Presentation on theme: "Micro Fibre Dyeing By Roy Gordon. Dyeing 1 Key Issues The 2 most important factors in dyeing polyester microfibres. Build-up properties. Washfastness."— Presentation transcript:
Micro Fibre Dyeing By Roy Gordon
Dyeing 1 Key Issues The 2 most important factors in dyeing polyester microfibres. Build-up properties. Washfastness. BUILD-UP WASH FASTNESS 1Depth of shade X 1/ fibre dpf. Finer fibres need more dye. 2Dye buildup properties can vary with finer fibres. DYE & AUXILIARY SELECTION 1High dye applications needed. 2Washfastness relates to surface dye. Microfibres have very high surface area. DYE & AUXILIARY SELECTION Problems CausesRemedies
Various factors POTENTIAL PROBLEMS CAUSESREMEDIES Dye uptake at lower temperatures. Commence dyeing at lower start temperatures. LEVEL DYEINGFaster dye uptake rate. Use slower rate of temperature rise up to top temperature. Residues from preparation steps. Use of auxiliaries to level and protect from residues. Poor penetration of high twist yarns on high density fabric. Compatible dye combinations. CREASING &Poor relaxed shrinkage in preparation. Control over the preparation process. CROWS FEETRapid temperature rise at critical heating and cooling phases. Use slower rate of temperature rise up to top temperature. Use of anticrease auxiliaries. LIGHTFASTNESSHigh surface area exposed to light. Careful selection of Dyes. Use of UV absorbers to reduce fading. Microfibre mixed with conventional fibres. Dye selection DYE COVERAGEFlat and textured yarns combined. Dyeing process to improve leveling. Filaments of varying cross section. Use of auxiliaries to improve dyeing. ABRASION Inadequate preparation leaving spin finish, oils, oligomer and WR residues. Good quality preparation. MARKSIncorrect machine type. Correct machine type usage. Dyeing lubricant to reduce abrasion. Dyeing 2
Microfibre Dyeing Process: Takes account of… Rapid strike and exhaustion on Microfibres. Greater rate and extent of shrinkage. Lower temperature exhaustion and shrinkage, relative to conventional fibres. Dyeing 3. Process 50 o C Load Auxiliaries and pump. Load buffer and dyes. Raise temperature - Rate 1. Raise temperature - Rate 2. Hold at Top Temperature. Cool at Rate 1. Hot 90 o C Use Rate’s 1 & 2. RC or o C. Rinse Drop cold, < 55 o C. Temp o C 70 o C 50 o C 130 o C x 45’ 70 o C 2 o /min 1 o /min 2 o /min 3 o /min 2 o /min 1 o /min ConventionalMicrofibre Rate of rise depends on the machine liquor interchange and dye type. Tip : Plait down fabric evenly
NEARGAL HP-MF Dispersant and levelling agent. New Levels without retarding, so perfect for micofibres. Oligomer dispersant, so minimal WR problems. Proven in yarn package dyeing. ( See later presentation.) LUBRIFIL LAF Emulsifier, anticrease and compatibiliser. Emulsifies de dusting agents and residual oils. Enhances Heat Setting efficiency. Reduces creasing and abrasion. A problem solver. Auxiliaries 1 Microfibre Dyeing Auxiliaries: Must take account of.... Fibre variations in dpf, cross section, texturising and polymer type. Variations in dye types, helping to balance strike and migration. The inevitable carry-over of residues and contamination into the dye bath. Dyeing 4.1
