US4798445A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plastic optical fiber and process for producing the same
Assignee: Mitsubishi Chemical Corp
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Filing: 1986-04-03
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Granted: 1989-01-17
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Expires: 2006-04-03
Abstract
Abstract A plastic optical fiber which is superior in the light transmission characteristics, particularly in those within a visible light region and also superior in heat resistance, and a process for producing the same are provided, which plastic optical fiber comprises a polycarbonate as its core material and a polymer as its cladding material having a refractive index lower than that of the core material, wherein the relationship between the light transmission loss L500 (dB/km) of the fiber as measured at a wavelength of 500 nm and that as measured at 660 nm being expressed by the following inequality: L500<L660+4,000.
Inventors
- 👤 Takashi Yamamoto
- 👤 Katsuhiko Shimada
- 👤 Ryuji Murata
- 👤 Yasuteru Tahara
- 👤 Hiromu Terada
- 👤 Kenichi Sakunaga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:41
CPC Classifications
B; B29; B29D; B29D11/00; G; G02; G02B; G02B6/00; G02B6/02; G02B6/02033; B29C; B29C48/00; B29C48/03; B29C48/05; D; D01; D01D; D01D5/00; D01D5/28; D01D5/30; D01D5/34; D01F; D01F8/00; D01F8/04; D01F8/16; G02B1/00; G02B1/04; G02B1/045; G02B1/046; G02B6/04
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
124 words
A plastic optical fiber comprising polycarbonate as its core material and a polymer, as its cladding material, having a refractive index lower than that of the core material, which is formed by a melt-spinning step, wherein said core material of polycarbonate is supplied to the melt-spinning step in the form of a powder which has not been heated to a temperature exceeding its crystalline melting point at any step other than the melt-spinning step, wherein the relationship between light transmission loss, L 500 (dB/km), of said fiber as measured at a wavelength of 500 nm and light transmission loss, L 660 (dB/km), of said fiber measured at a wavelength of 660 nm is expressed by the following relation (I): L.sub.500 <L.sub.660 +4,000 dB/km (I).
Claim 2
Dependent Claim
124 words
A plastic optical fiber comprising polycarbonate as its core material and a polymer, as its cladding material, having a refractive index lower than that of the core material, which is formed by a melt-spinning step, wherein said core material of polycarbonate is supplied to the melt-spinning step in the form of a powder which has not been heated to a temperature exceeding its crystalline melting point at any step other than the melt-spinning step, wherein the relationship between light transmission loss, L 500 (dB/km), of said fiber as measured at a wavelength of 500 nm and light transmission loss, L 660 (dB/km), of said fiber measured at a wavelength of 660 nm is expressed by the following relation (I): L.sub.500 <L.sub.660 +4,000 dB/km (I).
Claim 3
Dependent Claim
17 words
A plastic optical fiber according to claim 1, wherein said L 660 is 1,000 dB/km or less.
Claim 4
Dependent Claim
32 words
A plastic optical fiber according to claim 1, wherein said polycarbonate as the core material has an intrinsic viscosity of 0.3 to 0.6 dl/g as measured in methylene chloride at 20° C.
Claim 5
Dependent Claim
43 words
A plastic optical fiber according to claim 1, wherein said polymer as the cladding material is a fluorine-containing polymer, and said fiber has outside the cladding, a protection layer composed of a polycarbonate having a heat deformation temperature of 100° C. or higher.
Claim 6
Dependent Claim
69 words
A plastic optical fiber according to claim 1, wherein said polymer as the cladding material is a polymer having as its main component, at least one of the repetition units expressed by the following formula (II): ##STR6## wherein R represents an alkyl group of 1 to 5 carbon atoms, a fluorinated alkyl group of 1 to 5 carbon atoms or a cycloalkyl group of 3 to 6 carbon atoms.
Claim 7
Dependent Claim
53 words
A plastic optical fiber according to claim 5, wherein the melt flow rate [MFR] 1 of said core material and the melt flow rate [MFR] 2 of said cladding material have relationships expressed by the following inequalities [III] and [IV]: 3 g/10 min.≧[MFR].sub.1 ≦30 g/10 min. [III] [MFR].sub.1 ≦[MFR].sub.2 ≦40 g/10 min. [IV]
Claim 8
Dependent Claim
32 words
A plastic optical fiber according to claim 1, wherein said fiber has outside the cladding, a protection layer composed of a polycarbonate having a heat deformation temperature of 125° C. or higher.
Claim 9
Dependent Claim
27 words
A plastic optical fiber according to claim 7, wherein said fiber has outside the protection layer, a coating layer composed of a plastic having a silane-crosslinked structure.
Claim 10
Dependent Claim
45 words
A plastic optical fiber according to claim 8, wherein said silane-crosslinked structure is composed of --Si--O--Si--, and said plastic is composed of an organic polymer selected from the group consisting of polyethylene, chlorinated polyethylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-ethylacrylate copolymer and tetrafluorinated ethylene-propylene copolymer.
Claim 11
Dependent Claim
33 words
A plastic optical fiber according to claim 1, wherein said fiber has outside the cladding, a protection layer composed of an organic polymer having a flexural modulus of 5,000 Kg/cm 2 or less.
Claim 12
Dependent Claim
27 words
A plastic optical fiber according to claim 10, wherein said fiber has outside the protection layer, a coating layer composed of a plastic having a silane-crosslinked structure.
Claim 13
Dependent Claim
99 words
A process for producing a plastic optical fiber by a melt-spinning step, wherein polycarbonate is used as the core material of the fiber and a polymer having a refractive index lower than that of the core material is used as the cladding material thereof; wherein the core material of polycarbonate is supplied to the melt-spinning step in the form of a powder which has not been heated to a temperature exceeding its crystalline melting point at any preceding step other than the melt-spinning step, and then, melted at a temperature exceeding its crystalline melting point in the melt-spinning step.
Claim 14
Dependent Claim
99 words
A process for producing a plastic optical fiber by a melt-spinning step, wherein polycarbonate is used as the core material of the fiber and a polymer having a refractive index lower than that of the core material is used as the cladding material thereof; wherein the core material of polycarbonate is supplied to the melt-spinning step in the form of a powder which has not been heated to a temperature exceeding its crystalline melting point at any preceding step other than the melt-spinning step, and then, melted at a temperature exceeding its crystalline melting point in the melt-spinning step.
Claim 15
Dependent Claim
63 words
The process of claim 12, wherein said polycarbonate is melted at a temperature exceeding its crystalline melting point in a melt-extruder and extruded from a spinning nozzle either (i) after cooling to a temperature between 200° C. and the crystalline melting temperature of said polycarbonate or (ii) while cooling to a temperature between 200° C. and the crystalline melting temperature of said polycarbonate.
References Cited (Backward Citations)
US3993834A
Cited
US4161500A
Cited
US4334733A
Cited
EP0098578A1
Cited
JPS5975202A
Cited
EP0126428A2
Cited
EP0128517A2
Cited
EP0128516A1
Cited
JPS6021012A
Cited
JPS6032004A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-01-17 | 1992-07-18 | 1993-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-17 | 1996-07-18 | 1997-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-17 | 2000-07-18 | 2001-01-17 | $7700.00 | Window Closed / Lapsed |