Abstract: A color developing ink containing a phenolic resin or a metal salt of an aromatic carboxylic acid and an alcohol having from 10 to 20 carbon atoms.

Abstract: A method for preparing microcapsules comprising polymerizing urea and formaldehyde in the presence of an anionic polyelectrolyte and an ammonium salt of an acid and forming a wall membrane of a urea/formaldehyde resin around droplets of a hydrophobic oily liquid.

Abstract: A capsule solution is prepared by polymerizing urea and formaldehyde in the presence of gum arabic to thereby form a urea-formaldehyde resin wall around a hydrophobic oily solution. The use of gum arabic reduces the viscosity of the capsule solution, the capsule solution which is obtained is particularly suitable for preparing pressure sensitive recording sheets.

Abstract: A recording sheet comprising a support having thereon a layer of a color developer capable of forming a developed color image in the presence of a color former, wherein the color developer layer contains (1) a dimer of a compound of the formula (I): ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3, which may be the same or different, each represents a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, and n is an integer of 1 to 4, as a color developer, and (2) an oil adsorptive inorganic pigment.

Abstract: A pressure-measuring sheet comprising a support having thereon a layer of microcapsules containing an electron-donating color former capable of forming a color on contact with an electron-accepting color developer, the microcapsules comprising a mixture of at least two groups of microcapsules having different ratios .delta./D of the number average wall thickness .delta. of the microcapsules to the volume average particle diameter D of the microcapsules and having a Ps value difference of about 50 to about 1,000 kg/cm.sup.2. Various planar and linear pressures and the distributions thereof can be measured by the pressure-measuring sheet utilizing changes in the densities of colors formed upon the application of pressures to the microcapsule layer because the color density changes are directly related to the pressures applied.

Abstract: A desensitizing composition for a color developer capable of coloring a substantially colorless color former, which desensitizing composition contains a compound represented by the following general formula (I) ##STR1## wherein R has from 2 to 20 carbon atoms and represents an alkyl group, an alkenyl group, an aryl group, an aralkyl group or a ##STR2## group; m is 0 or an integer of 1 to 3; n is an integer of 2 to 6; the sum of a, b and c is an integer of 3 to 100, the sum of a, b, c and d is an integer of 4 to 100; the sum of p, q and r is an integer of 3 to 100; and the sum of p, q, r and s is an integer of 4 to 100.

Abstract: A method of desensitization of a color developer to form a color upon reaction with a color former which comprises coating a photocurable composition containing a photocurable compound on a color developer sheet and then irradiating the coated surface with light to cure the photocurable compound and thereby desensitize the color developer surface.

Abstract: A process for producing a developer sheet for a pressure-sensitive recording paper which comprises dissolving an oil-soluble developer in an organic solvent, emulsifying the solution in water to provide an oil-in-water emulsion, and then coating on or incorporating into a support the resulting emulsion is disclosed.

Abstract: A method of forming low porosity microcapsule films which comprises chemically or ionically binding a water soluble or water dispersible heterocyclic amine to a microcapsule film forming material, or depositing the heterocyclic amine alone or a water insoluble material formed by reaction with the amine onto the microcapsule film.

Abstract: A method for fanning multi-ply sheets into units thereof, which comprises applying the adhesive composition to one side of a stack of multi-ply sheets, e.g., pressure-sensitive copying sheet units, and separating each unit of the sheets.

Abstract: A desensitizer composition for desensitizing a developer against coloring a substantially colorless color former comprising as a desensitizing agent at least one N-(aminoalkyl)-lactam of the formula ##STR1## wherein n is 2 to 11, m is 2 to 6 and each methylene group can be substituted with an alkyl or aryl group, or a derivative thereof. The desensitizing composition exhibits a strong desensitization effect.

Abstract: A pressure sensitive recording sheet having thereon a layer of fine oil microcapsules produced by the process which comprises dispersing or emulsifying finely in a polar solvent an oily liquid containing a substantially colorless color former capable of reacting with a developer to form a colored product and a polyisocyanate adduct having a free isocyanate group and adding to the dispersion or emulsion of the oil droplets a polyamine or a polyamine adduct having a free amino group as a polymerization promotor, whereby the polymerization of the polyisocyanate adduct is caused from the outer side of each oil droplet to encapsulate the oil droplet by the insolubilized polyisocyanate adduct. By this process the size of the microcapsules can be controlled quite easily.

