Abstract: Microcapsules for effecting an immune response, especially through agglutination reaction, comprise an antigen or antibody bound to functional groups, such as amino groups, carboxy groups, etc., on a wall surface of the microcapsules via cross linking agents, such as polyfunctional isocyanates, isothiocyanates, etc. The antigen or antibody is strongly bound to the wall surface of the microcapsules to thereby achieve excellent detection sensitivity.

Abstract: A heat sensitive recording paper is described comprising a support and a heat sensitive recording layer containing a colorless or light colored electron-donating dye and a phenolic compound, said recording paper containing a sodium or potassium salt of a monovalent or divalent organic carboxylic acid having from 2 to 15 carbon atoms in at least one of the support and the recording layer, to obtain a desired gain in conductivity without being attended by a drop in coating facility.

Abstract: A heat-sensitive recording paper is described, comprising a support having formed thereon a heat-sensitive recording layer containing a colorless or pale-colored electron donating dye precursor and an electron accepting substance that reacts with said electron donating dye precursor to develop color, and an overlying protective layer containing a water-soluble polymeric binder and a pigment, wherein the back side of the support is provided with a backcoat layer containing an alkali salt of a styrene-maleic acid copolymer.

Abstract: A process for producing a microcapsule diagnostic material utilizing passive agglutination which comprises binding an antigen or antibody onto a microcapsule wall negatively charged, in an acidic solution is provided. The microcapsule diagnostic material thus produced has an extremely high sensitivity in agglutination without causing any non-specific agglutination.

Abstract: A heat-sensitive recording paper is disclosed, comprising a base having thereon (a) a heat-sensitive color forming layer containing a substantially colorless electron donating dye and an acid substance capable of forming a coloration by coming into contact with said dye upon heating, wherein a coating layer containing a binder comprising modified polyvinyl alcohol containing silicon atoms in the molecule and at least one of colloidal silica and amorphous silica is provided on said color forming layer.

Abstract: A process for producing a heat-sensitive recording paper is disclosed. The process involves pretreating base paper by a high-frequency corona discharge. The base paper treated in this manner can be utilized in producing a heat-sensitive recording material by providing a heat-sensitive layer thereon. By subjecting the base paper to the high-frequency corona discharge treatment the base paper can be uniformly coated with a heat-sensitive recording material without leaving any blank spaces thereon.

Abstract: A heat sensitive recording material is described, which has on a support a heat sensitive coloring layer containing (a) an electron-donating colorless dye, (b) an electron-accepting compound, and (c) at least one ether compound represented by formula (I) or (II) ##STR1## wherein X represents a hydrogen atom, a halogen atom, an alkyl group containing not more than 6 carbon atoms, or an alkoxy group containing not more than 6 carbon atoms; Y represents a hydrogen atom, a halogen atom, an alkyl group containing not more than 6 carbon atoms, or an alkoxy group containing not more than 6 carbon atoms; and R represents a hydrogen atom or an alkyl group containing not more than 18 carbon atoms.

Abstract: A heat-sensitive recording paper is disclosed. The paper is comprised of a support base having provided thereon, an almost colorless electron donating dye, an organic acid capable of coloration upon contacting the dye and a phenolic compound. The phenolic compound is represented by the general formula (I): ##STR1## wherein R.sub.1 is a branched alkyl group having 3 to 8 carbon atoms, R.sub.2 is a hydrogen atom or a branched alkyl group having 3 to 8 carbon atoms and R.sub.3 is a hydrogen atom or a methyl group. The paper is capable of producing clear images without fogging and the images produced undergo a reduced amount of fading due to the influence of humidity or heat.

Abstract: A heat-sensitive recording paper which is comprised of a support base having a heat-sensitive color forming layer thereon is disclosed. The layer contains a colorless or faint color electron donating dye, a bisphenol and a straight chain fatty acid amide. The recording sensitivity of the paper is greatly increased by incorporating a phenol derivative having the general formula ##STR1## wherein R is an alkyl group or an aralkyl group and Y represents a phenyl group, an alkyl group, a cycloalkyl group or a halogen atom.

Abstract: A heat-sensitive recording material comprising a heat-sensitive color forming layer on a base is disclosed. The color forming layer contains an electron donating colorless dye and an organic acid to which a heat-fusible substance having a melting point in the range of from 60.degree. to 150.degree. C. is fusion-bonded. A process for producing such recording material by applying to a base a coating solution containing a developer for heat-sensitive recording is also disclosed. The developer is prepared by the steps of dispersing in a dispersion medium a heat-fusible substance having a melting point in the range of from 60.degree. C. to 150.degree. C. and an organic acid, heating the resulting dispersion under conditions that form a turbulent flow, and cooling the heated dispersion to ordinary temperatures.

