Abstract: Modified stable polyisocyanates are described having at least one isocyanate function modified by a group having cross-linking functionality.

Abstract: A process is described for drying melamine wet cakes, comprising the steps of: a) providing a turbo-dryer (T) comprising a cylindrical tubular body (1) having a heating jacket (4), inlets and outlets (5,6) and a bladed rotor (7) rotatably supported therein; b) feeding a continuous flow of a melamine wet cake into the turbo-dryer (T), the internal wall (9) of which is maintained at a temperature of at least 220° C.; c) feeding a continuous flow of a gas selected from air or nitrogen into the turbo- dryer (T); d) subjecting the flow of melamine wet cake to the mechanical action of the bladed rotor (7) rotating at a speed of at least 200 rpm, with consequent centrifugation of the wet cake against the heated wall (9), thus causing the instantaneous evaporation of the water contained into the cake, and transport of the latter towards the outlet (6); e) continuously discharging, after an average residence time of less than 1 minute, a flow of melamine crystals having a humidity content of less than 0.1%.

Abstract: This invention relates to storage-stable, liquid, partially trimerized and allophanized polyisocyanates having an NCO group content of 15 to 41% by weight, and comprising 5 to 85% by weight of toluene diisocyanate, 5 to 85% by weight of a polyisocyanate of the diphenyl-methane series and an organic compound or mixture thereof. The present invention also relates to a process for the preparation of the storage-stable, liquid, partially trimerized and allophanized polyisocyanates; to storage-stable, liquid urethane prepolymers of these partially trimerized and allophanized polyisocyanates; and to a process for the production of these storage-stable, liquid, urethane prepolymers.

Abstract: The use of a compound comprising a nitrogenous heterocyclic group with five cyclic members including, at least two nitrogen atoms, one of the nitrogen atoms bearing a hydrogen atom to promote the opening/closing reaction of uretidione cycles in the presence of a nucleophile compound provided that, when the nitrogenous heterocyclic group is imidazole, the opening/closing reaction is not the closing reaction of the uretidione cycle in the presence of a quaternary ammonium salt.

Abstract: A composition comprising a self-emulsifiable or self-dispersible aqueous solution or dispersion of at least one urea linkage-containing alkoxypolyoxyalkylene fluorocarbamate prepared by contacting (a) at least one polyisocyanate which contains at least three isocyanate groups per molecule, (b) at least one fluorochemical reagent of the formula F(CF2)aCH2CH2OH, wherein a is 4, 6, or 8, or mixtures thereof, provided that a is a maximum of 50% of 8, and (c) at least one hydrophilic, water-solvatable reagent which contains per molecule a single functional group which has at least one reactive Zerewitinoff hydrogen atom, and thereafter with (d) water, the equivalent weight of the polyisocyanate and the reagents (b) and (c) being such that the reagents react with 55% to 95% of the isocyanate groups, and water reacts with all of the remaining isocyanate groups, the composition imparting durable hydrophilicity and stain release properties to a substrate treated therewith is disclosed.

Abstract: A compound of formula wherein the substituents have various meanings, useful as a pharmaceutical.

Abstract: Described are compounds useful for trimerising chemical entities, methods of trimerising chemical entities, and trimerised entities. In one aspect, the entities are peptides.

Abstract: Isocyanurate compounds or resins have the structure (I) in which Y is an hydroxyl group —OH or a maleimide group Formula (II) provided that at least one maleimide group is present, and Q is any divalent organic moiety, aliphatic or aromatic.

Abstract: High-functionality polyisocyanates are prepared by a process which comprises (i) preparation of an addition product (A) which contains one group which is reactive toward isocyanate and at least two isocyanate groups by reacting (a) a diisocyanate or polyisocyanate I with (b1) compounds having at least three groups which are reactive toward isocyanate or (b2) compounds containing two groups which are reactive toward isocyanate or mixtures of (b1) and (b2), where at least one of the components (a) or (b) has functional groups having differing reactivities toward the functional groups of the other component and the reaction ratio is selected so that the addition product (A) contains an average of one group which is reactive toward isocyanate, (ii) if desired, intermolecular addition reaction of the addition product (A) to form a polyaddition product (P) containing an average of one group which is reactive toward isocyanate and an average of more than two isocyanate groups, and (iii) reaction of the addition

Abstract: The present invention concerns a process for producing low-viscosity polyisocyanates or secondary products thereof, which carry activated, radiation-curable double bonds and can optionally also cure thermally, and low-viscosity polyisocyanate mixtures or secondary products thereof and their use in coating compounds.

