A coating liquid for forming a transparent topcoat, without requiring a hardening or fixing process that uses heating or UV radiation. The coating liquid imparts light resistance, water resistance, fixation, and glossiness to recordings. Also, a recording method using the coating liquid, and recordings produced thereby. The liquid, which is applied to recorded images, contains at least water, fine polymer particles, and a penetrating agent, preferably a penetrating agent selected acetylene glycol surfactants, acetylene alcohol surfactants, glycol ethers, and 1,2-alkylene glycols. Also, an image recording method for forming an even, transparent coating layer by spraying the coating liquid during an ink jet recording process, as well as recordings produced thereby.

1. Field of the Invention
This invention relates to a coating liquid used in methods for coating recorded images, to an image recording method using that coating liquid, and to a recordings recorded therewith.
2. Description of the Related Art
Conventionally, the method of coating a recorded image with a laminate film is practiced as a method for protecting the recorded image and enhancing the bond between the recorded image and the base material. With this method, however, because separate process steps are required for supplying the laminate film, coating, and pressure application and the like, the apparatus itself becomes complex. With further innovations needed to effect suitable coatings, in Japanese Patent Application Laid-Open No. S59-104974/1984 (published), an apparatus is proposed for effecting good and suitable laminate coatings by the new addition, to the process, of an apparatus for detecting laminate film layer displacement. With this, however, the apparatus becomes even larger and more complex.
Ink jet recording, on the other hand, is a method wherewith text or graphics are recorded on the surface of a recording medium by ejecting small droplets of ink from very small nozzles. The ink jet recording procedures being implemented in practice include a method wherewith electrical signals are converted to mechanical signals using an electrostriction transducer, and ink stored in a nozzle head portion is discharged intermittently and text or symbols are recorded on the surface of a recording medium, and a method wherewith a part extremely close to the portion ejecting the ink stored in the nozzle head portion is rapidly heated to generate bubbles, intermittent ejection is effected by the cubical expansion of those bubbles, and text or symbols are recorded on the surface of a recording medium.
The recording liquids used in ink jet recording are mostly water-based in the interest of safety and recording properties, with water soluble dyes frequently used in the coloring agents, as a result of which these suffer the shortcoming of exhibiting inferior light resistance and water resistance. For that reason, various studies have been done on the use of pigments for the coloring agents with the object of gaining light resistance and water resistance in the recordings. With conventional methods, however, the fixation of the pigments to the recording medium is inadequate, which results in problems such as the paper smudging when rubbed with a finger, or a recorded portion becoming unsightly if the recording is marked with a so-called magic marker. Another problem therewith is inadequate glossiness.
As a separate measure, providing a protective coating layer to recordings recorded with ink jet recording procedures has been proposed for some time as a method for improving water resistance, fixation, and glossiness. In Japanese Patent Application Laid-Open No. S62-101482/1907 (published), for example, a method for fusion-transferring a thermally fusing coating agent onto a recorded image is investigated as a method for imparting water resistance to recordings colored with water soluble dye inks. In Japanese Patent Application Laid-Open No. H1-141782/1989 (published) and Japanese Patent Application Laid-Open No. H2-80279/1990 (published), a method is proposed for applying a liquid containing an isocyanate compound to a recorded image, and hardening it, to form a protective coating layer. In Japanese Patent Application Laid-Open No. H6-115066/1994 (published), a method in proposed wherewith high-quality recordings exhibiting outstanding bonding can be effected by forming a transparent topcoat layer after recording with an ink jet recording procedure on an ink absorption layer. And in Japanese Patent Application Laid-Open No. H9-262971/1997 (published), a printer is proposed wherewith, by spraying and fixing a laminate agent for laminating the recorded surface of a recording medium, recordings are obtained which can stand up under outdoor use. When such methods are used, however, the laminating apparatus itself is complex, or a hardening and fixing process using heat or UV radiation is required when forming the topcoat layer, or a separate process step is required for applying the film under pressure.
