Registration Dossier

Administrative data

Endpoint:
nanomaterial aspect ratio/shape
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2019
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
test procedure in accordance with national standard methods with acceptable restrictions

Data source

Reference
Reference Type:
other: unpublished study report
Title:
Unnamed
Year:
2019
Report date:
2019

Materials and methods

Principles of method if other than guideline:
Image analysis: manual image analysis according to REACH criteria (NanoDefine ParticleSizer)
Guidelines from NanoDefine are applied:
Method selection according to Gaillard et al., Nanoscale Adv., 2019, 1, 781
TEM image evaluation according to Verleysen et al., Materials 2019, 12, 2274; doi:10.3390/ma12142274
GLP compliance:
no
Type of method:
transmission electron microscopy
Details on methods and data evaluation:
Specimen preparation:
A few mg of the previously wobbled/shaken pigment powder was dispersed in distillated water in an ultrasonic bath. A droplet of the well dispersed and diluted pigment dispersion was transferred to a TEM-grid (Cu) coated with a polymer support film (Formvar®).

Test material

Constituent 1
Chemical structure
Reference substance name:
5-[(2,3-dihydro-6-methyl-2-oxo-1H-benzimidazol-5-yl)azo]barbituric acid
EC Number:
276-344-2
EC Name:
5-[(2,3-dihydro-6-methyl-2-oxo-1H-benzimidazol-5-yl)azo]barbituric acid
Cas Number:
72102-84-2
Molecular formula:
C12H10N6O4
IUPAC Name:
5-[(2,3-dihydro-6-methyl-2-oxo-1H-benzimidazol-5-yl)azo]barbituric acid
Test material form:
solid: nanoform

Data gathering

Instruments:
Zeiss EM910 100kV
Calibration:
no data
Reproducibility:
no data

Results and discussion

Shape description
Key result
Shape:
spherical
Remarks on result:
other: The material is assigned to the “spheroidal” shape category.
Aspect ratio
Key result
x Dimension:
1.7
St. dev.:
0.7
y Dimension:
1
Remarks on result:
other: median (D50)

Applicant's summary and conclusion

Conclusions:
The particles have a median aspect ratio of 1,7:1.
The shape is “spherical”.
The material is assigned to the “spheroidal” shape category.