In cellulosic and man-made fiber finishing, softness, drape, low yellowing, and strength retention are hard to achieve together. General dimethyl silicone gives basic lubrication but lacks polar amino groups, so retention on cotton, viscose, and lyocell is limited and hand decays after washing. High-viscosity high-amine oils feel soft but emulsify slowly, penetrate poorly on thin cloth, and may stick on napping/sanding rolls. Resin finishing often needs plasticizing co-additives for handfeel; if the soft oil is incompatible with the resin system, yellowing, demulsification, or rigid refrosting may occur. With woven, knitted, nonwoven, napping, and sanding lines demanding "smooth-soft, drapable, low-yellowing, elastic, strength-improving", finding a "diamino, medium-low viscosity, easily microemulsifiable, resin-plasticizing compatible" base oil has become a key formulation issue. Addressing this, Anhui IOTA Silicone Oil Co., Ltd. officially launches ECOSOFT IOTA C803. Characterized by "medium-low viscosity diamino-functionalized polydimethylsiloxane; typical appearance clear to slightly hazy, no suspended matter or sediment, slight amine odor; viscosity about 300 mPa·s at 25℃, flash point 104℃, active content 100%, nitrogen 4200 ppm N (about 0.33% amine content)", backed by "dual-amino multi-point anchoring + medium-low viscosity spreading + microemulsion compatibility + resin plasticizing compounding", it serves as the "soft-drape choice" for cellulosic/man-made softening and lubrication, achieving the leap from "single-amino thick-greasy poor-penetration" to "diamino medium-low-viscosity smooth-soft drape". System Positioning: Dual-Amino Medium-Low Viscosity Base vs. Single-Amino/High-Viscosity Soft Oils C803 belongs to diamino-functional polydimethylsiloxane crude oil, distinct from single-amino soft oils and high-viscosity high-amine products. The diamino structure provides two amino interaction sites along the chain for stronger hydrogen bonding and dipole orientation on cellulose hydroxyls and man-made fiber polar surfaces; medium-low viscosity around 300 mPa·s balances emulsification, dispersion, and yarn-gap penetration, avoiding slow spreading and local oil buildup of high-viscosity oils in microemulsion and napping. It works both as a base for amino silicone emulsion/microemulsion and as a compounding base with textile resin plasticizers. Molecular Architecture: Diamino Sites + PDMS Backbone + Medium-Low Viscosity Film The core design of C803 comes from diamino-modified polysiloxane structure:

• Diamino Functionality: Amino groups on the chain can be protonated and orientate with anionic/polar fiber sites; dual sites improve retention and film continuity. Amino groups are strongly polar and reactive, contributing softness, lubrication, and anti-crease potential.
• PDMS Backbone: The Si-O-Si backbone is flexible and methyl groups give low surface energy, forming a continuous slip film on fibers to reduce static friction and improve drape and lively hand.
• Medium-Low About 300 mPa·s: Under low shear it is easily made into fine microemulsion with emulsifiers such as C13(EO)6, penetrating cellulosic/man-made yarn gaps more uniformly; compared with high-viscosity oils it is more suitable for napping/sanding lubrication with less roll-sticking and silicone spots.

Performance Leap: From "Soft But Refrosting" to "Smooth-Soft Drape-Strength Low-Yellow" Introducing C803 microemulsion/emulsion brings the following benefits:

• Smooth-Soft Hand: Dual-amino adsorption plus siloxane lubrication gives cellulosic and man-made woven/knit a smooth yet soft hand without relying on high-viscosity thickening.
• Good Drape: Low-modulus silicone film reduces fabric boardiness, improving drape and flowing fall, suitable for shirts, dresses, and man-made home textiles.
• Low Yellowing: Medium-low amine diamino positioning with weakly acidic microemulsion process helps control light-shade yellowing under reasonable setting; actual whiteness must be trialed.
• Elasticity and Crease Recovery: The silicone film supplements elasticity and reduces crease permanent set, improving crease-recovery angle and supporting wash-and-wear/ machine-wash performance.
• Strength Improvement: Film lubrication allows interfiber sliding and distributes external force, improving tensile and tear strength; especially useful as compensation for napped/sanded damaged cloth.
• Resin Plasticizing Compounding: As a resin-plasticizing emulsion base, it can be compounded with textile resin systems to soften handfeel and reduce rigid-film harshness; compatibility is fixed by trial.

