Abstract: A stabilizer mixture containing

Abstract: Flame retardant compositions useful as insulation for 150° C.-rated wire and cable applications are provided. The compositions of the invention utilize an ethylene-alkyl acrylate copolymer base resin with a two-component stabilizer package consisting of a zinc salt of a mercaptobenzimidazole and an aromatic secondary amine compound. Also, included to achieve the requisite flame retardance, crosslinkability and physical properties are a brominated flame retardant, antimony trioxide, a hydrated inorganic filler and a chemical crosslinking agent.

Abstract: Self-extinguishing cable coated with a flame-retardant composition having: (a) an ethylene homopolymer or copolymer having a density of from 0.905 to 0.970 g/cm3, and being selected from: ethylene homopolymers: copolymers of ethylene with an alpha-olefin; copolymers of ethylene with an ethylenically unsaturated ester; or mixtures thereof; (b) a copolymer of ethylene with at least one alpha-olefin, and optionally with a diene, said copolymer (b) having a density of from 0.860 to 0.904 g/cm3, and having a composition distribution index greater than 45%; (c) natural magnesium hydroxide in an amount such as to impart flame-retardant properties; wherein at least one of the polymeric components (a) and (b) contains hydrolyzable organic silane groups grafted onto the polymer chain. The silane groups are preferably introduced during compounding of the flame-retardant composition by adding to the polymer mixture a suitable silane compound and a radical initiator.

Abstract: Polyesters may be prepared by reacting an amyl diiodide, an aliphatic or aryl diol and carbon monoxide in presence of a catalyst and an organic base. The process is preferentially carried out in a solvent. The catalyst is a heterogeneous catalyst containing a metal selected from a group containing Palladium, Platinum, Nickel and Cobalt. Following the formation of polyester, the catalyst can be easily separated and efficiently recycled.

Abstract: An ingot support device for slicing silicon is produced by molding a molding material obtained by blending an acrylic resin or an unsaturated polyester resin and one or more inorganic fillers selected from the group consisting of aluminium hydroxide, barium sulphate, barium carbonate, calcium carbonate and silica. According to the present invention, there is provided an ingot support device for slicing silicon which can be produced easily at a low cost, which has enough strength to cope with the upsizing of the ingot block, has high adhesive properties with the ingot block, and has other further improved properties which are required of the ingot support device for slicing silicon.

Abstract: An aqueous coating composition comprising a fluororubber and, as an acid acceptor, at least one inorganic composite compound, for example, an inorganic composite oxide or an inorganic composite salt, in particular, an inorganic composite compound containing magnesium such as a hydrotalcite. Such an inorganic composite compound is not agglomerated to form secondary particles, when it is dispersed to primary particles, and can maintain the storage stability of the aqueous coating composition of a fluororubber.

Abstract: A coating substance with a low emissivity or high reflectivity in the heat radiation wavelength range. A binder with high transparency in the heat radiation range, especially in the range of wavelengths from 3 to 50 &mgr;m, contains particles having a high transparency in this range and the refractive index of which in the heat radiation wavelength range differs from that of the binder.

Abstract: The present invention relates to a semiconductor encapsulating resin composition which is safe and superior in moisture resistance, flame retardance and moldability, and to a highly reliable semiconductor device which is fabricated by encapsulating a semiconductor element with such a semiconductor encapsulating resin composition. The resin composition according to the present invention comprises a thermosetting resin, a hardening agent and a compound metal hydroxide of polyhedral crystal form represented by the following general formula (1): m(MaOb).n(QdOe).cH2O  (1) [wherein M and Q are different metal elements; Q is a metal element which belongs to a group selected from IVa, Va, VIa, VIIa, VIII, Ib and IIb groups in the periodic table; m, n, a, b, c, d and e, which may be the same or different, each represents a positive number].

Abstract: Adhesives comprising as binder an aqueous dispersion of a polymer formed from free-radically polymerizable compounds (monomers), wherein from 0.1 to 20% by weight of the monomers, based on the overall amount of the monomers, are ethylenically unsaturated acids at least 20 mol % of whose acid groups are present as a salt of at least divalent metals.

Abstract: A polypropylene resin composition comprising 100 parts by weight of a polypropylene resin, 0.001 part by weight or more and less than 0.03 parts by weight of an alkaline earth metal hydroxide and 0.01 part by weight or more and less than 0.5 parts by weight of a phenol antioxidant, a molded product and a film prepared therefrom. The composition is excellent in thermal stability, makes less dirty a processing machine on processing and is less fuming.

