Raman spectroscopy was used to analyze blue gel pen inks. Four groups of inks were distinguished based on their Raman spectra using both 514.5 nm and 830 nm lasers. The groups included inks containing pigment blue 15, pigment blue 15 and pigment violet 23, and pigment blue 15 analyzed against a database of ink spectra. Raman spectroscopy proved effective at discriminating inks based on their pigment components and matching to reference spectra in a database.

1. Raman spectroscopy of blue gel pen inks
Sarat Luandee
52312340
Williams David Mazzella ,Patrick Buzzini
Forensic Science International 152 (2005) 241–247

2. Topic
1. Raman spectroscopy
2. Blue gel pen inks
3. Materials and methods
4. Results
5. Conclusions

3. Raman spectroscopy
: !#$%
'()*+(+),-$.)

4. Raman spectroscopy
()*+ - .( /.0
- .( 123
- Homonuclear diatomics 15*6 N2
.8(9: - ;1 +2()*+ :=: *6?(@.( 6AB+6C98
- C*B+3+)()*+
- C*)* )+?D6?+1:)()*+
- ;1 +2()*+ :=:;+E68()C98

5. Blue gel pen inks
- (vehicle)
- (dyes and pigments)
- (Resin)
-

6. Materials and methods
6
1. 1?0@()*+ +??+
2. ?+9 (@ + ++D6?+33+)
D6 +33+)1+6(3
3. ?+1:)()*+ @6?9+F
4. ?+;1 +298) Raman spectroscopy
5. ?+9 (@ +/?*+ .( ?9+F
6. ?+I9B+ database

7. 1. 1?0@()*+ +??+ IB+66 55 ()*+
/)) 55 -
--* 0
---)
- --1

8. 2. ?+9 (@ + ++D6?+33+)D6 +33+)1+6(3
-2/)) 55 -
#/#$3 45) 5) #)
36 7* 19 *0

9. *)2 $)-9A4
):=28( A4 Lxerox business TCFP
#$0 stereo microscope
3. ?+1:)()*+ @6?9+F

10. 4. ?+;1 +298) Raman spectroscopy
Renishaw Raman RM 1000

11. wavelength
-514.5 nm : from an argon ion
: waverange 4000 and 200 cm-1
-830 nm : from a near infrared (NIR)
: waverange 4000 and 200 cm-1

12. standard pigments
-PB 15:1, Hostaperm Blau A2R, Hoechst
(a-copper–phthalocyanine).
- PB 15:2, Hostaperm Blau AFL, Hoechst
(a-copper–phthalocyanine)
-PB 15:3, Hostaperm Blau B2G, BASF
(b-copper–phthalocyanine).
-PB 15:4, Hostaperm Blau BFL, Hoechst
(b-copper–phthalocyanine).
- PV 23, Hostaperm Violett RL, Hoechst.

13. Pigment #*:$
1. pigment blue 15
class of phthalocyanines
2. pigment violet 23
class of the oxazines

14. 5. ?+9 (@ +/?*+ .( ?9+F
*1?0@()*+ ?9+F:=/?*+ ?6 IB+66 10 ()*+
1.:)6+??+3 @6?9+F
?+;1 +298) Raman spectroscopy

15. 6. ?+I9B+ database
U+6.8(V32W?+??+
*()*+
:=+@56;9 2 ()*+
*()*+
C*:=+@56;9 3 ()*+
1:)@1:)@()*+ ?@U+6.8(V3

16. Cross Matrix Dyes
Dong-A Dyes
Dong-A Dyes
Fila Dyes
Le Grip Twin Gel Dyes
Montex Dyes
Papemate (CAN) Dyes
Papermate (USA) Dyes
Parker Dyes
Pentel Energel (CAN) Dyes
Pentel Energel (USA) Dyes
Pilot G-1 Dyes
Pilot G-1 (CAN) Dyes
Pilot G-2 Dyes
Pilot G2 USA Dyes
Pilot SuperGel Dyes
Reynolds Dyes
Rotring Dyes
Stypen Dyes
List of gel pen inks analysed
X3?+9 (@ + ++D6?+33+)D6 +33+)1+6(3

17. Bic Intensity (CAN) Pigment
Bic Intensity (CH) Pigment
Brio Scatto Gel Pigment
Edding 2170 Pigment
Edding 2189 Pigment
Flair 250 Pigment
Focus II Pigment
Focus LX Pigment
Herlitz (Zebra) Pigment
Marvy Excel Pigment
Merangue Hi jell Pigment
Mondial LUS Pigment
Montex HY Power Pigment
Papermate (CH) Pigment
Pentel K 106 Pigment
Pentel K 118 Pigment
Pentel K 160 Pigment
Pentel K 227 (CH) Pigment
Pentel K 227 (USA) Pigment
Pentel KN 127 Pigment
Pilot G-Tec C4 Pigment
Pilot P500 Pigment
Sakura MED Pigment
Sakura XPGB (S) Pigment
Sakura XPGB (USA) Pigment
Sanford Gel RT Pigment
Sanford Refill RT Pigment
Sanford Uniball (CAN) Pigment
Schneider Pigment
Staples Pigment
Uniball Signo (CAN) Pigment
Uni-ball UM 1338 Pigment
Uniball UM 153 Pigment
Zebra Antique Pigment
Zebra JimnieGel Pigment
Zebra Sarasa Pigment
List of gel pen inks analysed

18. Raman spectra of the four groups obtained using the argon ion laser (514.5 nm).
X3?+;1 +298) Raman spectroscopy

20. Raman spectra of the four groups obtained using the NIR laser (830 nm)

22. Raman spectra of the four groups obtained using the argon ion laser (514.5 nm).
PB15 and PV 23
PB15
PV 23
PB15+1390 cm-1
4 samples
16 samples
15 samples
1 sample

23. Raman spectra of the four groups obtained using the NIR laser (830 nm)
PB15
PB15 and PV 23
PB15 and PV 23
21 samples
4 samples
11 samples

25. Discriminating power (DP)

26. Discriminating power (DP)
D = 1 – 1 ∑ xj (xj-1)
N(N-1)
D = index of discriminatory power
N = number of onrelated strains tested
S = number of different types
Xj = number of strains belong to the jth types

27. X3?+9 (@ +/?*+ .( ?9+F

28. - 9 (@+??+(619:)?6@6?9+F:=/?*+ ?6 10 ()*+
Y@*+ D28 1?12Z(6?6
- +??+*619:)?6 ):=28(19:)?6 [ZA(I+?*+ @;1E
Y@*+D28 1?12Z(6?6
- 1:)@1:)@()*+ I+?database ++@ ):=28( *6

29. Conclusions
-RS 2=)#3)3#*)-)5C*B+3+)()*+ /3910
- ++@1(?3?FE.( +??+:=: pigment C98
- ?+D58database ++@1(?3?FEC98 *+)/3910

31. D = 1 – 1 ∑ xj (xj-1)
N(N-1)
D = index of discriminatory power
N = number of onrelated strains tested
S = number of different types
Xj = number of strains belong to the jth types