Abstract: A laminate comprising an inner layer containing an acid/base indicator and an outer layer containing no acid/base indicator, wherein the inner layer is capable of undergoing a color change upon its contact with an acid or an alkali.

Abstract: A process for preparing an ethylene polymer by a two-stage polymerization of ethylene or ethylene and an .alpha.-olefin in an inert hydrocarbon at 50.degree.-100.degree. C. using a coordination polymerization catalyst containing a solid component and an organoaluminum compound, said solid component containing a transition metal compound, which process comprises:(a) in a first stage, producing 10-90% by weight based on the total polymer quantity of a polymer having a melt index in the range of 0.0001 to 0.5 g/10 min as measured according to ASTM D 1238-73, Condition E, using as said solid component a solid product obtained by supporting chromium trioxide or a compound which on calcining forms chromium oxide at least partially, on an inorganic oxide carrier followed by calcining, and using as said organoaluminum compound a compound of the general formula ##STR1## wherein R is a hydrocarbon radical having 1 to 18 carbon atoms and n is 2.ltoreq.n.ltoreq.

Abstract: A process is disclosed for acceleratively vulcanizing rubber. Starting rubber, natural or synthetic, is combined with specified amounts of a selected accelerator whereby vulcanization characteristics can be greatly improved. Such accelerator has its source of supply from serums by-produced upon treatment of natural rubber latexes.

Abstract: Disclosed is polyethylene composition having excellent environmental stress cracking resistance (ESCR) and giving molded articles with good surface properties.This composition comprises a blend of two specific types of polyethylene selected with due consideration for their molecular weight distribution in addition to their molecular weights, so that it has excellent melt tension, ESCR and moldability. Accordingly, it can suitably be used in blow molding and extrusion molding to produce molded articles with no shark skin, as well as vessels of very large size.This composition is formed by blending (A) polyethylene obtained according to a two-step polymerization process using a Ziegler catalyst containing magnesium and titanium, and (B) high-molecular-weight polyethylene obtained with the aid of a chromium-containing catalyst, in a specified proportion.

Abstract: Provided is an olefin polymerization catalyst comprising the combination of:[I] a solid catalyst component comprising a solid material obtained by contacting the following components (1) to (4) and a titanium compound (5) supported on said solid material:(1) a magnesium halide,(2) a compound represented by the general formula ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 are each a hydrocarbon radical having 1 to 24 carbon atoms, alkoxy, hydrogen, or halogen, R.sup.4 is a hydrocarbon radical having 1 to 24 carbon atoms and n is 1.ltoreq.n.ltoreq.30,(3) a compound represented by the general formula ##STR2## wherein R.sup.5 is hydrogen, halogen, or a hydrocarbon radical having 1 to 24 carbon atoms, R6 is a hydrocarbon radical having 1 to 24 carbon atoms, and r, p and q are integers selected from the following ranges: 1.ltoreq.r.ltoreq.3, 0.ltoreq.p<6, 0.ltoreq.q<6, provided 1.ltoreq.r+p+q<6, and(4) a compound represented by the general formula R.sup.7 -O-R.sup.8 wherein R.sup.7 and R.sup.

Abstract: Provided is a process for preparing a polyolefin, characterized by polymerizing at least one .alpha.-olefin in the presence of a catalyst which comprises the combination of:[I] a solid catalyst component comprising a solid substance obtained by contacting the following components (1) through (3) with one another and (4) a titanium compound supported on said solid substance:(1) a magnesium halide,(2) a compound represented by the general formula ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 are each a hydrocarbon radical having 1 to 24 carbon atoms, an alkoxy group, hydrogen, or a halogen atom, R.sup.4 is a hydrocarbon radical having 1 to 24 carbon atoms and n is 1.ltoreq.n.ltoreq.30, and(3) at least one compound selected from the group consisting of:(a) compounds represented by the general formula ##STR2## wherein R is hydrogen, a halogen atom, or a hydrocarbon radical having 1 to 24 carbon atoms, and r, p and q are integers satisfying the following conditions:1.ltoreq.r.ltoreq.3, 0.ltoreq.p<6, 0.ltoreq.

