JIMA (Tanning) II

 SCIENCE IN HAUSA: EPISODE 8

Bayan anyi drenching ko pickling, ana barin fatar ta kwana cikin tsimin ruwan acid din gauraye da gishiri. Wannan shine zai bawa damar sinadarin jimar zama a cikin collagen din fatar.

Abu na gama bayan awanni 24 shine zuba sinadarin jimar cikin ruwan drenching ko pickling. A wannan karatun zamu dauki pickling; zamuyi amfanin da mineral din Chromium. Bayan an zuba wannan sinadarin (yanada launin shudi) sai a dinga juya fatar cikin gangar jima (tanning drum) har na tsawon awanni 6 tareda bada tazarar awanni 2 ko 1 saboda tsimin ya shiga sosai. Wannan matakin ne ake kira da "tanning" Wanda ana yinsa domin kare fatar daga rubewa da lalacewa har abada. Bayan jimar ta dauki kayyadajjen lokaci sai abar fatar ta kwana; ana kiran fatar da "wet blue" a wannan gabar saboda launinta na shudi hade da danshi.

Bayan haka sai a ciro fatar a nannadeta domin baiwa Chromium ions damar musanya kansu da molecules din ruwa a cikin fatar; ana kiran hakan da "olation and oxolation". A kalla akan baiwa wannan tsarin kwanaki biyu kafin ya kammala. A wasu lokutan ma fatar na iya daukar watanni a matsayin wet blue saboda tasirin sinadarin jimar wajen tsarkaketa daga lalacewa. 

Yayin da akaso cigaba da jimar sai a wanke wet blue din sannan ayi "retanning" wato maimata jimar. Anan zanyi wasu bayanai kamar haka;

1- Ana iya sake jima da sinadarin tannins daga tsirrai domin samar da kamanni biyu ga fatar; siffar jimar mineral da kuma vegetable. Ana kiran irin wannan kirgin da semi-chrome leather.

2- Ana kuma iya sake jimar da Chromium wajen baiwa fatar cikakkiyar siffa da mineral. Ana Kiran irin wannan kirgin da full-chrome leather. 

3- Ana iya sake jimar da wasu abubuwa da ake kira "syntans". Wadannan syntans ne wadansu sinadarai ne da aka kirkira domin musanya tannins na tsirrai. Sunada launuka daban-daban kamar ja, ruwan dorawa da kuma ruwan kasa. Syntans suna ciko kirgi sosai ta yanda zaiyi kauri matuka. 

Anan zamu dauki na biyu wato full-chrome domin saukakawa mai karatu. Bayan an sake jima da chromium sai a sake rufe hanyoyin fitar sabon sinadarin ta hanyar "basification" da sinadarin Sodium Bicarbonate (NaHCO3). Bayan hakan sai a sake wanketa a auna nauyin; nauyi dole ya canza a wannan gabar saboda sinadaran da suka tattaru cikin fatar.

Abu na gaba mai matukar muhimmanci shine daidaita ma'aunin pH domin shigo da sinadaran alkaline. A lura da kyau cewa duk sinadaran baya dangin acidic ne, wato wadanda sukeda rauni a ma'aunin pH daga 7.0 zuwa 1.5 ko kasa da hakan. Ana amfani da sodium bicarbonate (NaHCO3) ne wajen daga pH din zuwa 5.0 ko 5.5 domin samun saukin shigar sinadarai dangin alkaline. Bayan hakan sai a wanke sannan a karasa da wadannan;

1- Rini (Dyeing): Ana iya zaban duk irin launin da akeso. Anso a sansanya kalar rini da ruwan zafi domin samun saukin shigar molecules din rinin.

2- Laushi (Fatliquor): Domin sanya kirgi lankwashewa cikin sauki, masu ilmin kimiyya ta fata sun kirkiri wannan  sinadari ne da ake narkawa da ruwan zafi domin sanya collagen din cikin kirgin suyi laushi.

3- Rufewa (Fixation) wannan shine matakin karshe a amfani da sinadarai wurin jimar fata. Fixation ana yinsa ne da Formic acid (HCOOH) domin rufe kofofin fatar/kirgin ta yanda duk abubuwan da aka sanya bazasu taba fitaba.

Bayan wannan sai a wanke sannan a shanya kirgin. Bayan ya bushe akan sanyashi cikin injina masu karawa kirgin fadi, kyau, da kuma siffa daidaitacciya. Wannan yanki ko kuma kaso daya daga cikin daruruwa kenan da ake iya sarrafa fatun da muke amfani dasu kenan a kimiyyance.

Daga cikin wadannan kirgin ne akwai;

- Shoe upper leather: takalma da angara.

- Upholstery leather: kujeru na jirage da motoci.

- Chamois leather: kirgin share gilasai (yanada siffar magogi)

- Clothing leather: tufafi, da sauransu.

Duk wani mai tambaya saiya ajiye a kasa domin samun amsoshi. Na gode da irin hakuri da juriya da kukeyi wajen bibiyar wannan ayyukan. 

© Mubarak MS Jigirya

    07/08/2021