1. A dispersion comprising metallic, metal oxide or metal precursor nanoparticles, a polymeric dispersant and an optional dispersion medium, the dispersant comprising an anchor group with affinity for the metallic, metal oxide or metal precursor nanoparticles that is chemically bonded to a polymeric backbone wherein the dispersant has a 95 wt % decomposition at a temperature below 300\xb0 C. as measured by Thermal Gravimetric Analysis, wherein the anchor group is according to Formula II, III, IV, or V,
wherein R3, R4, R7, R8, R9, R10, and R12 independently represent a halogen, an optionally substituted thiol, a hydroxyl, a carboxylic acid, an aldehyde, an ester, an amide, a primary amine, a secondary amine, a tertiary amine, an optionally substituted alkyl, aryl, aralkyl or alkylene group;
R7 and R8 can be optionally linked and form a ring structure;
R5, R6, and R11 represent independently a halogen, an optionally substituted thiol, a carboxylic acid, a primary amine, a secondary amine, a tertiary amine, an optionally substituted alkyl, aryl or aralkyl group;
X independently represents a \u2014N\u2014, a \u2014CH\u2014, or a \u2014C(CR13)\u2014 and where R13 represents a methyl, an optionally substituted alkyl, aryl or aralkyl group and where X can optionally be linked to R9 or R and form a ring structure; and
Y represents oxygen, sulfur, or \u2014NR14\u2014, wherein R14 represents a methyl, an optionally substituted alkyl, aryl or aralkyl group.
2. The dispersion according to claim 1, wherein the polymeric backbone of the dispersant is an aliphatic polyether backbone.
3. The dispersion according to claim 1, wherein the polymeric backbone is selected from
\u2014(CH2\u2014O)n\u2014
\u2014(CH2\u2014CH2\u2014O)n\u2014
\u2014(CH2\u2014CHCH3\u2014O)n\u2014
\u2014(CH2\u2014CH2\u2014CH2\u2014O)n\u2014
\u2014(CH2\u2014CH2\u2014CH2\u2014CH2\u2014O)n\u2014
\u2014(CH2\u2014CH2\u2014O\u2014CH2\u2014O)n\u2014
\u2014(CH2\u2014CH2\u2014CH2\u2014O\u2014CH2\u2014O)n\u2014
\u2014(CH2\u2014CH2\u2014CH2\u2014CH2\u2014CH2\u2014O)n\u2014
\u2014(CH2\u2014CH2\u2014CH2\u2014CH2\u2014CH2\u2014CH2\u2014O)n\u2014
\u2014(CH2\u2014CH2\u2014CH2\u2014CH2\u2014O\u2014CH2\u2014O)n\u2014
wherein n is an integer between 14 and 500.
4. The dispersion according to claim 1, wherein the polymeric backbone is according to Formula I,
wherein m is an integer between 1 and 500, o is an integer between 0 and 340, q is an integer between 0 and 250, p is an integer between 1 and 7,
m+o+q is an integer between 14 and 500,
R2 represents hydrogen, methyl or an optionally substituted alkyl group.
5. The dispersion according to claim 1, wherein the average numerical molecular weight of the polymeric dispersant is between 1500 and 6000 Da.
6. The dispersion according to claim 1, comprising at least 1 wt % of metallic, metal oxide or metal precursor nanoparticles.
7. A homogeneous paste prepared by evaporating substantially all of a dispersion medium of the dispersion as defined in claim 1 and comprising at least 75 wt % of metallic, metal oxide or metal precursor nanoparticles.
8. A method of preparing a dispersion as defined in claim 1 comprising dispersing metal, metal oxide or metal precursor particles in the presence of the polymeric dispersant in a dispersion medium.
9. The method of preparing a dispersion comprising metallic, metal oxide or metal precursor nanoparticles according to claim 8, wherein the dispersion medium is 1-methoxy-2-propanol, methanol, ethanol, isopropanol or a combination thereof.
10. A method of preparing a dispersion comprising metallic nanoparticles according to claim 1 by an in-situ reduction under mixing of a metal precursor, a metal oxide, a metal salt or a combination thereof, in the presence of a reducing agent, the polymeric dispersant and the dispersion medium.
11. A polymeric dispersant comprising an anchor group with affinity for metallic, metal oxide or metal precursor nanoparticles that is chemically bonded to a polymeric backbone and wherein the polymeric dispersant has a 95 wt % decomposition at a temperature below 300\xb0 C. as measured by Thermal Gravimetric Analysis,
wherein the polymeric backbone is according to Formula I,
wherein m is an integer between 1 and 500, o is an integer between 0 and 340, q is an integer between 0 and 250, p is an integer between 1 and 7,
m+o+q is an integer between 14 and 500, and
R2 represents hydrogen, a methyl or an optionally substituted alkyl group,
wherein the anchor group is according to Formula II, III, IV or V,
wherein R3, R4, R7, R8, R9, R10, and R12 independently represent a halogen, an optionally substituted thiol, a hydroxyl, a carboxylic acid, an aldehyde, an ester, an amide, a primary amine, a secondary amine, a tertiary amine, an optionally substituted alkyl, aryl, aralkyl or alkylene group;
R7 and R8 can be optionally linked and form a ring structure;
R5, R6, and R11 represent independently a halogen, an optionally substituted thiol, a carboxylic acid, a primary amine, a secondary amine, a tertiary amine, an optionally substituted alkyl, aryl or aralkyl group;
X independently represents a \u2014N\u2014, a \u2014CH\u2014, or a \u2014C(CR13)\u2014 and where R13 represents a methyl, an optionally substituted alkyl, aryl or aralkyl group and where X can optionally be linked to R9 or R10 and form a ring structure; and
Y represents oxygen, sulfur, or \u2014NR14\u2014, wherein R14 represents a methyl, an optionally substituted alkyl, aryl or aralkyl group.
