Abstract: The invention relates to a molding composition containing: (a) a polycarbonate component; (b) a polyester component; (c) a polyamide component; (c) a halogenated flame retarding component; and (d) a carboxy reactive component. The composition exhibits excellent properties that are highly useful in applications such as electronic components. The composition may also contain other components, such as impact modifiers. The invention also relates to articles made from the composition as well as methods of making and using the composition.

Abstract: A spin fluid for producing plexifilamentary products made of a polyolefin dissolved in a primary solvent of dicloromethane or 1,2-dichloroethylene with a straight chain hydrofluorocarbon co-solvent.

Abstract: The poly(phenylene oxide) resin composition of the invention is a poly(phenylene oxide) resin composition containing poly(phenylene oxide) and triallyl isocyanurate, wherein the poly(phenylene oxide) has a number average molecular weight in a range from 2,000 to 12,000 and the IPN structure can be formed in a cured product of the poly(phenylene oxide) and triallyl isocyanurate to provide a high heat resistance, and at the same time by using a poly(phenylene oxide) with a relatively low molecular weight, the fluidity of the melt resin can be made desirable at the time of molding to result in high molding properties.

Abstract: This invention concerns a thermosetting resin system that is useful in the manufacture of high performance prepreg, laminate and composite materials as well as, prepregs, laminates and composites made from the thermosetting resin composition.

Abstract: A hot melt adhesive composition that includes thermoplastic polymer, a source of zinc, at least one of aluminum trihydrate and magnesium hydroxide, and no greater than 70% by weight of a source of halogen. Articles that include a porous substrate and the hot melt adhesive composition.

Abstract: Disclosed are flame retardant compositions comprised of (a) brominated anionic styrenic polymer, and (b) at least one polybrominated alpha-omega diphenylalkane having a total of at least 6 bromine atoms directly bonded to the phenyl rings and in the range of 1 to 6 carbon atoms in the alkylene group disposed between the phenyl groups, and specified flame retarded polymer compositions with which have been blended (a) and (b) individually or in combination.

Abstract: Provided are new flame retardants and liquid flame retardant additive compositions of low viscosity for use in flexible polyurethane foams. The new flame retardants are the reaction product of at least one brominated aromatic diester diol with at least one alcohol-reactive agent. Preferred liquid flame retardant additive compositions are capable of minimizing visible scorching of the foam during its production. Flexible flame retardant polyurethane foams and methods for their production are also provided. The flame retardant additive compositions are formed at least from a) at least one reaction product of a brominated aromatic diester diol and an alcohol-reactive agent; b) at least one hindered amine antioxidant; and c) at least one phenolic antioxidant in which the phenolic ring is substituted by an alkanoic acid alkyl ester group in which alkanoic acid moiety has in the range of 2 to about 4 carbon atoms and the alkyl group has in the range of about 6 to about 16 carbon atoms.

Abstract: Organic polymer substrates, for example polyolefins such as polypropylene, can be made flame retardant by the incorporation of a mixture of (i) at least one melamine based flame retardant and (ii) at least one flame retardant selected from the group consisting of the organohalogen and phosphorus containing flame retardants. Further optional flame retardants include antimony compounds and sterically hindered amines.

Abstract: The invention relates to thermoplastic moulding materials containing A) 10–98 wt. % of at least one thermoplastic polyester, B) 1–30 wt. % of a flame resistant material combination made of 100 wt. % B), b1) 20 99 wt. % of a flame resistant material containing halogen b2) 1–80 wt. % of an antimonoxide, C) 0.01–5 wt. % of tartaric acid or tartrates or a mixture thereof, D) 0 is 5 wt.-% of at least one stabilisator containing phosphorous, E) 0–70 wt.-% of additional materials, whereby the sum of the wt % of the components A)–E) is 100%.

Abstract: The invention relates to thermoplastic molded masses, comprising A) 10 to 97 wt. % of at least one thermoplastic polyester, B) 1 to 30 wt. % of a flame-resistant agent combination with, based on 100 wt. % B), b1) 20 to 99 wt. % of a halogenated flame resistant agent, b2) 1 to 80 wt. % of a antimony oxide, C) 0.01 to 3 wt. % of at least one polyamide, D) 0.01 to 2 wt. % of at least one nigrosin, E) 0.01 to 3 wt. % of at least one anti-dripping agent and F) 0 to 70 wt. % of further adjuncts, whereby the sum of components A) to F) is 100%.

