US4381136A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for covering ultraviolet sources
Assignee: Roehm GmbH Darmstadt
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Filing: 1981-03-03
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Granted: 1983-04-26
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Expires: 2001-03-03
Abstract
Abstract Disclosed is a method for covering a source emitting ultraviolet radiation which method comprises covering said source with an acrylic glass colored with a coloring agent which absorbs in the visible region of the spectrum between 400 nanometers and 550 nanometers and exhibits an absorption of at least 2 percent for any wavelength within this region, and which agent concurrently has an average degree of transmission in the A- and B-region of the ultraviolet spectrum which is not below 55 percent and is not less than 10 percent at any wavelength in this region, said agent being present at a concentration equivalent to 0.0005 to 0.3 percent by weight in a layer, one millimeter thick, of a radiation absorbing matrix. Also disclosed are colored acrylic glass covers for use in such a method.
Inventors
- 👤 Ludwig Hosch
- 👤 Guenther Ittmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:15
CPC Classifications
A; A61; A61N; A61N5/00; A61N5/06; A61N5/0613; A61N5/0614; G; G02; G02B; G02B1/00; G02B1/10; G02B5/00; G02B5/20; G02B5/22; G02B5/223; A61N2005/0664; A61N2005/0667
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
117 words
A method for covering a source emitting ultraviolet radiation which comprises covering said source with an acrylic glass colored with a coloring agent which absorbs in the visible region of the spectrum between 400 nanometers and 550 nanometers and exhibits an absorption of at least 2 percent for a wavelength within this region, and which agent concurrently has an average degree of transmission in the A- and B-region of the ultraviolet spectrum which is not below 55 percent and is not less than 10 percent at any wavelength in this region, said agent being present at a concentration equivalent to 0.0005 to 0.3 percent by weight in a layer, one millimeter thick, of a radiation absorbing matrix.
Claim 2
Independent Claim
117 words
A method for covering a source emitting ultraviolet radiation which comprises covering said source with an acrylic glass colored with a coloring agent which absorbs in the visible region of the spectrum between 400 nanometers and 550 nanometers and exhibits an absorption of at least 2 percent for a wavelength within this region, and which agent concurrently has an average degree of transmission in the A- and B-region of the ultraviolet spectrum which is not below 55 percent and is not less than 10 percent at any wavelength in this region, said agent being present at a concentration equivalent to 0.0005 to 0.3 percent by weight in a layer, one millimeter thick, of a radiation absorbing matrix.
Claim 3
Dependent Claim
35 words
A method as in claim 1 wherein said agent has a degree of transmission of at least 20 percent at 300 nanometers and a degree of transmission of at least 50 percent at 320 nanometers.
Claim 4
Dependent Claim
23 words
A method as in claim 1 wherein said agent is a member selected from the group consisting of anthraquinone, azo, and chromium-complex dyestuffs.
Claim 5
Dependent Claim
32 words
A method as in claim 1 wherein said agent is present at a concentration equivalent to 0.003 to 0.1 percent by weight in a layer, one millimeter thick, of a radiation-absorbing matrix.
Claim 6
Dependent Claim
30 words
A method as in claim 1 wherein said agent absorbs radiation such that light from said covered source is experienced by the human eye as yellow to red in color.
Claim 7
Dependent Claim
16 words
A method as in claim 1 wherein said agent is present incorporated within said acrylic glass.
Claim 8
Dependent Claim
26 words
A method as in claim 6 wherein said acrylic glass additionally comprises at least one member selected from the group consisting of stabilizers and crosslinking agents.
Claim 9
Dependent Claim
12 words
A method as in claim 7 wherein said stabilizers are sterically-hindered amines.
Claim 10
Dependent Claim
13 words
A method as in claim 8 wherein said sterically-hindered amines are piperidine compounds.
Claim 11
Dependent Claim
17 words
A method as in claim 6 wherein said acrylic glass additionally comprises bis-(2,2,6,6-tetramethyl-4-piperidyl) sebacate as a stabilizer.
Claim 12
Dependent Claim
16 words
A method as in claim 1 wherein said acrylic glass is a polymer comprising methyl methacrylate.
Claim 13
Dependent Claim
19 words
A method as in claim 1 wherein said agent is present in a superficial layer in said acrylic glass.
Claim 14
Dependent Claim
23 words
A method as in claim 1 wherein said agent is present in a coating layer present on the surface of said acrylic glass.
Claim 15
Dependent Claim
20 words
A method as in claim 13 wherein said coating layer is a layer of lacquer present on said acrylic glass.
Claim 16
Dependent Claim
113 words
A cover for a source emitting ultraviolet radiation, said cover comprising an acrylic glass colored with a coloring agent which absorbs in the visible region of the spectrum between 400 nanometers and 550 nanometers and exhibits an absorption of at least 2 percent for a wavelength within this region, and which agent concurrently has an average degree of transmission in the A- and B-region of the ultraviolet spectrum which is not below 55 percent and is not less than 10 percent at any wavelength in this region, said agent being present at a concentration equivalent to 0.0005 to 0.3 percent by weight in a layer, one millimeter thick, of a radiation absorbing matrix.
Claim 17
Dependent Claim
113 words
A cover for a source emitting ultraviolet radiation, said cover comprising an acrylic glass colored with a coloring agent which absorbs in the visible region of the spectrum between 400 nanometers and 550 nanometers and exhibits an absorption of at least 2 percent for a wavelength within this region, and which agent concurrently has an average degree of transmission in the A- and B-region of the ultraviolet spectrum which is not below 55 percent and is not less than 10 percent at any wavelength in this region, said agent being present at a concentration equivalent to 0.0005 to 0.3 percent by weight in a layer, one millimeter thick, of a radiation absorbing matrix.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-04-25 | 1986-10-25 | 1987-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-04-25 | 1990-10-25 | 1991-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-04-25 | 1994-10-25 | 1995-04-26 | $7700.00 | Window Closed / Lapsed |