From the perspective of recording light resistance and water resistance, moreover, when a pigment like carbon black or the like is used for the colorant, dispersion in the ink is poor, clogging occurs, and pigment agglomeration occurs during storage, wherefore various kinds of dispersants have been studied. However, when these various dispersants such, for example, as resin dispersants, are merely added, those dispersants induce dispersion by adsorbing to the surface of the pigment particles, but the dispersants become detached from the surface of the pigment particles due to some causative factor or other, wherefore satisfactory dispersing effects have not been obtained. In cases where penetrating agents are added into the ink composition to impart a strong penetrating effect in order to increase the recorded image drying speed, in particular, dispersion stability sometimes deteriorates even more, a phenomenon thought to be caused by dispersant detachment being thereby promoted.
Thereupon, so-called self-dispersing surface-treated pigments (hereinafter called xe2x80x9csurface-treated pigmentsxe2x80x9d) have been proposed which improve pigment dispersion by subjecting the pigment particles to a surface treatment and thereby make it possible to disperse and/or dissolve the pigment particles in water without a dispersant. In Japanese Patent Application Laid-Open No. H10-195360/1998 (published) and Japanese Patent Application Laid-Open No. H10 330665/1998 (published), for example, self-dispersing carbon black is disclosed wherein a hydrophilic group such as the carboxyl group, carbonyl group, sulfone group, or hydroxyl group is bonded to the surface of the carbon black, either directly or with another atom group intervening. In Japanese Patent Application Laid-Open No. H8-3498/1996 (published), Japanese Patent Application Laid-Open No. H10-195331/1998 (published), and Japanese Patent Application Laid-Open No. H10-237349/1998 (published), for example, subjecting the surface of carbon black to an oxidation treatment to improve dispersion properties is proposed. And in Japanese Patent Application Laid-Open No. H8-283598/1996 (published), Japanese Patent Application laid-Open No. H10-110110/1998 (published), and Japanese Patent Application Laid-Open No. H10-110111/1998 (published), for example, surface-treated pigments are proposed wherein sulfone groups are inducted to the surfaces of organic pigments.
By using such surface-treated pigments as these in inks, it is possible to reduce the contained quantities of dispersants such as the resin dispersants conventionally used, or to avoid using such altogether. As a consequence, the solid matter content in ink compositions can be reduced, wherefore the viscosity of ink compositions can be lowered, the occurrence of clogging suppressed, and limitations on additives relaxed. Thus it is known that surfactants can be added to make fast-drying inks that penetrate faster into the recording medium, that the pigment content can be increased by the measure that the dispersant content can be reduced, and that, therefore, high image quality can be achieved with enhanced coloration.
Nevertheless, although it is possible to raise the image density on the recording medium and obtain high picture quality by increasing the pigment content in inks, new problems have arisen in that fixation or rubbing resistance deteriorates. Such decline in fixation and/or rubbing resistance is particularly conspicuous in glossy recording mediums having smooth surfaces.
Thereupon, an object of the present invention is to provide a coating liquid that does not require hardening or fixing processes using heat or UV radiation or the like, and also a recording method that, by coating that coating liquid with an ink jet recording procedure, imparts recording fastness in terms of light resistance, water resistance, and fixation, etc., and good image quality with outstanding glossiness, together with recordings recorded thereby.
Another object of the present invention is to provide a recording method wherein that coating liquid is used, wherewith, by using a surface-treated pigment as the pigment, recording can be performed with high image density and high picture quality, exhibiting rapid drying in addition to the proportion noted above, and wherewith fixation and rubbing resistance can be improved, together with recordings recorded thereby.
The inventors, as a result of intense investigations in an effort to resolve the problems noted in the foregoing, discovered that by controlling the penetrability of the coating liquid, recorded images are dried and fixed without requiring processes such as heating or hardening after coating on the coating liquid, and that recorded images exhibiting outstanding light resistance, water resistance, fixation, and image glossiness are thereby obtained, and thus have come to propose the present invention.
The present invention, specifically, is a coating liquid for application to recorded images containing at least water, fine polymer particles, and a penetrating agent. By providing this coating liquid, an object or objects noted earlier are attained.
The present invention also provides the coating liquid noted above wherein the surface tension in that coating liquid at 20xc2x0 C. is 40 mN/m.
The present invention is the coating liquid described above, wherein the penetrating agent is one or more substances selected from a group consisting of an acetylene glycol surfactant, an acetylene alcohol surfactant, a glycol ether, and a 1,2-alkylene glycol.
