Operation Bleaching Process of Textile Material Textile Finishing Technology SMKN 1 KATAPANG KABUPATEN BANDUNG Kelas X Semester 2

Bleaching Process Bleaching is process to remove the coloured impurities from textile fibers so that obtained a white and good materials.Either with an oxidizing or reducing agent Teknologi dan Rekayasa

The kinds of agents bleaching: 1. Oxidator agent of bleaching Oxidator agent of bleaching have two classification : that is concidering chlorine and which do not contain chlorine Teknologi dan Rekayasa

Oxidator agents of bleaching do not containing chlorine consist of : - Hidrogen peroxide - Sodium Peroxide - Sodium Perborat - Potassium of bikhromat - Potassium of permanganat Teknologi dan Rekayasa

Oxidator agent of bleaching containing of chlorine consist of: - Caporit - Sodium hipoclorit - Natrium chlorit Teknologi dan Rekayasa

2.Reduktor agents of bleaching consist of : - Sulphur dioxide - Sodium sulfit - Sodium Bisulfit - Sodium hidrosulfit Teknologi dan Rekayasa

Charasterictic of Bleaching Treatment 1. Caporit Caporit is salt double from CaCl2 and of Ca(OCl)2, so that was repreasented by the formula CaOCl2. Caporit in form of bleaching powder is strong oksidator and is generally used for the whitening of cotton. Caporit in commercial containing about 30-60% clor active. When the first caporit react in water to become its salt,then hidrolysis liberates hipochlorit the unstableness and easy to ravelled to become hidrogen chlorida and oxygen . Teknologi dan Rekayasa

Ca(OCl)2 + 2H2O Ca(OH)2+ 2HOCl HOCl HCl + On 2CaOCl2 CaCl2 + Ca(Ocl)2 Ca(OCl)2 + 2H2O Ca(OH)2+ 2HOCl HOCl HCl + On Reaction of above chemistry of more important mean in bleaching with kaporit. During process of bleaching, caporit also liberate gaseous of klor which a part some to be absorp its material . Gaseous of klor this can result damage of fibre so that strength of fibre descend. For avoid to be needed by removing klor process with sodium bisulfit,sodium sulfit, sodium hjdrosulfit. Teknologi dan Rekayasa

Factors effect decomposition of salt of hipochlorit 1) Effect of pH 2) Effect of carbondioksida 3) Effect of oxide and metal Teknologi dan Rekayasa

Procedur operation of bleaching process with caporit used exhaustion methode Recipe Bleaching process Caporit : 1-2-3-4-5 gr/l Na2CO3 : 4- 5 g/l Wetting agent : 1 ml/l Temperature : at room temperature Time : 60 minute Liquor ratio : 1 :30 Acidity process HCl : 3 ml/l Time : 15 minute Liquor ratio : 1 : 30 Removing Klor process Na2S2O4 : 3 g/l Temperature : 70oC Teknologi dan Rekayasa

Procedure Operation - Good materials and chemical agent to weigh as according to calculation of recipe - Water, kaporit,Na2CO3 and wetting agent prepared as according to liquor ratio at recipe - Fabric done at solution process with room temperature of , then stir to flatten during 60 minute - Then fabric rinsed afterwards acidity process during 15 minute - Afterwards fabric cleaned by hot water;then cleaned to be chill water - Removing clor process during 15 minute, at temperature 50oC - Materials cleaned and dried later;then perceive result of him cover white degree test of fabric. Teknologi dan Rekayasa

Schema Process of Bleaching Cotton with Capori used Exhaustion Methode Acidity process Removing Klor 70oC 0 60 0 15 0 15 Time (minute) Schema Process of Bleaching Cotton with Capori used Exhaustion Methode Rinsed by water Rinsed by hot water and chill water Washing TemperatureoC 30oC Caporit Na2CO3 Wetting agent HCl Na2S2O4 Teknologi dan Rekayasa

2.Sodium Hipoklorit Sodium hipokloritof is bleaching agent having oxidation energy which is was highest to be compared the other bleaching agent witth redox-potensial among 1400 mv - 1550 mv. Sodium hipoclotite generally contain 15-18 % the available clor very alkalis. This chemical agent is relative cheaper and in its use can be combined with bleaching agent and also can be used at combined process (continue) by scouring at high temperature with kier boiling. Insuffiency or loss of usage of this agent in storage unstabilized and decomposition (in reduction) tend liberate gas of klor in consequence of redox-potensial of agents. salt of sodium hipokhlorit ravelled by strong acid become acid of hipokhlorit or yield chlorine gas depended from to the number of acids which is ekuivalen, Teknologi dan Rekayasa

Factors influencing decomposition of salt of sodium hipokhlorit Reaction : NaOCl + HCl NaCl + HOCl NaOCl + 2HCl NaCl + Cl2 + H2O Factors influencing decomposition of salt of sodium hipokhlorit 1) Influence of pH 2) Influence of oxide and metal of Teknologi dan Rekayasa

4. Hidrogen Peroxide In general peroxide bleaching which was often used in textile industry are commercialized peroxide hydrogen was also recognized by perhidrol. In commerce of peroxide hydrogen in the form of condensation which the was concentration of gyrating 35 - 50% ( 130 - 200 volume) and stabilized with acid. Nature of dissolve easy peroxide hydrogen in water at various comparison, if heated easy to ravelled to discharge oxygen gas so that very used effective for bleaching. Teknologi dan Rekayasa

Factors influencing decomposition of H2O2 1) Influence of pH H2O2 → H2O + On Factors influencing decomposition of H2O2 1) Influence of pH 2) Influence of temperature 3) Influence of stabilizer 4) Influence of metal oxide or metal. Teknologi dan Rekayasa

Optical brightenning Optical brightenning agent is agent to add brightness of materials because enlarging reflection of sun light, so that fabric look white and more light. Reflection of light happened because optical brightenning agent have the character of fluoresen. Teknologi dan Rekayasa

1. Derivat-derivat of flavonat acid,used for natural fibre Optical brightenning process can be done after bleaching , but earning also together simultan bleaching or finishing ,depended of optic to be used. Optical brightenning agent can be classified to become 2 group,that is: 1. Derivat-derivat of flavonat acid,used for natural fibre 2. Heterociklik used for synthetic fibre . Teknologi dan Rekayasa

Procedur operation of optical brightenning process with exhaustion methode Recipe Optical Brightenning Process -Uvitex : 3 % of solution -NaCl : 4 g/l -Time : 50 minute -Temperature : 80 – 90oC - Liquor ratio : 1 : 30 Teknologi dan Rekayasa

Procedure Operation - Materials and chemical agents to weigh as according to calculation of recipe - Water and chemical agents prepared as according to liquor ratio at recipe - Fabric done at solution process with temperature 80o - 90oC, then stir to flatten during 50 minute - Then fabric cleaned by hot and chill water - Materials which have cleaned to be to dried ;then weigh and perceive the brightness of fabric Teknologi dan Rekayasa

Schema Process Uvitex NaCl SuhuoC 90oC OBA Process 30oC Rinsed by Hot water And chill water OBA Process 0 15 65 Time (minute) Schema Process Optical Brightenning Process Of Tetoron Cotton Teknologi dan Rekayasa