Surface coating

$\alpha$

$\epsilon$

$\frac{\alpha }{\epsilon }$

The balance temperature of balloon bait during daytime (K)

White TiO₂coatings

0.19

0.94

0.20

226.5

White epoxy coatings

0.248

0.924

0.27

236.9

White enamel

0.252

0.853

0.30

240.8

Polyester film

0.17

0.5

0.34

246.8

Aluminum silicon coating

0.25

0.28

0.89

299.2

Grey TiO₂

0.87

0.87

1.00

306.7

Black paint

0.975

0.874

1.12

314.3

Aluminum based coatings

0.54

0.45

1.20

319.4

Aquadag coatings

0.782

0.49

1.60

340.9

Aluminum foil

0.192

0.036

5.33

454.4

Polishing gold coating

0.301

0.028

10.8

539.7