摘要:
Magnetic recording media consist of a nonmagnetic substrate and at least one magnetizable layer which is firmly applied thereon is based on a magnetic material dispersed in at least one polyureaurethane and a polyurethaneurea (meth)acrylate, the polyurethaneurea (meth)acrylate being obtained by reacting a polyacrylate with a mixture of di- and polyisocyanates and converting the remaining NCO groups into substituted urea groups with aminoalkyltrialkoxysilanes.
摘要:
Polymeric materials (I) are obtainable by reacting1. a polymer II comprisinga) from 80 to almost 100 mol % of a C.sub.1 -C.sub.25 -alkyl ester of an .alpha.,.beta.-unsaturated carboxylic acid,b) from 0 to 20 mol % of a further monomer,c) tetrahydrofuran hydroperoxide as polymerization initiator and, if required,d) a further polymerization initiator and/or regulator by means of which the majority of the polymer chains of the polymer II are terminated at one of their ends by a hydroxyl group,2. with a polyfunctional isocyanate III to give a reaction product IV, the amount of isocyanate groups being from 1.2 to 3.0 mol per mol of hydroxyl groups of II, and3. reacting IV with ammonia or with a compound V which has an amino function reactive toward isocyanates.The polymeric materials can be used as dispersing resins for pigment-containing coatings, in particular for the production of magnetic recording materials.
摘要:
Magnetic recording media consist of a nonmagnetic substrate and at least one magnetizable layer bonded thereon and based on a magnetic material dispersed in at least one polyurethane and one polyurethaneurea (meth)acrylate, the polyurethaneurea (meth)acrylate being obtained by reacting a hydroxyl-containing poly(meth)acrylate with a mixture of di- and polyisocyanates and converting the remaining NCO groups with ammonia or primary or secondary amines into urea groups.
摘要:
Preparation of materials (I) having an average molecular weight from 4000 to 30,000, obtainable by reacting1) a polyurethane (II) comprisinga) 1 mol of a diol (III) having an average molecular weight of from 400 to 4000,b) from 0.3 to 9 mol of an aliphatic or cycloaliphatic diol (IV) of 2 to 18 carbon atoms,c) from 0.3 to 9 mol of an aromatic diol (V) of 8 to 30 carbon atoms,d) from 0.01 to 1 mol of a trihydric alcohol (VI) of 3 to 18 carbon atoms,e) from 0.001 to 1 mol of a polyhydric alcohol (VII) of 3 to 14 carbon atoms which contains a tertiary amino group andf) an amount of a diisocyanate (VIII) of 6 to 30 carbon atoms such that the molar ratio of the isocyanate groups to the total number of hydroxyl groups in (III) to (VII) is from 1.05:1 to 1.4:1with2) a compound (IX) which contains one or more hydroxyl groups and one or more amino groups reactive toward isocyanate groups, the amount of (IX) being such that the number of reactive amino groups corresponds to the number of isocyanate groups in the polyurethane (II).The materials may be used as crosslinkable binder components for pigment-containing coatings, in particular for the production of magnetic recording materials.
摘要:
A polymeric material I is obtainable by reacting 1) a polymer II of a) from 80 to almost 100 mol % of a C.sub.1 -C.sub.25 -alkyl ester of an .alpha.,.beta.-unsaturated carboxylic acid, b) from 0 to 20 mol % of one or more further monomers and c) an initiator and/or regulator by means of which the majority of the polymer chains of the polymer II are terminated at one of their ends by a hydroxyl group, 2) with a polyfunctional nonaromatic isocyanate III to give a reaction product IV, the amount of isocyanate groups being from 1.2 to 3.9 mol per mole of the hydroxyl groups in II, 3) reacting IV with a) a compound V, containing groups reactive toward isocyanates, to give a reaction product VI, the amount of reactive groups being from 2 to 7 mol per mole of the free isocyanate groups still present in IV, and reacting VI with a compound VII to give the polymer I, which reacts with the reactive groups which are still free in VI and by means of which acidic groups are introduced into VI, or b) a compound VIII which contains groups reactive toward isocyanates and by means of which the acidic groups are introduced into IV, to give the polymer I. The polymeric materials can be used as dispersing resin for pigment-containing coatings, in particular for the production of magnetic recording materials.
摘要:
In magnetic recording media consisting of a nonmagnetic substrate and one or more magnetizable layers bonded thereon and based on a polyurethane binder, the binder consists of not less than 50% by weight of an isocyanate-free, branched polyurethane which is soluble in tetrahydrofuran and has sulfonate groups along the polyurethane branches and OH-containing urea groups at the chain ends and a molecular weight of from 4,000 to 30,000.
摘要:
Flexible magnetic recording media essentially consist of a web-like nonmagnetic substrate, a magnetic layer applied to one main side of the web-like substrate and a backing coating formed on the opposite main side of the substrate from a polymeric binder and nonmagnetizable fillers and supporting pigments.
摘要:
Magnetic recording media consist of a nonmagnetic substrate and one or more magnetizable layers bonded thereon and based on a polyurethane binder, the binder consisting of not less than 50% by weight of a branched polyurethane elastomer having sulfonate groups and possessing urea groups at the chain ends.
摘要:
In magnetic recording media consisting of a nonmagnetic substrate and at least one magnetizable layer firmly applied thereon and based on magnetic material dispersed in a binder mixture which contains at least one hydroxyl-containing, preferably low molecular weight polyureaurethane and one polyurethaneurea (meth)acrylate, the polyurethaneurea (meth)acrylate is obtained by reacting a poly(meth)acrylate having up to 2 terminal OH groups per mol and a molecular weight of from 200 to 50,000 with a mixture of aliphatic polyisocyanates having an average functionality of from 3.0 to 6.0 NCO groups per mol, consisting offrom 0.1 to 10% by weight of a diisocyanate, from 30 to 80% by weight of a triisocyanate and from 20 to 60% by weight of an isocyanate having a functionality of from 4 to 10, with the proviso that from 1.2 to 3.0 NCO groups react per OH group and the remaining NCO groups are converted into substituted terminal urea groups with a polyfunctional amine or with a mixture of different polyfunctional amines.
摘要:
The present invention relates to the use of homopolymers or copolymers of (meth)acrylic acid or copolymers of C3-C40-monoolefins with ethylenically unsaturated C4-C6-dicarboxylic anhydrides as additives in ceramic masses, in particular in brick earth and clay for producing building ceramics such as bricks and roofing tiles, and also ceramic masses comprising these additives.