DUN-DIFFUSE™ is a white Kapton® polyimide film engineered as a stable cold surface for spacecraft, used as the protective outer layer of MLI blankets or as a radiator second-surface mirror (SSM). The 25 µm (100-gauge) film is metallized with vacuum-deposited aluminum and combines high emissivity with moderate solar absorptance, giving a lower α/ε ratio than standard outer-layer films. Thermal engineers specify it as an alternative to white thermal-control paint, with better adhesion than a painted coating.
White thermal-control paints deliver the low-α/high-ε surface spacecraft need, but coatings can be difficult to apply uniformly and can degrade or flake. DUN-DIFFUSE™ delivers the same class of thermal performance as a converted film with better adhesion, applied like any other MLI layer.
The outer layer sets an MLI blanket's external thermal balance. High emissivity and moderate absorptance keep that surface cold and stable.
Plain White Kapton® WS/VDA, an ITO conductive coating for ESD-critical surfaces, or StaMet® coating.
DUN-DIFFUSE™ is a 25 µm white Kapton® polyimide film metallized with vacuum-deposited aluminum, available plain or with ITO or StaMet® conductive coatings.
| Property | Value |
|---|---|
| Film | White Kapton® polyimide |
| Thickness | 25 µm (100 gauge) |
| Metallization | Vacuum-deposited aluminum (VDA) |
| Emissivity (ε) | High |
| Solar Absorptance (α) | Moderate |
| α/ε Ratio | Lower than standard outer-layer films |
| Constructions |
ITO / White Kapton® WS / VDA
White Kapton® WS / VDA StaMet® / White Kapton® WS / VDA |
The primary application is the outer layer of multi-layer insulation blankets, where the film takes the direct space environment and sets the blanket's exterior thermal balance.
As a radiator SSM it provides a cold, stable radiating surface on radiator panels. Programs that would otherwise specify white thermal-control paint use DUN-DIFFUSE™ where a film's uniformity, handling, and adhesion are preferred over a coating.
The ITO construction serves exterior surfaces with electrostatic cleanliness requirements.
Dunmore Aerospace has manufactured thermal control materials for the space industry since 1985 from Bristol, Pennsylvania. Dunmore materials flew on NASA's Cassini mission, documented in NASA's Spinoff 2016 report. Dunmore is ISO 9001:2015 certified.
Aerospace material solutions since 1985.
Dunmore materials supported NASA's Cassini mission.
ISO 9001:2015 certified.
White Kapton is DuPont™ Kapton® polyimide film pigmented white, giving polyimide's temperature and radiation tolerance with the optical properties of a white thermal-control surface. DUN-DIFFUSE™ is Dunmore's converted white Kapton® product, metallized with vacuum-deposited aluminum.
An SSM is a thermal control surface where sunlight passes through the outer material and reflects off a metallized back surface, keeping absorptance low while the outer surface emits heat. DUN-DIFFUSE™ serves this role with its VDA backing.
It is an alternative for many exterior surfaces: a white, high-emissivity surface without a coating process, with better adhesion than paint. Films suit flat and gently curved surfaces; paint suits complex shapes.
The ITO/White Kapton® WS/VDA construction adds an indium tin oxide conductive layer for surfaces with electrostatic discharge and charging requirements.
25 µm, equivalent to 100 gauge, metallized with vacuum-deposited aluminum on one side.
Request complete product details, technical data, samples, or assistance selecting the right construction for your thermal-control and ESD requirements.