VERNIUM AB 2480

For dyeing of polyester fibres with disperse dyes at all stages of processing in HT processes on jets and circulating liquor machines. VERNIUM AB 2480 acid buffer is recommended for pH-sensitive dyes such as some disperse dyes, and for dyeing of polyester blends. Also suitable for dyeing wool fibres with suitable dyes at the proposed pH 4.5–5 of the acid dyeing system, or any fibre requiring pH 4.5.

Characteristics

• Good buffer capacity.
• No problem with correct pH measurement.
• No impact on fastness.
• No extra addition of acid required to adjust the pH.

Benefits

• Robust "right first time" dyeing system, hence cost savings.
• No pH change through electrolytes and added substances in the dyebath.
• No impact on pH from impurities of the fibre or water; compatible with all auxiliaries.
• Easy and safe handling.
• Suitable for jets.

Specifications

• Chemical constitution: Organic acid and salts
• Ionic character: Anionic
• Physical form: Clear colourless to slightly yellowish liquid
• pH (5% solution): 3.5 to 4.5
• Specific gravity at 20°C: About 1
• Viscosity: <250 mPa·s (D=100s⁻¹) at 25°C
• General stability: Stable in hard water, to acids, alkalis and electrolytes in usual amounts.
• Storage stability: Stable for 1 year at 20°C in closed containers, not affected by heat or cold.
• Compatibility: Can be used with anionic and nonionic products if carefully applied.

Applications

VERNIUM AB 2480 is added at the start of the (HT-) exhaust dyeing cycle, diluted with water in all proportions, and added to the dyebath before the dyes.

For PES fibres: A complete acid dyeing buffer requiring no further acid. Typical amount: 2.0 g/l.

For wool fibres (acid dyes): Typical amount 3.0–5.0 g/l, depending on kind of wool, alkalinity/acidity, dye and liquor ratio.

Notes — PES

Due to its excellent buffer capacity, higher amounts of alkali might be required for one-bath-two-step dyeing of PES/CEL blends with disperse/reactive dyes. For short liquor ratios below 7:1, use 1–2% on weight of goods. If the bath contains impurities such as Ca²⁺, Mg²⁺, Fe³⁺ or Cu²⁺, an addition of 0.2–1.0 g/l VERNIUM LEVEL 4420 is recommended.

Notes — Wool

Due to the high acid affinity of wool fibre, usage is generally higher than for PES fibres. For liquor ratios of 10:1 and below, use at least 5%; trials are recommended to achieve pH 4.5–5. Can also be used for wool blends such as PES/WO or PAN/WO.

Packing

This product is supplied in HDPE drums of 50 kg and 200 kg net.

Storage and Handling

It is recommended to use personal protective equipment like safety glasses, face shield and protective hand gloves. Any splash in the eyes or on the skin must be washed by plenty of running water.