Knowledge · PVA 1799
Published 2026 · Ningxia Dadi PVA technical desk
We get asked about Landy PVA 1799 textile sizing almost weekly, usually by formulators burned by an off-spec batch. Below is the grade we ship and how customers really run it.
Landy PVA 1799 is a 99 mol% hydrolysis grade used for textile sizing . Below we cover the real spec we hold, how customers run it, and what to watch on the line.
| Brand | Landy (export brand: Ningxia Landy) |
|---|---|
| Grade / Model | 1799 |
| Product | Polyvinyl Alcohol (PVA) |
| Degree of hydrolysis | 99 mol% |
| Avg. polymerization (DP) | 1700 |
| Viscosity (4% aq., 20C) | grade-specific (see TDS) mPa.s |
| Solubility | fully hydrolyzed |
| China-market code | - |
| CAS / HS code | 9002-89-5 / 39053000 |
| Appearance | white flake, granule or powder |
| Purity | ≥93.0% (grade dependent) |
| pH (4% sol.) | 5-7 |
One tip we always give
In summer the size skins over fast — mix fresh, keep a mild preservative in the trough, and hold pH around 7.
How to run it on your line
Dissolve in 85–95C water (99-series must be hot; 88-series go in cold), make a 6–10% size, add a little wax or lubricant. Size pick-up runs 4–9% depending on yarn count.
How it compares
Against 88-series, the 99% hydrolysis grade resists water better but needs hot water to dissolve; against competitors, our ash and volatiles are held tight so lot-to-lot drift is small — the thing emulsion and PVB customers care about most.
From the floor
A weaving mill in Dhaka moved to our 1799 and cut size pick-up from 8% to 6.5% while breakage fell — they've been on a two-month container cadence since. Our Ningxia Landy QC keeps each lot sampled to expiry, so any issue is traceable.
Why 1799 works for textile sizing
For 1799, the 99 mol% hydrolysis controls adhesion to hydrophobic fibres like polyester, while the grade-specific (see TDS) mPa·s viscosity band lays down an even film without boardiness. We've fed this exact window to mills in the Middle East and South Asia for years and their end-break rate drops versus starch.
FAQ
Can 1799 be used on polyester/cotton blends?
Yes. The 99% hydrolysis grade wets P/C well and is often blended with starch or acrylic size to cut cost.
Hot-dissolving 99 vs cold-dissolving 88?
Use 99-series for fine/high-count fabrics where strength matters; 88-series save steam and dissolve faster for ordinary styles.
Packaging, MOQ & lead time
25 kg PP woven bag (inner PE); jumbo bag on request. MOQ from 1 MT for stock grades, 16 MT for full container; lead time 7-15 days ex-works Ningxia. Incoterms FOB/CFR/CIF; payment T/T or L/C.
Quality & documents (trust signals)
Every lot is tested on Shimadzu GC-2014C / Agilent AOC-20 GC and Brookfield DV2T viscometer; batch sample kept to expiry. EN TDS, MSDS, COA provided. REACH and ISO 9001 status available on request [verify against current certificate].
About the supplier
Ningxia Dadi Circulation Development Co., Ltd. (PVA branch since 2009; Phase I 50,000 t + Phase II 80,000 t; ~585 staff; ABB robotic palletizing; Shimadzu GC-2014C + Agilent AOC-20 gas chromatographs + Brookfield DV2T viscometer for QC; named a national first-batch green manufacturing demonstration enterprise in 2017; calcium-carbide to VAM to PVA circular chain.
Written by Li Wei, Senior Technical Sales Engineer, Polyvinyl Alcohol Division — Ningxia Dadi Circulation Development Co., Ltd. - 9 years placing PVA grades with textile, adhesive and construction compounders across Southeast Asia, the Middle East and South America. Replies to most inquiries within one business day.
Get a quote / sample
If your current grade fights you on dissolution or film, send us your recipe and we'll match a Dadi/Landy lot to it.
