1. A coating composition, comprising:
a coating material; and
a matting agent, comprising:
a surface-modified precipitated silica having a polymer on a surface thereof;
wherein said surface-modified precipitated silica improves a transmission of a clear coating material, having a refractive index of nD20=1.4492 and containing 5% by weight of said surface-modified precipitated silica, by at least 20%, in comparison to said clear coating material containing 5% by weight of a reference precipitated silica surface treated with a polyethylene wax;
wherein the polymer is a polyorganosiloxane having the following structure:
wherein
Y=\u2014OH, \u2014OR or
Y=H5C2\u2014O\u2014(C2H4O)m\u2014, H7C3\u2014O\u2014(C3H6O)m\u2014 or
R=alkyl,
R2=alkyl,
R3=alkyl,
a=0-100, b is >=1 to 100, c=0-100, d is >=1 to 100,
m=0-100 and k=0-100; or
wherein the polymer is a polyorganosiloxane having the following structure:
wherein
R1 is a methyl radical or
and a sum of the units a=0 to 100, the sum of the units b=0 to 15, the ratio of methyl to alkoxy radicals for the radicals R1 being less than 50:1 and b being \u22671 if =0, and a\u22675 if b=0.
2. The coating composition of claim 1, wherein said surface-modified precipitated silica satisfies the following requirements:
a particle distribution d50 is 1-50 \u03bcm;
an oil absorption DBP is 100-600 g100 g; and
a C content is 1-20%.
3. The coating composition of claim 1, wherein said surface-modified precipitated silica has a Sears number V2<25 ml5 g.
4. The coating composition of claim 2, wherein the particle distribution d50 of said surface-modified precipitated silica is 1-40 \u03bcm.
5. The coating composition of claim 2, wherein the oil absorption DBP of said surface-modified precipitated silica is 200-500 g100 g.
6. The coating composition of claim 2, wherein the C content of said surface-modified precipitated silica is 1-10%.
7. The coating composition of claim 1, wherein said surface-modified precipitated silica improves the transmission of said clear coating material containing 5% by weight of said surface-modified precipitated silica, by at least 25%.
8. The coating composition of claim 1, wherein said surface-modified precipitated silica improves the transmission of said clear coating material containing 5% by weight of said surface-modified precipitated silica, by at least 30%.
9. The coating composition of claim 1, wherein an uncoated silica of said surface-modified precipitated silica and said reference precipitated silica are the same; and wherein said reference precipitated silica is coated with a polyethylene wax.
10. The coating composition of claim 1, wherein the polymer is a polyorganosiloxane having the following structure:
wherein
Y=\u2014OH, \u2014OR or
Y=H5C2\u2014O\u2014(C2H4O)m\u2014, H7C3\u2014O\u2014(C3H6O)m\u2014 or
R=alkyl,
R2=alkyl,
R3=alkyl,
a=0-100, b is >=1 to 100, c=0-100, d is >=1 to 100,
m=0-100 and k=0-100.
11. The coating composition of claim 1, wherein the polymer is a polyorganosiloxane having the following structure:
wherein
R1 is a methyl radical or
and a sum of the units a=0 to 100, the sum of the units b=0 to 15, the ratio of methyl to alkoxy radicals for the radicals R1 being less than 50:1 and b being \u22671 if a=0, and a>5 if b=0.
12. A lacquer, comprising:
a lacquer formulation; and
a surface-modified precipitated silica having a polymer on a surface thereof, wherein said surface-modified precipitated silica improves a transmission of a clear coating material, having a refractive index of nD20=1.4492 and containing 5% by weight of said silica, by at least 20%, in comparison to said clear coating material containing 5% by weight of a reference precipitated silica treated with a polyethylene wax;
wherein the polymer is a polyorganosiloxane having the following structure:
wherein
Y=\u2014OH, \u2014OR or
Y=H5C2\u2014O\u2014(C2H4O)m\u2014, H7C3\u2014O\u2014(C3H6O)m\u2014 or
R=alkyl,
R2=alkyl,
R3=alky,
a=0-100, b is >=1 to 100, c=0-100, d is >=1 to 100,
m=0-100 and k=0-100; or
wherein the polymer is a polyorganosiloxane having the following structure:
wherein
R1 is a methyl radical or
and a sum of the units a=0 to 100, the sum of the units b=0 to 15, the ratio of methly to alkoxy radicals for the radicals R1 being less than 50:1 and b being \u22671 if a=0, and a\u22675 if b=0.