Abstract: A flame retardant composition suitable for mesh sheets comprising 1.5 to 15 parts by weight of red phosphorus, 5 to 50 parts by weight of melamine sulfate, 40 to 150 parts by weight of a metal hydroxide, and a polyolefin-based resin aqueous dispersion having a resin solid content of 25 to 70% by weight. Each of said weights being based upon 100 parts by weight of the solid content of said dispersion. The present invention in many embodiments does not contain halogen, does not experience a rise in the viscosity of flameproofing agent during storage and provides an excellent effect that the flameproofing component does not elute even when a treated mesh sheet is washed and used repeatedly.

Abstract: A synthetic resin composition having heat deterioration resistance comprising: (A) 100 parts by weight of a synthetic resin; and (B) 0.001 to 10 parts by weight of hydrotalcite particles defined by the following (i) to (iv): (i) the hydrotalcite particles are represented by the following chemical structure formula (1): {(Mg)y(Zn)z}1−x(Al)x(OH)2(An−)x/n.mH2O  (1); (ii) the hydrotalcite particles have an average secondary particle diameter of 2 &mgr;m or less; (iii) the hydrotalcite particles have a specific surface area (measured by a BET method) of 1 to 30 m2/g; and (iv) the hydrotalcite particles contain an iron compound and a manganese compound in a total amount of 0.02 wt % or less in terms of metals (Fe+Mn). A molded article formed from the above resin composition of the present invention is excellent in heat deterioration resistance and impact resistance and satisfactory in the dispersibility of hydrotalcite particles.

Abstract: Aqueous dispersions of cationic water-soluble polymers are provided, as well as processes for making and methods of using the same.

Abstract: Compositions containing, per 100 parts by weight polyphenylene sulphide: 10 to 300 parts by weight of a polyamide, and 20 to 350 parts by weight of a metal hydroxide in which the main constituent is magnesium hydroxide. In addition, they preferably contain 20 to 500 parts by weight of a fibrous reinforcing material.

Abstract: A coagulant which is the reaction product of a trivalent metal salt (eg., FeCl3), excluding chromium salts, an acid phosphorous compound and an aluminum hydroxy chloride, and a process for preparing such coagulant. This coagulant may be effectively used to remove suspended solids and various impurities in most water treatment applications.

Abstract: A flame-retardant polyolefin-type resin composition comprising (A) 100 weight parts polyolefin-type resin, (B) 30 to 200 weight parts powder of a hydrated metal compound, and (C) 0.01 to 50 weight parts branched organopolysiloxane with average unit formula RaSiO(4−a)/2 where each R is a selected from the group consisting of monovalent organic groups selected from the group consisting of C1 to C12 alkyl and C6 to C12 aryl and hydroxyl, wherein aryl constitutes from 50 to 100 mole % of the total monovalent organic groups and the hydroxyl content in each molecule is from 1 to 10 weight %, a is a number from 0.75 to 2.5, and the organopolysiloxane contains at least one RSiO3/2 siloxane unit in each molecule, where R is as previously described. The composition is useful as a flame-retardant coating on electrical cables.

Abstract: Disclosed is a vulcanizable fluororubber composition comprising (a) a tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer, (b) an organic peroxide, (c) a co-crosslinking agent and (d) hydrotalcite. The copolymer (a) preferably contains an iodine atom or a bromine atom. The vulcanizable fluororubber composition preferably further comprises carbon black or titanium oxide. When the vulcanizable fluororubber composition is vulcanized, the resulting vulcanizate has excellent compression set and is relatively non-toxic.

Abstract: The present invention provides a metal salt-containing resin composition, which comprises (a) a hydrophilic polymer which is a polymer or copolymer of an ethylene oxide-containing monomer, and (b) 0.1 to 30% of a metal salt, based on the weight of the hydrophilic polymer. The resin composition of the present invention has long lasting antistatic properties and a lower surface resistivity than the hydrophilic polymer alone.

Abstract: There are provided a flame retardant comprising hydrotalcite compound particles which exhibits excellent heat deterioration resistance when it is used as a flame retardant for resins, a resin composition comprising the same and a molded article thereof. There are also provided a heat deterioration resistant flame retardant comprising hydrotalcite compound particles which (i) have an average secondary particle diameter, measured by a laser diffraction scattering method, of 2 &mgr;m or less and (ii) contain an iron compound and a manganese compound in a total amount of 0.02 wt % or less in terms of metals, a synthetic resin composition comprising the same and a molded article thereof.