Abstract: The present invention provides novel pentabromobenzyl alkyl ethers serving as highly effective flame retardants in polymers. The invention further provides a fire retarded polymer composition comprising said pentabromobenzyl alkyl ethers.

Abstract: A composition of matter and a solvent system for use in providing a water resistant coating to basement walls is disclosed. The solvent system comprises a chlorinated solvent blend. The solvent system and coating composition have no flash point, are non-flammable and provide an improved consistent coating when applied to walls.

Abstract: The present invention provides a polypropylene resin composition including a polypropylene resin having a melt flow rate of 4-18 g/10 minutes, a flame retardant additive having a low melting point, an antimony oxide, a UV stabilizer, a silane coupling agent, and titanium dioxide as a light-blocking agent. The resin composition of the invention produces products exhibiting excellent flame retarding properties, stability against weather, and maintainability of physical/mechanical properties as shown by maintaining the original flame retarding properties after long periods of outdoor exposure and hydrothermal dipping treatments.

Abstract: A thermoplastic resin composition for an electrical/electronic contact part according to the present invention includes a thermoplastic resin and a polyol, wherein the polyol is contained in a range of 0.2 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin. Alternatively, a thermoplastic resin composition for an electrical/electronic contact part according to the present invention includes: a thermoplastic resin; a halogenated aromatic compound which is contained in a range of 1 to 50 parts by weight based on 100 parts by weight of the thermoplastic resin; and a double salt represented by at least one of (X2O)n.Sb2O5 and (YO)n.Sb2O5, where X represents a monovalent alkaline metal element, and Y represents a divalent alkaline earth metal element, and n represents a ratio of X2O or YO to Sb2O5 exceeding 0.7, the double salt having an adsorbed water elimination rate of not more than 50 min.

Abstract: A hot melt adhesive composition that includes thermoplastic polymer, a source of zinc, at least one of aluminum trihydrate and magnesium hydroxide, and no greater than 70% by weight of a source of halogen. Articles that include a porous substrate and the hot melt adhesive composition.

Abstract: A flame retarding and smoke suppressing additive powder that can be mixed with resins includes a carbonific material, a heat activated blowing agent, a heat activated halogen material, a phosphate material, and an inorganic material. The additive powder, when added to a curable or hardenable resin, forms a mixture where the additive powder is about 20-30%, by weight, of the mixture. The resin can be styrenic, olefinic, acrylic, cellulosic, polyester, or polyamide such as are commonly used in the manufacture of fiberglass reinforced structures and moldable plastics.

Abstract: Polyolefin-based pallets capable of passing standard pallet flammability tests are prepared by molding the pallet or one or more subassemblies thereof, of a polyolefin molding resin containing a flame retardant package containing a halogenated organic flame retardant, alumina trihydrate, and antimony trioxide. The flame retardants are advantageously supplied as a master batch at a concentration higher than that desired in the pallet or subassembly, in a polyolefin-compatible polymer.

Abstract: The flame-retardant polyamide composition of the present invention comprises (A) 20 to 80% by weight of an aromatic polyamide, composed of recurring units of dicarboxylic acid component unit and diamine component unit, the former composed of 30 to 100% by mol of a terephthalic acid component unit and 0 to 70% by mol of an aromatic dicarboxylic acid component unit other than terephthalic acid and/or 0 to 70% by mol of a C4-C20 aliphatic dicarboxylic acid component unit and the latter composed of an aliphatic diamine component unit and/or an alicyclic diamine component unit; and having an MFR of 40 to 300 g/10 minutes, determined at a load of 2,160 g and temperature of 10° C. plus melting point, and melting point exceeding 290° C.; (B) 5 to 50% by weight of an inorganic reinforcing agent, (C) 5 to 40% by weight of a bromine-based flame retardant, containing at least one type of polybrominated styrene obtained by polymerization of brominated styrene, and (D) 0.

Abstract: An insulation material comprising a low-density EPDM polymer, at least one flame-retardant, and an organic filler. The insulation material is used in an insulation layer of a rocket motor. The organic filler is a polymeric, organic filler such as polyvinyl chloride. A rocket motor comprising an insulation material is also disclosed. The insulation material comprises a low-density EPDM polymer, at least one flame-retardant, and a polymeric organic filler and is applied between an inner surface of a case of the rocket motor and a propellant. A method of insulating a rocket motor is also disclosed.

