Abstract: This invention relates to a method and a device for agglomerating particles in a gaseous flow through an acoustical agglomeration chamber (3). According to the invention a portion of the flow at the outlet of the chamber is selectively extracted by preferring larger particles, and is re-injected into the inlet of the chamber.

Abstract: A vacuum cleaner exhaust filter assembly includes a main HEPA exhaust filter, and an ion generation stage to add ions to the air. The ion generation stage preferably is a polypropylene mesh which generates ions through static electric interaction with the moving air as the result of friction. The exhaust filter assembly preferably also includes a pre-filter impregnated with carbon, preferably in the form of activated charcoal, to absorb odors from the exhaust air. The filter components, arranged in the preferred order, are the carbon pre-filter, the main HEPA exhaust filter, and the ion generation mesh.

Abstract: A method of separating liquid drops from a gas stream includes the step of introducing the gas stream having a temperature greater than 600.degree. C. into shaped elements having very narrow channels through which the gas stream flows, wherein the shaped elements are of a material that becomes conductive at high temperatures and further includes the step of selecting the width of the narrow channels based on the gas stream velocity such that turbulence is generated along the flow path causing the liquid drops to strike the channel walls and deposit thereon. The apparatus for separating liquid drops from a gas stream includes a plurality of shaped elements having very narrow channels through which the gas stream having a temperature greater than 600.degree. C.

Abstract: Apparatus and method for separating carbon particles from flyash includes one of increasing a relative humidity of the flyash or decreasing the relative humidity of the flyash to within an optimum humidity range, and introducing the flyash within the optimum humidity range into a triboelectric separator so as to triboelectrically charge the carbon particles and the flyash and so as to electrostatically separate the charged carbon particles from the charged flyash.

Abstract: A frameless electrostatic air filter used in heating and air conditioning systems includes a plurality of filter media layers and an internal support grill and has no external support grill or frame. The frameless electrostatic air filter has an internal support grill to support the filter media layers and a fabric edging that is secured in place all the way around the edge of the frameless electrostatic air filter. The center of the frameless electrostatic air filter is secured with a plastic rivet. The frameless electrostatic air filter seats and seals tight to the inside lip of filter receptacles.

Abstract: A frameless electrostatic air filter used in heating and air conditioning systems includes a plurality of filter media layers and an internal support grill and has no external support grill or frame. The frameless electrostatic air filter has an internal support grill to support the filter media layers and a fabric edging that is secured in place all the way around the edge of the frameless electrostatic air filter. The center of the frameless electrostatic air filter is secured with a plastic rivet. The frameless electrostatic air filter seats and seals tight to the inside lip of filter receptacles.

Abstract: A filter apparatus for use in a forced air ventilation system, the filter apparatus having a first fan folded sheet of a washable first type of filter material, a second fan folded sheet of a second type of filter material, and fanfolds of the first and second fan folded sheets are substantially equally shaped and folded together such that the fanfolds of the first and second fan folded sheets are interdigitated to form a filter material assembly. The first type of filter material is preferably an electrostatically self-charging washable material such as woven polypropylene and the second type of filter material is preferably disposable and contains activated charcoal. The filter material assembly may be removably disposed in a rectangular filter frame for mounting the filter material assembly in the forced air system. The filter frame has at least one crank shaft rotatably deposed between two opposed side walls which are between an open front end and an open back end of the frame.

Abstract: A triboelectrostatic separation apparatus includes a mixing chamber having opposed first and second charging ports, a separator having a separation chamber, first and second electrodes, and a variable voltage source for applying respective positive and negative voltage potentials to the electrodes. First and second particle streams are delivered through the first and second charging ports resulting in the impingement of the particle streams upon each other within the mixing chamber, thus enhancing the electrostatic charging of the particles contained within the particle streams. The apparatus may also include a pre-separator having a pre-separation chamber, a charged particle collection chamber and a plurality of feed passageways providing fluid communication between the pre-separation and the charged particle collection chambers.

