Patents Assigned to Spectra Group Limited, Inc.
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Publication number: 20150140537Abstract: A non-biological simulant liquid that includes about 30 to about 95 parts by weight of a polymer dispersion or a wax emulsion or dispersion, about 5 to about 70 parts by weight of a rheology modifying agent, and a pigment or a pigment combination. The non-biological simulant has a viscosity that is shear-dependent, such that the viscosity is from about 30 cP to about 300 cP at a shear rate from 0 s?1 to about 10 s?1, and such that the viscosity decreases when the shear rate increases. The pigment or pigment combination imbues the non-biological simulant with a color that approximates that of human or animal arterial or venous blood.Type: ApplicationFiled: November 18, 2014Publication date: May 21, 2015Applicant: Spectra Group Limited, Inc.Inventors: Oleg Grinevich, Igor L. Zheldakov, Puran Kumar De, Alexandre Mejiritski, Douglas C. Neckers
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Publication number: 20140306168Abstract: The present invention relates to compositions and processes for photoinitiating polymerization. Process for photoinitiating polymerization with ‘persulfate anion’ via photosensitized decomposition of persulfate anion with a composition that includes a light absorber, an electron transfer donor or acceptor, and a persulfate are described.Type: ApplicationFiled: April 12, 2013Publication date: October 16, 2014Applicant: SPECTRA GROUP LIMITED, INC.Inventors: Douglas C. Neckers, Puran K. De, Oleg Grinevich, Alex Mejiritski
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Patent number: 6586494Abstract: A radiation-curable inkjet composition for forming 3-D models or images comprising a semi-crystalline or crystalline, low-shrinkage, radiation-curable oligomeric material, a photoinitiator, and a diluent, said inkjet composition having a viscosity of between about 10 to about 50 cps at at least one temperature between 50 to 140° C.Type: GrantFiled: August 8, 2001Date of Patent: July 1, 2003Assignee: Spectra Group Limited, Inc.Inventors: Alexandre Mejiritski, Oleg V. Grinevich, Dustin B. Martin, Douglas C. Neckers
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Patent number: 6479217Abstract: A method for forming selectively colored printing plates using photosensitive recording elements is disclosed wherein the photosensitive recording element contains a photopolymerizable recording layer comprising a photopolymerizable monomer, a radical photoinitiator, a color former, and a color photoinitiator.Type: GrantFiled: February 22, 2001Date of Patent: November 12, 2002Assignee: Spectra Group Limited, Inc.Inventors: Oleg V. Grinevich, Alexander Mejiritski, Petr Serguievski, Douglas C. Neckers
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Patent number: 6433035Abstract: Selectively colorable compositions and a method for forming selectively colored polymeric bodies using such compositions are disclosed. In accordance with the invention, a selectively colorable polymerizable composition comprising a leucobase color former is irradiated with light of a particular wavelength and specific intensity for a specified duration. Exposure to actinic radiation cures the composition and activates the color former. Exposure to higher dosages of actinic radiation can bleach the composition. The irradiation dosage can be varied to selectively color the polymeric body whereby the resultant color of any particular area depends on the exposure dose received at that location. By varying the dose, a polymeric body can be prepared having distinctly colored elements at specific locations.Type: GrantFiled: August 14, 2000Date of Patent: August 13, 2002Assignee: Spectra Group Limited, Inc.Inventors: Oleg V. Grinevich, Douglas C. Neckers
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Patent number: 6309797Abstract: Selectively colorable polymerizable compositions and a method for forming selectively colored polymeric bodies using such compositions are disclosed. In accordance with the invention, a selectively colorable polymerizable composition comprising both a leucobase color former and a leuconitrile color former is irradiated with light of a particular wavelength and specific intensity for a specified duration. Exposure to actinic radiation cures the composition and activates the color formers. The irradiation dosage can be varied to selectively color the polymeric body whereby the resultant color of any particular area depends on the exposure dose received at that location. By varying the dose, a polymeric body can be prepared having distinctly colored elements at specific locations.Type: GrantFiled: April 26, 2000Date of Patent: October 30, 2001Assignee: Spectra Group Limited, Inc.Inventors: Oleg V. Grinevich, John H. Malpert, Alexandre Mejiritski, Douglas C. Neckers
