Organic compounds -- part of the class 532-570 series – Organic compounds – Halogen containing
Reexamination Certificate
1997-01-27
2001-02-27
Siegel, Alan (Department: 1621)
Organic compounds -- part of the class 532-570 series
Organic compounds
Halogen containing
C570S129000, C570S143000, C570S144000, C570S184000, C528S401000
Reexamination Certificate
active
06194620
ABSTRACT:
The contents of Japanese patent application 7-254389 filed Aug. 25, 1995, are submitted with and incorporated by reference into this specification.
FIELD OF THE INVENTION
The present invention relates to dichloro-tetrafluoro-[2,2]-paracyclophane (formula I), which is a novel compound useful as a material for forming a coating film by chemical vapor deposition, and a process for manufacturing thereof and poly-&agr;&agr;-difluoro-chloro-para-xylylene film prepared therefrom.
According to the present invention, dichloro-tetrafluoro-[2,2]-paracyclophane (formula I) is manufactured by chlorinating tetrafluoro-[2,2]-paracyclophane of the following formula (II).
BACKGROUND OF THE INVENTION
[2,2]-paracyclophane and its derivatives of the following general formula (III)
wherein X means a substituent selected from a group consists of hydrogen, chlorine, bromine, fluorine and alkyl;
form a poly-para-xylylene film (including a nucleus-substituted poly-para-xylylene film; and forth) on a substrate by chemical vapor deposition through the following reactions. In the following formula, n means the degree of polymerization:
According to this coating method, it is possible to form coating films over substances of all shapes such that the films are true to the shapes, and thus formed polymeric thin films are excellent in gas barrier and electric characteristics and are widely used as materials of electronic parts or for coating of space apparatus.
However, a poly-para-xylylene film prepared from the compound of the above formula (III) has a limit in use in spite of its excellent characteristics. It is that said poly-para-xylylene film, though having a wide application range in vacuum and nitrogen, has a limited application temperature in atmosphere because the structure —CH
2
—CH
2
— binding benzene nuclei in its polymeric structure is liable to be oxidized. For example, this poly-para-xylylene film loses flexibility and strength as a film at 200° C. within about 30 minutes in atmosphere to get ragged only by slight rubbing though at variance to some degree with the presence or absence of a substituent of the benzene nuclei and the kind of substituent. As a countermeasure against this, it has been proposed to add an antioxidant into the film (See U.S. Pat. Nos. 4,176,209 5,267,390 and 5,270,082), which however brings no essential solution.
In order to broadly apply the poly-para-xylylene film in various fields, it is required to increase the thermostability of the film in the presence of oxygen.
It is known that a poly-para-xylylene of the following formula in which hydrogens of its methylene group are all substituted by fluorine
wherein n means the degree of polymerization,
has an outstanding thermostability. As to a process for manufacturing octafluoro-[2,2]-paracyclophane which is a starting material for the manufacture of this polymer, there are some patents and a patent application (see U.S. Pat. Nos. 3,268,599 3,274,267 and 3,297,591 and Japanese Patent Laid-open No. 255,149/1993).
However, mass production of these compounds is difficult and the films prepared therefrom have problems in adhering to substrates and the like. The objective of the present invention is to provide a new compound of the formula (I), dichloro-tetrafluoro-[2,2]-paracyclophane, which can be readily produced and is useful to form heat-resistant poly-paraxylylene film. Another objective of the present invention is to provide a highly thermostable poly-para-xylylene film prepared from said new compound.
DETAILED DESCRIPTION OF THE INVENTION
The present inventor intended to change the conventional poly-para-xylylene structure (IV) into a structure (V) (wherein n means degree of polymerization) in which 2 hydrogens of its methylene group on one side were substituted by fluorine as shown in the following structural formula so as to obtain a thermostable polymer in atmosphere. Thus, the inventor tried the synthesis of dichloro-tetrafluoro-[2,2]-paracyclophane (formula I) as a starting material for manufacturing said polymer as well as the polymerization and film formation by chemical vapor deposition thereof.
