縮水是紡織品(pin)在一(yi)定狀態經過(guo)洗滌、脫水、干燥等(deng)過(guo)程(cheng)發生長(chang)度或寬度變化的一(yi)種(zhong)現象。 縮水程(cheng)度涉及不(bu)同(tong)種(zhong)類的纖維、織物的結構、織物加工時所受之不(bu)同(tong)外力(li)作用(yong)等(deng)等(deng)，有著(zhu)不(bu)同(tong)的的表現。

1、纖(xian)維在(zai)紡紗(sha)(sha)時，或(huo)紗(sha)(sha)線在(zai)織(zhi)造(zao)及染整時，織(zhi)物(wu)中(zhong)之(zhi)紗(sha)(sha)線纖(xian)維受外力(li)作用而伸(shen)長(chang)或(huo)變形，同時紗(sha)(sha)線纖(xian)維及織(zhi)物(wu)結構產生(sheng)內應力(li)，在(zai)靜態(tai)(tai)(tai)(tai)干(gan)松(song)弛(chi)(chi)狀態(tai)(tai)(tai)(tai)，或(huo)靜態(tai)(tai)(tai)(tai)濕松(song)弛(chi)(chi)狀態(tai)(tai)(tai)(tai)，又或(huo)在(zai)動態(tai)(tai)(tai)(tai)濕松(song)弛(chi)(chi)狀態(tai)(tai)(tai)(tai)、全松(song)弛(chi)(chi)狀態(tai)(tai)(tai)(tai)下，不同程度內應力(li)之(zhi)釋放，使(shi)紗(sha)(sha)線纖(xian)維及織(zhi)物(wu)回(hui)復至初始狀態(tai)(tai)(tai)(tai)。

2、不同(tong)的纖(xian)(xian)維(wei)及其(qi)(qi)(qi)織物，其(qi)(qi)(qi)縮水程(cheng)(cheng)度都不同(tong)，主要取決(jue)于其(qi)(qi)(qi)纖(xian)(xian)維(wei)的特(te)性(xing)-親水性(xing)纖(xian)(xian)維(wei)的縮水程(cheng)(cheng)度較大，例如棉、麻、粘(zhan)膠等(deng)纖(xian)(xian)維(wei)；而疏(shu)水性(xing)纖(xian)(xian)維(wei)的縮水程(cheng)(cheng)度較少(shao)，例如合成(cheng)纖(xian)(xian)維(wei)等(deng)。

3、纖(xian)維(wei)(wei)在(zai)潤濕狀態時，因浸液的(de)作用下產生膨化，令纖(xian)維(wei)(wei)直徑變大，如(ru)在(zai)織(zhi)物上(shang)，迫(po)使織(zhi)物之交織(zhi)點之纖(xian)維(wei)(wei)曲率半徑增(zeng)加(jia)，引致(zhi)織(zhi)物長度(du)(du)縮(suo)短(duan)。例如(ru)棉纖(xian)維(wei)(wei)在(zai)水的(de)作用下膨化，橫截面積增(zeng)大40~50%，長度(du)(du)增(zeng)加(jia)1~2%，而合成纖(xian)維(wei)(wei)則對熱收縮(suo)，如(ru)沸(fei)水收縮(suo)等，一般5%左右。

4、紡(fang)織纖(xian)(xian)維(wei)受熱(re)(re)條(tiao)件(jian)下，纖(xian)(xian)維(wei)的(de)(de)(de)(de)形態及尺寸發生變化及收(shou)(shou)縮(suo)，降溫后(hou)亦(yi)不(bu)能(neng)回復到初始狀態，稱(cheng)為(wei)(wei)纖(xian)(xian)維(wei)熱(re)(re)收(shou)(shou)縮(suo)。而熱(re)(re)收(shou)(shou)縮(suo)前與熱(re)(re)收(shou)(shou)縮(suo)后(hou)的(de)(de)(de)(de)長度(du)百(bai)分(fen)比稱(cheng)為(wei)(wei)熱(re)(re)收(shou)(shou)縮(suo)率(lv)，一般以沸水收(shou)(shou)縮(suo)測(ce)試，在(zai)100℃沸水中(zhong)，纖(xian)(xian)維(wei)長度(du)收(shou)(shou)縮(suo)的(de)(de)(de)(de)百(bai)分(fen)率(lv)作表(biao)示；亦(yi)有(you)用熱(re)(re)空(kong)(kong)氣(qi)(qi)方式，在(zai)超過100℃的(de)(de)(de)(de)熱(re)(re)空(kong)(kong)氣(qi)(qi)中(zhong)測(ce)其(qi)(qi)收(shou)(shou)縮(suo)的(de)(de)(de)(de)百(bai)分(fen)率(lv)，亦(yi)有(you)用蒸氣(qi)(qi)方式，在(zai)超過100℃的(de)(de)(de)(de)蒸氣(qi)(qi)中(zhong)測(ce)其(qi)(qi)收(shou)(shou)縮(suo)的(de)(de)(de)(de)百(bai)分(fen)率(lv)。纖(xian)(xian)維(wei)因內部結構(gou)及受熱(re)(re)溫度(du)、時間等不(bu)同(tong)(tong)條(tiao)件(jian)下表(biao)現亦(yi)不(bu)同(tong)(tong)，例如加(jia)工滌(di)綸(lun)短纖(xian)(xian)的(de)(de)(de)(de)沸水收(shou)(shou)縮(suo)率(lv)為(wei)(wei)1%，維(wei)綸(lun)沸水收(shou)(shou)縮(suo)率(lv)為(wei)(wei)5%，氯(lv)綸(lun)熱(re)(re)空(kong)(kong)氣(qi)(qi)收(shou)(shou)縮(suo)率(lv)為(wei)(wei)50% 。纖(xian)(xian)維(wei)在(zai)紡(fang)織加(jia)工及其(qi)(qi)織物的(de)(de)(de)(de)尺寸穩定性(xing)有(you)著密切的(de)(de)(de)(de)關系，為(wei)(wei)后(hou)工序之(zhi)設計提供一些依據(ju)。