Abstract: Disclosed herein are roll fed air heated flotation ovens and related thermoforming systems, assemblies, and machines that enable the corrugation-free expansion of a gas impregnated thermoplastic web passing through an oven chamber (without use of a pin-chain assembly), as well as to related methods. In an embodiment, a gas impregnated thermoplastic web is conveyed and expanded through an elongated air heated oven chamber, wherein the elongated oven chamber includes a plurality of downwardly directed heated air nozzles positioned at regular intervals along and within the upper portion of the oven chamber, and a plurality of upwardly directed heated air nozzles positioned at regular intervals along and within the lower portion of the oven chamber, but staggered apart from the downwardly directed heated air nozzles such that the gas impregnated thermoplastic material web undulates in an up and down wavelike fashion, thereby minimizing sagging, bagging, puckering, and/or buckling of the web.

Abstract: Provided are methods for making textured implantable materials made from two part RTV silicone foams and having a desired color or tone without the need for dyes or colorants.

Abstract: A method of making a vehicle interior panel substrate with a reduced thickness portion along a boundary of an airbag door includes molding the substrate using a substrate mold that includes a movable mold member. The movable mold member is part of a mold section and moves with respect to other portions of the mold section during the molding process to form the reduced thickness portion, which may include a hinge or a tear seam. The mold member moves after plastic material is introduced into the mold cavity. The plastic material is allowed to expand when substrate mold sections are moved away from each other. Plastic material expansion may be part of a structural gas injection (SGI) process. A scrim material or other hinge reinforcement may be molded into the substrate.

Abstract: An automotive interior material with high appearance quality and a method of manufacturing the same includes a door trim (automotive interior material) having a flat portion (main-body portion) covering a door panel and an armrest protruding into the vehicle compartment. Molten resin material added with a foaming agent is supplied into a cavity formed between a pair of molds. Then, opening of the pair of molds by a predetermined amount causes the molten resin material in the cavity to foam. An upper surface (vertical wall portion) of the armrest is connected to the flat portion and extends in a thickness direction of the flat portion. A surface of the upper surface facing outward from the vehicle compartment is formed with a recessed portion. During a vehicle collision, an object in the vehicle presses the arm rest formed on the door trim. Then the door trim is broken and deformed in the recessed portion, so that the armrest is crushed, thus absorbing an impact by a collision.

Abstract: This disclosure provides (meth)acryloyl pressure-sensitive adhesive foams and foam articles having one or more of the following properties: small cells, uniform cell sizes, pressure sensitive adhesive compositions, compliance to irregular substrates and vibration damping, and shock absorbing properties.

Abstract: A method for producing a hollow foam molding having a thin and uniform wall thickness, including extruding a foamable melt containing a polypropylene resin having an equilibrium compliance Jeo of 0.5×10?3 to 1.8×10?3 Pa?1 and a swell ratio Sw of 2.5 or less and a physical blowing agent through a die to obtain a parison having a softened polypropylene resin foam layer, placing the parison in a mold, and blowing a gas into the parison to obtain a hollow foam molding having a hardened polypropylene resin foam layer with an apparent density of 0.35 to 0.65 g/cm3.

Abstract: Process for the production of nanoporous polymer foams, comprising the stages a) loading of a single-phase, thermoplastic polymer melt with a gas under a pressure and at a temperature at which the gas is in the supercritical state, b) heating of the laden polymer melt to a temperature which lies in the range from 40° C. under to 40° C. over the glass transition temperature of the unladen polymer melt determinable by means of DSC according to DIN-ISO 11357-2 at a heating rate of 20 K/min, c) depressurization of the polymer melt loaded in stage a) and heated in stage b) with a depressurization rate in the range from 15,000 to 200,000 MPa/sec, and the nanoporous polymer foams with a cell count in the range from 1,000 to 100,000 cells/mm and a density in the range from 10 to 500 kg/m3 obtainable according to the process.

Abstract: Pearls based on expanded polymers are produced by extruding an expandable composition containing a thermoplastic polymer and an expanding agent, and thereafter cooling and chopping the expanded material thus obtained.

