Abstract: A block copolymer includes an end group, a block that binds to the end group, and a block that does not bind to the end group. The block that does not bind to the end group contains at least one non-crosslinkable constitutional unit represented by the formula (X) and/or at least one non-crosslinkable constitutional unit represented by the formula (Z). At least one of formulas (i) XI>XII, (ii) ZI>ZII and (iii) XI+ZI>XII+ZII is satisfied when the total number of non-crosslinkable constitutional units represented by formulas (X) and (Z) in the block that does not bind to the end group are represented by XI and ZI, respectively, and the total number of non-crosslinkable constitutional units represented by formulas (X) and (Z) in the block that binds to the end group are represented by XII and ZII, respectively.

Abstract: A block copolymer includes an end group, a block that binds to the end group, and a block that does not bind to the end group. The block that does not bind to the end group contains at least one non-crosslinkable constitutional unit represented by the formula (X) and/or at least one non-crosslinkable constitutional unit represented by the formula (Z). At least one of formulas (i) XI>XII, (ii) ZI>ZII and (iii) XI+ZI>XII+ZII is satisfied when the total number of non-crosslinkable constitutional units represented by formulas (X) and (Z) in the block that does not bind to the end group are represented by XI and ZI, respectively, and the total number of non-crosslinkable constitutional units represented by formulas (X) and (Z) in the block that binds to the end group are represented by XII and ZII, respectively.

Abstract: A method is provided for producing a compound, including a step of mixing a compound (1) having one or two leaving groups, a compound (2) having one or two boron atom-containing leaving groups, an organic base (P), and at least one selected from a phase transfer catalyst and an organic base (Q) larger in the number of carbon atoms than the above-mentioned organic base in the presence of a transition metal catalyst. The method thereby performs a coupling reaction between the above-mentioned compound (1) and the above-mentioned compound (2).

Abstract: A method is provided for producing a compound, including a step of mixing a compound (1) having one or two leaving groups, a compound (2) having one or two boron atom-containing leaving groups, an organic base (P), and at least one selected from a phase transfer catalyst and an organic base (Q) larger in the number of carbon atoms than the above-mentioned organic base in the presence of a transition metal catalyst. The method thereby performs a coupling reaction between the above-mentioned compound (1) and the above-mentioned compound (2).

Abstract: A mid-span branching method for an optical path including a multi-fiber optical cable which is constituted by a multi-fiber ribbon with a plurality of optical fibers arranged in a plane and integrated with a common coating, includes the first step of exposing an intermediate portion of the multi-fiber ribbon from the multi-fiber optical cable (step 101), the second step of extracting the exposed multi-fiber ribbon (step 102), the step of separating at least one single-core optical fiber from the extracted multi-fiber ribbon (step 103), and the step of connecting the single-core optical fiber separated from the multi-fiber optical cable to a single-core optical fiber branched from a branch cable (steps 104, 105).

Abstract: The present invention provides a separating tool for separating a multi-core ribbon fiber obtained by arranging a plurality of optical fibers in a plane and integrating the fibers with a common coating into single-core optical fibers, and includes a fiber accommodating means for accommodating the multi-core ribbon fiber in an accommodating area, a fiber holding means for holding the multi-core ribbon fiber in the accommodating area, a scratching means for forming a scratch on a surface of a common coating of the multi-core ribbon fiber held by the fiber holding means, an arrangement defining means for changing an pitch position of the scratching means, and a shearing force applying means for applying a shearing force to the multi-core ribbon fiber along the scratch formed by the scratching means.