【発明の詳細な説明】[Detailed description of the invention]
本発明は蓄電池用、特に密封型蓄電池用の隔離
板に関する。
従来密封型蓄電池用の電解液保持体として使用
する隔離板は、吸液率を大きくし、最大孔径を小
さくするために繊維径が2μ以下のガラス繊維を
主体とし、これに抗張力を与えるべく水度350
c.c.以下のフイブリル状合成繊維10wt％以下を混合
したものが知られている。かかる隔離板を備えた
密封型蓄電池は例えばVTR等のポータブル機器
の電源として使用される場合、放電して容量減少
しても直ちに充電されることなく長時間そのまま
の状態で放置されることが多く、その後充電され
ても容量が初期状態迄回復せず、隔離板の充電回
復性が悪いという不都合を有する。
本発明はかかる不都合を解消し、充電回復性に
優れると共に、吸液率、最大孔径及び抗張力が前
記従来のものに劣らない蓄電池用隔離板を提供す
るもので、繊維径２〜9μのガラス繊維50〜80wt
％、繊維径2μ未満のガラス繊維10〜45wt％及び
水度350c.c.以下のフイブリル状合成繊維10wt％
以下を混合して成ることを特徴とする。
以下本発明を対照例及び従来例と比較しながら
詳述する。
各種繊維径及び配合量のガラス繊維を主体と
し、残部を水度350c.c.以下のフイブリル状合成
繊維10wt％以下で構成した板状の蓄電池用隔離板
を形成し、充電回復性を始め、吸液率、抗張力及
び最大孔径に付き試験を試みた。その結果は表−
１に示す通りであつた。尚、表−１における隔離
板の組成について例を挙げて説明する。
本発明例の資料番号Ａの場合は
太さ2μのガラス繊維の配合が50wt％
太さ1μのガラス繊維の配合が45wt％
水度350c.c.のフイブリル状合成繊維の配合が
5wt％
である。
また、従来例の資料番号Ｋの場合は
太さ1μのガラス繊維の配合が95wt％
水度350c.c.のフイブリル状合成繊維の配合が
5wt％
である。
また、表−１におけるフイブリル状合成繊維の
水度（c.c.）とは JIS Ｐ 8121で規定されたカ
ナダ標準形に基づく水度（単位c.c.）である。
The present invention relates to a separator for storage batteries, in particular for sealed storage batteries. Conventionally, separators used as electrolyte holders for sealed storage batteries are mainly made of glass fibers with a fiber diameter of 2μ or less in order to increase the liquid absorption rate and reduce the maximum pore size, and are coated with water to give them tensile strength. degree 350
Mixtures containing 10 wt % or less of fibrillar synthetic fibers of cc or less are known. When a sealed storage battery equipped with such a separator is used as a power source for a portable device such as a VTR, it is often left as it is for a long time without being immediately charged, even if it discharges and its capacity decreases. , even if it is subsequently charged, the capacity does not recover to the initial state, and the separator has a disadvantage that the charge recovery property is poor. The present invention eliminates such disadvantages, and provides a separator for storage batteries that has excellent charge recovery properties and is comparable in liquid absorption rate, maximum pore diameter, and tensile strength to those of the conventional ones. 50~ 80wt
%, 10 to 45 wt% glass fibers with a fiber diameter of less than 2μ, and 10 wt % fibrillar synthetic fibers with a water content of 350 c.c. or less
It is characterized by being composed of a mixture of the following: The present invention will be described in detail below while comparing it with a control example and a conventional example. We form a plate-shaped storage battery separator mainly composed of glass fibers of various fiber diameters and blending amounts, and the remainder is 10 wt % or less of fibrillar synthetic fibers with a water content of 350 c.c. or less. , liquid absorption rate, tensile strength and maximum pore diameter were tested. The results are shown in the table-
It was as shown in 1. The composition of the separator in Table 1 will be explained by giving an example. In the case of document number A of the present invention example, the blend of glass fiber with a thickness of 2 μ is 50 wt%, the blend of glass fiber with a thickness of 1 μ is 45 wt%, the blend of fibrillar synthetic fiber with a water content of 350 c.c.
It is 5wt%. In addition, in the case of the conventional example, document number K, the blend of glass fibers with a thickness of 1μ is 95 wt%, and the blend of fibrillar synthetic fibers with a water content of 350 c.c.
It is 5wt%. Furthermore, the water content (cc) of the fibrillar synthetic fiber in Table 1 is the water content (in cc) based on the Canadian standard form specified in JIS P 8121.