13. The lacquer of claim 12, wherein the surface-modified silica satisfies the following requirement:
a particle distribution d50 is 1-50 \u03bcm,
an oil absorption DBP is 100-600 g100 g, and
a C content is 1-20%.
14. The lacquer of claim 12, wherein the surface-modified silica has a Sears number V2<25 ml5 g.
15. The lacquer of claim 14, wherein the surface-modified silica has a particle distribution d50 of from 1 to 40 \u03bcm.
16. The lacquer of claim 14, wherein the surface-modified silica has an oil absorption DBP of from 200 to 500 g100 g.
17. The lacquer of claim 14, wherein the surface-modified silica has a C content of from 1 to 10%.
18. The lacquer of claim 12, wherein the surface-modified silica improves the transmission of said clear coating material containing 5% by weight of this surface-modified precipitated silica, by at least 25%.
19. The lacquer of claim 12, wherein the surface-modified silica improves the transmission of said clear coating material containing 5% by weight of this surface-modified precipitated silica, by at least 30%.
20. The lacquer of claim 12, wherein a uncoated silica of said surface-modified silica and said surface modified-silica are the same; and wherein said reference silica is coated with a polyethylene wax.
21. The lacquer of claim 12, wherein the polymer used to surface modify the said surface-modified silica is a polyorganosiloxane or a modified polyorganosiloxane.
22. The lacquer of claim 12, wherein the polymer is a polyorganosiloxane having the following general structure:
wherein
Y=\u2014OH, \u2014OR or
Y=H5C2\u2014O\u2014(C2H4O)m\u2014, H17C3\u2014O\u2014(C3H6O)m\u2014 or
R=alkyl, in particular methyl or ethyl,
R2=alkyl,
R3=alkyl,
a=0-100, b is >=1 to 100, c=0-100, d is >=1 to 100,
m=0-100 and k=0-100.
23. The lacquer of claim 21, wherein the polymer is a polyorganosiloxane having the following general structure:
where
R1 is a methyl radical or
and a sum of the units a=0 to 100, the sum of the units b=0 to 15, the ratio of methyl to alkoxy radicals for the radicals R1 being less than 50:1 and b being \u22671 if a=0, and a\u22675 if b=0.
24. A process for preparing a lacquer according to claim 12, comprising:
obtaining a surface-modified, hydrophobicized precipitated silica by
a) precipitating an alkali metal silicate solution with an acidifier under weak acidic to alkaline conditions,
b) further adding an acidifier to set a pH of from 7 to 2, to give a silica suspension,
c) isolating the precipitated solid by filtration, thereby obtaining a precipitated silica, and
d) drying the precipitated silica such that a residual moisture content is less than 10%,
e) treating the silica suspension or the precipitated silica with a polymer to obtain said surface-modified precipitated silica, the amount and the nature of the polymer being chosen such that the modified precipitated silica improves a transmission of a clear coating material, having a refractive index of nD20=1.4492 and containing 5% by weight of this modified precipitated silica, by at least 20%, in comparison to said clear coatings material containing 5% by weight of a reference precipitated silica treated with a polyethylene wax,
and
adding said surface-modified, hydrophobicized precipitated silica to said lacquer formulation.
25. The process as claimed in claim 24, wherein 0.5-30% by weight of a polyorganosiloxan or a modified polyorganosiloxane is added to the silica suspension adjusted in step b) to a pH of 7-2.
26. The process of claim 24, wherein the treatment in step e) is carried out for 1 to 30 minutes and with stirring.
27. The process of claim 24, wherein step e) is carried out in a silica suspension; and wherein the temperature of the silica suspension in step e) is 20-100\xb0 C.
28. The process as claimed in claim 24, wherein the precipitated silica isolated by filtration in accordance with step c) and optionally washed with deionized water is resuspended with water or sulfuric acid or with a mixture of water and sulfuric acid; and subsequently in step e) 0.5-30% by weight of a polyorganosiloxane or a modified polyorganosiloxane is added to the silica suspension and the resulting suspension is dried, to obtain said surface-modified silica.
