C50
C50 PU hardener (legacy code)
Legacy code for the isocyanate second component of Technocolor PU coatings. It appears only in the official 'Beech chairs (PU)' finishing schedule, as the hardener for PTS50 thixotropic clear primer and PTL50 thixotropic lacquer at 2:1 (50 % on part A). The code is not in the current range, the dealer shop or the 2025–26 catalogue. For the same two products Technocolor now specifies PC20 or PC25 at the same 50 %, so in practice 'C50' means 'use PC20/PC25'.
- second component of PTS50 primer (100 : 50) in the beech-chair schedule
- second component of PTL50 lacquer (100 : 50) in the same schedule
Ask about C50
Answers are based on the C50 data and the products it mixes with.
Mixing matrix
- C50Hardener% by weight: 50 %schedule
priming beech chairs, 2 coats at 150 g/m², 2 h at 30–35 °C, sand K120 after each
The schedule doesn't say weight or volume; the official PTS50 page gives 50 % by both, so it makes no difference. The schedule uses slow S80 (warm drying, chair components) rather than the standard S50.
- C50Hardener% by weight: 50 %schedule
topcoat on beech chairs, 150 g/m², 2 h at 30–35 °C
The schedule doesn't name the PTL50 gloss grade (G/SG/SM/M all take 50 % hardener).
- % by weight: 50 %official% by volume: 50 %official
use today in place of C50
Same schedule recipe: PTS50 100 / PC20 50 / S80 20; PTL50 100 / PC20 (PC25) 50 / S80 30. Weigh it.
| Role | Material | % by weight | % by volume | When |
|---|---|---|---|---|
| Hardener | C50 | 50 %schedule | — | priming beech chairs, 2 coats at 150 g/m², 2 h at 30–35 °C, sand K120 after eachThe schedule doesn't say weight or volume; the official PTS50 page gives 50 % by both, so it makes no difference. The schedule uses slow S80 (warm drying, chair components) rather than the standard S50. |
| Hardener | C50 | 50 %schedule | — | topcoat on beech chairs, 150 g/m², 2 h at 30–35 °CThe schedule doesn't name the PTL50 gloss grade (G/SG/SM/M all take 50 % hardener). |
| Hardener | PC20 / PC25 | 50 %official | 50 %official | use today in place of C50Same schedule recipe: PTS50 100 / PC20 50 / S80 20; PTL50 100 / PC20 (PC25) 50 / S80 30. Weigh it. |
Percentages are per 100 parts of component A.
Characteristics
- Chemistry
- aromatic isocyanate (polyisocyanate adduct in solvent), 2K PU hardenerrecommended
- Solids
- ≈ 27–28 (if equivalent to PC20/PC25) %recommended
- Pot life
- 4 hdealer
- Drying · Sand or stack
- 2 hschedule
Application
Mix component
Add hardener to part A (not the other way round), stir thoroughly, let it stand 5–10 min, strain; add thinner after the hardener. Close the tin straight away.
Process and compatibility
- Goes with
- PTS50, PTL50
- Temperature and humidity
- mix and apply at 18–25 °C, RH ≤ 70 %; forced dry 30–35 °C as per schedulerecommended
- Don'ts
- don't mix an old C50 tin with PC hardeners in one batch
- don't go under or over — the 2:1 ratio is fixed
- don't use hardener that has gone cloudy, thick or skinned — moisture has got to it
- don't use it with acrylic (ATL/ATS) or polyester materials
Storage
- Storage temperature
- +5…+25 °C, tightly closed, dryrecommended
Safety: Contains isocyanates and organic solvents: spray in a booth, wear an A2 carbon-filter respirator (air-fed is better), nitrile gloves and goggles. Flammable. Keep it off your skin — isocyanates sensitise.
Used in finishing systems
Mixed into
C50 / PTL50 G / PTL50 M / PTL50 SG / PTL50 SM / PTL50 UM / PTL50090 / PTS50
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).
- only mention of C50: PTS50 100 / C50 50 / S80 20 (x2) and PTL50 100 / C50 50 / S80 30, 150 g/m², 2 h at 30–35 °C
- current PTS50 hardener: PC25/PC20 50 % by weight and volume
- current PTL50 G hardener: PC20 50 %
- dealer PTS50: PC25 50 %, pot life 4 h
- dealer PTL50 G: PC20/PC25 50/50, pot life 4 h
- dealer hardener list — no C50/PC50
- no results (also С50, PC50)
- PC20 (legacy slug c20): solids 28 ± 1 %
- PC25 (legacy slug c25): solids 28 ± 1 %
- PTL50 M/SG/SM dealer pages: PC20/PC25 50/50, pot life 4 h
Not covered by the sources
- no official page, no dealer page, not in 2025–26 catalogue — code appears only in the beech-chair schedule
- exact chemistry/identity of C50 not confirmed (equivalence to PC20/PC25 is derived)
- solids, density, viscosity of the hardener itself
- whether the schedule 50 % is by weight or volume (moot for PTS50/PTL50: official 50 % both)
- PTL50 gloss grade used in the schedule
- shelf life, packaging
- no TDS/SDS PDF found (web search budget exhausted; dealer and woodonline searches returned nothing)