METHOD FOR MANUFACTURING AIR FILTER MEDIUM

• Main Authors: YAMAMOTO SEIGO, INUI KUNIHIKO, YOSHIOKA YUKINA
• Format: Patent
• Language: English; Japanese
• Published: 08.10.2020
• 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; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; 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 method for manufacturing an air filter medium which can improve homogeneity of a pressure loss.SOLUTION: A method for manufacturing an air filter medium having a porous film of a fluorine resin includes a step of increasing a stretch length speed (m/min) in a predetermined stretch direction during stretching of the fluorine resin sheet in the predetermined stretch direction. Preferably, during the stretching of the fluorine resin sheet in the predetermined stretch direction, a change in the stretch length speed (m/min) in the predetermined stretch direction is continuous. More preferably, in the stretching of the fluorine resin sheet in the predetermined stretch direction, the stretching is performed in a state where the stretch length speed (m/min) in the predetermined stretch direction is lowered after the stretch length speed (m/min) in the predetermined stretch direction is increased and the sheet is stretched and before the stretching in the predetermined stretch direction is finished.SELECTED DRAWING: Figure 4 【課題】圧力損失の均質性を向上させることが可能なエアフィルタ濾材の製造方法を提供する。【解決手段】フッ素樹脂の多孔膜を有するエアフィルタ濾材の製造方法であって、フッ素樹脂シートを所定延伸方向に延伸する最中に、所定延伸方向における延伸長さ速度（ｍ／ｍｉｎ）を上げる工程を備えており、好ましくは、フッ素樹脂シートを所定延伸方向に延伸する最中において、所定延伸方向における延伸長さ速度（ｍ／ｍｉｎ）の変化が連続的であり、さらに好ましくは、フッ素樹脂シートの所定延伸方向への延伸では、所定延伸方向における延伸長さ速度（ｍ／ｍｉｎ）を上げて延伸した後であって、所定延伸方向の延伸を終える前に、所定延伸方向における延伸長さ速度（ｍ／ｍｉｎ）を下げた状態で延伸を行う。【選択図】図４