Abstract: The present invention relates to compounds containing an oxamic acid group, which show high reactivity and have stability for water and are used as paints, adhesives, and plastic materials etc. in the form of a reaction material or a resin. Since into these compounds an oxamic acid group is introduced in a part of the molecule and the oxamic acid group is an ionic functional group, the compounds show superior solubility and dispersing character in water and also, since the oxamic acid group is a group of a disappearing type with heating, the compounds do not remain, after hardening, in the hardened product. Accordingly, the hardened products obtained from these compounds are superior in water-resistant and anticorrosion properties and in durability.

Abstract: A homopolymer or a copolymer comprises a polymerizable compound represented by formula (I):A--X--COCOOR.sub.1 (I)wherein R.sub.1 represents a hydrogen atom, a C.sub.1 -C.sub.5 alkyl group or an aryl group; X represents an oxygen atom, a sulfur atom, --COO-- or --NR.sub.5 -- wherein R.sub.5 is a hydrogen atom or a C.sub.1 -C.sub.5 alkyl group; A represents a C.sub.3 -C.sub.18 alkenyl, alkynyl, alkenylaryl or alkenylaralkyl group, or a group represented by: ##STR1## wherein R.sub.2 and R.sub.3, which may be the same or different, independently represent a hydrogen atom or a C.sub.1 -C.sub.5 alkyl group; Y represents an oxygen atom or --NR.sub.4 -- wherein R.sub.4 represents a hydrogen atom or a C.sub.1 -C.sub.5 alkyl group; n is an integer of 1 to 5; m is an integer of 1 to 10; and 1 is 0 or an integer of 1 to 20;with the proviso that if Y is present, X is not --NR.sub.5 --. Additionally, disclosed are processes of preparing the homopolymer or copolymer as well as the polymerizable compound.

Abstract: A curable resin composition comprising (a) an acrylic polymer having a plurality of alicyclic epoxide functions, and (b) an amount effective to initiate the curing reaction of the acrylic polymer (a) upon heating of a heat-latent cation polymerization initiator. The composition finds its uses in coating compositions, sealants, potting and casting compositions.

Abstract: In production of a beryllium type diaphragm used for acoustic appliances such as speakers and microphones, formation of a crude beryllium plate by means of vacuum deposition is followed by hot cross rolling and hot pressing. Vacuum deposition well reduces production of undesirable impurities such as BeO and hot rolling increases density of the beryllium crystal structure obtained by the preceding vacuum deposition, both for betterment in acoustic and mechanical characteristics of the product such as sound pressure and mechanical strength.

Abstract: A curable composition comprises a compound having at least two hydroxyl groups and a homopolymer or a copolymer of a polymerizable compound represented by formula (I):A--X--COCOOR.sub.1 (I)wherein R.sub.1 represents a hydrogen atom, a C.sub.1 -C.sub.5 alkyl group or an aryl group; X represents an oxygen atom, a sulfur atom, --COO-- or --NR.sub.5 -- wherein R.sub.5 is a hydrogen atom or a C.sub.1 -C.sub.5 alkyl group; A represents a C.sub.3 -C.sub.18 alkenyl, alkynyl, alkenylaryl or alkenylaralykyl group, or a group represented by: ##STR1## wherein R.sub.2 and R.sub.3, which may be the same or different, independently represent a hydrogen atom or a C.sub.1 -C.sub.5 alkyl groups; Y represents an oxygen atom or --NR.sub.4 -- wherein R.sub.4 represents a hydrogen atom or a C.sub.1 -C.sub.5 alkyl group; n is an integer of 1 to 5;m is an integer of 1 to 10; and 1 is 0 or an integer of 1 to 20;with the proviso that if Y is present, X is not --NR.sub.5 --.

Abstract: A beryllium window comprises a disk-shaped beryllium plate containing beryllium as an essential element, a welding film partially merged into the outer peripheral portion of the beryllium plate and formed of a substance having at least one element selected from the group consisting of silver, gold, nickel and copper, and a reinforcing unit of a stainless steel, and the welding film is partially merged into the reinforcing unit, wherein the welding film fixes the beryllium plate to the reinforcing unit through diffusion welding so that the beryllium window is less deformative against heat stress.

Abstract: The invention provides a polymerizable compound represented by the formula (I):A--X--COCOOR.sub.1wherein A represents a C.sub.1 -C.sub.18 alkenyl, alkynyl, alkenylaryl or alkenylaralkyl group, or a group represented bywherein R.sub.2 and R.sub.3, which are the same or different, represent a hydrogen atom or a C.sub.1 -C.sub.5 alkyl group, Y represents an oxygen atom or --NR.sub.4 --, in which R.sub.4 represents a hydrogen atom or a C.sub.1 -C.sub.5 alkyl group, n is an integer of 1 to 5, m is an integer of 1 to 10 and 1 is 0 or an integer of 1 to 20;R.sub.1 represents a hydrogen atom, a C.sub.1 -C.sub.5 alkyl group or an aryl group; andX represents an oxygen atom, a sulfur atom, --COO-- or --NR.sub.5 --, in which R.sub.5 is a hydrogen atom or a C.sub.1 -C.sub.5 alkyl group, provided that if Y is present, X is not --NR.sub.5 --,its production and polymers prepared therefrom.