NAISTAT 1350 Oil scavenger, anticrease, lubricant, finishing agent. High affinity for polyester allows displacement of residual oils from polyester. Powerful lubricity to reduce abrasion and creases. Durable finish; antistat, soil release, soft and hydrophilic. NEARCHEL TMC High Temperature stable sequesterant. Suitable for preparation and bleaching. Disaggregates dyes for penetration. Powerful metal binding, even at high temperatures. MATEXIL LN-RD High activity levelling agent. For light or problem shades. Success over Lyogen DMF, Levenol, Sunsalt LM7. Auxiliaries 2 Dyeing 4.2
Auxiliary Solutions Dyeing 4.3 Problems Rapid dye uptake rate. (Actually ~ x 4) Residues from spinning and preparation. Poor penetration. Crease problems. Varying filament dye uptake. Auxiliary Solutions Levelling Auxiliary NEARGAL HP-MF New NEARGAL SD-PE Emulsifier and Scavenger LUBRIFIL LAF NAISTAT 1350 Oligomer DispersantNEARGAL HP-MF New Penetration aidLUBRIFIL LAF NAISTAT 1350 Dye DispersantNEARGAL DN Anticrease agentLUBRIFIL LAF NAISTAT 1350 Levelling AuxiliaryNEARGAL SD-PE NEARGAL HP-MF New
Auxiliaries 3 Some Recipes Basic (For blends or 100% polyester.) NEARGAL DN 0.5 – 1 g/l LUBRIFIL LAF 2 g/l NEARCHEL TMC 0.5 g/l NEARGAL SD-PE1 g/l Problem shades (For 100% polyester.) NEARGAL DN 0.5 – 1 g/l NEARGAL HP-MF New 1.5 g/l LUBRIFIL LAF 2 g/l NEARCHEL TMC 0.5 g/l Problem fabrics (For 100% polyester.) NEARGAL DN 0.5 – 1 g/l NAISTAT g/l NEARCHEL TMC 0.5 g/l NEARGAL SD-PE 1.5 g/l Problem fabrics and shades (For 100% polyester.) NEARGAL DN g/l NEARGAL HP-MF New 1.5 g/l NAISTAT g/l NEARCHEL TMC 0.5 g/l Dyeing 4.4 Tip : Use high fabric rope speeds 260 m/m)
Microfibre Dye Selection: Must take account of.... Compatibility and suitability for the application. The wash fastness requirements on medium to heavy shades. The rapid buildup and levelling problems on fine fibres. The mixture of fibre type in many microfibres. Dyeing 5.1 Dyes : General Pales shades B class dyes give :… - the best levelness and coverage. - compatibility in trichromatic shades. Medium / Heavy C class dyes give :… - good levelness and coverage. - good general compatibility. - all round fastness properties. All dye variations or incompatibilities are exaggerated when dyeing Microfibres.
Dyeing 5.2 Buildup Colour Build-up “rule of thumb” : fine filaments dye light, course filaments dye dark. Fothergills equation. (in 1944) C1 W2 C2 W1 C1 & C2 = % dye applied. W1 & W2 = DPF of fibrils. = This equation does not take account of delustering agents, fibre cross section, orientation or crystallinity, texturing, or finishing agents.
Dyeing 5.3 Fastness Light Fastness “rule of thumb” : reductions of 0.5 to 1.5 point for Micro vs regular fibre. The high surface area exposes more dye to UV light, thus reducing light fastness. Testing : Xenotest vs wool standards. ISO 105 B02International BS 1006 B02British DIN 54004German This may restrict dye selection, especially for sportswear. Trevira 5 Trevira 4-5 ?? UV absorbers can be added to the disperse dyebath for the highest standards.
Dyeing 5.4 Fastness Wash Fastness : a constant problem. THE CAUSES ? High surface area, means a greater amount of surface dye present. Weight Reduced fibres have oligomer residues that can reduce fastness. Weight Reduced fibres have a rough surface that can act as a store for oligomer and surface dye. WR on delusted fibres leave pores, that act as reservoirs of surface dye. Spandex Microfibre may have silicone residues that reduce fastness. THE REMEDIES ? A very effective wash after Weight Reduction is essential. A very effective high temperature Reduction Clear and wash is essential. A double Reduction Clear may be required. Use of wetting, penetrating and dispersing auxiliaries in both WR wash and RC.