Application Penetration: From Man-Made Knit to Napping/Sanding C803 covers multiple cellulosic/man-made processes:

• Cellulosic Woven/Knit: Cotton, viscose, modal, lyocell for smooth-soft drape finishing, balancing white-cloth low yellowing and garment drape.
• Man-Made Nonwoven: Spunlace and thermal-bond nonwovens for soft lubricant and uniform hand.
• Napping/Sanding Lubrication: C803 microemulsion reduces fiber friction on napping and sanding machines, lowering breakage, roll-sticking, and streak marks.
• Resin Finishing Compounding: Co-compounded with urea-formaldehyde, melamine, or polyurethane textile resins for plasticizing; ratios are trialed by resin type.
• Auxiliary Mother Stock: Emulsified by the typical microemulsion formula, then tiered into smooth-soft, low-yellowing, and elastic compounds.

IOTA Technical Guide: Typical Microemulsion, Weak-Acid Fine Particle

• Typical microemulsion formula (typical, not mandatory): ECOSOFT IOTA C803 20%, glacial acetic acid 0.2%, surfactant C13(EO)6 8%, diethylene glycol monobutyl ether 2%, deionized water 69.8%.
• Process: Mix water, acetic acid, diethylene glycol monobutyl ether, and C13(EO)6; stir evenly; heat to 45–50℃; slowly add C803 under continuous stirring until complete; keep stirring for full oil-phase dispersion; continue stirring and cool below 30℃; filter to remove impurities and undissolved gel particles.
• Application: Exhaust/pad dosages are fixed by target hand, fabric weight, and microemulsion solids through trial; napping/sanding lubrication can adjust pick-up by roll pressure and cloth speed. For medium-low viscosity diamino microemulsion, start with 20% oil phase for trial, then back-calculate working-liquor concentration; do not apply other grades' dosages to C803.
• ⚠️ Taboo: For light/bleached cloth, run pre-setting and post-setting Δb/ΔE trials; diamino is medium-low amine but still affected by heat and light; acetic acid is only for microemulsion pH/stability, avoid direct mixing with strong alkali; for high-viscosity compounds or hard water, test emulsion particle size and centrifugal stability; reseal after use to prevent amine-odor volatilization and moisture uptake; filter out gel particles before use.
• Storage: 200kg drum (800kg per pallet), plastic drum; store in original closed containers at 2–30℃; standard shelf life 12 months from production date, beyond which follow manufacturer re-inspection. Unlike 209 series 0–40℃/18 months, C803 follows this temperature range and period.

Industry Insight: The value of diamino medium-low-viscosity silicone oil lies in "dual sites for retention, medium-low viscosity for penetration/microemulsion, weak-acid microemulsion for yellowing control, resin compounding for plasticizing". C803, with "diamino PDMS, about 300 mPa·s, 4200 ppm N, 100% active, flash point 104℃, typical microemulsion C13/acetic acid/diethylene glycol monobutyl ether", fills the soft-drape base link of domestic diamino crude oil in cellulosic/man-made softening, napping/sanding lubrication, and resin-plasticizing compounding. For auxiliary manufacturers, it can serve as a microemulsion mother stock, then be subdivided by slip, whiteness, elasticity, and resin hardness, upgrading the smooth-soft drape premium of man-made and cellulosic fabrics along the path of "general PDMS → single-amino soft oil → diamino medium-low-viscosity soft-drape oil".