申请人:Hainz Rudiger
公开号:US20110023754A1
公开(公告)日:2011-02-03
Pigment of formula wherein R
1
is CONR
4
R
5
or C(═NR
6
)NR
7
R
8
, R
2
, R
3
, R
4
and R
5
are each independently of the others H, C
1
-C
5
alkyl, or phenyl which is unsubstituted or substituted from 1 to 5 times by C
1
-C
5
alkyl or by halogen, R
6
is phenyl which is unsubstituted or substituted from 1 to 4 times by C
1
-C
5
alkyl or by halogen, R
7
is H or C
1
-C
5
alkyl, and R
8
is a direct bond or a carbonyl bridge to R
6
, which pigment consists of primary particles the average aspect ratio of which is from 4 to 1, preferably from 3.5 to 1, especially from 3 to 1, and for the ellipses equivalent to the contours of the primary particles on a two-dimensional electron microscopic image have an average numerical eccentricity ε of from 0 to 0.80, the numerical eccentricity ε being defined as (formula), wherein a is the semimajor axis and b is the semiminor axis of the equivalent ellipse. That pigment preferably has a narrow particle size distribution and is, as are analogous pigments, prepared by a novel process. The invention relates also to a process for the preparation of that pigment, wherein R
1
CH
2
CN or (formula) is dispersed in an acidic aqueous medium containing from 70 to 99% by weight water, preferably in the presence of a dispersant, and is reacted with solid (formula).
preferably
ɛ
=
a
2
-
b
2
a
该配方的颜料中,其中R1为CONR4R5或C(═NR6)NR7R8,R2、R3、R4和R5各自独立地为H、C1-C5烷基或苯基,该苯基未被取代或被C1-C5烷基或卤素取代1至5次,R6为未被取代或被C1-C5烷基或卤素取代1至4次的苯基,R7为H或C1-C5烷基,R8为与R6直接键合或具有一个羰基桥连接到R6,该颜料由平均长宽比为4:1的初级颗粒组成,优选为3.5:1,特别优选为3:1,对于等于二维电子显微图上初级颗粒轮廓的椭圆形状,其平均数离心率ε为0至0.80,其中数值离心率ε定义为(公式),其中a是等效椭圆的半长轴,b是半短轴。该颜料优选具有窄的粒径分布,并且与类似的颜料一样,通过一种新的工艺制备。该发明还涉及一种制备该颜料的方法,其中R1CH2CN或(公式)分散在含有70至99%重量水的酸性水介质中,优选在分散剂的存在下,并与固体(公式)反应。优选ɛ=a2-b2a。