Optical Radiation Corporation

Cyprus Mines Corporation

Amoco Corporation

Lockheed Corporation

Cyprus Minerals Company

Other

Ecca Calcium Products, Inc.

Kenneth E Weber

Edwin A Creasman

Thomas R Paul

David R Navarrete

Jimmy D McCullough

Jerry W Rayfield

Dirk Oberlin

Scott Chang

Mei-Ing Cheng

Robert A Baker

Richard Seyb Lamar

William E Pratt

Robert Baker

Churchai T Soodjinda

Robert E Roeder

Steven D Hoffer

Alisa K Rogers

A process for forming an intraocular lens with haptics having high fracture toughness mixing solid particles with an uncured polymer matrix and introducing the uncured mixture into a mold. Ultrasonic energy is then applied to the mold until the uncured mixture begins to solidify. Sufficient heat is then applied to the polymer mixture to completely cure the polymer. The cured polymer which will form the haptics, is then removed from the mold and a hole for forming the optic is formed in the cured polymer. An uncured polymer matrix suitable for use, when cured, as an optic, is then introduced into the hole and cured. An intraocular lens is then machined from the resulting cured composition.

Process for forming intraocular lenses having haptics with high fracture

In a method of producing an intraocular lens having a substantially clear optic and at least one filamentous haptic having high fracture toughness, solid particles are mixed into an uncured polymer, and the mixture is inserted into a mold. Ultrasonic energy is applied to the mold until the mixture solidifies. Heat is applied to complete the curing process. Ultrasonic energy is also preferably applied to the particles and uncured polymer mixture to improve dispersion of the particles therein.

Method of producing haptics for intraocular lenses having high fracture

An intraocular lens comprises a substantially clear optic and at least one filamentous haptic having high fracture toughness. The haptic is formed of a polymer composition comprising low concentrations of solid particles uniformly dispersed throughout a polymer matrix.

Haptics for intraocular lenses having high fracture toughness

A method of and substances for reducing pitch in pulping and papermaking operations, particularly in furnishes made by mechanical pulping processes containing wood pulp in amounts greater than about 10% by weight, are disclosed. The method comprises adding to a pitch-containing furnish a stable, water dispersible particulate composite substance prepared by irreversibly adsorbing a water soluble cationic polymer, e.g., a poly(diallyldimethylammonium chloride), onto an essentially water insoluble particulate substrate, e.g., kaolin, thereby rendering the cationic polymer insoluble and immobile, the cationic polymer being sufficiently electropositive so that the particulate composite pitch control substance exhibits a zeta potential of at least about +30 mV, and preferably from about +60 mV to about +80 mV, the amount of the composite substance added to the furnish being effective to finely disperse pitch for removal as finely-dispersed pitch-containing aggregates in a paper sheet produced from said furnish. Further improvements in pitch control can be achieved using these particulate composite pitch control substances together with alum and/or relatively high molecular weight alkylene oxide polymers, and other desirable effects, including improved fines retention, better drainage and lower waste treatment costs are also obtained when practicing this method.

Method of reducing pitch in pulping and papermaking operations

Means are disclosed for rendering talcs such as Montana talc or like talcs hitherto considered incompatible or unsuitable as fillers for thermoplastic resinous compositions, and particularly polypropylene molding resins, suitable for this use. Such talcs, which in their unbeneficiated state strongly discolor the resinous matrix and affect its long-term heat stability, are beneficiated in accordance with this invention, generally at low cost, while improving or at least not unacceptably diminishing other significant physical properties, particularly yellowness index, flexural modulus and impact strength, of the resulting molded article. This is accomplished by admixing Montana talc or the like with an effective amount of a combination of:

Beneficiated talcs

Means are disclosed for rendering talcs such as Chinese talcs, Austrialian talcs, Italian talcs or like talcs which, when ground to an approximately 2.5-5.0 .mu.m median particle size, exhibit a wet powder brightness of at least about 30% and which have hitherto been considered acceptable as fillers for thermoplastic resinous compositions, and particularly polypropylene molding resins, even suitable for this use. Such talcs are beneficiated in accordance with this invention, generally at low cost, to further enhance brightness, heat stability or both these properties in thermoplastic molded articles filled with these beneficiated acceptable talcs, while also improving or at least not unacceptably diminishing other significant physical properties, particularly tensile properties, of the resulting molded article. This is accomplished by admixing the Chinese, Australian or Italian talc, or the like, with an effective amount of a combination of:

Novel finely divided particulate calcium carbonate compositions comprising mixtures of a preponderance of dry ground calcium carbonate with a smaller amount of wet ground calcium carbonate, each of these components having particular particle size characteristics and particle size distributions, are disclosed. When used as all or part of the filler in thermosetting and thermoplastic resinous compositions, e.g., thermosetting polyester resinous molding compositions, paints and other finishes, sealants and the like, such mixtures provide compositions having high filler loadings coupled with acceptably low viscosities and better processability than resinous compositions containing all dry-ground fillers.