Abstract: Disclosed is a rubber composition for forming a core of a solid golf ball, the composition containing a base rubber (A); a filler (B); an organic peroxide (C); and a dry blend and/or a solvent slurry blend (D) of an unsaturated carboxylic acid metallic salt and a metal-containing organic sulfur compound represented by the following formula (1): (wherein X represents a halogen atom, each of m and n represents an integer of 0 to 5 inclusive, and M represents a divalent metallic atom). The rubber composition exhibits high curing rate, and can be cured within shorter time, whereby productivity of a core can be improved.

Abstract: Thermoplastic molding compositions comprising

Abstract: The present invention relates to a thermoplastic polyester-based flame-retardant resin composition comprising (A) 100 parts by weight of a thermoplastic polyester resin, (B) 3 to 50 parts by weight of a bromine-containing aromatic compound, (C) 2 to 30 parts by weight of an antimony oxide compound, (D) 0.1 to 3 parts by weight of polytetrafluoroethylene having fibril-forming abilities, and (E) 0.7 to 8 parts by weight of a lamellar filler.

Abstract: The polyamide resin composition of the invention is characterized by having a solder reflow heat-resistant temperature of not lower than 250° C. Since the polyamdie resin composition has low water absorption and is excellent in moldability, heat resistance, shape stability and mechanical strength, it can be suitably used for, for example, automobile parts and electric or electronic parts.

Abstract: The present invention provides a flame retardant resin composition, or more particularly, a flame retardant polypropylene resin composition which comprises polypropylene having improved flow melt characteristics, flame retardants, a flame retardant aid, and a tetrafluoroethylene polymer. The composition of the present invention has high melt tension, without deterioration of the mechanical properties of flame retardant polypropylene, and drastically enhanced characteristics of shape maintenance and a flaming drip during burning.

Abstract: Polymeric substrates, for example polyolefins such as polypropylene, can be made flame retardant by the incorporation therein of a synergistic mixture of (i.) at least one compound selected from the group consisting of nitroxyl stabilizers, hydroxylamine stabilizers, nitrone stabilizers, substituted hydroxylamine stabilizers, amine oxide stabilizers, benzofuranone stabilizers phosphite and phosphonite stabilizers, quinone methide stabilizers and monoacrylate esters of 2,2′- alkylidenebisphenol stabilizers and (ii.) at least one compound selected from the group consisting of brominated flame retardants, phosphorus containing flame retardants and inorganic flame retardants such as ammonium polyphosphate or decabromodiphenyl oxide; wherein the amount of organic or inorganic flame retardant of component (ii.) required to achieve an acceptable level of flame retardancy is significantly reduced compared to that needed when component (i.) is not present.

Abstract: The invention provides a curing agent for two-pack type curable composition use having excellent storage stability, and also provides a curing agent composition which comprises a hydrolyzable silyl group-containing compound (a), a non-phthalic acid ester based plasticizer (b) having no phthalic acid ester structure in its molecule, and a bivalent tin based curing catalyst (c), that satisfies all of mechanical properties, recoverability and adhesiveness to substrate, can be mixed easily when used and has excellent storage stability, and a two-pack type curable composition which hardens when a base resin composition comprising a curable organic polymer (d) having in its molecule a functional group crosslinkable by a reaction catalyzed by a bivalent tin based curing catalyst (c), an epoxy group-containing silane compound (f) and an epoxy compound (g) is mixed with the above curing agent composition.

Abstract: An electronic device for high frequency signals having a small dielectric loss and high efficiency is provided which has a low dielectric loss tangent resin composition for coping with high frequency signals as an insulating layer.

Abstract: The present invention provides a process of hydrogenating a nitrile copolymer rubber, which comprises subjecting the copolymer to hydrogenation in the presence of a hydrogenation catalyst, a co-catalyst, and a proton acceptor that is non-coordinating with the metal-complex catalyst.