Abstract: The present invention provides a stretched thermoplastic resin foam sheet that has excellent flexibility even compressed to a thickness as thin as about 0.05 mm, and a method for producing the same. The stretched thermoplastic resin foam sheet of the present invention is producible by stretching a thermoplastic resin foam sheet and has a compressive strength of 1 to 500 kPa as measured in accordance with JIS K6767 when compressed in a thickness direction thereof to a thickness of 0.05 mm. Accordingly, the stretched thermoplastic resin foam sheet has excellent flexibility even compressed to a thickness as thin as about 0.05 mm and is suitably used as a sealing material for a small electronic device such as mobile phones.

Abstract: Provided are methods for producing a high strength, but easily deformed, polystyrene foam board that can endure repeated deformations from its original configuration into more complex curved shapes without damaging the board integrity or substantially reducing its structural strength. Also provided are rigid polystyrene foam boards produced by this method that exhibit improved bending and impact resistance while substantially retaining or improving other properties, for example, the thermal dimensional stability and fire resistance, exhibited by corresponding conventional XPS foam boards. The foamable compositions may incorporate one or more of a variety of polymer processing aids for the purpose of altering the performance of the final foam products, thereby allowing the properties of the final foam product to be customized to some degree.

Abstract: A molding apparatus for making a continuous molded article generally includes a pair of spaced-apart molding assemblies, which cooperatively generate a movable mold having a dynamic mold-cavity therein, each of the molding assemblies including a series of movable mold segments, which are adapted to fit together to form a portion of the dynamic mold-cavity, a drive mechanism for conveying the mold segments along a path, and a dispenser for dispensing a moldable, expandable material into the dynamic mold-cavity.

Abstract: The object is to propose an improved process for the production of a polyimide foam by which a large-sized polyimide foam in a state of fine and homogeneous cells can be readily obtained by easy operations and convenient steps. A melt-shaped body of a polyimide precursor obtainable by melt-treating in a closed state a powder of a polyimide precursor including at least an aromatic tetracarboxylic acid ester component and an aromatic amine component. A process for the production of a polyimide foam including the steps of melt-shaping in a closed state a powder of a polyimide precursor including at least aromatic tetracarboxylic acid ester component and an aromatic amine component to give a melt-shaped body of the polyimide precursor, and foaming the melt-shaped body of the polyimide precursor by a heat treatment.

Abstract: A process for the production of expanded PVC of the type includes heating a mass of polymeric mixture inside a closed mold; controlling the expansion of the mass in an environment having a constant volume defined by the closed mold, control being performed by the presence, in the mass of polymeric mixture, of microparticles of a compressible material, suitable for being contracted, under the action of the pressure generated by the formation and expansion of microcells of expanding gas in the same mass, from an initial form having a larger volume, to a form having a smaller volume; and expanding the microparticles, from their configuration to the initial configuration, the density of the expanded material thus obtained being determined by the contemporary presence of both microcells of expanding gas and the microparticles in their configuration having a larger volume.

Abstract: Described herein are open celled foams including a matrix of interconnected spheres. Also described herein are methods of making open celled foams as well as making composite members with open celled foam coatings covering at least a portion of the composite member. The open celled foams described herein are silicone based materials and can be used to coat implants such as breast implants and function to encourage tissue ingrowth and reduce capsular formation.

Abstract: A double-sided, slip resistant material is produced using a blown film process which produces a film having an interior heat sealable layer, a core layer of flexible polyolefin and an exterior polyolefin elastomer layer in combination with a blowing agent and optionally grit to produce a double-sided slip resistant material. A number of rollers are provided after nip rollers have fused the film together, and which form part of a machine direction orienter (MDO) that is used in line in the manufacturing process to heat, and then cool and condition (anneal and relieve any stresses and/or thickness inconsistencies in the film) prior to the film being wound onto a roll for storage.

Abstract: This invention provides composite semiconductor substrates and methods for fabricating such substrates. The composite structures include a semiconductor substrate, a semiconductor superstrate and an intermediate layer interposed between the substrate and the superstrate that comprises a material that undergoes a structural transformation when subject to a suitable heat treatment. The methods provide such a heat treatment so that the intermediate layer becomes spongy or porous, being filled with numerous micro-bubbles or micro-cavities containing a gaseous phase. The composite semiconductor substrates with structurally-transformed intermediate layers have numerous applications.

Abstract: Prepare an extruded polymeric foam by extruding a foamable polymer composition through a foaming die and allowing the foamable polymer composition to expand into a polymer foam as it travels through and is constrained in its thickness dimension by at least two constraining sections, the first having opposing essentially parallel forming plates and the second constraining section having forming plates spaced further apart than the first constraining section.

