Patents Assigned to Spectra Group Limited, Inc.
  • Publication number: 20150140537
    Abstract: 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: Application
    Filed: November 18, 2014
    Publication date: May 21, 2015
    Applicant: Spectra Group Limited, Inc.
    Inventors: Oleg Grinevich, Igor L. Zheldakov, Puran Kumar De, Alexandre Mejiritski, Douglas C. Neckers
  • Publication number: 20140306168
    Abstract: 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: Application
    Filed: April 12, 2013
    Publication date: October 16, 2014
    Applicant: SPECTRA GROUP LIMITED, INC.
    Inventors: Douglas C. Neckers, Puran K. De, Oleg Grinevich, Alex Mejiritski
  • Patent number: 6586494
    Abstract: 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: Grant
    Filed: August 8, 2001
    Date of Patent: July 1, 2003
    Assignee: Spectra Group Limited, Inc.
    Inventors: Alexandre Mejiritski, Oleg V. Grinevich, Dustin B. Martin, Douglas C. Neckers
  • Patent number: 6479217
    Abstract: 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: Grant
    Filed: February 22, 2001
    Date of Patent: November 12, 2002
    Assignee: Spectra Group Limited, Inc.
    Inventors: Oleg V. Grinevich, Alexander Mejiritski, Petr Serguievski, Douglas C. Neckers
  • Patent number: 6433035
    Abstract: 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: Grant
    Filed: August 14, 2000
    Date of Patent: August 13, 2002
    Assignee: Spectra Group Limited, Inc.
    Inventors: Oleg V. Grinevich, Douglas C. Neckers
  • Patent number: 6309797
    Abstract: 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: Grant
    Filed: April 26, 2000
    Date of Patent: October 30, 2001
    Assignee: Spectra Group Limited, Inc.
    Inventors: Oleg V. Grinevich, John H. Malpert, Alexandre Mejiritski, Douglas C. Neckers
  • Patent number: 6211262
    Abstract: 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: Grant
    Filed: April 20, 1999
    Date of Patent: April 3, 2001
    Assignee: Spectra Group Limited, Inc.
    Inventors: Alexandre Mejiritski, Thomas Marino, Violeta Lungu, Dustin Martin, Douglas Neckers
  • Patent number: 6200646
    Abstract: 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: Grant
    Filed: August 25, 1999
    Date of Patent: March 13, 2001
    Assignee: Spectra Group Limited, Inc.
    Inventors: Douglas C. Neckers, Kathleen G. Specht, Oleg V. Grinevich, Alexandre Mejiritski
  • Patent number: 6166233
    Abstract: 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: Grant
    Filed: August 17, 1999
    Date of Patent: December 26, 2000
    Assignee: Spectra Group Limited, Inc.
    Inventors: Douglas C. Neckers, Alexandre Mejiritski, John Malpert
  • Patent number: 5998496
    Abstract: 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: Grant
    Filed: August 19, 1996
    Date of Patent: December 7, 1999
    Assignee: Spectra Group Limited, Inc.
    Inventors: Salah A. Hassoon, Ananda M. Sarker, Douglas C. Neckers
  • Patent number: 5955002
    Abstract: 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: Grant
    Filed: November 12, 1997
    Date of Patent: September 21, 1999
    Assignee: Spectra Group Limited, Inc.
    Inventors: Douglas C. Neckers, Kathleen G. Specht, Kesheng Feng, Roman Popielarz
  • Patent number: 5942554
    Abstract: 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: Grant
    Filed: February 20, 1996
    Date of Patent: August 24, 1999
    Assignee: Spectra Group Limited, Inc.
    Inventors: Yuijin Ren, Wolter Jager, Douglas C. Neckers
  • Patent number: 5717217
    Abstract: 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: Grant
    Filed: May 5, 1994
    Date of Patent: February 10, 1998
    Assignee: Spectra Group Limited, Inc.
    Inventors: Douglas C. Neckers, Jian Chang Song, Afranio Torres-Filho
  • Patent number: 5677107
    Abstract: 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: Grant
    Filed: May 6, 1996
    Date of Patent: October 14, 1997
    Assignee: Spectra Group Limited, Inc.
    Inventor: Douglas C. Neckers
  • Patent number: 5639802
    Abstract: 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: Grant
    Filed: November 23, 1993
    Date of Patent: June 17, 1997
    Assignee: Spectra Group Limited, Inc.
    Inventors: Douglas C. Neckers, Yubai Bi
  • Patent number: 5623080
    Abstract: 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: Grant
    Filed: February 15, 1995
    Date of Patent: April 22, 1997
    Assignee: Spectra Group Limited, Inc.
    Inventors: Douglas C. Neckers, Jianmin Shi
  • Patent number: 5606171
    Abstract: 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: Grant
    Filed: June 5, 1995
    Date of Patent: February 25, 1997
    Assignee: Spectra Group Limited, Inc.
    Inventors: Douglas C. Neckers, Jian C. Song, Afranio Torres-Filho, Wolter F. Jager, Zhijun J. Wang
  • Patent number: 5514519
    Abstract: 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: Grant
    Filed: April 7, 1994
    Date of Patent: May 7, 1996
    Assignee: Spectra Group Limited, Inc.
    Inventor: Douglas C. Neckers
  • Patent number: 5451343
    Abstract: 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: Grant
    Filed: November 19, 1993
    Date of Patent: September 19, 1995
    Assignee: Spectra Group Limited, Inc.
    Inventors: Douglas C. Neckers, Jianmin Shi
  • Patent number: 5395862
    Abstract: 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: Grant
    Filed: December 9, 1992
    Date of Patent: March 7, 1995
    Assignee: Spectra Group Limited, Inc.
    Inventors: Douglas C. Neckers, Jianmin Shi