That is, the present invention comprises dichloro-tetrafluoro-[2,2] paracyclophane represented by the above formula (I), a process for manufacturing thereof and poly-&agr;,&agr;-difluoro-chloro-para-xylylene film prepared therefrom. The synthesis and the vapor deposition of this substance have never been tried.
The inventor of the present invention recently filed a patent application concerning tetrafluoro-[2,2]-paracyclophane, a process for manufacturing thereof and poly-&agr;,&agr;-difluoro-para-xylylene film prepared therefrom. The compound of the present invention, which is a dichloro derivative of the compound of the earlier invention, has various advantages over the compound of the earlier invention. For example, it can be coated more easily on a substrate by chemical vapor deposition than the earlier compound and the film prepared therefrom has more improved thermostability in atmosphere than that from the earlier compound. It is also expected that the film of the present invention has more improved characteristics such as gas barrier property than the film of the earlier invention.
As one example of processes, this substance was synthesized through the following route.
[2,2]-paracyclophane (formula VI) as a starting material is commercially available from Daisan Kasei Co., Ltd.
Tetrabromo-[2,2]-paracyclophane (formula VII) can be obtained by reacting [2,2] paracyclophane (formula VI) with a brominating agent such as N bromosuccinimide or the like in an inert solvent in the presence of a peroxide catalyst or under irradiation with UV light or under interaction of the both. In the bromination, although bromo compounds of the formula (VIII) and the like are also formed other than the aimed product, they can be separated based on the difference of solubility in the solvent.
Diketone-[2,2]-paracyclophane (formula IX) can be synthesized by a means of reacting soda acetate, silver acetate or the like with tetra-bromo-[2,2]-paracyclophane in an acetic acid solvent.
Tetrafluoro-[2,2]-paracyclophane (formula II) can be manufactured by reacting a fluorinating agent such as sulfur tetrafluoride, diethylaminosulfur trifluoride (hereinafter described as DAST) or the like with the above ketone compound.
The aimed compound dichloro-tetrafluoro-[2,2]-paracyclophane (formula I) was obtained by chlorination of tetrafluoro-[2,2]-paracyclophane.
The chemical vapor deposition of dichloro-tetrafluoro-[2,2]-paracyclophane (formula I) was carried out in compliance with the conditions which are generally applicable to [2,2]-paracyclophane and its derivatives (formula III), and decomposition of the present substance into radicals, polymerization thereof and film formation were tried.
REFERENCES:
patent: 3221068 (1965-11-01), Gorham
patent: 4783561 (1988-11-01), Pregaglia et al.
patent: 4795838 (1989-01-01), Bornengo et al.
patent: 4816608 (1989-03-01), Bornengo et al.
patent: 4849559 (1989-07-01), Lee et al.
patent: 4853488 (1989-08-01), Ungarelli et al.
patent: 5210341 (1993-05-01), Dolbier et al.
patent: 5536892 (1996-07-01), Dolbier et al.
patent: 5679874 (1997-10-01), Maruyama
patent: 704 487 (1965-02-01), None
Synthesis of 1,1,9,9-Tetrafluoro [2.2] Paracyclophane and Its Polymerization by Vapor Deposition Method, Takahito Itoh, Siro Okuoka, Masataka Kubo, and Shouji Iwatsuki, Journal of Polymer Science: Part A: Polymer Chemistry, vol. 33, 359-363 (1995).
Daisan Kasei Kabushiki Kaisha
Siegel Alan
Smith , Gambrell & Russell, LLP
LandOfFree
Dichloro tetraflouro-{2,2}-paracyclopane, a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Dichloro tetraflouro-{2,2}-paracyclopane, a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dichloro tetraflouro-{2,2}-paracyclopane, a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2582168