Hoechst Aktiengesellschaft

Matthias Kroggel

Dieter Mohr

Waltraud Mueller-Hess

Karl-Josef Rauterkus

Joachim Gersdorf

Karl J Rauterkus

Matthias Gutweiler

Hans-Dieter Hermann

Werner Kramer

Stefan Mullner

Hans-Ullrich Huth

Hermann Schindler

Detlev Seip

Bettina Gerharz

Hans-Ulrich Huth

Process for preparing dispersions stabilized with protective colloid using sulfonato-containing polyvinyl acetals as the protective colloid in the preparation of the dispersions, if desired in combination with additional emulsifiers or additional protective colloids. The dispersions exhibit a pH-dependent viscosity and are suitable, for example, for coating and bonding substrates and as rheology modifiers and binders and for use in solid paints.

Process for preparing dispersions stabilized with protective colloid

Graft polyvinyl acetals having acetal groups from etherified .omega.-hydroxy(poly)alkoxyalkanals, processes for their preparation and their use Polymeric acetals of polyvinyl alcohols grafted onto polyalkylene oxide graft bases or onto polyurethane graft bases, which contain acetal groups from etherified .omega.-hydroxy(poly)alkoxyalkanals of the formula (I), and processes for their preparation by acetalization of corresponding graft polyvinyl alcohols are described. The polymeric acetals according to the invention are polymers which are plasticized internally and in general obtainable in solid form and which can be processed to films, shaped articles or coatings by thermoplastic methods without external plasticizers. Mixed acetals with other aldehydes can also be prepared and allow wide variants in the properties, inter alia the solubilities in water or in organic solvents. The polymeric acetals according to the invention can be processed or used in bulk, for example from the melt, or as organic or aqueous solutions or as aqueous dispersions.

Graft polyvinyl acetals having acetal groups from etherified

Preparation of polyvinyl acetals which can form emulsifier- and surfactant-free aqueous dispersions and redispersible dry powders and contain copolymeric polyvinyl acetals with, in amounts sufficient to form a dispersion, comonomer units carrying sulfo salt groups which are derived from copolymeric polyvinyl alcohol (PVALs) which contained comonomer units carrying sulfonate groups in the salt form. The preparation is carried out by acetalization of the starting polyvinyl alcohols to be used with aldehydes or aldehyde acetals under acid-catalyzed acetalization conditions in an aqueous medium, emulsifier-free stable aqueous polyvinyl acetal dispersions being obtained, from which dry redispersible polyvinyl acetal powders can be obtained by spray drying or freeze drying. The polyvinyl acetals according to the invention can be plasticized by mixing in plasticizers both in their aqueous dispersion form and in the dry powder form. The polyvinyl acetals according to the invention can be employed, both in the aqueous dispersion form and in the dry powder form, in numerous fields of use where polyvinyl acetals of the type known to date are already usually used. Moreover, because of the advantageous spectrum of properties of polyvinyl acetals according to the invention, numerous new fields of use are accessible.

Polyvinyl acetals which can form emulsifier-free aqueous dispersions and

Polymeric and oligomeric bile acids are described which can be prepared by polymerization of monomeric bile acids of the formula I

Polymers and oligomers of bile acid derivatives, process for their

Preparation of soluble polyvinyl acetals having a low degree of crosslinking, which show improved melt viscosity characteristics, by acetalization of soluble polyvinyl alcohols having a low degree of crosslinking, which have been obtained by hydrolysis or alcoholysis of soluble copolymers having a low degree of crosslinking of vinyl esters and monomers having multiple ethylenic unsaturations, for example, glyoxal bisacrylamide. As against comparable non-crosslinked, soluble polyvinyl acetals, polyvinyl acetals having a low degree of crosslinking according to the present invention show increased intrinsic viscosities and surprisingly exhibit advantageous properties in thermoplastic forming, in particular when extruded in a plastified form. The polyvinyl acetals having a low degree of crosslinking furthermore have improved mechanical properties in comparison with non-crosslinked polyvinyl acetals and, in the form of plastified films, are particularly advantageously employed in the production of composite glass.

Polyvinyl acetals having improved melt viscosity characteristics,

A photosensitive mixture is disclosed that contains a photocurable compound, for example, a diazonium salt polycondensation product, or a photocurable combination of compounds, for example, a photopolymerizable mixture, and a polymeric binder, which binder is a graft copolymer with a polyurethane graft backbone onto which chains containing vinyl alcohol units and vinyl acetal units derived from hydroxyaldehydes are grafted. The mixture is suitable for use in the production of printing plates and photoresists, can be developed with purely aqueous solutions, and gives printing plates distinguished by high resistance to mechanical and chemical attacks.