Abstract: Abrasive jet stream polishing, wherein an abrasive is suspended in a flowable jet medium and projected at high velocity and pressure at a workpiece is provide, where the jet is projected at the surface to be polished at an oblique angle. The method is substantially improved by forming the medium of a polymer having reformable sacrificial chemical bonds which are preferentially broken under high shear conditions. Projecting the medium and suspended abrasive breaks the reformable sacrificial chemical bonds while polishing. The chemical bonds will reform, permitting recycling of the medium and abrasive for reuse in the method. The jet is effective at relatively low pressures of about 5 to about 80 MPa.

Abstract: A flame retardant resin composition for electrical insulation and sheathing of wire and cables which has enhanced oil resistance and excellent processing characteristics, comprising (a) 100 parts by weight of a polyolefin polymer, (b) 50 to 200 parts by weight of a metal hydroxide or hydrated metal salt, (c) 3 to 20 parts by weight of a polyolefin based polymer or oligomer grafted or copolymerized with a vinyl bearing species, where polyolefin based polymer (c) differs from polyolefin polymer (a), and (d) 1 to 10 parts by weight of a silicone compound.

Abstract: An inkjet printing coating compositions and recording sheets having printable coating compositions on substrates which are suitable for photographic quality prints by inkjet printing technology, such as thermal and piezo. The recording sheet which comprises a substrate and a dried coating composition on the substrate, which coating composition comprises either (i) a hydrophilic or amphiphilic polyether polyurethane plus one or more polymers selected from the group consisting of cellulose ester polymers, cellulose ether polymers and vinyl polymers or (ii) cellulose acetate trimellitate plus optionally one or more polymers selected from the group consisting of cellulose ester polymers, cellulose ether polymers and vinyl polymers; a quaternary ammonium compound; a metal salt chelating agent; and a microcrystalline filler drying agent.

Abstract: A process for stabilizing a halogen-containing plastic against thermal or photochemical degradation by adding to the plastic an additive consisting essentially of cationic layer compounds corresponding to general formula (I): [M(II)xAl(OH)y](An−)z.mH2O  (I) where M(II) represents at least one divalent metal ion and An− represents an acid anion having the charge n−(n=1, 2 or 3) and 1<x<5, y>z, (y+nz)=2x+3 and 0<m<10, and wherein the cationic layer compounds have been prepared by adding alkali metal hydroxide to a water-containing mixture of at least one source of divalent metal ions M(II), one source of the anion An− and crystalline aluminum hydroxide in a quantity of 1 to 20 mole-%, based on aluminum hydroxide, heating the mixture for 10 to 240 minutes at a temperature of 100° C. to 240° C., and drying the mixture to form a powder without previous separation of the solid from the aqueous phase.

Abstract: Aqueous dispersions of cationic water-soluble polymers are provided, as well as processes for making and methods of using the same. The cationic polymers contain anionic recurring units in amounts that encourage the formation of the aqueous dispersion and/or advantageously reduce the bulk viscosity of the aqueous dispersion.

Abstract: The present invention relates to compositions having enhanced ignition resistance, comprising: (A) from about 5 to about 90 percent by weight of at least one substantially random interpolymer; (B) from about 10 to about 94.9 percent by weight of at least one filler selected from ammonium polyphosphate, magnesium hydroxide, calcium hydroxide, and aluminum trihydrate; and (C) at least one component selected from; (1) about 5 to about 50 percent by weight of at least one filler; or (2) about 0.5 to about 20 percent by weight of at least one metal borate, and, optionally, about 0.5 to about 10 percent by weight of at least one processing aid; or (3) about 0.1 to about 15 percent by weight of at least one initiator or at least one coupling agent; or (4) about 0.1 to about 20 percent by weight of at least one hindered amine stabilizer.

Abstract: A formulation based on polyvinyl chloride compounds (PVC) particularly to high mechanical resistance compounds, specially with regard to abrasion. The composition does not have heavy metal based stabilizers and is used for insulation of thin wall automotive primary cable. The present invention includes a process to prepare said formulation.

