# US 10,870,130 B2 · Method for preparing fine powders for use in selective laser sintering processes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,870,130 B2 - Document ID: US10870130B2 - Status: Granted - Kind: B2 - Application number: 14/740,602 - Filed: 2015-06-16 - Published: 2015-11-19 - Granted: 2020-12-22 - Earliest claimed: 2012-12-19 - Assignees: Hexcel Corporation - Applicants: Hexcel Corporation - Inventors: Scott DeFelice; Anthony DeCarmine - Web page: https://patentgrep.com/patent/US10870130B2 ## CPC - B07B 13/04: according to size - B02C 23/08: Separating or sorting of material, associated with crushing or disintegrating (B02C23/18 takes precedence {; beater mills combined with sifting devices B02C13/13, B02C13/14; for tumbling mills B02C17/1835}) - B07B 15/00: Combinations of apparatus for separating solids from solids by dry methods applicable to bulk material, e.g. loose articles fit to be handled like bulk material (using wet methods B03B7/00; using gas currents B07B9/00) - B33Y 40/10: Pre-treatment - C08J 3/12: Powdering or granulating - B29C 64/153: using layers of powder being selectively joined, e.g. by selective laser sintering or melting - B29K 2071/00: Use of polyethers {, e.g. PEEK, i.e. polyether-etherketone or PEK, i.e. polyetherketone or derivatives thereof}, as moulding material - C08J 2371/00: Characterised by the use of polyethers obtained by reactions forming an ether link in the main chain; Derivatives of such polymers - B07B: SEPARATING SOLIDS FROM SOLIDS BY SIEVING, SCREENING, SIFTING OR BY USING GAS CURRENTS; SEPARATING BY OTHER DRY METHODS APPLICABLE TO BULK MATERIAL, e.g. LOOSE ARTICLES FIT TO BE HANDLED LIKE BULK MATERIAL (wet separating processes, sorting by processes using fluent material in the same way as liquid B03; combinations of dry separating apparatus with wet separating apparatus B03B; using liquids B03B, B03D; sorting by magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high voltage electric fields B03C; centrifuges or vortex apparatus for carrying out physical processes B04; hand sorting, postal sorting, sorting by switching or other devices actuated in response to detection or measurement of some feature of articles or samples of material B07C) - B02C: CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN ({household tools and machines for pulverising foodstuffs, e.g. coffee and spice mills A47J42/00; pharmaceutical mortars A61J3/02; mechanical processing of refuse and garbage B03B9/06; dressing mould materials by grinding B22C5/04}; obtaining metallic powder by crushing, grinding or milling B22F9/04; {recovery of plastics by disintegrating B29B17/00; crushing raw materials in starch making C08B30/02; beaters for papermaking D21D1/02; crushing devices specially for transport in mines E21F13/002; slag crushing devices F23J1/00; fuel milling devices in combustion apparatus F23K1/00; household devices for crushing coal F24B15/02; ice disintegrating devices F25C5/02}) - B33Y: ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B29K: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR {MOULDS, } REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS ## Abstract A process for preparing a feedstock having polyaryletherketone particles for using in selective laser sintering. The process includes the steps of determining a particle size distribution of the polyaryletherketone particles in the feedstock based on a number of particles corresponding to each of a plurality of particle size ranges to obtain a particle size distribution determination. The process further includes the step of reducing the number of particles in the feedstock corresponding to one or more size ranges having a depressed melting temperature relative to the average melting temperature of the polyaryletherketone particles in the feedstock based on the particle size distribution determination. ## Claims ### Claim 1 A process for preparing a feedstock with a plurality of polyaryletherketone (PAEK) particles for selective laser sintering, each of the plurality of PAEK particles within one of a plurality of particle size ranges, the process comprising the steps of: determining a particle size distribution of the plurality of PAEK particles in the feedstock based on respective numbers of the plurality of PAEK particles within each of the plurality of particle size ranges, the plurality of particle size ranges having at least three size ranges; identifying at least two of the plurality of particle size ranges having a depressed melting temperature relative to the average melting temperature of the plurality of PAEK particles in the feedstock based on the particle size distribution determination by number, and reducing the respective numbers of the plurality of PAEK particles in the feedstock within the at least two of the plurality of particle size ranges having a depressed melting temperature relative to the average melting temperature of the plurality of PAEK particles in the feedstock based on the particle size distribution determination to form a prepared feedstock, the at least two of the plurality of particle size ranges have a particle diameter of 20 microns or less; using the prepared feedstock in a selective laser sintering process comprising the step of applying a layer of the prepared feedstock on a bed of a laser sintering machine, solidifying selected points of the applied layer of the prepared