Abstract: The present disclosure relates to a method for producing composite materials containing as a first layer a foamed thermoplastic support and as a second layer polyurethane (PU), the resulting composite materials being characterized by improved foam adhesion, wherein (i) a foamed polycarbonate molding composition is produced by injection molding using chemical or physical foaming techniques, and (ii) the polyurethane reaction system is applied on top and allowed to cure. The disclosure also provides the composite systems produced by this method and their use as a component, in particular in the automotive sector.

Abstract: Molded flexible polyurethane foam is made from a polyol mixture that contains a dispersion of polymer particles in one or more polyether polyols of a particular type and one or more high functionality, high-ethylene oxide polyols which have an average oxyethylene content of from 26 to 100% by weight, an average hydroxyl equivalent weight of from 1400 to 2200 and an average nominal hydroxyl functionality of from 6 to 10. The polyol mixture produces a foam that has excellent resiliency and low compression sets.

Abstract: A process for the production of expanded PVC of the type includes heating a mass of polymeric mixture inside a closed mold; controlling the expansion of the mass in an environment having a constant volume defined by the closed mold, control being performed by the presence, in the mass of polymeric mixture, of microparticles of a compressible material, suitable for being contracted, under the action of the pressure generated by the formation and expansion of microcells of expanding gas in the same mass, from an initial form having a larger volume, to a form having a smaller volume; and expanding the microparticles, from their configuration to the initial configuration, the density of the expanded material thus obtained being determined by the contemporary presence of both microcells of expanding gas and the microparticles in their configuration having a larger volume.

Abstract: The invention relates to a process for producing expandable pelletized material which comprises polylactic acid which comprises the following steps: a) melting and incorporation by mixing of the following components: i) from 50 to 99.9% by weight, based on the total weight of components i to iii), of polylactic acid, ii) from 0 to 49.9% by weight, based on the total weight of components i to iii), of one or more further polymers, iii) from 0.1 to 2% by weight, based on the total weight of components i to iii), of a diepoxide or polyepoxide, and iv) from 0 to 10% by weight of one or more additives, b) incorporation by mixing of v) from 3 to 7% by weight, based on the total weight of components i to iv), of an organic blowing agent into the polymer melt by means of a static or dynamic mixer at a temperature of at least 140° C., c) discharging through a die plate with holes, the diameter of which at the exit from the die is at most 1.

Abstract: An abradable panel for a fan track liner assembly comprises an abradable layer comprising a syntactic material. The abradable panel is arranged to be attached to a fan track liner so as to provide an abradable gas-washed surface. The abradable panel may further comprise a carrier tray to which the abradable layer is attached. There is also disclosed a method of manufacturing an abradable panel.

Abstract: The present invention relates to a microcellular foam of a thermoplastic resin and a method for preparing the same, and more particularly to a microcellular foam comprising a skin layer having a porosity of below 5% and a core layer having a porosity of at least 5%, wherein the thickness of the skin layer accounts for 5 to 50% of the entire foam, and a method for preparing the same. The microcellular foam of the present invention is advantageous in that it has a thicker skin layer and smaller and uniform micropores in the core layer, compared with conventional microcellular foams, while having mechanical properties comparable to those of conventional non-foamed sheets.

Abstract: A chemical-mechanical planarization polishing pad is provided comprising a network of elements dispersed within a polymer, a plurality of voids formed in the pad and at least a portion of said network of elements is connected to at least a portion of the voids. A method of forming the pad is also disclosed, which comprises providing a composition, the composition comprising a network of elements and at least one of a polymer or a reactive prepolymer, introducing a gas to the composition and using the gas to produce a plurality of voids in the composition. A method of forming voids is also disclosed, which relies upon the application of a force to the network of elements within the polymer or reactive polymer, followed by removal of the force and void formation.

Abstract: Provided is a method that can improve formability and blow moldability of a foamed parison as compared with conventional production method and can produce a polypropylene-based resin foamed blow-molded article having excellent uniformity of wall thickness over a wide range of its density. The method comprises kneading a polypropylene-based resin with a physical foaming agent, extruding the thus obtained foamable molten resin through a die to obtain a foamed parison in a softened state, placing the foamed parison between molds and then blow-molding the foamed parison and is characterized in that the polypropylene-based resin comprises a polypropylene-based resin (A) satisfying specific requirements (1) to (3) and a polypropylene-based resin (B) satisfying a specific requirement (4), when the polypropylene-based resins (A) and (B) are each subjected to dynamic viscoelasticity measurement in which an oscillation strain is applied thereto at a temperature of 190° C.

