Abstract: A recording sheet comprising a support and a developer layer, which develops color images on reacting with a color former, on the support containing a dimer of the compound represented by the formula: ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 each represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group, and n is 1 to 4.

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 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 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: This invention relates to a closable counter device for a vertical wall structure such as a door of a house or an office or room in a building and more particularly to a closable counter device on a vertical wall such as a door adapted to conveniently communicate with a visitor or visitors or to deliver an article or articles therethrough in the condition of opening the counter device while the door is latched without imparting any discomfort to the visitor or visitors and in a safe manner in connection with prevention of crimes as well as in connection with prevention of privacy.

Abstract: A process for separating a number of sheets into groups of sheets comprising coating an adhesive composition on an edge of a stack of the sheets fanning the sheets. The adhesive composition contains a naphthalene sulfonic acid-formaldehyde condensation product and a water-soluble polymer material.

Abstract: A method of desensitizing a color developer used in a color forming reaction with a color former comprising contacting a desensitizer composition containing polypropylene glycol having an average molecular weight of about 400 to 5000 with the color developer.

Abstract: A color developer is disclosed which, when contacted with a color former, is capable of forming a distinct color, the color developer comprising a metallic compound of an aromatic carboxylic acid. Suitable metals are, for example, those of the following groups of the Periodic Table: Ib, IIa, IIIb, IVb, VIa, VIIa and VIII. A recording sheet employing the color developer is also disclosed.