Abstract: An electrostatic supercharger screen (10) is within an air flow duct (12) in front of a standard air filter (14), between a furnace/cooling unit (16) and an air vent grill (18) in a wall (20) of a building (22). The screen (10) includes an element (24) for removing small microns of particles in air that goes past the standard air filter (14) within the air flow duct (12), so as to help clean the air of pollens, smoke, odors and bacteria. A structure (26) is for supporting the removing element (24) parallel to the standard air filter (14). A component (28) is for confining the removing element (24) and the supporting structure (26) in a juxtaposed relationship.

Abstract: An apparatus for reducing electrostatic charge of particles in a waste container. In one embodiment the waste container is coated with a liquid having a viscosity sufficient to prevent tribocharging between the waste container and the waster toner particles, and to collect toner particles deposited from the cyclone separator into the waste container. Another embodiment describes the use of a flange extending into the waste container to prevent tribocharging that can cause explosions in the waste toner bottle.

Abstract: A method is provided for specifying and altering the electrical properties of fibers and fabrics. This allows the prescription of filter media prepared from these constituents for consistently optimum or near optimum performance in the collection of particulate matter. The method may include the steps of determining the triboelectric properties of fabrics having other desirable filter media characteristics, modifying the triboelectric properties of these fabrics as needed to preferentially selected properties and utilizing, selectively, modified fabrics as the filter medium for optimally attracting gas entrained electrically charged particles to the surface of the filter. The modification of the triboelectric properties may be realized chemically or by dyeing the fibers and fabric.

Abstract: An apparatus and method for reducing the amount of unburned carbon in raw flyash, wherein raw flyash containing unburned carbon is introduced into the tribocharger, the tribocharger producing positive and negative surface charges on the respective particles of carbon and flyash, introducing the charged particles into an electrical field containing positively and negatively charged plates, the positively and negatively charged particles being collected on the negatively and positively charged plates, and selectively vibrating the plates to selectively recover the unburned carbon and flyash.

Abstract: An insert for air flow ducts includes a band (10) of a semi-stiff, although flexible character, a plurality of interspaced interflanges (11) along the band and spaced edge flanges (14) which are connected with the interflanges, the interflanges in pairs together with the band (10) and the edge flanges (14) delimiting consecutive cavities or pipes (12') along the band, the opposed ends of the cavities or pipes being open, the band being formed into a loop in which the band and the edge flanges are located tightly adjacent to each other and in which the pipes (12') are substantially evenly distributed.

Abstract: A vent assembly useful for venting bags containing radioactive waste material includes a base plate with a chamber projecting therefrom and a cap plate which has a center portion that snap fits over the chamber. The base plate and cap plate have flange portions which overlie the inner and outer surfaces of the bag to secure the vent to the bag by clamping against the wall of the bag. A ring is snap fitted into the chamber prior to snap fitting the cap plate to the base plate and a compressible mass of fibrous filter material is contained within the ring. The filter material may be selected from a number of filter materials such as spun polyester, activated carbon felt, fibrous cellulose or sintered stainless steel fibers. Preferably, the filter material is electrically charged, fibrous polymer material.

Abstract: A particle separating arrangement includes a filter tube (1) that is made of electrostatically chargeable fibres, for instance electrete fibres, and through which an axial air stream can pass radially in a direction from within outwardly. Within the tube (1) an insert (2) is placed, including a carrier (3) which extends transversely to the tube, the carrier having a plurality of strip elements (4) arranged to be set in motion by the passing air stream and thereby be rubbed against each other in order to produce an electrostatically charged field in their environs. This field is used to automatically and continuously keep the chargeable fibres in the filter tube wall (1) electrostatically charged.

Abstract: A filter medium having high stiffness is provided. The filter is a nonwoven web of conjugate fibers which has a Frazier permeability above 200 CFM, an NaCl efficiency above 75 percent, a Gurley Stiffness above 700 mg, and a SEP value of above 80. The conjugate fibers may be polyolefin, more particularly polypropylene and polyethylene in a side-by-side configuration. The medium may be made into a filter by conventional means such as pleating. Such filters are useful in HVAC systems and transportation cabin air filtration.

Abstract: A filter apparatus for mounting over an opening at an end of a forced air system duct has a filter frame with sidewalls between open front and back ends and a channel which opens inwardly of the sidewalls. At the front end is a sheet of preferably self charging electrostatic washable filter material behind a grill, both of which are peripherally disposed within the channel and are sized and sufficiently flexible so as to be removably insertable into the channel. A second sheet of a second filter material, preferably including activated charcoal, may be disposed in the channel behind the first sheet of filter material. The filter material may be made of a woven polypropylene and the sheet may have heat sealed finished edges. A wall mount having a support frame for mounting on a wall around the opening which extends through the wall is sized and operable to support the filter frame. The support frame may be mounted to a wall.