feedstock by irradiation, successively repeating the step of applying the prepared feedstock and the step of solidifying the applied layer of the prepared feedstock until all cross sections of a three-dimensional object are solidified. ### Claim 2 (depends on 1) The process of claim 1 further comprising the step of: determining a particle size distribution of the plurality of PAEK particles in the prepared feedstock based on respective numbers of the plurality of PAEK particles within each of the plurality of particle size ranges to confirm a sufficient number of particles having a depressed melting temperature have been removed from the feedstock. ### Claim 3 (depends on 1) The process of claim 1 wherein the depressed melting temperature is between 5 and 50 degrees Celsius below the average melting temperature of the plurality of PAEK particles in the feedstock. ### Claim 4 (depends on 1) The process of claim 1 further comprising the step of reducing the respective numbers of the plurality of PAEK particles in the feedstock within any of the plurality of particle size ranges comprising particle diameters of 10 microns or less. ### Claim 5 (depends on 1) The process of claim 1 further comprising the step of reducing the respective numbers of the plurality of PAEK particles in the feedstock within any of the plurality of particle size ranges comprising particle diameters of 15 microns or less. ### Claim 6 (depends on 1) The process of claim 1 further comprising the step of reducing the respective numbers of the plurality of PAEK particles in the feedstock within any of the plurality of particle size ranges comprising particle diameters of 25 microns to 20 microns. ### Claim 7 (depends on 1) The process of claim 1 further comprising the step of reducing the respective numbers of the plurality of PAEK particles in the feedstock within any of the plurality of particle size ranges comprising particles diameter of 30 microns to 20 microns. ### Claim 8 (depends on 1) The process of claim 1 wherein the feedstock comprises polyetherketoneketone (PEKK) particles. ### Claim 9 (depends on 8) The process of claim 8 wherein the depressed melting temperature is 5 or more degrees Celsius below the average melting temperature of the PEKK particles in the feedstock. ### Claim 10 A process for preparing one or more polyaryletherketones for selective laser sintering, the process comprising the steps of: pulverizing the one or more polyaryletherketones to form a powder comprising polyaryletherketone (PAEK) particles, determining a particle size distribution of the PAEK particles based on respective numbers of the PAEK particles within each of a plurality of particle size ranges, the plurality of particle size ranges having at least three size ranges; creating a feedstock from the PAEK particle, limiting the respective numbers of the PAEK particles in the feedstock corresponding to at least two of the plurality of particle size ranges based on the particle size distribution determination by number, at least two of the plurality of particle size ranges having particle diameters of 20 microns or less using the prepared feedstock in a selective laser sintering process comprising the step of applying a layer of the prepared feedstock on a bed of a laser sintering machine, solidifying selected points of the applied layer of the prepared feedstock by irradiation, successively repeating the step of applying the prepared feedstock and the step of solidifying the applied layer of the prepared feedstock until all cross sections of a three-dimensional object are solidified. ### Claim 11 (depends on 10) The process of claim 10 further comprising the step of determining a particle size distribution of the PAEK particles in the feedstock after the limiting step based on respective numbers of the PAEK particles within each of a plurality of particle size ranges to confirm a sufficient number of particles in the at least two of the plurality of particle size ranges having particle diameters of 20 microns or less are removed from the feedstock. ### Claim 12 (depends on 10) The process of claim 10 further comprising the step of limiting the respective numbers of PAEK particles in the feedstock within one or more of the plurality of particle size ranges having particle diameters of 10 microns or less. ### Claim 13 (depends on 10) The process of claim 10 further comprising the step of limiting the respective numbers of PAEK particles in the feedstock within one or more of the plurality of particle size ranges having particle diameters of 15 microns or less. ### Claim 14 (depends on 10) The process of claim 10 further comprising the step of limiting the respective numbers of PAEK particles in the feedstock within one or more of the plurality of particle size ranges having particle diameters of 25 microns to 20 microns. ### Claim 15 (depends on 10) The process of claim 10 further comprising the step of limiting the respective numbers of particles in the PAEK feedstock within one or more of the plurality of particle size ranges having particle diameters of 30 microns to 20 microns. ### Claim 16 (depends on 15) The process of claim 15 wherein the feedstock comprises polyetherketoneketone (PEKK) particles. ### Claim 17 (depends on 16) The process of claim 16 wherein the depressed melting temperature is 5 or more degrees Celsius below the average melting temperature of the PEKK particles.