Abstract: A flame retardant suitable for use in mesh sheets comprising a polyolefin resin aqueous dispersion having a resin solid content of 25-75 wt %, 40 to 130 parts by weight of an ammonium polyphosphate compound based on 100 parts by weight of said polyolefin resin aqueous dispersion, and 60 to 150 parts by weight of a metal hydroxide based on 100 parts by weight of the solid content of said polyolefin resin aqueous dispersion.

Abstract: An infrared absorber which comprises containing as an effective ingredient a hydroxide complex salt represented by the formula [Al2(Li(1−x).+M2+(x+y)(OH)(6+2y)]n(An−)(1+x).mH2O (wherein M2+ is a divalent metal, An− is an anion having a valence of n, and m, x and y are numbers respectively in the ranges of 0≦m<5, 0.01≦x≦0.5 and 0≦y≦0.5), which has a high ability to absorp infrared rays and a refractive index close to that of the resin so that it has a good dispersibility with the resins when incorporated in the resin and the shaped film therefrom is excellent in the heat insulation property and transparency so that it is suitable as an agricultural film.

Abstract: In PVC polymer formulations for sheathing for electric wires and cables, it has been determined that antimony trioxide and divalent metal (e.g. zinc) stannate or hydroxystannate cat provide a synergistic flame-retardant additive combination. In this invention, polymer formulations using this flame-retardant additive combination contain not more than 1.5 wt. % of antimony trioxide.

Abstract: Oxyhalopolymer composites which include an oxyhalopolymer having free volume therein and an inorganic or organic material disposed in the free volume of the oxyhalopolymer are disclosed. Also disclosed is a surface-oxyhalogenated non-halopolymer composite. The composite includes a surface-oxyhalogenated non-halopolymer having free volume therein and an inorganic or organic material disposed in the free volume of the surface-oxyhalogenated non-halopolymer. Methods for making and using these composites are also described.

Abstract: A flame retardant composition comprising (A) about 50 to about 95 percent by weight of at least one ethylene co-polymer selected from an ethylene/vinyl ester copolymer; ethylene/alpha, beta unsaturated carboxylate copolymer; and very low density ethylene/alpha-olefin copolymer; and (B) about 5 to about 50 percent by weight of an ethylene/alpha-olefin copolymer having been prepared with a single site catalyst, and, for each 100 parts by weight of component (A) and component (B) combined, (C) about 2 to about 50 parts by weight of a polyethylene modified with a functional group containing compound; (D) about 5 to about 250 parts by weight of a metal hydrate; (E) about 1 to about 12 parts by weight of a triazine ring containing compound; and (F) about 0.5 to about 5 parts by weight of a flame retardant compound selected from the group consisting of a boron compound, a molybdenum compound, and a silicone.

Abstract: A nanocomposite structure comprising a nanostructured filler or carrier intimately mixed with a matrix, and methods of making such a structure. The nanostructured filler has a domain size sufficiently small to alter an electrical, magnetic, optical, electrochemical, chemical, thermal, biomedical, or tribological property of either filler or composite by at least 20%.

Abstract: Energy dissipating soft polyurethane elastomeric compositions containing any compound that may be magnetically or electro-magnetically aligned to define useful permanent magnetic fields and which may also contain, where desirable, a light-weight filler, are formed by the reaction of an urethane forming polyol containing at least four urethane forming reactive sites and capable of forming stable complexes through free-radicle urethane forming reactive sites, an elasticizing polyol selected from the group comprising diols and triols and a diisocyanate in less than stoiciometric equivalents and resulting in compositions having densities from about 1.2 to 3.8 grams per cc, a compression set of less than 5%, a recovery time of between 10 to about 200 milliseconds and surface hardness of less than about 70 when measured on the Shore 00 scale.

Abstract: An inkjet printing coating compositions and recording sheets having printable coating compositions on substrates which are suitable for photographic quality prints by inkjet printing technology, such as thermal and piezo. The recording sheet which comprises a substrate and a dried coating composition on the substrate, which coating composition comprises either (i) a hydrophilic or amphiphilic polyether polyurethane plus one or more polymers selected from the group consisting of cellulose ester polymers, cellulose ether polymers and vinyl polymers or (ii) cellulose acetate trimellitate plus optionally one or more polymers selected from the group consisting of cellulose ester polymers, cellulose ether polymers and vinyl polymers; a quaternary ammonium compound; a metal salt chelating agent; and a microcrystalline filler drying agent.

