wire coating compositions should have a very high solids content at a viscosity which is favorable for processing.
This object is surprisingly achieved by wire coating compositions comprising polyesterimide resins or polyamideimide resins which as monomeric building blocks comprise polyoxyalkylenediamines having terminal amino groups. The polyoxyalkylenediamines are preferably selected from the group polyoxyethylenediamine, polyoxypropylenediamine and polyoxyethylenepropylenediamine.
In this context, the polyoxyalkylenediamines are complete or partial replacements for the diamines and/or diisocyanates commonly used for the synthesis of the polyesterimides and/or the polyamideimides. In further preferred embodiments of the invention the wire enamels contain from 0.5 to 5% by weight of a phenolic resin or, in the case of a polyamideimide binder, of a phenolic resin and/or a melamine resin, from 0 to 2.5% by weight of catalysts, organic solvents or solvent mixtures, and, if desired, customary additives or auxiliaries.
Particularly preferred wire enamels are those based on the novel polyesterimides and composed of:
(A): 35 to 55% by weight
of the polyesterimide
resin
(B): 0.1 to 1.5% by weight
of the catalyst,
(C): 35 to 65% by weight
of the organic solvent
or solvent mixture,
(D): 1 to 4% by weight
of the phenolic resin
and/or melamine resin,
and
(E): 0 to 1% by weight
of customary additives
and auxiliaries,
the sum of components (A) to (E) making up 100% by
weight of the wire enamel.
Furthermore, particularly preferred wire enamels are those based on the novel polyesterimides and composed of:
(F): 25 to 35% by weight
of the polyamideimide
resin
(G): 0 to 1.5% by weight
of the catalyst,
(H): 55 to 80% by weight
of the organic solvent
or solvent mixture,
(I): 1 to 4% by weight
of the phenolic resin
and/or melamine resin,
and
(K): 0 to 1% by weight
of customary additives
and auxiliaries,
the sum of components (F) to (K) making up 100% by
weight of the wire enamel.


REFERENCES:
patent: 3554984 (1971-01-01), George
patent: 3959233 (1976-05-01), Hanson et al.
patent: 4116937 (1978-09-01), Jones et al.
patent: 4145334 (1979-03-01), Schmidt et al.
patent: 4145351 (1979-03-01), Schmidt et al.
patent: 4199651 (1980-04-01), Banucci et al.
patent: 4208464 (1980-06-01), Ishizuka et al.
patent: 4544734 (1985-10-01), McCready
patent: 4639486 (1987-01-01), Liu
patent: 5552254 (1996-09-01), Mychajlowsky et al.
patent: 5916996 (1999-06-01), Sacripante et al.
patent: 1445263 (1961-12-01), None
patent: 12 66 427 (1963-08-01), None
patent: 19 56 512 (1969-11-01), None
patent: 2441020 (1974-08-01), None
patent: 2556523 (1975-12-01), None
patent: 0 270 790 A2 (1987-10-01), None
patent: 0 281 003 (1988-02-01), None
patent: 0 329 833 (1988-11-01), None
patent: WO 88/09359 (1988-12-01), None
patent: 60-158222 (1985-08-01), None
patent: WO 91/07469 (1991-03-01), None
Journal of Applied Polymer Science, vol. 27, pp. 4295-4311, (1982), John Wiley & Sons, Inc.

Affiliated with

Also associated with

Rating

Wire enamels containing polyesterimides and/or... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Wire enamels containing polyesterimides and/or..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Wire enamels containing polyesterimides and/or... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2570922