Abstract: In a process for producing microcapsules which comprises microencapsulating hydrophobic oil droplets by complex coacervation using at least two hydrophilic colloids having opposite electric charges and being ionizable in water with at least one of the colloids being gellable, the improvement comprising hardening the coacervate wall by the presence of an oxidation product of a polysaccharide as a hardening agent and adjusting the pH.

Abstract: A desensitizer composition containing at least one of an amidine represented by the general formula (I) ##STR1## wherein R.sub.1 and R.sub.2 each represent an alkyl group having 1 to 8 carbon atoms, R.sub.1 and R.sub.2 can form a C.sub.2 to C.sub.11 ring which can be substituted by alkyl groups having 1 to 4 carbon atoms, and n represents 2 to 6, or a derivative of the amidine.

Abstract: A method of desensitizing comprising contacting a color developer capable of forming a color upon contact with a color former with a desensitizing composition comprising the reaction product of (a) an alkylsiloxane, an alkylsilmethylene or an alkylsilane, and (b) an alkylene oxide or an alkylene imine (wherein the alkylene imine may be a tertiary amine).

Abstract: A pressure measurement sheet comprises a support and a layer containing microcapsules provided thereon, wherein the ratio of the number average wall thickness (.delta.) to the volume average particle diameter (D) of the microcapsules lies in the range: .delta./D = about 1.5 .times. 10.sup.-.sup.3 to about 3.0 .times. 10.sup.-.sup.2. A method of measuring pressure by the use of the pressure measurement sheet described above comprising the steps of contacting the pressure measurement sheet with the area to be measured, applying pressure to form color and determining the applied pressure from changes in optical densities or hues, where the color is formed through contact under pressure between a layer containing microcapsules and a layer containing an adsorbent.

Abstract: A process for the production of microcapsules comprising bonding chemically or physically a heterocyclic diamine, which is soluble or dispersible in water, to an organic compound in a polar solvent to thereby form a substance, which is insoluble in the polar solvent, and then depositing the substance directly on the surface of particles or droplets of a hydrophobic core material.

Abstract: In a process for preparing oil-containing microcapsules comprising cooling a coacervate dispersion of a gelatin-containing colloid deposited around individual oil droplets to cause gelation of the colloid and subsequently hardening the gelled colloid by adding to the dispersion a hardening agent and adjusting the pH to the alkaline region, the improvement which comprises adding to the dispersion, after gelation but prior to hardening, an aqueous solution of an anionic high molecular weight electrolyte and an aqueous solution of an anionic surface active agent. Specific electrolytes and specific surface active agents are disclosed.

Abstract: In a process for producing oil-containing microcapsules by coacervation comprisingA. introducing a fine powder or hydrophobic liquid into a high molecular weight electrolytic wall-forming colloid;B. coacervating the resulting dispersion or emulsion;C. cooling the resulting coacervate to gel it and form the wall of said microcapsules; andD. hardening said wall of said microcapsules; the improvement which comprises adding a phenolic compound to the system.

Abstract: In a process for hardening microcapsules produced by microencapsulating hydrophobic oil droplets using a complex coacervation process with gelatin as one of the hydrophilic colloids: including the steps of1. emulsifying a water-immiscible oil in an aqueous solution of at least one first hydrophilic colloid ionizable in water and admixing an aqueous solution of at least one second hydrophilic colloid having an electric charge opposite to that of said first colloid,2. causing coacervation of said colloids to occur by adding water thereto or adjusting the pH thereof to form coacervates,3. cooling said coacervates to cause gelling thereof,4. adjusting the pH to alkalinity and adding a hardening agent sequentially or simultaneously,5. increasing the temperature so as to cause hardening, the improvement wherein glyoxal or glutaraldehyde in combination with formaldehyde is present during step (4).