Abstract: A device for the removal of microscopic particles from air includes a tube which in a certain cross-section has a replaceable, suitably ionizing particle separation unit (4) with a multitude of threads or strips (10) which are held together in a common frame structure (11) extending across the tube. The strips (10) are arranged to be set in motion in relation to each other by the passing air, thereby generating static electricity for attracting micro particles from the air to the strips. The frame structure (11) is made of a flexible band formed into loops, the strips being affixed on the band, the frame structure also including a plurality of pipe- or tubeforming members located amongst the band loops, in order to distribute the air flow through the frame structure.

Abstract: A filter apparatus for a reusable one piece filter frame housing and a filter media for use in a forced air ventilating system. The one piece filter frame housing having integrally formed fasteners to releasably secure a replaceable filter media. The filter frame housing further having an "I" beam structure to enhance filter frame strength. The filter frame housing also having an electrostatic charge.

Abstract: A process for after-purifying a kieserite mixture pre-concentrated electrostatically across a number of stages is characterized in that the outside air used in the after purification stage is adjusted by dehumidification in a conventional dehumidification plant to an absolute moisture of 4.5 g/m.sup.3, and the kieserite mixture to be separated by triboelectrically charging with said air at a temperature of below 40.degree. C.

Abstract: A filter apparatus has a rigid housing surrounding a piece of preferably self charging electrostatic filter material and having a preferably magnetic attachment device for mounting the filter apparatus directly in front of a grill at an end of a cold air return or supply of a forced air system, for a heating and/or air conditioning system. The filter and housing are generally sized so that the frame does not cover any of the openings on the grill over which it is designed to be placed. Decorative openwork is positioned in the front of the filter material to provide an aesthetically pleasing covering of what is considered less than attractive filter material.

Abstract: A contaminated air purifying apparatus capable of decreasing particles such as dust floating in air, soot produced by a combustion engine and the like and air pollutants such as nitrogen oxides (NOx) contained in exhaust gas. Particulates such as dust, soot and the like are electrostatically negatively charged and collected in a purifying filter section by coulombic force. NOx is converted into N.sub.2 and CO.sub.2 by an action of carbon fiber or carbon particles, resulting in decreased in concentration. The carbon fiber and carbon particles are preferably modified into an increased surface area of 200 to 2000 m.sup.2 /g.

Abstract: Disclosed is a filter for a reduced threat chemical/biological protective spiratory device which includes a housing having an air intake orifice and an air exit orifice and which encloses a filtering element which includes a plurality of bonded spherical carbon beads arranged in a open cell type matrix. The filtering element also includes an aerosol and particulate filtering element which is a plurality of electrostatically charged polypropylene fibers.

Abstract: A composite filter media is formed of a plurality of layers. A central layer of electrostatically charged material formed of a carded mixture of polyolefin fibers such as polypropylene and electro-negative substituted organic resin fibers such as modacrylic acrylonitrile-vinyl, chloridevinylidene chloride copolymer efficiently filter more than 99% of 0.1 to 0.5 micron particles. A flame retardant prefilter layer of polyester removes large particles and a backing of flame retardant linear polyester provides tear resistance. An optional layer of electrostatically charged, melt blown, polyolefin such as polypropylene prevents the central layer from loading up by effectively filtering intermediate sized particles.

Abstract: A non-ionizing, clog-resistant filter for extracting fine particulate contaminants such as smoke from a gaseous fluid stream such as air uses interaction between Van der Waals forces and a non-ionizing electrostatic field to efficiently capture the contaminant particles in a filter material whose pores are many times larger than the diameter of the particles to be captured. The filter material is physically so configured to further enhance that interaction, and is disposed between at least a pair of electrodes of opposite polarity. The material may be spaced from the electrodes, but preferably touches one of them. The particles are trapped deeply into the thickness of the filter material and leave ample room for continued air flow. The electrostatic voltage is preferably between 3 and 9 kV and is largely independent or electrode spacing. The configuration of the filter material is such that the flow velocity through the material is less than 0.1 m/sec, preferably on the order of 0.03 m/sec.