The present invention also provides the coating liquid described above, wherein the penetrating agent is an acetylene glycol surfactant and/or an acetylene alcohol surfactant, such acetylene glycol surfactant is one to which on average 30 or fewer ethylene oxy groups and/or propylene oxy groups are added to 2,4,7,9-tetramethyl-5-decine-4,7-diol, 3,6-dimetyl-4-octine-3,6-diol, or 2,4,7,9-tetramethyl-5-decine-4,7-diol, 3,6-dimethyl-4-octine-3,6-diol, and such acetylene alcohol surfactant is one to which on average 30 or fewer ethylene oxy groups and/or propylene oxy groups are added to 2,4-dimethyl-5-hexine-3-ol or 2,4-dimethyl-5-hexine-3-ol.
The present invention also provides the coating liquid described above, wherein the penetrating agent is a glycol ether, and that glycol ether is ethylene glycol mono(alkyl having 4 to 8 carbons) ether, triethylene glycol mono(alkyl having 4 to 8 carbons) ether, propylene glycol mono(alkyl having 3 to 6 carbons), or dipropylene glycol mono(alkyl having 3 to 6 carbons) ether.
The present invention also provides the coating liquid described above, wherein the penetrating agent is a 1,2-alkylene glycol, and that 1,2-alkylene glycol is a 1,2-(alkyl having 4 to 10 carbons) diol.
The present invention also provides the coating liquid described above, wherein the amount of the fine polymer particles contained is within a range of 1 to 40 wt. %.
The present invention also provides the coating liquid described above, wherein the minimum film formation temperature for the fine polymer particles is room temperature.
The present invention also provides the coating liquid described above, wherein the fine polymer particles are used as an aqueous emulsion configured only of a resin or resins having an acid value of 100 or less.
The present invention also provides the coating liquid described above, wherein the penetrating agent is an ethylene glycol surfactant and/or acetylene alcohol surfactant contained in an amount of 0.1 to 5.0 wt. %.
The present invention also provides the coating liquid described above, wherein the penetrating agent is a glycol ether contained in an amount of 0.5 to 30 wt. %.
The present invention also provides the coating liquid described above, wherein the penetrating agent is a 1,2-acetylene glycol contained in an amount of 0.5 to 30 wt. %.
The present invention also provides the coating liquid described above, containing at least one substance having the structure represented in formula (I) below.
R-EOn-POm-Xxe2x80x83xe2x80x83(I)
(where R represents an alkyl group having 1 to 12 carbons, the structure whereof may be either a straight chain or branching; X represents xe2x80x94H or xe2x80x94SO3M (where M is a counter ion that is hydrogen ion, alkaline metal ion, ammonium ion, or organic ammonium ion); EO represents an ethylene oxy group; PO represents a propylene oxy group; and n and m are repeating units, indicating mean values in one of the substances expressed in formula (I). EO and PO indicate presence in the molecule, with the order thereof being irrelevant.)
The present invention also provides the coating liquid described above, wherein R indicated in formula (I) above is an alkyl group having 4 to 10 carbons.
The present invention also provides the coating liquid described above, wherein the substance expressed in formula (I) above is one wherein R is a butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, or decyl group.
The present invention also provides the coating liquid described above, wherein the substance expressed in formula (I) above has as its main component at least one substance expressed in formula (I) wherein R is a butyl group selected from among the n-butyl, isobutyl, and t-butyl groups, or has as its main component at least one substance expressed in formula (I) wherein R is a pentyl group selected from among the n-pentyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is a hexyl group selected from among the n-hexyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is a heptyl group selected from among the n-heptyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is an octyl group selected from among the n-octyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is a nonyl group selected from among the n-nonyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is a decyl group selected from among the n-decyl group and other isomers.
The present invention also provides the coating liquid described above, wherein the substance expressed in formula (I) above is one wherein n is 0 to 10, and m is 1 to 5.
The present invention also provides the coating liquid described above, wherein the substance expressed in formula (I) above has an average molecular weight of 2,000 or less.
The present invention also provides the coating liquid described above, wherein the substance expressed in formula (I) above is contained in an amount of 0.5 to 30 wt. %.
