BIAXIALLY-ORIENTED POLYPROPYLENE FILM

• Main Authors: NAKAGAWA TAKUJI, MURASE SHIGEO, SHISHIDO YUICHI, MATSUI AKIMITSU, TANIGUCHI YOSHIKAZU, OI TORU, ISHIWATARI TADAKAZU
• Format: Patent
• Language: English; Japanese
• Published: 18.02.2021
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; CHEMISTRY; COMPOSITIONS BASED THEREON; GENERAL PROCESSES OF COMPOUNDING; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL; WORKING-UP

To provide a biaxially-oriented polypropylene film useful as a protective film with excellent detachability, in which contamination, voids and air voids are hardly caused, and/or a non-silicone separator film.SOLUTION: A biaxially-oriented polypropylene film is formed from a polypropylene resin with a melt flow rate of 1.5 g/10 min to 6.0 g/10 min, comprising: a surface roughness of at least one surface with (a) 0.03 to 0.10 μm in center line roughness (Ra) and (b) 0.3 μm to 1.0 μm in maximum height (Rmax); a layer in which the number of fish eyes having a size (long diameter) of 50 μm or more is 100 pieces/m2 or less; and a thickness of 5 μm to 60 μm.SELECTED DRAWING: Figure 1 【課題】剥離性に優れ、汚染やボイド、エアーボイドの発生が少ない保護材フィルム、および／あるいは、その非シリコーン系セパレーターフィルムなどとして有用な二軸延伸ポリプロピレンフィルムを提供する。【解決手段】メルトフローレートが１．５ｇ／１０ｍｉｎ以上６．０ｇ／１０ｍｉｎ以下のポリプロピレン樹脂から形成された、少なくとも一方の面の表面粗さが、（ａ）中心線粗さ（Ｒａ）で０．０３〜０．１０μｍ、（ｂ）最大高さ（Ｒｍａｘ）で０．３μｍ〜１．０μｍ、であって、大きさ（長径）が５０μｍ以上のフィッシュアイの数が１００個／ｍ２以下である層を有しており、厚さが５μｍ以上６０μｍ以下であることを特徴とする、二軸延伸ポリプロピレンフィルム。【選択図】図１