← EXPLODED VIEWL06
MATERIAL-LAYER TECHNICAL DOSSIER
ThermoSnow Active Layer
A reversible thermochromic pigment changes absorption and contrast within a temperature window.
PRE-INDUSTRIAL R2REVERSIBLE THERMOCHROMIC SIGNAL
01 · PRINCIPLE & RATIONALE
Intended function
and associated requirement.
A reversible thermochromic pigment changes absorption and contrast within a temperature window.
Makes cold perceptible through a passive symbol without electronics.
Threshold, hysteresis, response time, ΔE, uniformity, light stability and migration depend on chemistry, thickness and thermal coupling.
02 · TECHNOLOGY STACK
Technologies, roles
and approval gates.
Material and process qualification
- Role
- Converts the design basis into a repeatable specification.
- Why
- Performance depends on the real commercial grade and process window.
- Approval gate
- Documented test evidence and approved specification.
03 · ARCHITECTURE
Function, material
and interfaces.
The reading must be clear without being presented as a numerical thermometer or potability guarantee.
- Thermal bridge L02
- Film L07
- External environment
- Vision system
- 01Target 20–40 µm layer
- 02Reversible microcapsules
- 03Compatible binder
- 04Localised symbol
04 · MASTER PARAMETER REGISTER
Everything to be defined,
measured or certified.
A field without evidence is never filled with an invented number: it remains “To be determined”, together with the method required to close it. This is what makes the technical record verifiable.
DESIGN BASISTARGETCALCULATED / MEASUREDTO BE VALIDATEDCERTIFICATION REQUIRED
01Identification & function1 PARAMETERS
| ID | Parameter | Symbol | Value | Unit | Tolerance | Condition | Method | Status |
|---|---|---|---|---|---|---|---|---|
| L06-X001 | Intended use | USE | To be determined | — | To be defined | Full use cycle | Design review + user study | TO BE VALIDATED |
02Geometry & metrology1 PARAMETERS
| ID | Parameter | Symbol | Value | Unit | Tolerance | Condition | Method | Status |
|---|---|---|---|---|---|---|---|---|
| L06-X002 | Nominal mass | m | To be determined | g | To be defined | 23 °C / 50% RH | Balance 0.001 g | TO BE VALIDATED |
03Material1 PARAMETERS
| ID | Parameter | Symbol | Value | Unit | Tolerance | Condition | Method | Status |
|---|---|---|---|---|---|---|---|---|
| L06-X003 | Commercial grade and supplier | GRADE | To be determined | — | Qualified grade | Production lot | CoA + traceability | TO BE VALIDATED |
04Thermal properties1 PARAMETERS
| ID | Parameter | Symbol | Value | Unit | Tolerance | Condition | Method | Status |
|---|---|---|---|---|---|---|---|---|
| L06-X004 | Service-temperature range | Tservice | To be determined | °C | To be defined | Use and transport | Climate chamber | TO BE VALIDATED |
05Mechanical properties1 PARAMETERS
| ID | Parameter | Symbol | Value | Unit | Tolerance | Condition | Method | Status |
|---|---|---|---|---|---|---|---|---|
| L06-X005 | Drop resistance | Hdrop | To be determined | m | To be defined | Defined orientations | Instrumented drop test | TO BE VALIDATED |
06Quality control1 PARAMETERS
| ID | Parameter | Symbol | Value | Unit | Tolerance | Condition | Method | Status |
|---|---|---|---|---|---|---|---|---|
| L06-X006 | Process capability | Cpk | To be determined | — | Target to be defined | Critical CTQ | SPC ≥30 samples | TO BE VALIDATED |
07Food contact1 PARAMETERS
| ID | Parameter | Symbol | Value | Unit | Tolerance | Condition | Method | Status |
|---|---|---|---|---|---|---|---|---|
| L06-X007 | Overall and specific migration | MIG | To be determined | mg/kg | Applicable limits | Simulant/time/temperature | Accredited methods | TO BE VALIDATED |
08Recyclability1 PARAMETERS
| ID | Parameter | Symbol | Value | Unit | Tolerance | Condition | Method | Status |
|---|---|---|---|---|---|---|---|---|
| L06-X008 | Territory-specific end-of-life route | EOL | To be determined | — | Country/area defined | Complete assembly | Infrastructure mapping | TO BE VALIDATED |
05 · INDUSTRIALISATION
From material
to final inspection.
Qualified material
Thermochromic microcapsules in a compatible binder
Process within window
Local printing/deposition + encapsulation
Controlled interfaces
Thermal bridge L02 · Film L07 · External environment · Vision system
CTQ + traceability
The deposit must be positioned, inspected optically at 100% and protected without altering its response.
06 · DVP&R
A function is approved
only after passing its test.
| Test | Requirement | Risk | Method | Condition | Samples | Acceptance | Output |
|---|---|---|---|---|---|---|---|
| DVP-05 | Condensation management | Wet grip | Climate + gravimetry | 25 °C/60% RH; water 4 °C | 30 | ≥60% less retained water | Mass + images |
| DVP-06 | ThermoSnow | Incorrect threshold | Thermal/colour cycles | 0–25 °C | 30 | 8±2 °C; ≤15 s | ΔE/T curves |
| DVP-12 | Food contact | Migration/NIAS | Overall/specific migration | Cold-fill water use | 3 lots | Applicable regulatory compliance | Signed report |
07 · FAILURE MODES
Failure modes,
causes and controls.
Body brittleness
EffectBreakage/leak
CausePHA thermal window
ControlDSC/TGA, rheology, process DOE
Non-uniform walls
EffectBuckling/drop failure
CauseAsymmetric geometry
ControlBlow-moulding CAE + micro-CT
AeroSkin detachment
EffectLoss of function/loose part
CauseInsufficient seal
ControlPeel, thermal cycling and drop
08 · EVIDENCE POLICY
Traceability
for every parameter.
Avoids a battery and circuit, but introduces microcapsules requiring containment and end-of-life assessment.
This page is the technical register for the R2 configuration. It separates design values, targets, calculations, measurements and certifications. Open fields identify the exact test or document required to close them.