← Back to Patent Explorer
US4167490A Expired / Lapsed US ⏱️ 0.0 years remaining

Flexible ultraviolet radiation transmitting filters

Assignee: EIDP Inc
•
Filing: 1975-12-22
•
Granted: 1979-09-11
•
Expires: 1995-12-22
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Flexible filters capable of transmitting radiation in the spectral range of 315 to 380 nm and absorbing radiation in the spectral range of 400 to 550 nm consist essentially of a thin flexible film, e.g., polyethylene terephthalate containing or having coated thereon a dye in a concentration of 15 to 60 mg/dm 2 and optionally, as a component of the coating, a thermoplastic organic binder, e.g., cellulose acetate butyrate, present in the coating with the dye, said dye being of the formula: ##STR1## where R 1 is lower alkyl of 1 to 5 carbon atoms; R 2 and R 3 , which may be the same or different, are selected from the group consisting of R 1 , 2-cyanoethyl, 2-hydroxyethyl and ##STR2## or form a saturated 5- or 6- membered ring; R 4 is taken from the class consisting of lower alkyl of 1 to 5 carbon atoms, aryl or alkaryl of 6 to 9 carbon atoms, and aralkyl. The filters are useful in exposing dual response photosensitive materials with ultraviolet radiation sources which contain appreciable quantities of visible radiation.

Inventors

  • 👤 Catharine E. Looney

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 19:01
CPC Classifications
F; F21; F21V; F21V9/00; B; B29; B29D; B29D11/00; B29D11/00634; G; G02; G02B; G02B1/00; G02B1/04; G02B5/00; G02B5/20; G02B5/22; G02B5/223; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31786

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 158 words
A flexible filter capable of transmitting radiation in the spectral range between 315 and 380 nm and absorbing radiation strongly in the spectral range between 400 to 550 nm maximally absorbing in the spectral range between 440 to 500 nm, consisting essentially of a thin flexible film substantially transparent to radiation in the spectral range between 315 and 380 nm having homogeneously added thereto a dye in a concentration of 15 to 60 mg/dm 2 of the formula: ##STR12## where R 1 is lower alkyl of 1 to 5 carbon atoms; R 2 and R 3 , which may be the same or different, are selected from the group consisting of R 1 , 2-cyanoethyl, 2-hydroxyethyl and ##STR13## or from a saturated 5- or 6-membered ring; R 4 is taken from the class consisting of lower alkyl of 1 to 5 carbon atoms, aryl of 6 carbon atoms or alkaryl of 7 to 9 carbon atoms, and arakyl.
Claim 2
Dependent Claim 158 words
A flexible filter capable of transmitting radiation in the spectral range between 315 and 380 nm and absorbing radiation strongly in the spectral range between 400 to 550 nm maximally absorbing in the spectral range between 440 to 500 nm, consisting essentially of a thin flexible film substantially transparent to radiation in the spectral range between 315 and 380 nm having homogeneously added thereto a dye in a concentration of 15 to 60 mg/dm 2 of the formula: ##STR12## where R 1 is lower alkyl of 1 to 5 carbon atoms; R 2 and R 3 , which may be the same or different, are selected from the group consisting of R 1 , 2-cyanoethyl, 2-hydroxyethyl and ##STR13## or from a saturated 5- or 6-membered ring; R 4 is taken from the class consisting of lower alkyl of 1 to 5 carbon atoms, aryl of 6 carbon atoms or alkaryl of 7 to 9 carbon atoms, and arakyl.
Claim 3
Dependent Claim 15 words
A filter according to claim 1 wherein the dye is homogeneously present in the film.
Claim 4
Dependent Claim 15 words
A filter according to claim 1 wherein the film bears a layer of the dye.
Claim 5
Dependent Claim 18 words
A filter according to claim 3 wherein a macromolecular thermoplastic organic binder is present in the dye layer.
Claim 6
Dependent Claim 27 words
A filter according to claim 4 wherein the dye and binder are present in the layer in the weight range of 180 to 220 mg/dm 2 .
Claim 7
Dependent Claim 13 words
A filter according to claim 5 wherein the binder is cellulose acetate butyrate.
Claim 8
Dependent Claim 14 words
A filter according to claim 1 wherein the dye is of the formula ##STR14##
Claim 9
Dependent Claim 13 words
A filter according to claim 1 wherein the flexible film is polyethylene terephthalate.
Claim 10
Dependent Claim 18 words
A filter according to claim 3 wherein the dye layer bears a thin flexible ultraviolet radiation transparent film.
Claim 11
Dependent Claim 73 words
A flexible filter capable of transmitting radiation in the spectral range between 315 to 380 nm and absorbing radiation in the spectral range between 400 to 550 nm consisting essentially of (a) a resin-subbed biaxially oriented polyethylene terephthalate film, 0.1 to 0.175 mm thick, coated with a homogeneous mixture, 200±20 mg/dm 2 of (b) a dye of the formula: ##STR15## in an amount of 30±3 mg/dm 2 , and (c) cellulose acetate butyrate.
Claim 12
Dependent Claim 73 words
A flexible filter capable of transmitting radiation in the spectral range between 315 to 380 nm and absorbing radiation in the spectral range between 400 to 550 nm consisting essentially of (a) a resin-subbed biaxially oriented polyethylene terephthalate film, 0.1 to 0.175 mm thick, coated with a homogeneous mixture, 200±20 mg/dm 2 of (b) a dye of the formula: ##STR15## in an amount of 30±3 mg/dm 2 , and (c) cellulose acetate butyrate.

References Cited (Backward Citations)

US2627088A Cited
US2779684A Cited
US2803640A Cited
US3390996A Cited
US3382183A Cited
US3390994A Cited
US3813255A Cited
US3874876A Cited
US3918976A Cited
US3914024A Cited
US3906510A Cited
US3984246A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-09-10 1983-03-12 1983-09-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-09-10 1987-03-12 1987-09-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-09-10 1991-03-12 1991-09-11 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag