LJA99
LJA99 clear 2K acrylic sanding sealer
Two-pack clear acrylic (acrylic-urethane, cured with the aliphatic LNB99 hardener) sanding sealer. Its main point is maximum resistance to yellowing — it won't amber light, bleached or stained timber, so colour and grain stay clean. Sands well, dries fast and keeps the pores crisp rather than burying them. Solids are low (~26 %), so treat it as a clear sealer under acrylic lacquers, not a high-build filler.
- sealing furniture, cabinet doors and mouldings in pale, bleached or stained timber under acrylic lacquers (LUA46x, ATL series, etc.)
- open-pore and semi-open-pore finishes — it doesn't fill the grain
- the sealer for non-yellowing clear systems where an aromatic-cured PU sealer would amber
- veneer and solid timber of any species incl. resinous softwoods and exotics (test exotics first, per TDS)
Mix calculator
Ask about LJA99
Answers are based on the LJA99 data and the products it mixes with.
Mixing matrix
- LNB99Hardener% by weight: 10–20 %official% by volume: 10–20 %official
Always. Use 20 % by weight (19.5 % by volume) — that's the maker's TDS recipe. Technocolor lists 10–20 %, but going under 20 % just gives a less cured, gummier sealer — no reason to.
LNB99 is a non-yellowing acrylic hardener, 32 ± 1 % solids (dealer) / 31.4 ± 2 % (TDS), 0.954 kg/l. Moisture-sensitive — lid straight back on. Sold in 1, 2.5 and 5 L.
- LZC1026Thinner% by weight: 20–30 %official% by volume: 20–30 %official
Standard thinner for normal 18–22 °C conditions. 30 % (32 % by volume) is the TDS recipe and gives 18 ± 2 s Ford 4 for spraying. 20–25 % if you want a bit more film per pass on verticals or you're on airless/airmix.
LZC1026 density 0.883 kg/l (TDS). Thinner is calculated on part A only.
- LZC8643Thinner% by weight: 20–30 %official% by volume: 20–30 %official
Slow thinner — hot shop (above ~25 °C), big flat panels, or when the sealer goes on dry, orange-peels or pops.
More open time to flow, but more dust pick-up and more sag risk on verticals. Officially a thinner for PU and acrylic materials.
- LTC206Additive% by weight: 1–2 %datasheet
Optional — when you want extra light protection (pale timbers near windows, bleached oak, maple, birch).
Milesi UV absorber. No Technocolor page for it — check availability with the dealer.
| Role | Material | % by weight | % by volume | When |
|---|---|---|---|---|
| Hardener | LNB99 | 10–20 %official | 10–20 %official | Always. Use 20 % by weight (19.5 % by volume) — that's the maker's TDS recipe. Technocolor lists 10–20 %, but going under 20 % just gives a less cured, gummier sealer — no reason to.LNB99 is a non-yellowing acrylic hardener, 32 ± 1 % solids (dealer) / 31.4 ± 2 % (TDS), 0.954 kg/l. Moisture-sensitive — lid straight back on. Sold in 1, 2.5 and 5 L. |
| Thinner | LZC1026 | 20–30 %official | 20–30 %official | Standard thinner for normal 18–22 °C conditions. 30 % (32 % by volume) is the TDS recipe and gives 18 ± 2 s Ford 4 for spraying. 20–25 % if you want a bit more film per pass on verticals or you're on airless/airmix.LZC1026 density 0.883 kg/l (TDS). Thinner is calculated on part A only. |
| Thinner | LZC8643 | 20–30 %official | 20–30 %official | Slow thinner — hot shop (above ~25 °C), big flat panels, or when the sealer goes on dry, orange-peels or pops.More open time to flow, but more dust pick-up and more sag risk on verticals. Officially a thinner for PU and acrylic materials. |
| Additive | LTC206 | 1–2 %datasheet | — | Optional — when you want extra light protection (pale timbers near windows, bleached oak, maple, birch).Milesi UV absorber. No Technocolor page for it — check availability with the dealer. |
Percentages are per 100 parts of component A.