Abstract: A method of dimerizing isocyanates using sulphonamide anions as a dimerization catalyst for the isocyanates and also to a process for preparing oligomeric isocyanates using such catalysts.

Abstract: A method is described for preparing a tricondensate polyfunctional isocyanate composition, preferably having at least an isocyanurate and/or biuret group, which includes adding to a tricondensate polyfunctional isocyanate, or a mixture of different tricondensate polyfunctional isocyantes, obtained by (cyclo)condensation, in particular (cyclo)trimerization of one or several identical or different isocyanate monomers and optionally of another monomer, an allophanate of one or several identical or different isocyanates, or a mixture of different allophanates. The isocyanates or isocyanate monomer mixtures used for preparing the polyfunctional isocyanate(s) may be identical to or different from the isocyanate(s) or isocyanate mixture used for preparing the allophanate(s).

Abstract: The present invention is directed to nitrile-oxide precursor compounds, and their preparation and use as an irreversible cross-linking agent in polymers having appropriate functionality, i.e., alkenes, alkynes nitriles, and isocyanates. The present invention is also directed to the use of nitrile oxide compound in filled or unfilled applications such as pressure sensitive adhesives, reactive hot melts, polyurethane dispersions, thermosetting adhesives, thermoplastic adhesives or coatings.

Abstract: A polyisocyanate composition comprising an allophanate group, which is obtained from an aliphatic diisocyanate(s), wherein in a state substantially free of a solvent and the aliphatic diisocyanate(s), (i) the content of components having a molecular weight of 700 or less is 20-60 weight %, (ii) the ratio of weight average molecular weight to number average molecular weight is 1.20-5.00, (iii) the ratio of viscosity (unit: mPa·s) of the polyisocyanate composition at 25° C. to the number average number of functional groups of isocyanate groups is represented by the following expression: viscosity(mPa·s)/number average number of functional groups?240.

Abstract: The invention concerns a polyisocyanate composition having high functionality, obtained by polycondensation of diisocyanate or triisocyanate monomers, comprising: (a) 0.5 to 30 wt % of compounds bearing a single uretidinedione function; (b) 0.5 to 45 wt. % of compounds bearing a single isocyanurate function; (c) at least 40 wt. % of a mixture of polyisocyanate compounds having a molecular weight not less than three times the average molecular weight of the isocyanate monomers having the smallest molecular weight and bearing at least two isocyanate functions, said mixture having a ratio of carbonyl functions belonging to a uretidinedione cycle/carbonyl functions belonging to an isocyanate cycle+carbonyl functions belonging to a uretidinedione cycle not less than 4%; (d) 0 to 25 wt. % of compounds bearing at least an isocyanate function other than (a), (b) and (c); and (e) 0 to 10% of impurities.

Abstract: A process for the preparation of 3-cyclic-ether-substituted cephalosporins of formula I wherein the group CO2R1 is a carboxylic acid or a carboxylate salt and R2 has the formula: wherein A1 and A2 have the meanings given in the specification by reacting compound of formula II: wherein R2 is as defined above and R3 is para-nitrobenzyl or allyl with a compound R2 L wherein R2 is as defined above; and L is di-(C1-6 alkyl)phosphorothioate in the presence of a solvent and a base.

Abstract: A method is described of preparing (poly)isocyanurate polyisocyanates by catalytic cyclotrimerization of isocyanates. A catalytic system is used which includes a cyclotrimerization catalyst based on a quatemary ammonium salt and imidazole as a cocatalyst.

Abstract: The present invention relates to the use of sulphonamide salts as catalysts for oligomerizing isocyanates and also to a process for NCO oligomerization using the catalysts of the invention.

Abstract: A process for the production of compounds which contain at least one urea group and at least one silyl group. The process involves reacting a compound containing at least one amino group and a carbamate compound. The compounds produced by this process are useful as surface coating compositions, foams and adhesives.

Abstract: A blocked polyisocyanate adduct including 5 to 95% by weight of at least one isocyanate component having at least one NCO group, the isocyanate component selected from the group consisting of aliphatic, cycloaliphatic and aromatic isocyanates, wherein the isocyanate has an average molecular weight of up to 1000 g/mol and an average NCO functionality of 2–4; 5 to 70% by weight of at least one hydrophilicizing component containing at least one group which is reactive toward the at least one NCO group; at least one blocking agent for blocking from 95 to 100% of the NCO groups which do not react with the hydrophilicizing component; and up to 15% by weight of at least one neutralizing agent.