Abstract: To provide a foam board of a polyolefin resin which has an excellent heat insulating property and sound absorption property, of which a product can be material-recycled and which can continuously be produced at a low cost; a method for producing a foam board, which comprises extrusion-foaming by ejecting a mixture of a polyolefin resin composition containing a linear polypropylene resin having a melt tension of from 5 to 30 g at 230° C. and a foaming agent containing at least carbon dioxide in the supercritical state, by means of an extruder which has a multi-hole type die having an opening diameter of from 0.1 to 1.0 mm and the number of openings of from 50 to 5,000 at an ejection amount (V) of from 0.05 to 0.45 kg/hr per one opening in the die at a melt-extrusion temperature of from 160 to 250° C., under atmosphere at a proximal resin pressure of from 7 to 20 MPa at the openings of the die.

Abstract: Methods for reducing the density of thermoplastic materials and the articles made therefrom having similar or improved mechanical properties to the solid or noncellular material. Also disclosed are improvements to foaming methods and the cellular structures of the foams made therefrom, and methods for altering the impact strength of solid or noncellular thermoplastic materials and the shaping of the materials into useful articles.

Abstract: An example molding method includes: feeding a molten foamable resin by injection in a cavity formed in a molding die; allowing the molten foamable resin to flow in the cavity; and foaming and solidifying the molten foamable resin to mold a resin foam product. The example molding method performs flow rate control by controlling a flow rate of the molten foamable resin at a welding portion to be equal to or higher than a flow rate of the molten foamable resin at an upstream portion adjacent to the welding portion.

Abstract: A non-lathering personal care article in the form of a porous dissolvable solid structure, comprising: from about 0% to about 10% ionic surfactant; from about 1% to about 60% of a non-surfactant cosmetic active; from about 15% to about 70% polymeric structurant, wherein the polymeric structurant has a weighted average molecular weight of from about 40,000 to about 500,000; and from about 1% to about 30% plasticizer. The article has a density of from about 0.03 g/cm3 to about 0.15 g/cm3.

Abstract: A styrene-modified polypropylene type resin particle of the present invention includes: a polypropylene type resin and a polystyrene type resin, wherein the polystyrene type resin is included at 30 parts by weight or more but less than 600 parts by weight per 100 parts by weight of the polypropylene type resin, and polystyrene type resin particles having a longitudinal diameter of 5 ?m or less are dispersed in the polypropylene type resin.

Abstract: Provided are methods for producing a high strength, but easily deformed, polystyrene foam board that can endure repeatedly deformations from its original configuration into more complex curved shapes without damaging the board integrity or substantially reducing its structural strength. Also provided are rigid polystyrene foam boards produced by this method that exhibit improved bending and impact resistance while substantially retaining or improving other properties, for example, the thermal dimensional stability and fire resistance, exhibited by corresponding conventional XPS foam boards. The foamable compositions may incorporate one or more of a variety of polymer processing aids for the purpose of altering the performance of the final foam products, thereby allowing the properties of the final foam product to be customized to some degree.

Abstract: A conductive paste, a printed circuit board using the conductive paste, and a method of manufacturing the printed circuit board are disclosed. A conductive paste that includes conductive particles, a polymer, and a polymer foam, can reduce the number of printing repetitions, to simplify the manufacturing process, decrease process times, and improve reliability.

Abstract: An injection molding machine includes a gas feeding mechanism configured to feed gas to a cavity formed between a first mold plate and a second mold plate in a clamped state; an injection apparatus configured to inject a foamable resin into the cavity having an inside pressure thereof increased to be higher than an atmospheric pressure by the gas feeding mechanism; and a gas releasing mechanism configured to release the gas inside the cavity to an atmosphere through a gap formed between an inner wall surface of a through hole formed through one of the first mold plate and the second mold plate and an outer circumferential surface of a mold member inserted into the through hole, during or after the injection of the foamable resin by the injection apparatus.