Characteristics
- Properties (official)
- Maximum yellowing resistance; Good sandability; Fast drying; Good pore definitionofficial
- Solids
- 26.1 ± 2 % (part A, by weight)datasheet
- Ready-mix solids %
- 27.0 ± 2 % (A + 20 % LNB99, before thinner)datasheet
- Spray-mix solids %
- ≈ 21.6 %recommended
- Viscosity · Part A
- 31 ± 3 sdatasheet
- Viscosity · Ready to spray
- 18 ± 2 sdatasheet
- Density
- 0.930 ± 0.030 kg/l (part A)datasheet
- Pot life
- 3 h at 20 °Cdatasheet
- Drying · Dust-free
- 10 mindatasheet
- Drying · Touch-dry
- 30 mindatasheet
- Drying · Sand or stack
- 4 h (sandable after)datasheet
- Drying · Recoat between layers (h)
- 1 h (overcoat between layers)datasheet
- Drying · Max without sanding (h)
- 3 h (maximum time between layers without sanding)datasheet
- Drying · Overcoat with topcoat (h)
- 12–24 h (overcoatability time)datasheet
- Drying · Hard dry (h)
- 12–24 hdatasheet
- Drying · Full cure
- 24 h (complete drying)datasheet
- Drying · Conditions
- 18–22 °C, 65–70 % RH (TDS)
- Lightfastness
- Excellent yellowing resistance ('maximum' per Technocolor). For extra light protection add 1–2 % LTC206 UV absorber.datasheet
- Hardness
- medium — sandable sealer film, softer than a topcoatrecommended
- Elasticity
- good — aliphatic acrylic-urethane, thin filmrecommended
- Thixotropy
- norecommended
Colours
- LJA99 · clear
Application
HVLP
- Nozzle
- 1.4–1.6 mmrecommended
- Pressure · air
- 2–2.2 bar at gun inlet with trigger pulled, ≤ 0.7 bar at the air caprecommended
- Spray viscosity
- 18 ± 2 s Ford 4datasheet
- Consumption
- 100–150 g/m² per coatdatasheet
- Wet film
- 109–163 µmdatasheet
- Coats
- 1–2 coatsrecommended
- Flash-off
- 10–15 min between crossing passes; ≥ 1 h before the next coatrecommended
- Recoat
- after 1 h; max 3 h without sanding, otherwise sanddatasheet
- Sanding between coats
- 320–400 gritrecommended
15–20 cm gun distance, 50 % overlap. Light pass on the edges first, then the faces. Official method: spray at 150 g/m².
Conventional spray
- Nozzle
- 1.5–1.8 mmrecommended
- Pressure · air
- 2.5–3.5 bar at gunrecommended
- Pressure · fluid
- 0.8–1.5 bar (pressure pot)recommended
- Spray viscosity
- 18 ± 2 s Ford 4datasheet
- Consumption
- 100–150 g/m² per coatdatasheet
- Wet film
- 109–163 µmdatasheet
Airmix (air-assisted airless)
- Nozzle
- 0.23–0.28 mm (09–11 thou tip, narrow 20–40° fan for parts, 40–60° for panels)recommended
- Pressure · fluid
- 30–50 barrecommended
- Pressure · air
- 1–2 barofficial
- Spray viscosity
- 18–25 s Ford 4 (20–30 % LZC1026)recommended
- Consumption
- 100–150 g/m² per coatdatasheet
- Wet film
- 109–163 µmdatasheet
Good choice for production sealing of doors and fronts: high transfer, little overspray.
Airless
- Nozzle
- 0.23–0.28 mm (09–11 thou tip)recommended
- Pressure · fluid
- 80–120 barrecommended
- Consumption
- 100–150 g/m² per coatdatasheet
- Wet film
- 109–163 µmdatasheet
Technocolor's methods page rates airless as ideal for primers on big flat parts (doors, tops, panels). It's a thin material — watch for bounce-back and fan tails.
Electrostatic
Not in the TDS. Any spray system can run electrostatic (Technocolor methods page) — test first; the mix's conductivity isn't published.