Abstract: The present invention provides a composition of matter having the structure: where Q is a multi-valent organic moiety containing isocyanurate functionality; X is H, —CH2OH, or —CH2OR?; R? is an alkyl or aryl group having from 1 to 12 carbon atoms; and y is at least 2. Also provided is a curable composition containing the composition of matter.

Abstract: A low-viscosity polyisocyanate of reduced color, containing isocyanurate groups is prepared by partially trimerizing an aliphatic and/or cycloaliphatic diisocyanate in the presence of 0.02 to 2% weight, based on the weight of the diisocyanate starting material, of at least one trimerization catalyst containing a quarternary amine component and then removing excess diisocyanate from the reaction medium.

Abstract: The invention relates to a novel process for preparing low-monomer-content trimers based on 2,4- and/or 2,6-diisocyanatotoluene (TDI). A catalytic trimerization is carried out in a mixture of from 20 to 80% by weight of a diisocyanate component containing at least 80% by weight of 2,4- and/or 2,6-diisocyanatotoluene, from 20 to 80% by weight of solvent, and 0–20% by weight of an alcohol component, and also phenolic catalysts containing dialkylamino-methyl groups. In the course of ongoing trimerization, in one or more steps, additional monomeric 2,v4-diisocyanatotoluene is metered in.

Abstract: Polyaddition compounds containing uretdione groups prepared by reacting uretdione polyisocyanates formed from diisocyanates having exclusively secondary- and/or tertiary-attached isocyanate groups with a molar fraction of isocyanurate structures, based on the sum of uretdione groups and isocyanurate groups, of not more than 10%, with compounds reactive towards isocyanates. The polyaddition compounds can be use as a starting component in the preparation of polyurethane plastics, in particular as crosslinkers for heat-crosslinkable powder coating materials. The compounds may be used as starting components in the preparation of moldings and shaped parts, and as starting components in the preparation of coating materials and coatings.

Abstract: The invention concerns a method for catalytic (cyclo)condensation of monomer isocyanates, characterised in that it comprises: a) reacting starting monomer isocyanates with a catalyst comprising a mineral or organic salt of a compound of formula (I), wherein Y? is selected among: a negatively charged oxygen atom, and a carbonaceous radical comprising a negative charge borne by an atom of column VB of the periodic table or by an oxygen atom advantageously by a nitrogen atom and whereof the bond with the silicon of formula (I) is borne by an atom of column VB of the periodic table, advantageously by a nitrogen atom; wherein R1, R2 and R3, identical or different, represent a monovalent hydrocarbon radical having advantageously 1 to 30 carbon atoms, or a precursor of said compound, at a temperature of at least 20° C. and advantageously of at least 40° C. and not more than 200° C., advantageously not more than 150° C.

Abstract: The invention relates to a novel process for preparing low-monomer-content trimers based on 2,4- and 2,6-diisocyanatotoluene (TDI) and to the use thereof in coatings. The trimers are produced from a mixture of from 20 to 80% by weight of diisocyanate component containing at least 80% by weight of 2,4- and/or 2,6-diisocyanatotoluene and from 20 to 80% by weight of solvents and/or diluents and also phenolic catalysts containing dialkylaminomethyl groups.

Abstract: A prepolymer is prepared by reacting a mixture containing (a) at least one multifunctional compound, (b) at least one diisocyanate, and (c) at least one diol. The diol has a weight average molecular weight of at most 6000. The prepolymer, when reacted with an excess of water, forms a hydrogel polymer. The mixture of the prepolymer and water may be reaction molded, and used to form a contact lens.

Abstract: Catalysts and processes for preparing polyisocyanates containing isocyanurate groups, and their use, wherein the catalysts are represented by the following formula (1): [Hl?Xm?Fn?]p·[R(4?q)Si(NR1R2)q]r??(I), wherein n=m+l with 1?m/n>0, and l?0, p>0 and r>0, and the ratio p/r is any value, q=1 or 2, and R, R1, R2 and X are as defined.

