Abstract: Dynamic properties of vulcanized rubber are improved, without accelerating scorching property remarkably nor deteriorating flex-cracking resistance, by incorporating in a filler-containing natural or synthetic rubber composition, a dinitrodiamine derivative represented by the general formula ##STR1## wherein A represents a divalent aliphatic group, a divalent cycloaliphatic group, a divalent aromatic group or a group represented by the formula --CH.sub.2 --X--CH.sub.2 --, wherein X represents a cycloalkylene group or a phenylene group, provided that if A represents a cycloaliphatic group or an aromatic group, the two carbon atoms in A which are bonding to the nitrogen atom are not vicinal to each other; R and R' independently represent hydrogen atom or an alkyl group having 1-12 carbon atoms and may conjointly form a ring; and R" represents hydrogen atom, an aliphatic group, a cycloaliphatic group or an aromatic group. A process for producing the dinitrodiamine derivatives is also disclosed.

Abstract: A stabilized resin composition comprising a resin, a piperidine derivative represented by the formula (III) ##STR1## wherein R.sub.1 is a hydrogen atom or an alkyl group having 1 to 3 carbom atoms; R.sub.2 is a hydrogen atom or an alkyl group having from 1 to 2 carbon atoms; and R.sub.3 and R.sub.4 are each independently an alkyl group having 1 to 12 carbon atoms, a phenol-type antioxidant and a sulfur-containing antioxidant. The composition simultaneously meets heat resistance, oxidation resistance and light resistance requirements.

Abstract: A stabilizer for synthetic resins containing as an effective ingredient a hindered piperidine compound represented by the general formula: ##STR1## wherein R.sub.1 represents a C.sub.1 -C.sub.18 alkyl group, R.sub.2 represents a hydrogen atom or a C.sub.1 -C.sub.4 alkyl group, n represents an integer of 1 to 12, and C.sub.n H.sub.2n represents a straight-chain or branched alkylene group.

Abstract: A vulcanization accelerator containing as an active ingredient a compound having at least one dithiocarbamoyl group, which is shown by the following general formula [I], a means for accelerating vulcanization by adding said compound and rubber products having improved quality which is attained by using said compound as a vulcanization accelerator: ##STR1## wherein R.sup.1 stands for an alkyl group having one to 12 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms or an aralkyl group having 7 to 13 carbon atoms, A stands for a group shown by the formula ##STR2## or metallic atom; in which x represents zero or an integer of 1 to 5, R.sup.

Abstract: The present invention relates to a piperidine derivative represented by the general formula (I), ##STR1## wherein R.sub.1 is a uni- or divalent carboxylic acid residue, R.sub.2 is a hydrogen atom or a C.sub.1 -C.sub.3 alkyl or C.sub.1 -C.sub.18 acyl group, l is an integer of 1 to 3 and n is 1 or 2,its production and a stabilizer for organic substances containing it as an effective ingredient.

Abstract: The present invention relates to a piperidine derivative represented by the general formula (I), ##STR1## wherein R.sub.1 and R.sub.2 independently represent a hydrogen atom or a C.sub.1 -C.sub.3 alkyl or C.sub.2 -C.sub.20 acyl group, R.sub.3 represents a hydrogen atom or a C.sub.1 -C.sub.20 alkyl, C.sub.6 -C.sub.20 aryl, C.sub.7 -C.sub.20 aralkyl or C.sub.2 -C.sub.20 acyl group, and l represents 1 to 3, and a stabilizer for organic substances containing said piperidine derivative as an effective ingredient.

Abstract: A normally liquid stabilizer for rubber or urethane resin, obtained by reacting hydroquinone with a mixture of aromatic amines of the formula: ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3, independently of each other, are hydrogen or C.sub.1-18 alkyl, said aromatic amine mixture containing 7-26 weight % of p-ethylaniline and 8-40 weight % of 2,4-xylidine.

Abstract: 2,2,4-Trimethyl-1,2-dihydroquinoline polymer containing 25% by weight or more of the dimer is effectively prepared by the polymerization of 2,2,4-trimethyl-1,2-dihydroquinoline monomer in the presence of hydrochloric acid, the concentration of hydrochloric acid being from 15 to 25% by weight, and the amount of hydrochloric acid being 0.2 to 0.5 mole per mole of the total of the monomer and impurity amines contained in the monomer. The polymer is useful as an antioxidant for rubber.