Abstract: An organohalide-flame retardant polymer containing as a stabilizer blend: a) an acid scavenger, for example a hydrotalcite or an amorphous basic aluminum magnesium carbonate; b) a heat stabilizer comprising an organotin compound; and c) a polyhydroxyaliphatic costabilizer.

Abstract: An acid-resistant, thermoplastic resin composition which is nonpoisonous and non-halogen and has an acid-resistance for a long period of time, the acid-resistant, thermoplastic resin composition containing a thermoplastic resin, 30 to 70% by weight of magnesium hydroxide which has a specific surface area of 20 m2/g or less and an average secondary particle diameter of 0.2 to 5.0 &mgr;m and is surface-treated with at least one surface-treating agent selected from a water-soluble silane-coupling agent, a phosphoric acid ester, a higher fatty acid or its alkali metal salt, and 1 to 20% by weight of a reaction type compatibilizing agent.

Abstract: A polyisocyanate-based polymer having dispersed therein a metal salt, obtained by reacting an organic polyisocyanate with an aqueous composition of a metal salt. The polymer comprises the metal salt in an amount of from at least 10 weight percent based on total weight of the dry salt with the weight of the polyisocyanate-based polymer including salt therein. The polymer on calcination provides a metal-containing powder having an average particle size of 1 micrometer or less. Such metal-containing powders are of value in the preparation of industrial catalysts, ceramics, electronic components, or as fillers in plastics, paints, or cosmetics.

Abstract: Thin flame resistant solid surface material is provided from compositions containing an acrylic polymer matrix having dispersed therein controlled amounts of magnesium hydroxide as filler, antimony oxide and a brominated flame retardant.

Abstract: Improved flame retardant compositions suitable for insulating wire and cable products comprised of ethylene-alkoxy silane copolymer, halogenated organic compound, antimony trioxide, silane condensation catalyst and magnesium hydroxide are provided. Additionally, antioxidant(s), other mineral fillers and other conventional compounding ingredients may be included in the formulations. The compositions have good processability and are capable of being cured under ambient conditions to provide products which meet all of the specifications of SAE J-1128 for thin wall crosslinked polyolefin low tension primary cable insulation. Wire and cable products comprising a metal conductor coated with from 2 to 100 mils of the flame retardant insulation are also disclosed.

Abstract: A printing resin film excellent in ink dryability and transferability, and comprising a resin composition comprising (A) from 25 to 65% by weight of a calcium carbonate powder having an oil absorption of from 70 to 200 ml/100 g as determined by JIS-K5101-1991 and (B) from 35 to 75% by weight of a thermoplastic resin.

Abstract: Moldable intumescent thermoplastic elastomer materials are disclosed based on suitable proportions of polyethylene, chlorinated polyethylene and a silicone elastomer with silphenylene siloxane monomer moieties and stabilizers, all with foamers, char formers and fillers. Examples of suitable silphenylene-siloxane monomer moieties are 1,4-phenylene-hexamethyltrisiloxanyl and 1,4-phenylene-1,1,3,5,5-pentamethyl-3-vinyltrisiloxanyl where the respective methyl groups may be replaced with suitable phenyl groups or other lower alkyl groups and their fluorinated analogs.

Abstract: A branched polyester resin of the Formula wherein n and m represent randomly repeating segments, and the number of n and m segments in the polymer backbone are each of from about 10 to about 10,000; X is an alkylene group, an olefinic group, or an arylene; Y is an organic dioxy group or radical of I, II, or mixtures thereof; Z is an organic trioxy radical of III, IV, or mixtures thereof; and wherein R and R1 is a hydrogen atom or an alkyl group; G is an alkylene or arylene group, and a is 0 or 1.

Abstract: A polymer composition and fiber, film and fabric prepared therefrom. The composition contains (i) an acid neutralizing agent other than a metallic salt of a saturated or unsaturated fatty acid, (ii) a processing aid comprising a metallic salt of a saturated or unsaturated fatty acid, the metallic salt of a saturated or unsaturated being present in a maximum amount of 200 ppm, a stabilizer system containing (a) a phosphite selected from the group consisting of 2,2′,2″-nitrilo[triethyl-tris(3,3′,5,5′-tetra-tert.butyl-1, 1-biphenyl-2,2′-diyl)phosphite] and tris(2,4-di-tert-butylphenyl) phosphite; and (b) a N,N-dialkylhydroxylamine. Also disclosed is a method for preparing a polyolefin fiber, film or fabric which includes (A) incorporating the above additives into an olefin polymer, thereby producing a stabilized polyolefin polymer; and (B) extruding the stabilized olefin polymer through a die, thereby producing a olefin polymer fiber or film.