Abstract: Provided are flame retardant coating compositions and articles coated therewith, which compositions comprise (A) a coating and (B) an effective flame retarding amount of a mixture of (i) at least one compound selected from the group consisting of the (a) sterically hindered nitroxyl stabilizers, (b) sterically hindered hydroxylamine stabilizers and (c) sterically hindered alkoxyamine stabilizers and (ii) at least one conventional flame retardant selected from the group consisting of (d) organohalogen flame retardants, (e) organophosphorus flame retardants, (f) isocyanurate flame retardants and (g) melamine based flame retardants. The coated articles are for example iron, steel, stainless steel, aluminum and other non-ferrous metals, wood, plywood, paper, cardboard, chip board, particle board, plastics, thermoplastics, epoxies, neoprene, rubber, composites, fiberglass reinforced composites, polyesters, polymeric foam, masonry, fabric or textiles, wire and cable constructions and circuit boards.

Abstract: A composite reinforced thermoplastic sheet comprising a thermoplastic sheet and a fabric reinforcing layer adhered thereto, wherein the thermoplastic sheet comprises a polymer blend of ethylene-styrene interpolymer, polyolefin, and thermoplastic rubber and at least one fire retardant.

Abstract: Organic polymeric substrates, for example polyolefins such as polypropylene, can be made flame retardant by the incorporation of a synergistic mixture of (i) at least one low molecular weight sterically hindered alkoxyamine stabilizer, (ii) at least one high molecular weight sterically hindered alkoxyamine stabilizer and (iii) at least one conventional flame retardant selected from the group consisting of the organohalogen, phosphorus containing and melamine based flame retardants. The compositions of the invention combine good flame retardant properties with light stability and good mechanical properties. Polyolefin molded articles are stabilized against light, heat and oxygen and made flame retardant with the incorporation of at least one sterically hindered alkoxyamine and at least one conventional flame retardant, while allowing normally high levels of flame-retardant fillers to be greatly reduced or eliminated.

Abstract: A lap edge sealant composition is provided for adhering together overlapping sheets of roofing material which includes a rubbery polymer such as EPDM, a thermoplastic rubber, a tackifier, and a solvent, where the solvent is selected from aliphatic hydrocarbons, para-chlorobenzotrifluoride, or blends thereof. The lap edge sealant has a high solids content of about 65 to 90%, a volatile organic compound (VOC) content of less than about 250 g/l, and exhibits no more than about 35% shrinkage upon curing.

Abstract: Flame retardant additive compositions having enhanced thermal stability are described. They comprise a blend formed from (A) at least one organic bromine flame retardant selected from (i) a flame retardant compound having a plurality of bromine atoms directly bonded to a cycloaliphatic ring, (ii) the bis(2,3-dibromopropyl ether) of tetrabromobisphenol-A, and (iii) the bis(2,3-dibromopropyl ether) of tetrabromobisphenol-S, (B) an alkyltin mercaptoalkanoate, and (C) a zeolite adjuvant. The proportions are 0.01-0.08 part by weight of (B) per part by weight of (A), and 0.01-0.35 part by weight of (C) per part by weight of (A). Thermoplastic polymer compositions in which these additive compositions are employed possess enhanced properties.

Abstract: Flame-retarded transparent plastic compositions comprising polyhalgenated trimethylphenyl indan. The polyhalogenated trimethylphenyl indan is a mixture of polyhalogenated trimethylphenyl indanes having each 3 to 9 halogen atoms. The halogen may be bromine or a mixture of bromine and chlorine. The transparent plastic is selected from polycarbonate, polymethylmethacrylate, and polystyrene. The polyhalogenated trimethylphenyl indan is present in an amount of up to about 40% by weight. The transparent plastic flame-retarded material is prepared by mixing the plastic matrix with a flame-retardant effective amount of a polyhalogenated trimethylphenyl indan.

Abstract: Fire retardant sheeting materials for roofing having improved burn resistivity and are suitable for use on roofs having inclines of at least 1 inch per linear foot. These sheeting materials are prepared from a polymeric composition of matter comprising a base polymer containing at least one ethylene-propylene-diene terpolymer, the base polymer having up to about 2 percent by weight crystallinity; from about 85 to about 175 parts by weight of at least one non-combustible mineral filler per 100 parts of the base polymer; from about 30 to about 50 parts by weight of a processing material, per 100 parts of the base polymer; from about 50 to about 80 parts by weight of at least one fire retardant additive, per 100 parts of the base polymer; and from about 1.5 to about 10 parts by weight of a sulfur cure package per 100 parts of the base polymer.