12. A method of preparing the polymeric dispersant according to claim 11 by a reaction between:
90 to 99.4 mol % of a monomer represented by Formula VI, VII or VIII, or a combination thereof;
wherein R1 represents a (CH2)p unit with p is an integer between 1 and 7 and R2 represents hydrogen, a methyl or an optionally substituted alkyl group,
0.1 to 10 mol % of an anchor group according to Formulae II, III, IV, or V, or a combination thereof; and
0.1 to 0.5 mol % of a polymerization initiator selected from the group of a proton acid, a Lewis acid, an oxonium compound, or an anionic initiator selected from the group consisting of an alcoholate and an organometallic compound.
13. A printing fluid prepared from the dispersion defined in claim 1 and having a viscosity at jetting temperature between 5 and 20 mPa\xb7s.
14. A method of preparing a metallic layer or pattern comprising printing the dispersion according to claim 1 on a substrate followed by sintering at a temperature below 300\xb0 C.
15. A printing fluid prepared from the paste defined in claim 7 and having a viscosity at jetting temperature between 5 and 20 mPa\xb7s.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method comprising:
predicting a sign of an adaptive differential pulse code modulation (ADPCM) delta value of a signal; and
skewing an ADPCM encoding scheme based upon the predicted sign.
2. The method of claim 1 further comprising:
encoding the ADPCM delta value using the skewed ADPCM encoding scheme.
3. The method of claim 2 wherein the ADPCM encoding scheme is a three-bit encoding scheme skewed to provide four positive resolution levels, a zero level, and three negative resolution levels, and wherein the encoding is effected using the four positive resolution levels.
4. The method of claim 2 wherein the ADPCM encoding scheme is a three-bit encoding scheme skewed to provide five positive resolution levels, a zero level, and two negative resolution levels, and wherein the encoding is effected using the five positive resolution levels.
5. The method of claim 1 wherein the sign of the ADPCM delta value is predicted based upon a sign of one or more preceding delta values.
6. The method of claim 1 wherein the ADPCM encoding scheme is skewed with an asymmetry based upon a predicted frequency of the signal.
7. The method of claim 6 wherein the predicted frequency of the signal is determined by evaluating one or more characteristics of the signal.
8. The method of claim 7 wherein the one or more characteristics of the signal evaluated are selected from the group consisting of signal zero crossings, signal sign changes, signal slope changes, signal values, and combinations thereof.
9. A machine-readable medium having stored thereon a set of instructions which when executed cause a system to perform a method comprising:
predicting a sign of an adaptive differential pulse code modulation (ADPCM) delta value of a signal; and
skewing an ADPCM encoding scheme based upon the predicted sign.
10. The machine-readable medium of claim 9 further comprising:
encoding the ADPCM delta value using the skewed ADPCM encoding scheme.
11. The machine-readable medium of claim 10 wherein the ADPCM encoding scheme is a three-bit encoding scheme skewed to provide four positive resolution levels, a zero level, and three negative resolution levels, and wherein the encoding is effected using the four positive resolution levels.
12. The machine-readable medium of claim 10 wherein the ADPCM encoding scheme is a three-bit encoding scheme skewed to provide five positive resolution levels, a zero level, and two negative resolution levels, and wherein the encoding is effected using the five positive resolution levels.
13. The machine-readable medium of claim 9 wherein the sign of the ADPCM delta value is predicted based upon a sign of one or more preceding delta values.
14. The machine-readable medium of claim 9 wherein the ADPCM encoding scheme is skewed with an asymmetry based upon a predicted frequency of the signal.
15. The machine-readable medium of claim 14 wherein the predicted frequency of the signal is determined based upon one or more signal characteristics.
16. The machine-readable medium of claim 15 wherein the one or more characteristics of the signal evaluated are selected from the group consisting of signal zero crossings, signal sign changes, signal slope changes, signal values, and combinations thereof.
17. A system comprising:
a processor; and
a memory coupled to the processor, the memory having stored thereon one or more executable instructions, which when executed by the processor cause the processor to perform a method comprising:
predicting a sign of an adaptive differential pulse code modulation (ADPCM) delta value of a signal; and
skewing an ADPCM encoding scheme based upon the predicted sign.
18. The system of claim 17 wherein the method further comprises:
encoding the ADPCM delta value using the skewed ADPCM encoding scheme.
19. The system of claim 18 wherein the ADPCM encoding scheme is a three-bit encoding scheme skewed to provide four positive resolution levels, a zero level, and three negative resolution levels, and wherein the encoding is effected using the four positive resolution levels.
20. The system of claim 18 wherein the ADPCM encoding scheme is a three-bit encoding scheme skewed to provide five positive resolution levels, a zero level, and two negative resolution levels, and wherein the encoding is effected using the five positive resolution levels.
21. The system of claim 17 wherein the sign of the ADPCM delta value is predicted based upon a sign of one or more preceding delta values.
22. The system of claim 17 wherein the ADPCM encoding scheme is skewed with an asymmetry based upon a predicted frequency of the signal.
23. The system of claim 22 wherein the predicted frequency of the signal is determined based upon one or more signal characteristics.
24. The system of claim 23 wherein the one or more characteristics of the signal evaluated are selected from the group consisting of signal zero crossings, signal sign changes, signal slope changes, signal values, and combinations thereof.