Abstract: A method and apparatus for separating chaff from coffee and cocoa beans is designed for use in combination with the hot air blowing base of the common household consumer appliance, the electrical popcorn popper. The method comprises a hopper having an open top, an open bottom mountable over the hot air blowing base of the popper for roasting beans and an exhaust gas outlet, a lid for covering the top and a screen mounted over the exhaust gas outlet. The screen is coated with a material that causes its surface to become electrostatically charged during the bean roasting process. The chaff from the beans becomes separated during the roasting process and then is entrained in the exhaust gases which pass upward from the hot air blowing base for roasting the beans and through the open bottom. The chaff is collected on the electrostatically charged screen and is easily removed after the roasting process.

Abstract: A multi-layered electrostatic filter and method of filtration incorporating an insulated poly glass charging element which is a grid of sufficient width to allow the air flow through the charging element to supply a static charge to the charging element and to allow trapped particles to gather and combine or coagulate along the charged element prior to reaching a dust trap which is a second layer of polypropylene filters. The initial charge is generated by friction from the dust and the air passing through a first polypropylene layer. Polypropylene is used in order to provide an insulating frame and insulating dust filters on either side of the poly glass charging element. Progressively fine layers provide for multiloading of particulate material.

Abstract: In order to enhance the efficiency of charging in a friction charger, it is proposed to precharge the particles before the first collision with the walls by making use of the photoeffect. This is performed, preferably, through irradiating the particles using UV radiation from a UV excimer radiator.

Abstract: A method of spectrally sensitizing a photographic light-sensitive emulsion where a water-soluble solution, prepared by dissolving a methine dye having at least one water-soluble group in water in the presence of a "Red Shift Compound", as hereinafter defined, is added to a photographic light-sensitive emulsion to provide a photographic light-sensitive emulsion spectrally sensitized with increased sensitizing efficiency and with reduced fog. The disadvantages caused by the use of high organic solvent contents are avoided and photographic light-sensitive emulsions suitable for high-speed coating are obtained.

Abstract: Electrofax copy paper particularly for dry toner copiers comprises a substantially nonconductive substrate in combination with a photoconductive zinc oxide coating having greater light sensitivity, lower charge characteristicts and greater conductivity than conventional zinc oxide coatings. The substrate does not include any additives specifically for increasing its conductivity but relies on a balanced conductivity from front-to-back as a result of an even distribution of moisture throughout the substrate.

Abstract: A process for preparing a photosensitive material for electrostatic photography having an improved memory resistance, which comprises a photoconductive layer on an electrically conductive substrate, the photoconductive layer comprising (1) a finely divided inorganic photoconductor, (2) 5 to 50 parts by weight, per 100 parts by weight of the photoconductor of an electrically insulating organic synthetic resin binder having a specific resistance of at least 10.sup.14 ohm-cm, and (3) 0.001 to 1 % by weight, based on the photoconductor, of at least one photo-memory erasing compound selected from alkali metal dichromates, which process comprises forming the photoconductive layer by applying a coating composition to the electrically conductive substrate at a coating weight of 5 to 50 g/m.sup.

Abstract: Photographic panchromatic black-and-white silver halide recording material having two silver halide emulsion layers wherein a layer, called hereinafter first layer, has a panchromatic sensitivity and another layer, called hereinafter second layer, has a blue sensitivity, which is, when determined on comparable wedge images, at density 0.3 at least 0.6 log I.t units higher than its separately considered green and red sensitivity, wherein for the determination of the sensitivities a blue filter, a green filter, and a red filter as characterized in FIG. 1 are used, both said layers having a substantially identical threshold sensitivity to blue light and the spectral sensitivity of this material at 650 nm being at least 0.8 powers of ten lower than at 620 nm, the sensitivity beyond 650 nm diminishing even further.

Abstract: A photograph of an object is made on color film in a conventional manner. Then the object is back-lighted only to silhouette it and a second photograph is made using the same film. The two films are developed simultaneously so as to subject them to identical processing conditions. Using the photograph taken while the object was back-lighted, a contact exposure is made on a high contrast film to produce a negative. After development of this negative, it and the initial, front-lighted, photograph of the object are employed on a scanner to produce the color separations for printing purposes.