Abstract: The solid-phase synthesis of individual 1,3-disubstituted and 1,3,5-trisubstituted-1,3,5-triazine-2,4,6-triones and libraries thereof from a resin is described. Reaction of resin-bound amino acids with isocyanates yields resin-bound ureas, which further react with chlorocarbonyl isocyanate to selectively afford the resin-bound 1,3-disubstituted-1,3,5-triazine-2,4,6-triones. Selective alkylation at the N-5 position of the resin-bound 1,3-disubstituted-1,3,5-triazine-2,4,6-triones produces a trisubstituted triazinetrione. The products are cleaved from their solid support and obtained in good yield and purity.

Abstract: Substituted aryl ether derived compounds represented by general structure (I) are described. X and Y are independent of each other and are represented by hydrogen, halogen, cyano, nitro, (C1-4)alkyl, (C1-4)haloalkyl, or (C1-4)haloalkoxy; Z is oxygen or sulfur, Q is selected form Q1 to Q6; A is oxygen, sulfur, or imino; R1 is hydrogen, (C1-4)alkyl, (C1-4)haloalkyl, or amino and can be independent of each other in a single molecule; R2 and R3 are independent of each other and may be selected from the group consisting of hydrogen, halogen, cyano nitro, (C1-4)alkyl, (C1-4)haloalkyl, (C2-4)alkenyl, (C2-6)haloalkenyl and amino which may be optionally substituted with (C1-4)alkyl or (C1-4)haloalkyl; Ar is substituted or unsubstituted carbocyclic or heterocyclic aromatic ring being at least a five or six membered ring. This ring can be fused with another substituted or unsubstituted five or six membered carbocyclic or heterocyclic ring. When Q is Q5, unsubstituted or substituted phenyl is excluded.

Abstract: The invention relates to polyether-modified, water-dispersible polyisocyanate mixtures, a process for their production and their use as initial component in the production of polyurethane plastics.

Abstract: Low-odor, storage-stable monomer-containing polyisocyanurate is prepared from isophorone diisocyanate by conducting a partial trimerization for 3 minutes to 3 hours in the presence of 0.05-2% by weight of a catalyst, based on the weight of the diisocyanate, the catalyst having the formula [R—NX3]m⊕mY⊖ wherein Y⊖ is a carboxylic acid anion of 4-8 carbons, R is a &bgr;-hydroxyalkyl group of 2-6 carbons, X is an alkylene group of 2-3 carbons and m is a number from 1.0 to 2.0. The three radicals X form a ring with the quaternary nitrogen by way of a common nitrogen atom, which may be partly &bgr;-hydroxyalkylated, said ring optionally having an OH group positioned &agr;, &bgr; or &ggr; to the nitrogen. The reaction proceeds at a temperature of 0-160° C.

Abstract: The invention concerns a (cyclo)trimerisation method for isocyanates having at least two isocyanate functions, characterised in that it comprises: a) reacting initial isocyanate monomers having at least two isocyanate functions, optionally in the presence of other monomers reactive with the isocyanate monomers having at least two isocyanate functions at a temperature of at least 20° C., advantageously at least 50° C., and lower than 200° C., advantageously lower than 150° C., in the presence of a compound comprising at least one rare earth alcoholate function; b) stopping the reaction by inactivating the catalyst or its derivative forms in the reaction medium at a transformation rate of at least 2.5% and at most 90% of the initial isocyanate functions; and optionally c) distilling the reaction medium to eliminate the unreacted monomers.

Abstract: Compounds and compositions for the delivery of active agents are provided. Methods of administration and preparation are provided as well.

Abstract: This invention relates to the use as catalyst for the cyclotrimerization reaction of isocyanates of a hydrogencarbonate of a cation which either as it is or in the form complexed with a complexing agent has an average molecular or ionic radius of more than 1 Å, preferably greater than 1.5 Å, and which is at least partially soluble in the reaction medium. The invention also relates to a method of preparing (poly)isocyanurate polyisocyanates by catalytic cyclotrimerization of isocyanates, in which a catalytic system is used which comprises a cyclotrimerization catalyst based on a quaternary ammonium salt as catalyst and imidazole as cocatalyst.

Abstract: A low-viscosity polyisocyanate of reduced color, containing isocyanurate groups is prepared by partially trimerizing an aliphatic and/or cycloaliphatic diisocyanate in the presence of 0.02 to 2% by weight, based on the weight of the diisocyanate starting material, of at least one trimerization catalyst containing a quarternary amine component and then removing excess diisocyanate from the reaction medium.