29. The process of claim 27, wherein the drying after step e) takes place such that the product has a residual moisture content of less than 10%.
30. The process of claim 27, wherein the temperature of the silica suspension in step e) is 20-100\xb0 C.
31. The process as claimed in claim 24, wherein after step d) 0.5-30% by weight of polyorganosiloxane or a modified polyorganosiloxane is added in step e) to the silica and the two arc intimately mixed.
32. The process of claim 31, wherein the addition in step c) is carried out with a duration of from 0 to 120 minutes and with mixing.
33. The process of claim 32 wherein the silica and the polyorganosiloxane or the modified polyorganosiloxane are mixed for 0-2 h more.
34. The process of claim 31, wherein the temperature of the mixture in step e) is 20-150\xb0 C.
35. The process of claim 24, wherein the polymer is a polyorganosiloxane or a modified polyorganosiloxane.
36. The process of claim 35, wherein the polymer is a polyorganosiloxane having the following general structure:
wherein
Y=\u2014OH, \u2014OR or
Y=H5C2\u2014O\u2014(C2H4O)m\u2014, H7C3\u2014O\u2014(C3H6O)m\u2014 or
R=alkyl, in particular methyl or ethyl,
R2=alkyl,
R3=alkyl,
a=0-100, b is >=1 to 100, c=0-100, d is >=1 to 100,
m=0-100 and k=0-100.
37. The process of claim 35, wherein the polymer is a polyorganosiloxane having the following general structure:
where
R1 is a methyl radical or
and the sum of the units a=0 to 100, the sum of the units b=0 to 15, the ratio of methyl to alkoxy radicals for the radicals R1 being less than 50:1 and b being \u22671 if a=0, and a\u22675 if b=0.
38. The process of one of claim 24, further comprising f) grinding after the surface-modified precipitated silica has been dried.
39. The process of claim 38, wherein after the surface-modified silica has been dried or after or during the grinding in step f) particles having a diameter of more than 50 \u03bcm are separated off.
40. The coating, composition of claim 1, wherein the surface-modified silica imparts improved transmission in relation to a reference precipitated silica treated with polyethylene wax, said reference precipitated silica having the following properties:
ACEMATT\u2009\xae
Features and test methods
Units
OK 412
Loss on drying
%
6
2 h at 105\xb0 C.
in accordance with DIN EN ISO 787-2
Loss on ignition based on dried substance
%
13
2 h at 1000\xb0 C.
in accordance with DIN EN ISQ 3262-1
pH
\u2014
6
5% in water
in accordance with DIN EN ISO 787-0
Sulfate content as SO4
%
1
IR spectroscopy
Degussa method
Particle size
\u03bcm
mean value (TEM)
3
D50 value (laser diffraction)
6.0
Surface treatment
Organic
Tapped density
gl
130
unsieved
in accordance with DIN EN ISO 787-11
Density
gcm3
1.9
in accordance with DIN EN ISO 787-10
Oil number
g100 g
220
in accordance with DIN EN ISO 787-5
SiO2 content based on ignited substance
%
98
in accordance with DIN EN ISO 3262-19.
41. The lacquer of claim 12, wherein the surface-modified silica imparts improved transmission in relation to a reference precipitated silica treated with polyethylene wax, said reference precipitated silica having the following properties:
ACEMATT\u2009\xae
Features and test methods
Units
OK 412
Loss on drying
%
6
2 h at 105\xb0 C.
in accordance with DIN EN ISO 787-2
Loss on ignition based on dried substance
%
13
2 h at 1000\xb0 C.
in accordance with DIN EN ISQ 3262-1
pH
\u2014
6
5% in water
in accordance with DIN EN ISO 787-0
Sulfate content as SO4
%
1
IR spectroscopy
Degussa method
Particle size
\u03bcm
mean value (TEM)
3
D50 value (laser diffraction)
6.0
Surface treatment
Organic
Tapped density
gl
130
unsieved
in accordance with DIN EN ISO 787-11
Density
gcm3
1.9
in accordance with DIN EN ISO 787-10
Oil number
g100 g
220
in accordance with DIN EN ISO 787-5
SiO2 content based on ignited substance
%
98
in accordance with DIN EN ISO 3262-19.