Curtain coater
- Consumption
- 100–150 g/m²datasheet
- Wet film
- 109–163 µmdatasheet
Flat panels only; set curtain viscosity to the machine (usually heavier than spray viscosity).
Process and compatibility
- Substrate preparation
- Timber at 8–14 % MC. Sand to P150–P180 (solid/veneer), dust off. Let stain/dye dry fully and do a test panel. Exotics — always run a test cycle first (TDS).recommended
- Sanding
- After 4 h (TDS) — P320, P400 on pale close-grained timber. Next day it sands even cleaner. Don't cut through on edges.recommended
- Don'ts
- don't go under 20 % LNB99 to 'save hardener' — it under-cures and loads the paper
- don't overcoat after 3 h without sanding — you lose intercoat adhesion
- don't flood it on for build — it's a sealer (~22 % solids at spray), not a filler
- don't apply or dry below 15 °C or above 30 °C
- decant only into polyethylene or stainless containers
- don't leave the LNB99 can open — moisture kills the hardener
Storage
- Shelf life
- 18 months after productiondatasheet
- Storage temperature
- 0–35 °C, indoors, ventilated, out of direct sundatasheet
- Packaging
- 5 L (US distributor SKU IVM-LJA99-5L)dealer
Safety: Two-pack solvent-borne: isocyanates in the LNB99 hardener, flammable solvents. Spray only in an extracted booth with spark-proof kit, carbon-filter respirator A2P2/A2P3 (or air-fed), nitrile gloves, goggles. No smoking. Clean the gun straight after use.
Mixed into
Sources
Value tags: “official”, “dealer”, “catalog”, “schedule” are Technocolor data; “workshop” is from our own datasheets; “recommended” is our engineering estimate (hover to see the reasoning).
- official page: properties, spray 150 g/m², LNB99 10–20 % w/w & v/v, LZC1026/LZC8643 20–30 % w/w & v/v
- IVM/Milesi Technical Data Sheet LJA99 (2019-09 rev.4): density 0.930, solids 26.1 %, viscosity 31 s Ford4, LNB99 20 % w/w (19.5 % v/v), LZC1026 30 % w/w (32 % v/v), ready mix 27 % solids / 18 s, pot life 3 h, 100–150 g/m² by airless/airmix/robot/curtain/hand spray, dust free 10 min, touch 30 min, sand 4 h, recoat 1–3 h, full 24 h, shelf life 18 months, LTC206 1–2 %
- US Milesi distributor (Access Marketplace): description, 5 L SKU, link to the TDS
- official dealer LNB99 page: non-yellowing acrylic hardener, solids 32 ± 1 %, MILESI, 1/2.5/5 L
- official dealer LJA99 page — 301 → 404, delisted
- official LZC8643 page: slow PU thinner for PU and acrylic materials
- Pro Wood (Milesi US distributor) LLA6020 application sheet: spray table for clear PU sealers/topcoats (class guidance for tips/pressures); names LJA99 as the sealer for non-yellowing acrylic PU systems; LNB99 is the only acrylic catalyst
- Technocolor application methods page (airless ≤200 bar, airmix ≤20 bar fluid / 1–2 bar air, electrostatic)
- Technocolor characteristics glossary
- official dealer search: LJA99 still listed with manufacturer MILESI, but links to a 404 page
Not covered by the sources
- Official dealer t-colormarket.ru: LJA99 page delisted (404) — no dealer solids/viscosity/drying/pack sizes in Russia; TDS (IVM 2019-09 rev.4) used instead
- Conflict: official LNB99 10–20 % w/w vs TDS fixed 20 % w/w; official thinner 20–30 % vs TDS 30 % — record keeps official range with TDS default
- Not in the Technocolor 2025-2026 catalog transcripts nor in any official finishing schedule (information/technology)
- No sourced spray-gun tip/pressure for LJA99 itself (all nozzle/pressure values derived, with Milesi class guidance as reference)
- Hardness, chemical resistance, elasticity values not published
- LTC206 UV absorber has no Technocolor page — availability in Russia unknown
- SDS / hazard classification not retrieved
- Electrostatic suitability (mix conductivity) not published