Abstract: In producing a cyclic formal by feeding an alkylene glycol and a formaldehyde derivative as starting materials to a reaction vessel and reacting them in the presence of a catalyst, the value of amount of alkylene glycol (mole)/amount of formaldehyde derivative in terms of formaldehyde (mole) is kept at 0.02-0.95 at the time of feeding of the starting materials and at 1.05-50 at the time of reaction of the starting materials. According to this process, the amount of by-product impurities at the reaction step can be reduced, and an additional purification step of the cyclic formal is not needed or can be easily performed.

Abstract: In producing a cyclic formal by feeding an alkylene glycol and a formaldehyde derivative as starting materials to a reaction vessel and reacting them in the presence of a catalyst, the value of amount of alkylene glycol (mole)/amount of formaldehyde derivative in terms of formaldehyde (mole) is kept at 0.02-0.95 at the time of feeding of the starting materials and at 1.05-50 at the time of reaction of the starting materials. According to this process, the amount of by-product impurities at the reaction step can be reduced, and an additional purification step of the cyclic formal is not needed or can be easily performed.

Abstract: A container 2 comprising: a fixed side plate 10 placed upward on a pallet 4 so as to envelope at least three directions, a first pivotal side plate 12 mounted on an upper end of the fixed side plate 10 detachably and pivotally toward the inside of the container 2, a second side plate 24 mounted on an upper end of the first pivotal side plate 12 pivotally toward the outside of the container 2. The container 2 preferably further comprises; pivotal projections 14 provided on both sides of lower end of the first pivotal side plate 12, a frame member 8 for holding both sides of the fixed side plate 10, which has a vertical groove 18 for accepting the pivotal projection 14 to be inserted and a horizontal groove 20 formed under the vertical groove 18 for holding the pivotal projection 14 in order to lock the pivotal projection 14 from being pulled out upward.

Abstract: A translucent polypropylene film containing no .beta.-type crystallization nucleating agent which has, on at least one side, a surface layer composed of a two- or three-dimensional network structure, in which at least 1,000 network elements constituting the said network structure are present per cm.sup.2 of the film surface. The said film is obtained in such a manner that an unstretched polypropylene film having, on at least one side, a surface layer having a K value, which represents the amount of .beta.-type crystals present at a portion from the surface to a thickness of 10% in the thick-wall direction, of at least 0.1 is biaxially stretched under such conditions that the stretching temperature at the stretch initiation point is in the range of 145.degree. to 176.degree. C. and the stretch ratio in one direction is less than 8 times.