【表】
この試験から明らかなように繊維径2μ以上の
ガラス繊維を50wt％以上含むことが充電回復性向
上のために必要なことが確認された（資料番号Ａ
〜Ｅ、Ｆ、Ｈ、Ｊ）。即ち全てのガラス繊維の繊
維径が2μ未満の従来品（資料番号Ｋ）及び繊維
径2μ以上のガラス繊維を50wt％以上含まないもの
（資料番号Ｇ、Ｉ）は充電回復性の向上が認めら
れなかつた。
又、充電回復性が向上する場合でも、繊維径
2μ以上のガラス繊維を80wt％を超えて含む場合に
は吸液率が悪く、最大孔径も大きくなり電池性態
を悪化させ（資料番号Ｆ、Ｈ）、繊維径が9μを超
えるガラス繊維を50wt％以上含む場合には極端に
最大孔径が大きくなり鉛粉の透過がしやすくなり
電池寿命が低下する（資料番号Ｊ）。
従つて繊維径２〜9μのガラス繊維を50〜80wt％
含むことが、充電回復性を向上させると共に吸液
率及び最大孔径を従来のものと同様に優れたもの
とするために必要である。
又、繊維径2μ未満のガラス繊維は10〜45wt％の
範囲とすることが必要である（資料番号Ａ〜Ｅ）。
これは、10wt％未満では吸液率が少なく、最大孔
径が大きくなり（資料番号Ｆ、Ｈ）、45wt％を越
えると充電回復性が低下するからである（資料番
号Ｇ、Ｉ）。
以下本発明の実施例を説明する。
実施例 １
繊維の長さ0.5〜20mmで繊維径3μのガラス繊維
50wt％、繊維の長さ0.5〜20mmで繊維径0.7μのガラ
ス繊維45wt％及びアクリル繊維をビーターで叩解
し、水度300c.c.のフイブリル状としたもの5wt％
を混合し、抄造装置を使用して板状に抄紙し、脱
水、プレスを行い厚さ１mm、秤量180ｇ／m2の蓄
電池用隔離板を得た。
実施例 ２
繊維の長さ0.5〜20mmで繊維径3μのガラス繊維
65wt％、繊維の長さ0.5〜20mmで繊維径0.7μのガラ
ス繊維30wt％、アクリル繊維をビーターで叩解
し、水度300c.c.のフイブリル状としたもの5wt％
を混合し、抄造装置を使用して板状に抄紙し、脱
水、プレスを行い厚さ１mm、秤量180ｇ／m2の蓄
電池用隔離板を得た。実施例１、２によつて得ら
れた蓄電池用隔離板は、共に充電回復性が100％
と優れ、しかも従来のものと同様に吸液率、抗張
力にも優れ、且つ最大孔径の小さなものであつ
た。
このように本発明による蓄電池用隔離板は、繊
維径２〜9μのガラス繊維50〜80wt％、繊維径2μ未
満のガラス繊維10〜45wt％及び水度350c.c.以下
のフイブリル状合成繊維10wt％以下の混合物から
成るので、優れた吸液率、抗張力を有し、且つ最
大孔径が小さいことに加え、優れた充電回復性を
併せ有する効果をもたらす。[Table] As is clear from this test, it was confirmed that containing 50 wt % or more of glass fibers with a fiber diameter of 2 μ or more is necessary to improve charge recovery performance (Document No. A
~E, F, H, J). In other words, conventional products (Document No. K) in which all glass fibers have a fiber diameter of less than 2μ and products that do not contain 50 wt % or more of glass fibers with a fiber diameter of 2μ or more (Document No. G, I) have been found to have improved charge recovery performance. I couldn't help it. Furthermore, even if charge recovery is improved, the fiber diameter
If it contains more than 80 wt % of glass fibers with a diameter of 2μ or more, the liquid absorption rate will be poor and the maximum pore size will increase, deteriorating the battery properties (Document No. F, H). If it contains more than 50 wt %, the maximum pore diameter becomes extremely large, making it easier for lead powder to permeate and shortening the battery life (Document No. J). Therefore, 50 to 80 wt % of glass fiber with a fiber diameter of 2 to 9μ is used.
This inclusion is necessary in order to improve the charge recovery property and to make the liquid absorption rate and maximum pore diameter as excellent as those of the conventional ones. Further, it is necessary that the glass fibers having a fiber diameter of less than 2 μm be in the range of 10 to 45 wt % (Document numbers A to E).
This is because when the content is less than 10 wt %, the liquid absorption rate is low and the maximum pore diameter becomes large (Document No. F, H), and when it exceeds 45 wt %, the charge recovery property decreases (Document No. G, I). Examples of the present invention will be described below. Example 1 Glass fiber with a fiber length of 0.5 to 20 mm and a fiber diameter of 3μ
50 wt %, 45 wt % glass fibers with a fiber length of 0.5 to 20 mm and a fiber diameter of 0.7 μ, and 5 wt % of acrylic fibers beaten with a beater to form fibrils with a water content of 300 c.c.
The mixture was mixed, made into a plate using a paper making machine, dehydrated and pressed to obtain a separator for a storage battery with a thickness of 1 mm and a basis weight of 180 g/m 2 . Example 2 Glass fiber with a fiber length of 0.5 to 20 mm and a fiber diameter of 3μ
65 wt %, 30 wt % glass fiber with a fiber length of 0.5 to 20 mm and a fiber diameter of 0.7μ, 5 wt % acrylic fiber beaten with a beater and made into a fibril with a water content of 300 c.c.
The mixture was mixed, made into a plate using a paper making machine, dehydrated and pressed to obtain a separator for a storage battery with a thickness of 1 mm and a basis weight of 180 g/m 2 . The storage battery separators obtained in Examples 1 and 2 both had charge recovery properties of 100%.
Furthermore, it had excellent liquid absorption and tensile strength as well as the conventional ones, and had a small maximum pore diameter. As described above, the separator for storage batteries according to the present invention is composed of 50 to 80 wt % glass fibers with a fiber diameter of 2 to 9 μm, 10 to 45 wt % glass fibers with a fiber diameter of less than 2 μm, and a fibrillar composite with a water content of 350 c.c. or less. Since it is composed of a mixture of 10 wt % or less of fibers, it has excellent liquid absorption and tensile strength, and has a small maximum pore diameter, as well as excellent charge recovery properties.