Abstract: Novel 1-aryl-4-thiotriazines I where the variables have the following meanings: R1=H, NH2, C1-C4-alkyl, C1-C4-haloalkyl; R2=H, NH2, C1-C4-alkyl, C1-C4-haloalkyl; R3=H, halogen; R4=CN, halogen; Y=nitrogen, the methine group or, together with R5, a bridge >C—O—C(R6)═N—; R5=one of the meanings given in the description; R6=H, halogen, substituted or unsubstituted C1-C6-alkyl, C3-C6-alkenyl, C3-C6-alkynyl, C1-C6-alkoxy, C3-C6-alkenyloxy, C3-C6-alkynyloxy, C3-C6-cycloalkyl or C3-C6-cycloalkoxy; their salts and enol ethers, the preparation of the novel compounds I and their use as herbicides.

Abstract: GnRH receptor antagonists are disclosed which have utility in the treatment of a variety of sex-hormone related conditions in both men and women.

Abstract: The invention relates to a method of preparing an aliphatic polyisocyanate by conversion of an aliphatic diisocyanate to a polyisocyanates in the presence of a catalyst, wherein the catalyst contains a saline compound having 5 to 97.1 wt. % of a 1,2,3- and/or a 1,2,4-triazolate (calculated as C2N3, molecular weight 66) in the anion, the isocyanates thus prepared and the polyurethane paints and coatings containing them.

Abstract: Compounds of general formula (1) are described wherein: Ar is an optionally substituted aromatic group; R2 is a hydrogen or halogen atom or a group —X1—R2a where X1 is a direct bond or a linker atom or group, and R2a is an optionally substituted straight or branched chain alkyl, alkenyl or alkynyl group; R3 is an optionally substituted heterocycloalkyl group; and the salts, solvates, hydrates and N-oxides thereof. The compounds are selective protein tyrosine kinase inhibitors, particularly the kinases ZAP-70 and syk and are of use in the prophylaxis and treatment of immune or allergic diseases and diseases involving inappropriate platelet activation.

Abstract: This invention relates to storage-stable, liquid, partially trimerized polyisocyanates having an NCO group content of 24 to 40% by weight, and comprising 20 to 88% by weight of toluene diisocyanate and 12 to 80% by weight of a polyisocyanate of the diphenylmethane series. The present invention also relates to a process for the preparation of the storage-stable, liquid, partially trimerized polyisocyanates; to storage-stable, liquid urethane prepolymers of these partially trimerized polyisocyanates; and to a process for the production of these storage-stable, liquid, urethane prepolymers.

Abstract: The present invention relates to blocked polyisocyanates which are the reaction product of polyisocyanate resins prepared from HDI and containing iminooxadiazinedione groups in an amount of at least 20 mol %, based on the total moles of iminooxadiazinedione and isocyanurate groups, with alcohols of formula (I) ROH  (I), wherein R represents aliphatic, straight chain or branched, optionally cyclic, optionally substituted (O—R1, NR12), C1-C6 radicals, preferably C1-C4 radicals, and R1 has the same meaning as R. The present invention also relates to a process for the preparation of blocked polyisocyanates and to their use for the preparation of polyurethane plastics and coatings, preferably for coating substrates.

Abstract: Pigment dispersants prepared by reacting an isocyanate oligomer having an average functionality of at least three with a polyester or polyacrylate, a poly(ethylene glycol)alkyl ether, and a diamine having a primary amine and a tertiary amine have excellent stabilizing properties and offer a wide formulation latitude with a variety of solvent systems, including polar solvents and water, and are particularly useful as pigment dispersants for paints and coating applications.

Abstract: The invention provides polyisocyanates containing isocyanate groups from 1,4-diisocyanato-2,2,6-trimethylcyclohexane, having a trimer fraction of more than 80% by weight and an NCO content of at least 19.3%.

Abstract: The invention concerns a compound of formula (I) in which m is to 0 or 1 Iso is the (poly)isocyanate radical (after elimination of an isocyanate function); R10 is selected among: a negative charge; a hydrocarbon-based radical (i.e. a residue containing hydrogen and carbon atoms) having a carbon as it binding point [i.e. the atom carrying the open bond]; R11 is selected among a negative charge. The invention is applicable to organic synthesis.