NEARGAL DN High performance dispersing agent for Oligomer and Dye. Proven performance as a machine cleaner and dispersant. NEARCLEAR VL Powerful wetter, dispersant, emulsifier and detergent. Proven performance in Reduction Clear Lifts surface dye and disperses residues. Reduction 92 0 C x 20’NEARGAL DN0.5 g/l NEARCLEAR VL 0.5 g/l (& when ready to give up, add..) NEARPON KR0.3 g/l The WR process creates a rough semi-porous fibre surface, which can trap large amounts of surface dye. The high surface area alone creates wash fastness problems for microfibres.
Dyeing 5.5 Dyes : The best dyes to use on polyester are : Those with Identical Exhaustion Rates Easy clearing dyes :eg Diester dyes Azo-Thiophene dyes
Dyeing 6 Conjugates : With certain types of conjugate filament…. The compliment or core polymer fibrils may “grin” through the shade, creating a streaky, speckled and uneven look. This mainly occurs where : -the compliment fibril is only shocked (by swelling or physical cracking) rather than dissolving. -the complimentary fibril is a major part. -the conjugate microfibre is a major component of the fabric. -the nylon component is not structurally covered by polyester. Regain solidity of shade by overdyeing with acid dyes. NEARGAL LS-PA with acid dyes.
Example 1 Light Weight Silk Pre-steam if possible. Pad NAISTAT 2% 120 o C then Set at 160 o C x 30”. Wash and scour with NEARFIL FAC0.3 g/l NEARPON KR1 g/l NEARCHEL TMC0.5 g/l Rinse, and refill. Weight Reduce to calculated %WR. Use accelerant.~ 1 g/l 90 C, then 95C with NEARCLEAR VL0.5 g/l Hot rinse again until neutral. Dye withNEARGAL DN1 g/l NEARCHEL TMC0.5 g/l NEARGAL SD-PElevelling problems. RC as for WR Washing. Finish by 60% PU NEARFINISH M8820 g/l 120 o C then Set at 160 o C x 40”. Heat Set improver Oil Scorch Protector Silicone & Set oil Scour system Dispersing and Washing system. Dispersing, Levelling and Sequestering. Bodied Finish Softener Desize / Scour & Relax Pre Heat Set Weight Reduce Dye Finish with Dry Mild Set Simple Process Wash off RC
Example 2 Sports Wear - Spandex Wash, scour and relax with NEARFIL FAC0.2 g/l NEARPON KR1 g/l NEARCHEL TMC0.5 g/l LUBRIFIL LAF1.5 g/l Rinse, and refill. Pad NAISTAT 2% 120 o C then Set at 195 o C x 1’. Dye withNEARGAL DN1 g/l NEARCHEL TMC0.5 g/l NEARGAL SD-PEleveling problems. 90 C, then 90 C with NEARCLEAR VL0.5 g/l Hot rinse again Finish by 80 o C NAISTAT 13504% owf 120 o C then Set at 160 o C x 40’. Heat Set improver Oil Scorch Protector Silicone & Set oil Scour system Dispersing and Washing system. Dispersing, Levelling and Sequestering. Soft hydrophIlic, soil release antistatic finish. Desize / Scour & Relax Pre Heat Set Dye Finish with Dry Mild Set Normal Process RC
The Products The Process The Advantage NEARFIL FACDeaerationNo foam wetting. LUBRIFIL LAF Heat Setting Efficient & Antiscorch Scour & Dye Scour-Dye & Anticrease NEARPON KR Scour Efficient Cleaning NEARCHEL TMCScourRemoval of soaps DyeingDisaggregator NEARCAND LT 75Setting & FinishReduce scorching BleachWhite nylon NEARGAL DN DyeingDispersant and cleaner. NEARGAL SD-PEDyeingDispersant & Leveller NAISTAT 1350 Heat SettingEfficient & Antiscorch FinishingHydrophilic, soil release NEARFINISH CF 511 FinishingHydrophilic, elastic NEARSOPHT BF100FinishingFull body cationic. NEARFINISH M88FinishingBodied effect.