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Patent number: 6211262Abstract: A corrosion resistant coating for metal surfaces curable with actinic radiation. The blend uses acrylate resin, photoinitiator and a corrosion preventing agent such as a metal surface passivator, overbased calcium sulfonate/calcium carbonate, a barrier pigment, or a combination of two or more of these agents.Type: GrantFiled: April 20, 1999Date of Patent: April 3, 2001Assignee: Spectra Group Limited, Inc.Inventors: Alexandre Mejiritski, Thomas Marino, Violeta Lungu, Dustin Martin, Douglas Neckers
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Patent number: 6200646Abstract: A method for precisely and efficiently creating three dimensional bodies, relief images or patterns, colored bodies, or a combination of these using photopolymers, photocolorizable polymers or photoresponsive coatings, in one irradiation step as disclosed. In particular this invention describes a method of generating objects or patterns with differential control of properties (depth, pore size, color, density, mechanical strength, hardness, degree of cross-linking, tackiness, etc.) such that the property varies across the xy array.Type: GrantFiled: August 25, 1999Date of Patent: March 13, 2001Assignee: Spectra Group Limited, Inc.Inventors: Douglas C. Neckers, Kathleen G. Specht, Oleg V. Grinevich, Alexandre Mejiritski
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Patent number: 6166233Abstract: The present invention relates to novel onium gallates or gallates of organometallic compounds and polymerizable compositions containing the same. The onium gallates include an anionic gallate moiety and a cationic moiety. The anionic gallate moiety has the formulaGaX.sub.a R.sub.b.sup.-in which X is a halogen or a hydroxy group, R is an aryl group, a and b represent integers ranging from 0 to 4 and the sum of a and b is 4. The cationic moiety is selected from the group consisting of iodonium, pyrylium, thiapyrylium, sulphonium, phosphonium, ferrocenium, and diazonium ions. The novel onium gallates are useful as cationic initiators of polymerization.Type: GrantFiled: August 17, 1999Date of Patent: December 26, 2000Assignee: Spectra Group Limited, Inc.Inventors: Douglas C. Neckers, Alexandre Mejiritski, John Malpert
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Patent number: 5998496Abstract: A compound of the general formula:A-L.sup.+ D.sup.-where A is a moiety which absorbs radiation and enters an excited state in which it accepts an electron; D.sup.- is a moiety which donates an electron to the excited state A and releases a free radical; and L.sup.+ is a cationic linking group which tethers electron acceptor moiety A to electron donor moiety D.sup.-. Cationic linking moiety L.sup.+ has the formula:-L'-G-where L' is a moiety which forms a stable radical with acceptor moiety A upon transfer of an electron from donor moiety D.sup.- to electron acceptor moiety A, and G is a moiety which forms a leaving group upon transfer of the electron from donor moiety D.sup.- to acceptor moiety A.Type: GrantFiled: August 19, 1996Date of Patent: December 7, 1999Assignee: Spectra Group Limited, Inc.Inventors: Salah A. Hassoon, Ananda M. Sarker, Douglas C. Neckers
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Patent number: 5955002Abstract: A method for monitoring a property of a cationically curable composition comprising the steps of: adding a fluorescence probe to a cationically curable composition; measuring the intensity of the fluorescence emission of the probe at a wavelength at which intensity changes in response to changes occurring in the composition, wherein the fluorescence probe is a compound of the formula (I): ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are the same or different and represent hydrogen, C.sub.1 -C.sub.20 alkyl, C.sub.1 -C.sub.20 alkoxyl, C.sub.2 -C.sub.20 alkenyl, C.sub.2 -C.sub.20 alkenoxyl, C.sub.3 -C.sub.27 cycloaliphatic, C.sub.7 -C.sub.27 aralkyl, C.sub.7 -C.sub.27 aralkoxyl, C.sub.7 -C.sub.27 alkaryl, or a substituted or unsubstituted diphenyl ether having the structure R.sup.9 --C.sub.6 H.sub.4 --O--C.sub.6 H.sub.4 R.sup.10 where R.sup.9 and R.sup.10 may be hydrogen, alkyl, aryl or aralkyl; and R.sup.1,R.sup.2 and R.sup.Type: GrantFiled: November 12, 1997Date of Patent: September 21, 1999Assignee: Spectra Group Limited, Inc.Inventors: Douglas C. Neckers, Kathleen G. Specht, Kesheng Feng, Roman Popielarz