Abstract: A microcapsule coated sheet for pressure sensitive copying paper, which comprises a support having provided thereon, in sequence, a first coating layer primarily comprising (1) microcapsules retaining an oil containing an electron donating color former dissolved or dispersed therein and (2) inorganic or organic solid fine particles which do not substantially form color when in contact with said electron donating color former, and a second coating layer primarily comprising an adhesive.

Abstract: A heat-sensitive recording paper is disclosed. The paper is comprised of a support base which is made of a paper having a density 0.9 g/cm.sup.3 or less and a heat-sensitive recording layer coated on the support base. The surface of the heat-sensitive recording layer has an optical contact ratio of 7% or more. By utilizing the particularly disclosed support base paper and adjusting the optical contact ratio of the surface of the heat-sensitive recording layer, the resulting recording paper can give high heat conductivity between the surface of the recording layer and a recording element. Accordingly, the recording paper has a fast response speed and can produce a high density image without disadvantages such as increased fog formation.

Abstract: A microcapsule sheet is disclosed. At least one surface of the base paper has a coating produced from a solution that contains microcapsules each containing an electron donating color former, a binder whose solid content is from 20 to 50 parts by weight based on 100 parts by weight of the solid content of the microcapsules, a protective agent and a surfactant having a hydrophobic atomic group of the formula: ##STR1## wherein R.sub.1 and R.sub.2 are each an aliphatic hydrocarbon having 2 to 20 carbon atoms or aromatic hydrocarbon having 6 to 20 carbon atoms.

Abstract: A heat-sensitive recording material comprising a heat-sensitive color forming layer on a base is disclosed. The color forming layer contains an electron donating colorless dye and an organic acid to which a heat-fusible substance having a melting point in the range of from 60.degree. to 150.degree. C. is fusion-bonded. A process for producing such recording material by applying to a base a coating solution containing a developer for heat-sensitive recording is also disclosed. The developer is prepared by the steps of dispersing in a dispersion medium a heat-fusible substance having a melting point in the range of from 60.degree. C. to 150.degree. C. and an organic acid, heating the resulting dispersion under conditions that form a turbulent flow, and cooling the heated dispersion to ordinary temperatures.

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: Microcapsules with a melamine-formaldehyde or urea-formaldehyde resin capsule shell are produced by adding in advance a polyvalent isocyanate, a polyvalent isothiocyanate or a prepolymer thereof to the hydrophobic oily liquid to be encapsulated, emulsifying the hydrophobic oily liquid in an aqueous solution of a water-soluble polymer, adding an aqueous solution of melamine and formaldehyde or a precondensate thereof or urea and formaldehyde to the emulsion, and polymerizing the melamine and formaldehyde or a precondensate thereof or the urea and formaldehyde.

Abstract: Antigen- or antibody-bound microcapsules are employed for immunological assay of biochemical components having immunological activity. The microcapsule system provides high detection sensitivity, high accuracy and excellent reproducibility in immunological assay, without causing non-specific reaction. The microcapsules can be labelled with isotopes, enzymes, etc., for use in quantitative assays of trace amounts of biochemical components.

Abstract: A desensitizer composition for color developing agents which color upon reaction with colorless compounds comprising an adduct of an amine represented by the following general formula (I) with one or more alkylene oxides, said one or more alkylene oxides comprising at least 40 mole % butylene oxide: ##STR1## wherein R represents a hydrogen atom or an alkyl group, m represents zero or an integer from 1 to 8, and n represents an integer from 1 to 12. A method of using the same is also disclosed.

Abstract: A heat-sensitive recording sheet which comprises a support, a white or light-colored pigment coating layer having an oil absorption determined by JIS K5101 of 75 ml/100 g or more on the support, and a heat-sensitive color forming layer comprising an electron donor colorless dye and an electron acceptor compound on the coating layer.

Abstract: A pressure-sensitive recording paper comprising a support having coated thereon a layer of color former, said color former dissolved in at least one compound represented by the following formula: ##STR1## wherein n is an integer of 1 to 8, R and R' each represent a member selected from the group consisting of alkyl groups containing one to eight carbon atoms, and a hydrogen atom, p and q represent the number of alkyl groups, p+q being an integer of 1 to 3, and R and R' may be the same.