Dry ground/wet ground calcium carbonate filler compositions

Novel finely divided particulate calcium carbonate compositions comprising mixtures of a preponderance of dry ground calcium carbonate with a smaller amount of wet ground calcium carbonate, each of these components having particular particle size characteristics and particle size distributions, are disclosed. When used as all or part of the filler in thermosetting and thermosplastic resinous compositions, e.g., thermosetting polyester resinous molding compositions, paints and other finishes, sealants and the like, such mixtures provide compositions having high filler loadings coupled with acceptably low viscosities and better processability than resinous compositions containing all dry-ground fillers.

Means are disclosed for rendering talcs such as Chinese talcs, Australian talcs, Italian talcs or like talcs which, when ground to an approximately 2.5-5.0 .mu.m median particle size, exhibit a wet powder brightness of at least about 30% and which have hitherto been considered acceptable as fillers for thermoplastic resinous compositions, and particularly polypropylene molding resins, even suitable for this use. Such talcs are beneficiated in accordance with this invention, generally at low cost, to further enhance brightness, heat stability or both these properties in thermoplastic molded articles filled with these beneficiated acceptable talcs, while also improving or at least not unacceptably diminishing other significant physical properties, particularly tensile properties, of the resulting molded article. This is accomplished by admixing the Chinese, Australian or Italian talc, or the like, with an effective amount of a combination of:

A rubber composition containing carbon black as a reinforcing filler and a quaternary ammonium salt as a coupling agent and a method of making it are disclosed.

Rubber composition and method of incorporating carbon black and a

A rubber composition containing carbon black and a second particulate filler of kaolin, metakaolin, talc, pyrophyllite coal, coke, graphite or metal carbonate filler and a method of making it are disclosed.

Rubber composition and method

A modified alkaline peroxide pre-bond process for the surface treatment of titanium is useful as a practical production process. In this modified process, an exceptionally wide range of allowable peroxide concentration, namely, from 0.001 molar to 0.2 molar (and preferably 0.001 molar to 0.01 molar) may be tolerated and a novel real-time peroxide monitoring and control technique is employed. The process is further improved by means of the use of stabilizers such as precipitated magnesium silicate which greatly increases bath life-time and reduces the overall operating cost of the process. Solution operating conditions have been defined which permit titanium adherends to be processed satisfactorily over a wide range of hydrogen peroxide concentration. In particular, the acceptable temperature range is 125.degree. F.-165.degree. F. (51.7.degree. C.-73.8.degree. C.); the treatment period is 15 to 25 minutes and the hydroxide concentration is 0.3 to 0.9 molar. The preferred values are approximately 145.degree. F. (62.7.degree. C.); 20 minutes, and 0.5 molar, respectively. An electrochemical method has been established utilizing a magnesium electrode (114) which provides a stable potential characteristic that is dependent only on the concentration of the peroxide. The resultant capability to reliably monitor the peroxide concentration in real time in turn permits an automated feed system to be effectively utilized for sustaining the peroxide concentration within the desired limits.

Apparatus for maintaining peroxide concentration

A modified alkaline peroxide pre-bond process for the surface treatment of titanium is useful as a practical production process. In this modified process, an exceptionally wide range of allowable peroxide concentration, namely, from 0.001 molar to 0.2 molar (and preferably 0.001 molar to 0.01 molar) may be tolerated and a novel real-time peroxide monitoring and control technique is employed. The process is further improved by means of the use of stabilizers such as precipitated magnesium silicate which greatly increases bath life-time and reduces the overall operating cost of the process. Solution operating conditions have been defined which permit titanium adherends to be processed satisfactorily over a wide range of hydrogen peroxide concentration. In particular, the acceptance temperature range is 125.degree. F.-165.degree. F. (51.7.degree. C.-73.8.degree. C.); the treatment period is 15 to 25 minutes and the hydroxide concentration is 0.3 to 0.9 molar. The preferred values are approximately 145.degree. F. (62.7.degree. C.); 20 minutes, and 0.5 molar, respectively. An electromechanical method has been established utilizing a magnesium electrode (114) which provides a stable potential characteristic that is dependent only on the concentration of the peroxide. The resultant capability to reliably monitor the peroxide concentration in real time in turn permits an automated feed system to be effectively utilized for sustaining the peroxide concentration within the desired limits.

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Pacific Palisades, CA, United States of America

Kenneth E Weber