Abstract: The invention is concerned with a pressure-sensitive, electrically conductive composite sheet which enables a free selection of the pressure sensitivity, and which exhibits a large change in resistance upon compression. The sheet comprises an electrically conductive elastomer sheet obtained by blending an elastic high-molecular material with electrically conductive particles, and forming a dot pattern over at least one surface of the electrically conductive elastomer sheet, the dot pattern being composed of an electrically insulating material and having a form that satisfies the following requirements:______________________________________ Diameter of dots R = 0.3 to 1.5 mm Thickness of dots d = 0.01 to 0.10 mm Distance between centers l = (0.1 to 3.

Abstract: Using a catalyst comprising (1) a solid substance which contains magnesium and titanium, (2) an organometallic compound and (3) an electron donor, there are polymerized ethylene, propylene and 1-butene to obtain a soft or semi-hard terpolymer of low crystallinity containing 75.2 to 91.5 mol % propylene, 7.5 to 14.9 mol % ethylene and 1.0 to 9.9 mol % 1-butene.

Abstract: This invention provides a process for preparing polyolefins using a new catalyst. According to this invention, .alpha.-olefins can be polymerized or copolymerized to have good stereoregularity and at a high activity by the use of such new catalyst. The new catalyst used in this invention consists of [A] a solid component obtained by contacting (1) a magnesium oxide, (2) an aluminum trihalide, (3) a hydroxy compound represented by the general formula ROH wherein R is an organic radical having 1 to 20 carbon atoms and (4) a titanium halide and/or an addition product of a titanium halide and an aromatic carboxylic acid ester, and [B] an organometallic compound and/or an addition product of an organometallic compound and an aromatic carboxylic acid ester; or it consists of the solid component of the above [A], the organometallic compound and/or the addition product of an organometallic compound and an aromatic carboxylic acid ester of the above [B], and [C] an aromatic carboxylic acid ester.

Abstract: According to this invention, there is provided a process for preparing a low-crystalline soft or semi-hard copolymer, characterized in that 90 to 98 mole % of propylene, 0.2 to 9 mole % of ethylene and 0.2 to 9 mole % of a straight-chained (.alpha.-olefin having not less than four carbon atoms are copolymerized using a catalyst, said catalyst comprising (1) a solid substance containing magnesium and titanium, (2) an organometallic compound and (3) an electron donor.

Abstract: According to this invention, there is provided a process for preparing a non- or low-crystalline soft copolymer, characterized in that 50 to 98 mole % of propylene, 0.2 to 30 mole % of ethylene and 0.2 to 45 mole % of a straight-chained .alpha.-olefin having not less than four carbon atoms are copolymerized using a catalyst, said catalyst comprising (1) a solid substance containing magnesium and titanium and (2) an organometallic compound.

Abstract: According to this invention there is provided a process for polymerizing or copolymerizing olefins using a catalyst consisting of:[A]a solid component obtained by contacting(1) a reaction product resulting from heat reaction of a magnesium oxide and an aluminum trihalide with(2) a titanium halide and/or an addition product of a titanium halide and an aromatic carboxylic acid ester, and[B]an organometallic compound and/or an addition product of an organometallic compound and an aromatic carboxylic acid ester,or alternatively, using a catalyst consisting of acid components [A] and [B] plus [C] an aromatic carboxylic acid ester.

Abstract: Rubber compositions containing relatively large amounts of benzoic acid or monohydroxy benzoic acid providing vulcanized rubber products having improved adhesion to metallic or fibrous materials and an improved chipping and cutting resistance. This is a continuation of application Ser. No. 588,047, filed June 18, 1975, now abandoned.