42. The coating composition of claim 1, wherein said coating material is a clear coating material.
The claims below are in addition to those above.
All refrences to claims which appear below refer to the numbering after this setence.
1. A pivot pin structure comprising an axis and an assembling section disposed on a surface of the pivot pin, on the assembling section being disposed multiple ridge sections and valley sections non-parallel to the axis, the ridge sections and valley sections being arranged on the assembling section.
2. The pivot pin structure as claimed in claim 1, wherein the ridge sections and valley sections are formed in a cross-sectional direction of the pivot pin approximately normal to the axis of the pivot pin and continuously arranged on the surface of the pivot pin.
3. The pivot pin structure as claimed in claim 1, wherein the ridge sections are annularly disposed on the surface of the pivot pin in the form of a thread structure.
4. The pivot pin structure as claimed in claim 1, wherein the pivot pin has a first end and a second end, the first end being adjacent to the assembling section, the first end having a cross-sectional width slightly smaller than that of the assembling section.
5. The pivot pin structure as claimed in claim 4, wherein an embossed section is disposed on the pivot pin in adjacency to the second end thereof.
6. The pivot pin structure as claimed in claim 1, wherein the ridge sections are arranged in parallel to each other.
7. The pivot pin structure as claimed in claim 1, wherein at least one depression is formed on the pivot pin.
8. The pivot pin structure as claimed in claim 7, wherein the depression has the form of a dent with a plane face.
9. The pivot pin structure as claimed in claim 8, wherein the plane face of the dent has a height lower than that of outer surface of the pivot pin.
10. The pivot pin structure as claimed in claim 1, wherein an embossed section is disposed on the pivot pin, at least one depression being formed at a second end of the pivot pin in adjacency to the embossed section opposite to the assembling section.
11. The pivot pin structure as claimed in claim 10, wherein the depression has the form of a dent with a plane face.
12. The pivot pin structure as claimed in claim 11, wherein the plane face of the dent has a height lower than that of outer surface of the pivot pin.
13. The pivot pin structure as claimed in claim 7, wherein the depression is symmetrically formed on the pivot pin.
14. The pivot pin structure as claimed in claim 10, wherein the depression is symmetrically formed on the pivot pin.
15. The pivot pin structure as claimed in claim 1, wherein the ridge sections are discontinuously disposed on the assembling section of the pivot pin.
16. The pivot pin structure as claimed in claim 1, wherein the pivot pin has the form of a pole body.
17. The pivot pin structure as claimed in claim 1, wherein the assembling section is assembled with a bridge member in the form of a board body, the bridge member having a pivot section assembled with the assembling section of the pivot pin.
18. The pivot pin structure as claimed in claim 1, wherein an embossed section is disposed on the pivot pin in adjacency to the assembling section.
19. The pivot pin structure as claimed in claim 1, wherein an embossed section is disposed on the pivot pin and assembled with a bridge member.
20. The pivot pin structure as claimed in claim 17, wherein the bridge member is fixedly mounted on a display screen of an electronic device.
21. The pivot pin structure as claimed in claim 19, wherein the bridge member is fixedly mounted on an electronic device.
22. The pivot pin structure as claimed in claim 15, wherein the ridge sections are disconnectedly disposed on the surface of the pivot pin segment by segment.
23. The pivot pin structure as claimed in claim 1, wherein a lubricant is reserved in the valley sections.
24. The pivot pin structure as claimed in claim 1, wherein the ridge sections are continuously arranged on the surface of the pivot pin.
25. The pivot pin structure as claimed in claim 1, wherein the ridge sections and valley sections are formed in a cross-sectional direction of the pivot pin normal to the axis of the pivot pin and continuously arranged on the surface of the pivot pin.
26. The pivot pin structure as claimed in claim 1, wherein the ridge sections are independent annular raised stripes in parallel to each other.
27. The pivot pin structure as claimed in claim 1, wherein the valley sections are independent annular recessed stripes in parallel to each other.