Abstract: An electrophotographic recording material formed by extrusion, which comprises (A) 100 parts by weight of a blended composition of olefins having high and low melt indices in a specified weight ratio, (B) 0.025 to 40 parts by weight of a specified light-sensitizing organic compound, (C) 200 to 600 parts by weight of particulate photoconductive zinc oxide, (D) 0.06 to 0.4 part by weight, per 100 parts by weight of the total of components (A), (B) and (C), of a specified metal (e.g., Mg, Ca, Zn, Sn) salt of a C.sub.12-20 saturated or unsaturated fatty acid, and (E) 1 to 20 parts by weight of a silicone polymer; the components (B), (C), (D) and (E) being uniformly dispersed in component (A), and the light-sensitizing organic compound (B) being adsorbed to the surface of the zinc oxide (C).

Abstract: A photoconductive member for xerographic applications comprising a mixture of particles of at least two photoconductive pigments capable of generating and injecting holes and electrons dispersed in an insulating binder, capable of transporting holes and electrons in response to imagewise radiation. The photoconductors which are preferred also have a coefficient of absorption between 1/L and 8/L wherein L is the thickness of the photoconductive member in microns. The photoconductive member thus formed is capable of continuous tone reproduction and has improved xerographic characteristics. In a particularly preferred embodiment, one of the photoconductive materials is cadmium sulfoselenide.

Abstract: The present invention provides 1,3,7-trinitrophenazine-5-oxide which has an excellent sensitization effect on organic photoconductors, as well as a photoconductive sensitive material comprising said compound and an organic photoconductor.

Abstract: Coloration resistant photoconductive insulating compositions useful in making elements, such as photoconductive electrophotographic papers, are provided. Such compositions comprise (1) an electrically insulating organic binder, (2) a nitrogen-free polyaryl hydrocarbon photoconductor such as those having the formula ##STR1## wherein: N REPRESENTS AN INTEGER HAVING A VALUE OF 0, 1 OR 2,Ar represents an aryl group including substituted aryl such as phenyl, alkylphenyl having 1 to about 10 carbon atoms in the alkyl moiety, alkoxyphenyl having 1 to about 10 carbon atoms in the alkoxy moiety, and the like,Each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 represents a hydrogen atom, an aryl group, an alkyl group or an alkoxy group and, when n is O, R.sup.1 and R.sup.4 are both aryl and when R.sup.1 and R.sup.4 are both hydrogen, each of R.sup.2 and R.sup.3 represents an aryl group; and (3) a sensitizer that is substantially non-color forming in the composition.

Abstract: The present invention relates to light-sensitive photographic material with a light-sensitive heavy metal compound, e.g. a silver halide, and a spectral sensitizer. The spectral sensitizer is a compound in which the radicals of a sensitizing dyestuff are covalently bonded to amino, imino, hydroxyl, mercapto, carboxylic acid or carboxylic acid amide groups of a natural hydrophilic colloid, preferably gelatin.The invention also relates to new sensitizing dyes which are dinuclear cyanine dyes or merocyanine dyes which have attached either to a heterocyclic nucleus of the dye or to its methine chain a group which is reactive with a hydrophilic colloid.

Abstract: Disclosed is electroconductive paper adapted particularly for use in the manufacture of paper used in the electrophotographic reproduction of images.

Abstract: Toning an electrophotographic layer by adding materials which bleach at different rates, and thereafter selectively bleaching the materials after development.

Abstract: A class of organic pigments having the formula ##STR1## wherein X consists of the atoms necessary to complete a naphthalene, anthracene, or ##STR2## ring; R.sup.1, R.sup.2, and R.sup.3 are hydrogen, halogen, alkoxy, NO.sub.2, alkyl, SO.sub.3 H or alkali metal salts thereof, ##STR3## and COOH or alkali metal salts thereof, and R.sup.2 and R.sup.3 can comprise the atoms necessary to complete a phenyl, naphthyl or anthryl ring; and R is selected from the group consisting of ##STR4## where M is alkyl, alkali or alkaline earth metal are useful as sensitizers for photoconductive compositions in electrophotographic processes.