Abstract: A method for making a particulate filled polymeric matrix composite film includes mixing a polymeric matrix material with a dispersion of particulate filler in a carrier liquid to form a casting composition and adjusting the viscosity of the casting composition to retard separation of the particulate filler from the composition. A layer of the viscosity-adjusted casting composition is cast on a substrate and the layer is consolidated to form the particulate filled polymer matrix composite film. Films made by the method include very thin, e.g less than 1.0 mil, fluoropolymeric matrix films highly filled with very small diameter, preferably spherical, particles for use as, e.g. dielectric substrate materials in laminar electrical circuits.

Abstract: Provided are water-dispersible sulfopolyester compositions having relatively large proportions of pigments and/or fillers. Such compositions are useful as packaging materials and are substantially non-blocking when processed using packaging rolls and are comprised of at least one sulfopolyester as described herein, about 10 to about 75 weight percent of a pigment and/or filler, and a wax.

Abstract: A process for the production of cationic layer compounds wherein layer compounds corresponding to general formula (I):--[E.sub.e Z.sub.z D.sub.d V.sub.v (OH.sup.-).sub.x ](A.sup.n-).sub.a.qH.sub.2 O-- (I)in whichE is a monovalent cation from the group consisting of alkali metals,e is a number of 0 to 2,Z is a divalent metal cation,z is a number of 0 to 6,D is a trivalent metal cation,d is a number of 0 to 3,V is a tetravalent metal cation,v is a number of 0 to 1,(A.sup.n-) is an acid anion having the charge n- where n is an integer of 1 to 3,q is a number of 1 to 10,with the proviso that x>a and e+2z+3d+4v=x+na, are subjected to alkali-induced ripening in aqueous medium wherein the alkali metal hydroxide content of said aqueous medium is adjusted to a value in the 1- to 6-molar range, the crystallization temperature is adjusted to a value in the range from 60.degree. C. to 100.degree. C., and the crystallization time is adjusted to a value in the range from 2.5 to 50 hours.

Abstract: A hot alkaline liquid soluble or dispersable composition made from a first polymer of an ethylene-acrylic acid copolymer having an acrylic acid portion, an ethylene-methacrylic acid copolymer having a methacrylic acid portion, or a mixture thereof, where the acrylic acid portion and the methacrylic acid portion each, independently, comprise from 10 to 30 wt. % of the total copolymer weight and also including an Ionomer-type copolymer having an acrylic acid portion, a methacrylic acid portion, or a combination thereof, comprising from 10 to 30 wt. % of the total Ionomer copolymer weight. Methods of making articles from such compositions. Methods of disposal of such compositions in hot liquid and alkaline conditions.

Abstract: A polyamide resin composition comprising a copolyamide and silicate layers originating from a swellable fluoromica, dispersed in said copolyamide on a molecular level, wherein an average thickness and an average aspect ratio (length/thickness) of the silicate layers are within specific ranges. Also disclosed is a process for preparing the polyamide resin composition.

Abstract: A flexible self-supporting fire barrier material comprising about 0.5 to about 25 weight % of a structural phase and greater than or equal to about 75 weight % to about 99.5 of inorganic heat absorbing compounds dispersed throughout the structural phase, based on a total weight % of the fire barrier material; the structural phase comprising 0.5 to about 10 weight % binder and 0.01 to about 15 weight % fibers, based on the total weight % of the fire barrier material; the inorganic heat absorbing compounds comprising an intumescent compound and an endothermic compound; the material having a density of at least about 0.5 g/cc.

Abstract: A process for the preparation of a fire-retardant material which comprises a particulate inorganic filler (other than a tin compound) coated with a layer of divalent metal hydroxystannate or a divalent metal stannate, which process comprises the steps of: (i) forming a slurry of the particulate inorganic filler in an aqueous solution of an alkali hydroxystannate, also containing a divalent metal oxide dissolved therein; (ii) reacting the slurry from step (i) with a hydrolysing agent, or a water-soluble source of a divalent metal, to form a layer of a divalent metal hydroxystannate on the surface of the filler, and (iii) optionally, heating the filler coat with hydroxystannate in step (ii) in order to convert it to the corresponding divalent metal stannate.