Abstract: The object of the invention is to provide sound insulating members exhibiting both high vibration damping performance and high sound insulation performance, a vibration damping material for affording such members and a resin composition for forming the vibration damping material. The invention provides a first resin composition for vibration damping materials which contains 100 parts by weight of a chlorine-containing thermoplastic resin, and 20 to 200 parts by weight of a chlorinated paraffin having 12 to 16 carbon atoms on average. The thermoplastic resin contains preferably 20 to 70 wt. %, more preferably 30 to 70 wt. %, of chlorine. The chlorinated paraffin is preferably 30 to 70 wt. %, more preferably 35 to 65 wt. %, in chlorination degree.

Abstract: A liquid chemical formulation suitable for making a thin solid polycarbonate film contains polycarbonate material and a liquid typically capable of dissolving the polycarbonate material to a concentration of at least 1%. The polycarbonate material may consist of homopolycarbonate or/and copolycarbonate. Examples of the liquid include pyridine, a ring-substituted pyridine derivative, pyrrole, a ring-substituted pyrrole derivative, pyrrolidine, a pyrrolidine derativive, chlorobenzene, and cyclohexanone. A liquid film (36A) of the formulation is formed over a substructure (30) and processed to remove the liquid. The resultant solid polycarbonate film can later serve as a track layer through which charged particles (70) are passed to form charged-particle tracks (72). Apertures (74) are created through the track layer by a process that entails etching along the tracks. The aperture-containing polycarbonate track layer is typically used in fabricating a gated electron-emitting device.

Abstract: Herein is disclosed a flame-retarded thermoplastic resin composition which comprises an original flame-retarded thermoplastic resin composition comprising certain amounts of a thermoplastic resin and of a brominated flame-retardant, and, in combination therewith, a certain amount of a dolomite compound, or in addition thereto, a certain amount of at least one compound selected from a hydrotalcite, a zinc-substituted hydrotalcite compound, or a zeolite compound, which flame-retarded thermoplastic resin composition of the present invention are remarkably improved in heat stabilizing effects as compared with the original flame-retarded thermoplastic resin composition.

Abstract: A cationically polymerizable resin composition which comprises (A) a compound containing at least one ring selected from the group consisting of an oxirane ring and an oxetane ring; (B) an onium salt; (C) an organic peroxide; and (D) an alkaline filler except for a hydroxide.

Abstract: The flame retardant additive compositions comprise (a) one or more bromocycloaliphatic flame retardants; (b) one or more bromoaromatic flame retardants; and (c) one or more synthetic zeolites. Flame retardant polymer compositions comprising at least one thermoplastic polymer such as HIPS with which has been blended, singly and/or in one or more combinations, a flame retardant amount of at least (a), (b), and (c) have a very desirable balance of properties.

Abstract: Disclosed are a resin composition comprising an ethylene-vinyl alcohol copolymer and a multi-layered structure comprising the resin composition. The resin composition comprises an ethylene-vinyl alcohol copolymer which contains from 500 to 2000 ppm, in terms of the metal, of an alkali metal salt (A) and from 0.05 to 4.5 &mgr;mols/g of a carboxylic acid (B), where the ratio of the content (&mgr;mol/g) of a carboxylic acid (b1) having a molecular weight of at least 75 and its salt to the total content (&mgr;mol/g) of the carboxylic acid (B) and its salt is at least 0.1; or comprises an ethylene-vinyl alcohol copolymer which contains from 500 to 2000 ppm, in terms of the metal, of an alkali metal salt (A), from 10 to 500 ppm of a carboxylic acid (b2) having a molecular weight of smaller than 75, and from 10 to 500 ppm, in terms of the phosphate radical, of a phosphate compound (C). The resin composition has extremely good adhesiveness, and its moldings have good appearances with few gels and fish eyes.

Abstract: This invention relates to thermoplastic polymer compositions comprising a clay having drip resistance in the Underwriters Laboratories Standard 94 flammability test.