Abstract: A specific class of crystalline organic pigments having the formula ##STR1## WHEREIN N IS 1 OR 2; X consists of the atoms necessary to complete a naphthalene, anthracene, or ##STR2## R.sup.1, R.sup.2, and R.sup.3 are independently selected from the group consisting of hydrogen, halogen, alkoxy, NO.sub.2, alkyl, SO.sub.3 H or alkali metal salts thereof, and COOH or alkali metal salts thereof; and wherein R.sup.2 and R.sup.3 can comprise the atoms necessary to complete a phenyl, naphthyl or anthryl ring; and R is selected from the group consisting of ##STR3## or COOM wherein M is alkyl or an alkali or alkaline earth metal is useful as sensitizers for photoconductive compositions in electrophotographic processes.

Abstract: A photosensitive element comprising a support having thereon at least one photosensitive silver halide emulsion layer and one of said layers having associated therewith a yellow image dye-releasing compound having a formula as follows ##STR1## wherein Car represents a sulfonamidophenol or sulfonamidonaphthol carrier moiety which, as a function of oxidation under alkaline conditions, releases a diffusible dye from said compound.X represents a bivalent linking group of the formula --R.sup.1 --L.sub.n --R.sup.1.sub.p -- where each R.sup.

Abstract: A photosensitive layer comprises (a) at least one heterocyclic photochromic spiropyrane which can exist in a closed or open structure, the closed structure being converted to the open structure on irradiation with ultra-violet light, and the open structure being reconverted to the closed structure on irradiation with visible light, (b) at least one ortho-substituted nitrogen-containing thioether, and (c) at least one reagent capable of developing a latent image produced in the layer. In use of the layer, it is exposed to ultra-violet or visible light, and after exposure the layer is heated to cause conversion of the thioether to a thione at those areas of the layer in which spiropyrane in the open form is present: the spiropyrane in the open form catalyzing the conversion of thioether to thione and thereby amplifying the latent image produced on irradiation of the layer. The thione produced then reacts with the developing reagent to form a visible image.

Abstract: A process is described for performing color separations from a light-image of a colored original and for separately printing corresponding color separation images in registry onto a print sheet to provide a full color reproduction. The printing step is accomplished by thermographic dry image forming techniques.

Abstract: Films in which the various color gradients are particularly balanced in relationship to each other are prepared from sensitized emulsions prepared separately and then either coated as separate layers or mixed just prior to coating. These films are particularly useful as color separation negatives where machine processing is used and where identical processing conditions for each color record are desirable.

Abstract: A method for modifying vesicular images into non-scattering images is provided, which comprises opening the closed bubbles of the vesicular image to form an open-bore image by allowing at least one organic solvent which attacks the thermoplastic bubble walls of the vesicular image to act on the latter, optionally making the image wettable with a surfactant introducing the image substance into the open pores by treatment with a solution or dispersion of the image substance and, optionally removing any remaining gas bubbles or pores by heat or solvent treatment.

Abstract: Negative continuous-tone images or continuous-tone separation records having standardized contrast are produced from originals which are differing in contrast by means of a photograhic material the silver halide emulsion of which has a characteristic curve with a sagging course defined below, whereby the part of characteristic curve which is utilized for the production of the continuous-tone negative depends on the contrast of the original.

Abstract: An aggregate or heterogeneous multiphase photoconductive composition containing a continuous polymer phase and at least one discontinuous phase dispersed in said continuous phase, said discontinuous phase comprising a co-crystalline complex of (i) at least one polymer having an alkylidene diarylene group in a recurring unit (ii) at least one pyrylium type dye salt having a non-light absorbing anion, and (iii) at least one pyrylium type dye salt having a colored organic or organo-metallic anion of a strong acid.

Abstract: A method of making a photographic print having improved sharpness, clarity, texture and highlight definition, suitable for use in dye-transfer printing, engraving, lithography, offset, and the like, involves the production of a primary color separated negative of the image to be printed on a panchromatic film, producing a separated color positive from the separated color negative, producing a reversal positive from the separated color positive on direct reversal film so as to produce a panchromatic primary color separated reversal positive, producing a composite separation negative from the separated color positive and the reversal positive, and producing the desired photographic positive from the composite negative.