Abstract: An improved method of producing frozen food including at least two steps of freezing. Food is frozen at a temperature in the neighborhood of a temperature at which the maximum crystallization of ice takes place. Then, the food is processed, and frozen again at a temperature which is not higher than -10.degree. C.

Abstract: A cap for a fuel tank has a cap body for screwing into the filler neck of the fuel tank with an "O" ring interposed therebetween, and a lid member for mating to the cap body, both the lid member and the cap body having coacting structure for mutual interengagement to maintain the lid member normally mated to the cap body but separable in break-away relationship from the cap body to leave the cap body intact within the filler neck upon application of external force, such as through collision, to the lid member. The coacting structure may take the form of engaging recesses, holes or grooves on one member and of engaging projections, tabs or pins on the other member.

Abstract: Novel tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxymethyl)methane having a novel crystal structure characterized by the fact that its X-ray diffraction pattern obtained by X-ray analysis using Cu-K.sub..alpha. rays shown a sharp peak at a diffraction angle 2.theta.=10.90.degree.. The above compound can be prepared by (a) transesterifying methyl or ethyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate with pentaerythritol in the presence of a compound of the formula ##STR1## wherein R.sub.1 and R.sub.2 each represent an alkyl group having 1 to 6 carbon atoms,(b) treating the resulting tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxymethyl)methane with a lower alkanol capable of forming a molecular adduct compound therewith to convert it into the corresponding molecular adduct compound, and (c) recrystallizing the molecular adduct compound from ethanol as a solvent.

Abstract: A process for producing a linear unsaturated dimer of .alpha.-alkyl styrenes by heating .alpha.-alkyl styrenes in the presence of a silica-alumina catalyst, said catalyst consisting of alumina and silica in a weight ratio of 83/17.ltoreq.Al.sub.2 O.sub.3 /SiO.sub.2 .ltoreq.96/4 and being substantially free of alkali is disclosed.

Abstract: A muffler comprising: an upper case provided at the opposite ends with semi-cylindrical inlet and outlet sections respectively and having an outwardly raised central portion and an integral flange-like edge portion; a lower case joined at a flange-like edge portion to that of said upper case and substantially symmetrical with said upper case with respect to the underside thereof; an exhaust inlet tube forming member having at least a semi-cylindrical inlet section inserted in a cylindrical inlet formed by the inlet sections of said upper and lower cases joined together and a gutter-like guide section connected to said inlet section and being joined to said upper case, lower case or both of them, said forming member being provided adjacent to an end thereof with a perforated portion; and an exhaust outlet tube forming member having at least a semi-cylindrical outlet section fitted in a cylindrical outlet formed by the outlet sections of said upper and lower cases and a gutter-like guide section connected to sa