physical properties at 20°C	unit	VOS	HL	HT
bulk density	g/cm3	1.18	1.18	1.18
water absorption (96 h)	mg/10 cm3	45	45	45
mechanical properties
tensile strength	N/mm2	75	70	70
elongation at break	%	4.5	4.0	4.0
bending strength	N/mm2	135	125	125
modulus of elasticity	N/mm2	3300	3200	3000
notched impact strength	kpcm/cm3	2	2	3
cross-linking		no	poor	strong
surface hardness	pencil	1H	3H	3H
thermal properties
vicat softening point	°C	100-105	114-118	120-122
temp. of dimensional stability	°C	100	100	105
continuous operating temperature	°C	70	75	75
linear coefficient of thermal expansion (0-50°C)	K-1	70 x 10-6	70 x 10-6	70 x 10-6
thermal conductivity	kcal/mh °C	0.19	0.19	0.19
deformation temp.	°C	130-150	160-180	160-180
fire behaviour	UL 94	HB	HB	HB
optical properties
refractive index	nD20	1.492	1.492	1.492
light transmission (380-780 nm)	%	92	92	92
electrical properties
surface resistance	Ω	> 1014	> 1014	> 1014
volume resistivity	Ω	1014	1014	1014
dielectric strength	kV/mm	30	30	30
dielectric loss factor (50 Hz ~)		0.06	0.06	0.06
dielectric constant (50 Hz ~)		3.6	3.6	3.6
leakage current resistance	Kc	> 600	> 600	> 600