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Patent number: 5942554Abstract: A method for the formation of a colored polymeric body which comprises subjecting a curable composition containing a color precursor and an onium salt to heat or actinic radiation to cure the composition, wherein the color precursor is converted to its colored form, and a curable composition capable of forming a colored polymeric body, are disclosed.Type: GrantFiled: February 20, 1996Date of Patent: August 24, 1999Assignee: Spectra Group Limited, Inc.Inventors: Yuijin Ren, Wolter Jager, Douglas C. Neckers
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Patent number: 5717217Abstract: A method for monitoring the properties of a coating comprising the steps of adding a fluorescence probe to a coating composition which has the ability to undergo microscopic changes in viscosity, the ratio of the intensity of the fluorescence emission of said probe at two wavelengths changing in response to said changes in said viscosity of said coating composition; curing said coating; causing said compound to fluoresce; measuring the fluorescence of said compound; calculating the ratio of the intensities of fluorescence emission of said compound at two or more wavelengths; relating said ratio to the monitored property of said coating.Type: GrantFiled: May 5, 1994Date of Patent: February 10, 1998Assignee: Spectra Group Limited, Inc.Inventors: Douglas C. Neckers, Jian Chang Song, Afranio Torres-Filho
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Patent number: 5677107Abstract: A method for producing a three-dimensional object having selected elements which are colored differently than other elements of the object comprising the steps of: (a) providing a film of a photohardenable composition containing a photoresponsive agent; (b) irradiating the film in a cross-sectional pattern of the object to be formed; (c) selectively irradiating one or more portions of the cross-sectional pattern corresponding to the selected elements which are desired to be colored differently with radiation which activates the photoresponsive agent, the photoresponsive agent thereby producing color in or removing color from the selected irradiated portions of the cross-sectional pattern; (d) repeating the steps a, b and c to form successive adjacent cross-sectional patterns of the object; and (e) integrating the cross-sectional patterns together to provide the object.Type: GrantFiled: May 6, 1996Date of Patent: October 14, 1997Assignee: Spectra Group Limited, Inc.Inventor: Douglas C. Neckers
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Patent number: 5639802Abstract: The present invention relates to a novel class of compounds which absorb light at wavelengths greater than 350 nm and are useful as fluorescers or as photoinitiators. The present invention provides compounds of the formulas (I) and (II) and their equivalents (the nomenclature of the compounds used herein is based on the numbering of positions as shown in formula (I)): ##STR1## where: when W is .dbd.O, W.sup.1 is hydrogen or --OR.sup.9 and when W is .dbd.NR.sup.+.sub.2, W is hydrogen or --NR.sub.2, A is hydrogen, alkenyl, alkyl or an election withdrawing group, and the remaining groups are as defined in the disclosure.Type: GrantFiled: November 23, 1993Date of Patent: June 17, 1997Assignee: Spectra Group Limited, Inc.Inventors: Douglas C. Neckers, Yubai Bi
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Patent number: 5623080Abstract: A compound of the formula (I) or (II): ##STR1## where R.sup.1, R.sup.2, R.sup.5 and R.sup.6 are the same or different and represent a hydrogen atom or a halogen atom and R.sup.1 and R.sup.2 may combine to form a ring; R.sup.3, and R.sup.4 are the same or different and represent a hydrogen atom, a halogen atom, a benzoyl group, a group of the formula --L(CH.sub.2).sub.n R.sup.8 where n is 1 to 8, R.sup.8 is a hydrogen, hydroxy, amino, dialkylamino, --COR.sup.16 or --COOR.sup.14 where R.sup.16 is a hydrogen, chlorine, COCl, C.sub.1 -C.sub.8 alkyl, --NR.sub.2 or aryl and R.sup.14 is a hydrogen, C.sub.1 -C.sub.8 alkyl, aryl, COR, 2,4-dinitrophenyl, N-imido or --NR.sub.2 and L is a direct bond or C.dbd.O; W is .dbd.O; W.sup.1 is hydrogen or --OR.sup.9, where R.sup.9 is hydrogen, C.sub.1 -C.sub.8 alkyl, acyl or a group of the formula --(CH.sub.2).sub.n R.sup.10 where n is 1 to 8 and R.sup.10 is amino, dialkylamino, hydroxy, acryloyl or methacryloyl; Y is oxygen, sulfur, selenium, tellurium, C.dbd.O, or >N--R.Type: GrantFiled: February 15, 1995Date of Patent: April 22, 1997Assignee: Spectra Group Limited, Inc.Inventors: Douglas C. Neckers, Jianmin Shi