Abstract: A disclosed method of manufacturing an image display element structure includes a coating step of coating a substrate surface including a plurality of recessed portions arranged at predetermined intervals, with a coating material that is plastic-deformable, in such a manner as to maintain spaces in the recessed portions; and an expanding step of forming gaps in the coating material coating the substrate surface by expanding gas in the spaces, wherein the gaps correspond to the recessed portions; and a peeling step of peeling off the coating material in which the gaps have been formed, from the substrate surface.

Abstract: A laminar structure (1) for providing foam within cavities such as those in automobile pillars and rails is provided comprising a metal foil (4) having a central section (2) and two end sections (3, 4), the central section carrying a foamable material (5) and the end sections being securable to the flanges (8, 9, 15, 16) of the cavity forming members (7, 14). The cavity containing the foam after foaming is also provided.

Abstract: Compression molded polymeric foam articles and methods are described herein. Equipment design and processing techniques may be controlled to form compression molded articles having desired characteristics.

Abstract: It is an object of the present invention to provide: a foaming mold having a high expansion ratio and a light weight and having an excellent appearance with no surface roughness; and a method for producing a foaming mold, whereby even in the case of using thermally expandable microcapsules for injection molding, the thermally expandable microcapsules can expand uniformly to give a foaming mold having a high expansion ratio and an excellent appearance. The invention is a foaming mold having uniform and closed cells, which has a cell diameter of 60 to 120 a specific gravity of 0.6 g/ml or less, and a surface roughness of 4 ?m or less.

Abstract: Making foamed polyolefin tapes can include combining a polyolefin resin and a chemical blowing agent to form a mixture. This mixture can then be heated in an extruder to create a supersaturated solution of gas within the polyolefin resin. A cooling device can be positioned adjacent to a die at a set distance for receiving extruded resin and for allowing exposure of the extruded resin to ambient air between a die outlet and the cooling device. This predetermined distance or space between the cooling device and die outlet allows bubbles to grow in the extruded resin and to be shaped such that voids or empty spaces can be generated within the extruded polyolefin resin. The voids or empty spaces allow the formation of tapes which use less material but have adequate strength for various applications, such as for carpet backings, geotextiles, packaging, housewrap, bags, wire insulation, and reinforcement elements in concrete.

Abstract: A method of making foamed articles that includes providing a copolymer composition, combining the copolymer composition and cellulosic fibers, applying heat, mixing energy and pressure to the copolymer composition and cellulosic fibers mixture to form a foamable mixture, and forming the foamed article by placing the foamable mixture in a molding or extruding operation. The copolymer composition includes a copolymer of 51% to 99.9% of primary monomers, 0.1% to 49% of anhydride containing monomers, and 0% to 25% of other monomers and 0% to 30% of elastomeric polymers. This is combined at 30% to 99.99% copolymer composition with 0.01% to 70% by cellulosic fibers such that the copolymer anhydride groups react with the cellulosic fiber hydroxyl groups to produce a blowing agent byproduct to form a foamable mixture. The foamed article has a density of not more than 1.3 g/cm3.

Abstract: An automobile wallpaper, and an exterior surface finishing agent for the door trim, seats, and so on, of automobiles, as well as its manufacturing method. To manufacture such automobile wallpaper, a printing process is performed on the surface of a surface material which is currently being used, in order to render a three-dimensional effect to the surface, so as to achieve various luxurious appearances. The three-dimensional effect of the printing is maintained even during the molding process, and it also possesses excellent properties relative to sound absorbency, due to the three-dimensional effect of the surface.

Abstract: Process for the production of moldings from nanoporous polymer materials, comprising the stages of a) preparation of a multiphase polymer mixture with domains in the range from 5 to 200 nm, b) impregnation of the polymer mixture with a blowing agent, where the solubility of the blowing agent in the phase forming the domains is at least twice as high as in the adjacent phases, c) expansion of the multiphase polymer mixture comprising blowing agent, by introducing the polymer mixture into a cavity and expanding it therein, thus obtaining the molding.

Abstract: Provided is an injection foaming mold capable of preventing, when formed resin molding is performed by a partial core back, degradation of an outer appearance and component precision, and occurrence of swelling when a portion that is not subjected to the core back is taken out of a die. The injection foaming mold includes at least: a fixed core that avoids moving; and a movable core that performs the core back. The injection foaming mold further includes a capacity change shape portion, which is formed in a region in which a capacity in the die is changed smoothly and continuously from the fixed core side to the movable core side, the capacity change shape portion being formed at a boundary between the fixed core and the movable core.