Abstract: The object of the present invention is to provide a flame-retardant resin composition which has a high heat resistance, superior impact resistance and superior flame-retarding properties. The present invention provides a flame-retardant resin composition which is characterized by the fact that said composition contains (A) a polycarbonate type resin, (B) a silicone resin constructed from siloxane units expressed by the formula RSiO1.5 (T units) and siloxane units expressed by the formula R3SiO0.5 (M units), or a silicone resin constructed from T units, M units and siloxane units expressed by the formula SiO2.0 (Q units) (R indicates an unsubstituted or substituted monovalent hydrocarbon group with 1 to 10 carbon atoms), and (C) an anti-drip agent, and the aforementioned composition contains 0.1 to 9 parts by weight of the abovementioned silicone resin (B), and 0.01 to 10 parts by weight of the abovementioned anti-drip agent, per 100 parts by weight of the abovementioned polycarbonate resin (A).

Abstract: A flame-retardant thermoplastic resin composition, which comprises a polymer alloy composed of a thermoplastic resin (A) and a liquid-crystal polymer (B), is excellent in the stability of the heat retentivity imparted thereto in the injection molding step, exhibits an extremely high reinforcing effect which has been unattainable heretofore because the liquid-crystal polymer can be readily fiberized in the molding step, and provides moldings excellent in flame retardancy.

Abstract: The flame-retardant polyamide composition of the present invention comprises (A) 20 to 80% by weight of an aromatic polyamide, composed of recurring units of dicarboxylic acid component unit and diamine component unit, the former composed of 30 to 100% by mol of a terephthalic acid component unit and 0 to 70% by mol of an aromatic dicarboxylic acid component unit other than terephthalic acid and/or 0 to 70% by mol of a C4 - C20 aliphatic dicarbolic acid component unit and the latter composed of an aliphatic diamine component unit and/or an alicyclic diamine component unit; and having an MFR of 40 to 300 g/10 minutes, determined at a load of 2,160 g and temperature of 10° C. plus melting point, and melting point exceeding 290° C.

Abstract: A polybutadiene composition comprising a polybutadiene type polymer and a compound represented by the following formula (I): 1

Abstract: In the present invention, the No. I invention relates to a regenerated PET resin composition which comprises formulating 0.5-100 part by weight of a lactone polymer (B) with 100 parts by weight of a regenerated PET resin (A), in which there is improved a molding processability such as an injection moldability and extruding molding, and relates to a molded article therefrom and, the No. II invention relates to a flame retardant resin composition containing a thermoplastic resin (E) and a flame retardant (F), in which bleeding of the flame retardant is suppressed without a decline of a flame retardancy, and relates to a molded article therefrom.

Abstract: The polyester resin composition of the present invention comprises (A) a thermoplastic polyester resin, (B) an olefinic polymer modified with at least one member selected from the group consisting of an unsaturated carboxylic acid and its derivative, and (C) an aliphatic ester having a molecular weight of 400 to 1,000. The polyester resin of the present invention may comprises: (D) a flame retardant, (E) an inorganic flame retardant auxiliary, and others. The thermoplastic polyester resin composition is useful for the fabrication of sliding members (particularly, gears). Polyester resin compositions with improved dimensional accuracy and sliding properties and shaped articles formed therefrom can be obtained from the resin composition of the present invention.

Abstract: A spinning process using azeotropic compounds as spin agents having essentially zero ozone depletion potential and that are either non-flammable or of very low flammability.

Abstract: This invention pertains to the art of solvent blends and solvent/resin blends. More particularly, this invention pertains to blends that reduce the atmospheric reactivity of some high volatile organic compounds. The invention is particularly applicable to solvent blends and solvent/resin blends that combine volatile organic compounds with newly discovered zero volatile organic compounds for use adhesives, coatings, inks, cleaning and blowing agents and the like and will be described with particular reference thereto. However, it will be appreciated that the invention may be advantageously employed in other environments and applications.

Abstract: A conveying system comprising an upfeed conveyor for conveying individual stock items upwardly to a press or the like and a generally horizontal infeed conveyor for conveying endwise a stack of items positioned on edge thereon to the upfeed conveyor which has several sections all of which are activated to move the item delivered thereto upwardly and wherein the lower sections are periodically stopped and the uppermost section is freely adapted to move to facilitate withdrawal of the item in transit from the upfeed conveyor, the infeed conveyor being vertically adjustable and tiltable with respect to the upfeed conveyor for handling different sized stock items, and wherein conveyors are so juxtaposed that the item in transit on the upfeed conveyor shields the upper portion of the next item from engaging movable section until the item in transit is completely withdrawn from the upfeed conveyor and wherein a retard is provided with an items gauge shield to insure single item feeding.