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Method for determining thickness, degree of cure and other properties of a polymeric coating or film
Patent number: 5606171Abstract: A method for monitoring a property of a polymeric mass such as a coating or film comprising the steps of adding a fluorescence probe compound capable of fluorescing to a polymeric composition which has the ability to undergo changes in microviscosity, the ratio of the intensity of the fluorescence emission of said compound at two wavelengths changing in response to said changes in said microviscosity of said composition; curing said composition; causing said compound to fluoresce; measuring the fluorescence of said compound; calculating the ratio of the intensities of fluorescence emission of said compound at two or more wavelengths; relating said ratio to the monitored property of said composition.Type: GrantFiled: June 5, 1995Date of Patent: February 25, 1997Assignee: Spectra Group Limited, Inc.Inventors: Douglas C. Neckers, Jian C. Song, Afranio Torres-Filho, Wolter F. Jager, Zhijun J. Wang -
Patent number: 5514519Abstract: A method for producing a three-dimensional object having selected elements which are colored a different color than the color of other elements of the object, comprising the steps of:a. providing a film of a photohardenable composition containing a photoresponsive agent,b. irradiating the film in a cross-sectional pattern of the object to be formed so as to form hardened areas in the film.c. selectively irradiating one or more portions of the cross-sectional pattern corresponding to the selected elements which are desired to be colored a different color than the color of other elements of the object with radiation which activates the photoresponsive agent, the photoresponsive agent thereby producing color in or removing color from the selectively irradiated portions of the cross-sectional pattern, the steps being performed with radiation of a different wavelength than the radiation used in performing step b,d. repeating steps a, b and c to form successive adjacent cross-sectional patterns of the object, ande.Type: GrantFiled: April 7, 1994Date of Patent: May 7, 1996Assignee: Spectra Group Limited, Inc.Inventor: Douglas C. Neckers
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Patent number: 5451343Abstract: The present invention relates to a novel class of compounds which absorb light at wavelengths greater than 350 nm and are useful as fluorescers or as photoinitiators. The present invention provides compounds of the formulas (I) and (II) and their equivalents (the nomenclature of the compounds used herein is based on the numbering of positions as shown in formula (I)): ##STR1## where: when W is .dbd.O, W.sup.1 is hydrogen or --OR.sup.9 and when W is .dbd.NR.sup.+.sub.2, W is hydrogen or NR.sub.2.sup.+2, A is hydrogen, alkenyl, alkyl or an election withdrawing group, and the remaining groups are as defined in the disclosure.Type: GrantFiled: November 19, 1993Date of Patent: September 19, 1995Assignee: Spectra Group Limited, Inc.Inventors: Douglas C. Neckers, Jianmin Shi
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Patent number: 5395862Abstract: Disclosed is a photooxidizable initiator composition comprising a fluorone initiator and a coinitiator which is capable of accepting an electron from the fluorone upon excitation of the fluorone by actinic radiation, wherein the composition produces free radicals which initiate free radical reactions; and photohardenable compositions which comprise a free radical polymerizable compound, a fluorone initiator and a coinitiator capable of accepting an electron from the fluorone upon exposure of the composition to actinic radiation, and producing free radicals which initiate free radical polymerization.Type: GrantFiled: December 9, 1992Date of Patent: March 7, 1995Assignee: Spectra Group Limited, Inc.Inventors: Douglas C. Neckers, Jianmin Shi