Abstract: A structure includes a skin and a foam member. The foam member has a molded contour, the mold contour being configured to provide tooled surface for the skin. When the skin is a composite skin, the foam member provides support for the skin so that the skin can be cured under heat and pressure. A method of making the foam member for a foam stiffened structure includes creating a mold having an interior cavity which resembles a desired shape the foam member. A subsequent step involves introducing a foam mixture into the mold. Next, the foam mixture is allowed to polymerize so as to expand and distribute within the cavity of the mold. The method further includes selectively controlling a density of the foam member in the mold. The foam member is at least partially cured. The foam member is assembled with a skin to produce the foam stiffened structure.

Abstract: Closed cell silicone foams are formed by subjecting a silicone base to an inert gas at an elevated pressure, preferably after a pre-curing step, reducing the pressure to allow the base to expand to produce closed cell silicone foam and curing this expanded foam at an elevated temperature.

Abstract: A process for producing polystyrene foam particles having a bulk density in the range from 40 to 400 g/l by extrusion of a polystyrene melt comprising carbon dioxide and/or water as blowing agent through a nozzle and underwater pelletization, wherein the underwater pelletization is carried out at a pressure in the range 1-30 bar.

Abstract: Injection molding systems and methods useful for making microcellular foamed materials are provided as well as microcellular articles. Pressure drop rate and shear rate are important features in some embodiments, and the invention provides systems for controlling these parameters in an injection molding system. Another aspect involves an injection molding system including a nucleator that is upstream of a pressurized mold. Another aspect involves an extrusion system with the reciprocating screw for forming a single phase solution of non-nucleated blowing agent and polymeric material. Another aspect involves very thin walled microcellular material and very thin walled polymeric material. Another aspect provides a method for producing high weight reductions in very thin-walled parts with surfaces that have no noticeable differences from non-foamed parts.

Abstract: Provided is a method for generating structural foam having a density in the range of from 0.4 to 0.75 gr/cm3. A gas is generated in a plastic melt under conditions inhibiting bubble formation in the melt. The melt is injected into a mold and the volume of the mold is varied to produce a structural foam having a density in the specified range. Also provided is a sheet of structural foam having a density in the range of from 0.4 to 0.75 gr/cm3 and a panel including a sheet of structural foam. Also provided is a structure including two or more panels. The structure may be, for example, a cabinet, cupboard, shed or piece of furniture.

Abstract: There are provided a forming device capable of drying at a high speed and of manufacturing a thermosetting resin foam plate more efficiently and stably without multilayering any unnecessary surface material, and a method of efficiently manufacturing a thermosetting resin foam plate therefor. A thermosetting resin foam plate is manufactured by: mixing a resin composition containing at least a thermosetting resin, a foaming agent and a curing agent in a mixer; continuously discharging the resin composition on a traveling air-permeable and flexible surface material, and at the same time covering the upper surface of the resin composition with an air-permeable and flexible surface material; and passing the covered resin composition through a forming device equipped with conveyors having apertures having an aperture area ratio of 15% or more and 80% or less to form and cure the resin composition.

Abstract: A method of producing a multi-microchannel, flow-through element, including the steps of providing a body of material, and producing multiple microchannels within the body, wherein the microchannels extend through the body to produce a multi-microchannel, flow-through element. Such an element can be used as a micromixer, a sensor element, a filter, a fuel element or a chromatographic element.

Abstract: Disclosed is an expanded polypropylene copolymer resin particle whose base resin is a polypropylene random copolymer resin having a melting point of not more than 145° C., the base resin having a H/W ratio of not more than 8 where H (%) is a maximum height of an elution peak and W (° C.) is a peak width at half a height of the peak in an elution curve obtained from a differential value of eluted content measured by cross fractionation chromatography, and a ratio (Mw/Mn) of a weight-average molecular weight (Mw) and a number-average molecular weight (Mn) being not less than 3.5 in a molecular weight distribution measurement of a whole of eluted components. With such an expanded polypropylene copolymer resin particle, it is possible to provide expanded polypropylene copolymer resin particles which are capable of producing an in-mold expansion-molded article with a low molding heating vapor pressure, and which causes few deformation or shrinkage of an obtained in-mold expansion-molded article (i.e.