Abstract: A method of making a polymeric compound, comprising discrete particles responsive to an external stimulus, that is resistant to aggregation in high-shear fields, which includes the addition of a polymerization initiator to a reaction mixture comprising a monomer corresponding to the polymeric compound, wherein the method comprises the portion-wise addition of aliquots of a cross-linking agent to the reaction mixture, wherein an aliquot of the cross-linking agent is added to the reaction mixture both before the addition of the polymerization initiator and after the polymerization has progressed substantially to completion. The polymer particles are largely immune to the effects of transient shear rates at least as high as 106 s?1, whilst maintaining their thermal responsiveness and being present at moderate concentration. The structural and chemical modifications brought by the delayed portion-wise addition of the cross-linking agent allow an improvement in stability in a high-shear field.

Abstract: A stimulus-responsive polymer particulate composition, comprising a first monomer, such as an aqueous microgel derived, for example, from N-isopropylacrylamide, may be rendered less susceptible to aggregation at high shear (e.g. at least as high as 106 s?1) by incorporating into the structure of the particle (e.g. by copolymerisation) of a further monomer, which is not a stimulus-responsive polymer-forming monomer. The further monomer may be incorporated in an amount of up to 25 mol % based on the amount of the first monomer. Such modified polymer particles are suitable for inkjet printing applications (e.g. for printing of aqueous microgels onto low-energy surface substrates).

Abstract: Surfactants useful as dispersing aids in the preparation of compositions comprising a hydrophilic colloid having hydrophobic particles dispersed therein have the structure ##STR1## wherein M is a cation; X represents a group having the structure ##STR2## wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently represents hydrogen or alkyl; or R.sup.1 and R.sup.2 taken together represent cycloalkyl; or R.sup.3 and R.sup.4 taken together represent cycloalkyl; and, n represents 0 or 1; provided that the total number of carbon atoms in each X group is 3 or 4, and when R.sup.1 is hydrogen R.sup.2 is other than methyl. Such surfactants offer coating and photographic property advantages when incorporated in multilayer photographic materials comprising a support bearing a plurality of hydrophilic colloid layers.

Abstract: An ion-sensitive calix(4)arene compound having the formula A.sup.2 +B.sup.2 - wherein A represents a cation capable of forming a receptor-substrate complex with an anion, and B represents sulfate, nitrate or borate, characterized in that the cation is an anion receptor represented by the formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each independently a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group wherein substituents are selected from alkyl C(O)NH--, aryl C(O)NH--, alkoxy, aryloxy, alkoxycarbonyl, aryloxycarbonyl, alkylsulfonamido, arylsulfonamido, alkylcarbonyl, alkoxycarbonyl, aryloxycarbonyl, cyano and nitro;R.sup.5 and R.sup.6 are each independently H or a lower alkyl group having from 1 to 4 carbon atoms, or R.sup.3 and R.sup.4 taken together represent an ethylene bridging group; and,n is 0 or 1.

Abstract: Surfactants useful as dispersing aids in the preparation of compositions comprising a hydrophilic colloid having hydrophobic particles dispersed therein have the structure ##STR1## wherein M is a cation;X represents a group having the structure ##STR2## wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently represents hydrogen or alkyl; or R.sup.1 and R.sup.2 taken together represent cycloalkyl; or R.sup.3 and R.sup.4 taken together represent cycloalkyl; and,n represents 0 or 1;provided that the total number of carbon atoms in each X group is 3 or 4, and when R.sup.1 is hydrogen R.sup.2 is other than methyl. Such surfactants offer coating and photographic property advantages when incorporated in multilayer photographic materials comprising a support bearing a plurality of hydrophilic colloid layers.

Abstract: An ion-sensitive calix(4)arene compound having the formula A.sup.2 +B.sup.2- wherein A represents a cation capable of forming a receptor-substrate complex with an anion, and B represents sulfate, nitrate or borate, characterized in that the cation is an anion receptor represented by the formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each independently a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group wherein substituents are selected from alkyl C(O)NH--, aryl C(O)NH--, alkoxy, aryloxy, alkoxycarbonyl, aryloxycarbonyl, alkylsulfonamido, arylsulfonamido, alkylcarbonyl, alkoxycarbonyl, aryloxycarbonyl, cyano and nitro;R.sup.5 and R.sup.6 are each independently H or a lower alkyl group having from 1 to 4 carbon atoms, or R.sup.3 and R.sup.4 taken together represent an ethylene bridging group; and,n is 0 or 1.