Abstract: The present invention provides a process, which includes: partially trimerizing isophorone diisocyanate in the presence of a catalyst having the formula: [R—NX3]⊕Y⊖ wherein R and X are butyl groups and Y− is CH3COO−; or wherein R is a benzyl group, Y− is a carboxylate anion having from 4 to 8 carbon atoms and each X is an alkylene group having from 2 to 3 carbon atoms, wherein the three alkylene groups share a common carbon atom and, together with the N atom in the formula, form a tricyclic structure, and wherein at least one alkyene group has at least one OH group in an &agr; or &bgr; &ggr; position relative to the N atom, to obtain a monomer-containing polyisocyanurate mixture. The present invention also provides a monomer-containing polyisocyanurate mixture made from the above process.

Abstract: The present invention provides a solventless, continuous process, which includes: in at least one extruder, intensive compounder, intensive mixer or static mixer, mixing and heating a reaction mixture including the following (A), (B), and one or both of (C) and (D): (A) at least one aliphatic, (cyclo)aliphatic and/or cycloaliphatic C3-C50 diisocyanate compound; (B) at least one aliphatic, (cyclo)aliphatic and/or cycloaliphatic C3-C50 polyisocyanate compound containing one or more isocyanurate groups; (C) 1,2,4-triazole; (D) one or more pyrazole having the formula: where R1, R2 and R3 simultaneously or independently of one another are hydrogen or alkyl, alkenyl, aralkyl, aryl or N-substituted carbamoyl groups, halogen or —C(═O)—O—R4, where R4 is a C1-C12 alkyl group; to obtain a product mixture including at least one (semi)crystalline, blocked C3-C50 isocyanate compound and at least one amorphous, blocked C3-C50 isocyanate compound.

Abstract: The present invention relates to water dispersible polyisocyanate mixtures prepared from aliphatic, cycloaliphatic, araliphatic and/or aromatic diisocyanates and having a) an average isocyanate functionality of at least 2.0, b) a content of 5.0 to 25.0 wt. %, based on resin solids, of isocyanate groups (calculated as NCO; molecular weight=42) and c) a content of 2 to 50 wt. %, based on resin solids, of ethylene oxide units calculated as C2H2O; molecular weight 44) incorporated within polyether chains containing an average of 5 to 35 ethylene oxide units, wherein at least 60 mole % of the polyether chains are connected via allophanate groups to two polyisocyanate molecules which are each prepared from at least two diisocyanate molecules. The present invention also relates to a process for the preparation of these water dispersible polyisocyanate.

Abstract: The present invention relates to polyisocyanate mixtures prepared from aliphatic and/or cycloaliphatic diisocyanates and having a) an average isocyanate functionality of at least 2.0, b) a content of isocyanate groups (calculated as NCO; molecular weight=42) of 4.0 to 28.0 wt. % and c) a content of alkoxy groups having up to 36 carbon atoms of 2.0 to 37.5 wt. %, wherein the alkoxy groups are constituents of allophanate groups or optionally urethane groups, provided that >50 mol % of the alkoxy groups are a constituent of allophanate groups that are connected to at least two polyisocyanate molecules which are each prepared from at least two diisocyanates. The present invention also relates to a process for preparing these polyisocyanate mixtures and to coating compositions, which are highly diluted or dilutable with non-polar solvents and contain these polyisocyanate mixtures and lacquer binders or binder components optionally containing isocyanate-reactive groups.

Abstract: The invention describes fluorochemical triazine compounds, compositions containing the fluorochemical triazine compounds, the process for preparing the fluorochemical compounds and compositions, substrates treated with the fluorochemical compounds, melt extrusion of fibers and films containing the fluorochemical compounds and compositions, and coating, polish and marine antifouling compositions to provide oil and water repellency to substrates.

Abstract: Alignment in X-ray lithography is generally effected in such a manner that the surface of a target mark for alignment formed on a wafer is illuminated with light for alignment through an X-ray mask, and the position of the wafer is detected from the reflected light. On the basis of the finding that the reflected light from the mask, particularly from an absorber formed thereon, greatly degrades the precision and reliability in measurement, the present invention provides a pattern transfer mask provided with a thin film which lowers the reflection factor of the mask the thin film having a thickness set a .lambda./4n (.lambda.:the wavelength of the light for alignment; n: an integer) or an odd-number multiple thereof. Thus, it is advantageously possible to overcome the above-described lowering of precision and reliablity.