主权项 |
1. A melt bag which is formed using a resin composition,
wherein the resin composition consists of: a propylene/1-butene copolymer (A), an ethylene/1-butene copolymer (B), and optionally, an additive which is at least one selected from the group consisting of antioxidants, lubricants, heat stabilizers, UV absorbers, anti-blocking agents, slip agents and antistatic agents, wherein the weight ratio of these copolymers (A)/(B) is in the range of 90/10 to 70/30, wherein the propylene/1-butene copolymer (A) is produced by copolymerizing propylene and 1-butene in the presence of a metallocene catalyst that contains a transition metal compound (1a) represented by Formula (1a) below, has (1) a melting point (Tm) of 40 to 85° C. as measured by differential scanning calorimetry (DSC) and contains (2) structural units derived from propylene in an amount of 60 to 80 mol % and structural units derived from 1-butene is an amount of 20 to 40 mol %, and wherein, in Formula (1a), R1 and R3 are each a hydrogen atom; R2 and R4 are each selected from hydrocarbon groups and silicon-containing groups and may be the same or different from each other R3, R6, R7, R8, R9, R10, R11, R12, R13 and R14 are each selected from hydrogen atom, hydrocarbon groups and silicon-containing groups and may be the same or different from one another; adjacent substituent groups of R5 to R12 may be linked with each other to form a ring; R13 and R14 are the same or different from each other and may be linked together to form a ring; M is a Group 4 transition metal; Y is a carbon atom; Q is a halogen, a hydrocarbon group, an anionic ligand or a neutral ligand capable of coordination via a lone pair of electrons, and may be the same or different when plural; and j is an integer ranging from 1 to 4, and wherein the ethylene/1-butene copolymer (B) has (1) a melting point (Tm) of 40 to 85° C. as measured by differential scanning calorimetry (DSC) and contains (2) structural units derived from ethylene in an amount of 50 to 95 mol % and structural units derived from 1-butene in an amount of 5 to 50 mol %. |