Photosensitive mixture containing photocurable compound and polyurethane

A photopolymerizable mixture is disclosed which contains:

Photopolymerizable mixture and recording material containing

Acetals of polyvinyl alcohol (PVAL) which contain vinyl oxoacetal units of the formula I which are derived from aldehydes containing keto groups (oxoalkanals) and can be crosslinked with hydrazine or polyfunctional hydrazine derivatives or polyfunctional carboxylic acid hydrazides via their keto groups to give high molecular weight products having a variable spectrum of properties are described. Mixed acetals with aldehydes which contain no keto groups can also be prepared and can be crosslinked via the keto groups of the vinyl oxoacetal units. Products which are obtained from PVALs and oxoalkanals or low molecular weight acetals of the oxoalkanals and contain vinyl oxoacetal units are preferably prepared in aqueous or organic media under acid catalysis. For the use of polyvinyl oxoacetals according to the invention, preferably as polymeric binders and coating agents, these can preferably be employed in dissolved or dispersed form, with addition of the abovementioned crosslinking agents, for a number of fields of use, it being possible for the crosslinking to be carried out during or after drying of these solutions or dispersions to form sparingly soluble and swellable or insoluble and non-swellable polymeric modifications having surprisingly advantageous properties.

Oxoacetals of polyvinyl alcohols, processes for their preparation and

Disclosed is a graft polymer comprising a polyurethane graft backbone and grafted-on chains comprising vinyl alcohol units and units with lateral styrylpyridinium or styrylquinolinium groups, and also a photocurable mixture comprising the graft polymer and a photosensitive compound, such as a photosensitizer of a negative-working diazo compound. The mixture is suited for the production of printing plates, in particular planographic printing plates, and photoresists. Printing plates prepared from the mixture are distinguished by high photospeed, good developability with aqueous solutions and long print runs.

Graft polymer with unsaturated lateral chains, photosensitive mixture

A photocurable elastomeric mixture is described which comprises a compound which contains at least one terminal ethylenically unsaturated group and is polymerizable by free radical polymerization, a photopolymerization initiator and, as binder, a graft polymer which is soluble or dispersible in water or an aqueous solution, the graft base of which is a polymer of diol components and diisocyanate components having at least 2 urethane groups in the molecule, onto which polymer carboxylic acid vinyl ester units having 3 to 20 carbon atoms, or their saponification products, are grafted. The mixture is suitable for the production of relief printing plates, in particular flexographic printing plates, and can be developed with water or aqueous solutions.

Photocurable elastomeric mixture and recording material, obtained

Graft polymers in which carboxylic acid vinyl esters and if appropriate other ethylenically unsaturated monomers are grafted polymerically onto polyurethane graft bases by means of grafting polymerization initiated by free radicals, and hydrolysis products of the graft polymers can be obtained by grafting carboxylic acid vinyl esters with 3 to 20 carbon atoms and if appropriate other ethylenically unsaturated polymerizable monomers, which are copolymerizable if appropriate, in amounts of 10 to 99% by weight, based on the graft polymer, onto a polyurethane graft base by grafting polymerization initiated by free radicals, and if appropriate subsequently partly or completely hydrolyzing the vinyl ester units and if appropriate other hydrolyzable monomer units in the grafted-on polymer radicals of the graft polymers by hydrolysis and/or alcoholysis. Preferred vinyl esters to be grafted on are vinyl acetate and/or vinyl propionate and if appropriate vinyl versatate. The grafting polymerization is carried out in solution or in bulk and can also be carried out in emulsion or suspension.

Graft polymers with a polyurethane graft base, processes for their

A photocurable mixture is disclosed that contains a diazonium salt polycondensation product or an organic azido compound as the photosensitive compound and a high-molecular weight polymer as the binder, the polymer being a graft copolymer with a polyurethane as the graft backbone, onto which chains containing vinyl alcohol units are grafted. The mixture is suitable for use in the production of printing plates and photoresists, which can be developed with aqueous solutions. It yields printing plates having a good ink acceptance and long shelf life that produce large print runs.

Photocurable mixture and material containing diazonium salt

The invention describes a graft polymer based on a graft base which contains a polymer comprising diol components and diisocyanate components which has at least two urethane groups in the molecule, onto which graft base have been grafted polymer chains comprising units of vinyl esters of carboxylic acids, having 3 to 20 carbon atoms, and/or hydrolysis products thereof, and optionally units of other ethylenically unsaturated monomers or hydrolysis products thereof and which are additionally esterified in the melt in homogeneous phase with an acylating reagent, in particular with carboxylic anhydrides. The product is insoluble in water, but soluble in aqueous alcohol solution and can be used as a binder in light-curable mixtures for the preparation of relief printing plates. Also described is a process for the preparation of the graft polymers mentioned above, in which on catalyst is used and consequently a colorless product results. The product is obtained from the homogeneous phase.

Carboxylic esters of hydroxyl-containing graft polymers and process for

Disclosed is a photocurable mixture which is suited for the production of printing plates, in particular planographic printing plates, and photoresists. The mixture comprises a graft polymer comprised of a polyurethane as the graft backbone and grafted-on chains containing vinyl alcohol units and units with lateral, polymerizable or crosslinkable double bonds, and a photosensitive compound, such as a photoinitiator or a negative-working diazo compound. The printing plates prepared from the mixture are distinguished by high photospeed, good developability with aqueous solutions and long print runs.

An electrophotographic copying material is disclosed containing, in the photoconductive film, a high-molecular-weight polymer binder which is a graft polymer having a polyurethane as grafting base and grafted-on chains which contain vinyl alcohol units. The material is suitable, in particular, for the production of printing plates and printed circuits which are highly photosensitive and laminatable even at fairly large film thickness. The films can be treated with mild and toxicologically safe stripper solutions.

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Kelkheim, Germany

Matthias Kroggel