Specification for 3M
Full Cube Microprismatic Retroreflective
Sheetings
3M™ Diamond Grade™
DG3 Reflective Sheeting Series 4000
Issued:
April 2007
1
1. Scope
This specification covers non-fluorescent full cube microprismatic retroreflective sheeting
designed for use on road traffic signs that are installed vertically in the UK and Ireland.
2. Description
The retroreflective sheeting shall have a smooth surface and a distinctive interlocking
diamond seal-pattern. The sheeting shall be pre-coated with a pressure sensitive adhesive
on the back, which is protected by a removable liner. The adhesive shall require no heat to
achieve an adequate bond to approved substrates when applied in accordance with the
manufacturer's instructions.
3. Test Methods
3(i)
Test Conditions: Unless otherwise specified herein, all applied and unapplied test
samples and specimens shall be conditioned for 24 hours at 23 o +/- 3 o Centigrade
and 50 +/- 5% relative humidity prior to testing.
3(ii)
Test Panels: Unless otherwise specified herein, when tests are to be performed on
applied test specimens, the retroreflective material shall be applied to smooth
aluminium alloy NS4 half-hard 1.6mm thick. The application surface of the
aluminium shall be degreased and lightly acid etched previous to the specimens being
applied.
4. Photometric and Colorimetric Requirements
4(i)
Colour and luminance:
When measured in accordance with the appropriate test methods detailed within BS
8408, the chromaticity and luminance of new material shall comply with Tables 2 and
3 of BS 8408:2005.
When exposed as required in section 5.4.5 of BS 8408:2005 and tested in accordance
with 5.2.1 or 5.2.2 of BS 8408:2005 after that exposure, the colour and luminance
shall conform to the chromaticity requirements specified in Tables 2 and 3 of BS
8408:2005.
4(ii)
Coefficient of Retroreflection R'
The coefficient of retroreflection of the sheeting series 4090 shall be not less than the
values specified in Table 1. Measurements shall be made in accordance with CIE
Publication 54.
4(iii)
Performance Index
BS 8408:2005 contains an extensive photometric test regime the results of which are
used in conjunction with headlight illumination data to calculate Performance Indices
for specific signing/driving situations. The Performance Index / Indices for a
particular road and sign scheme will be provided to specifiers on request.
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Table 1: Minimum Coefficients of Retroreflection :
3M™ Diamond Grade™ DG3 Reflective Sheeting Series 4090
Candelas per lux per square metre
Observation
Angle
(alpha)
Entrance
Angles
Beta 2
Beta 1
5
o
0o
15o
30°
40o
Colour
White
Yellow
Red
Blue
Green
W Green
650
530
160
42
100
50
510
420
130
30
78
35
250
145
115
30
8
22
11
20’ (0.33º)
White
Yellow
Red
Blue
Green
W Green
460
375
105
34
80
40
215
180
51
19
36
25
160
90
72
19
5
15
7
30’ (0.5º)
White
Yellow
Red
Blue
Green
W Green
390
325
95
26
70
35
285
245
67
20
50
25
79
60
15
5
13
6
1º
White
Yellow
Red
Blue
Green
W Green
115
100
30
8
20
10
90
76
23
6
16
8
41
32
9
2
6
3
1.5º
White
37
27
12
2.0º
White
10
9
12’
(0.2º)
7
6
NOTE 1:
Typical observation angles for car drivers - 12’, 20’ and 30’ on high speed roads
Typical observation angles for car drivers - 20’, 30’ and 1º on slower roads
Typical observation angles for truck drivers - 30’, 1.0º on high speed roads
Typical observation angles for truck drivers - 1.0º, 1.5º and 2.0º on slower roads
NOTE 2:
When exposed as required in section 5.4.5 of BS 8408:2005 and tested in accordance
with CIE Publication 54:1982, the coefficient of retroreflection measured at the 20'
observation angle and -5 degrees entrance angle shall be not less than 80% of the
values in Table 1.
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5. Physical Requirements
5(i)
Adhesion to the Substrate
When tested in accordance with section 5.3.1 of BS 8408:2005, the average peel
strength shall not be less than 20N per 25mm of sample width.
5(ii)
Salt Spray
After exposure to salt spray in accordance with section 5.3.2 of BS 8408:2005, the
coefficient of Retroreflection RA shall not be less than 90% of its value before
exposure.
5(iii)
Impact resistance
When tested in accordance with section 5.3.3 of BS 8408:2005, there shall be no
cracking, of the sheeting or delamination of the sheeting from the substrate outside a
circle of radius 6mm with the point of impact at its centre.
5(vi)
Hermaticity
When tested in accordance with section 5.3.4 of BS 8408:2005, no more than 3% of
the uncut edge cells shall be penetrated by water.
5(v)
Appearance after weathering
When exposed as required in section 5.4.5 of BS 8408:2005, the sheeting shall not
show significant cracking, scaling, pitting, blistering, edge lifting, delamination,
curling, shrinkage or expansion or other obvious defects.