The present invention also attains an object or objects noted earlier by providing an image recording method wherein the coating liquid described above is discharged onto at least the image portion of a recording medium using an ink jet head to form a coating.
The present invention also provides the image recording method described above, wherein the image to which the coat is applied was formed by discharging an ink composition onto a recording medium using an ink jet head.
The present invention also provides the image recording method described above, wherein the ink composition contains at least water, a colorant, and a penetrating agent.
The present invention also provides the image recording method described above wherein the colorant is a dye.
The present invention also provides the image recording method described above wherein the colorant is a pigment.
The present invention also provides the image recording method described above wherein the pigment is made one that is capable of being dispersed and/or dissolved in water by a dispersant.
The present invention also provides the image recording method described above wherein the pigment is surface-treated so that at least one of the functional groups represented below, or salt thereof, is bonded either directly or with a polyvalent group intervening, to the surface thereof, and is made capable of being dispersed and/or dissolved in water without a dispersant;
xe2x80x94OM, xe2x80x94COOM, xe2x80x94COxe2x80x94, xe2x80x94SO3M, xe2x80x94SO2NH2, xe2x80x94RSO2M, xe2x80x94PO3HM, xe2x80x94PO3M2, xe2x80x94SO2NHCOR, xe2x80x94NH3, xe2x80x94NR3 (where M is a hydrogen atom, alkaline metal, ammonium, or organic ammonium, and R is an alkyl group having 1 to 12 carbons, a phenyl group that may have a substituent group, or a naphthyl group that may have a substituent group).
The image recording method described above, wherein the polyvalent group is an alkyl group, a phenyl group that may have a substituent group, or a naphthyl group that may have a substituent group, having 1 to 12 carbons.
The present invention also provides the image recording method described above wherein the pigment is surface treated with a treatment agent containing sulfur so that SO3M and/or xe2x80x94RSO2M (where M is a counter ion that is a hydrogen ion, alkaline metal ion, an ammonium ion, or an organic ammonium ion) is chemically bonded to the surface of the particles thereof, and made capable of dispersing and/or dissolving in water.
The present invention also provides the image recording method described above, wherein the liquid in which the surface-treated pigment is dispersed exhibits a zeta potential having an absolute value of 30 mv or greater at 20xc2x0 C. and pH 8 to 9.
The present invention also provides the image recording method described above wherein the surface tension of the ink composition at 20 C. is 40 mN/m or less.
The present invention also provides the image recording method described above wherein the penetrating agent is one or more substance selected from among a group comprising acetylene glycol surfactants, acetylene alcohol surfactants, glycol ethers, and 1,2-alkylene glycols.
The present invention also provides the image recording method described above wherein the penetrating agent is an acetylene glycol surfactant and/or an acetylene alcohol surfactant, such acetylene glycol surfactant is one to which on average 30 or fewer ethylene oxy groups and/or propylene oxy groups are added to 2,4,7,9-tetramethyl-5-decine-4,7-diol, 3,6-dimetyl 4-octine-3,6-diol, or 2,4,7,9-tetramethyl-5-decine-4,7-diol, 3,6-dimethyl-4-octine-3,6-diol, and such acetylene alcohol surfactant is one to which on average 30 or fewer ethylene oxy groups and/or propylene oxy groups are added to 2,4-dimethyl-5-hexine-3-ol or 2,4-dimethyl-5-hexine-3-ol.
The present invention also provides the image recording method described above, wherein the penetrating agent is a glycol ether, and that glycol ether is ethylene glycol mono(alkyl having 4 to 8 carbons) ether, triethylene glycol mono(alkyl having 4 to 8 carbons) ether, propylene glycol mono(alkyl having 3 to 6 carbons), or dipropylene glycol mono(alkyl having 3 to 6 carbons) ether.
The present invention also provides the image recording method described above, wherein the penetrating agent is a 1,2-alkylene glycol, and that 1,2-alkylene glycol is a 1,2-(alkyl having 4 to 10 carbons) diol.
The present invention also provides the image recording method described above wherein the penetrating agent is an acetylene glycol surfactant of acetylene alcohol surfactant the contained amount whereof is 0.1 to 3.0 wt. %.
The present invention also provides the image recording method described above wherein the penetrating agent is a glycol ether, the contained amount whereof is 0.5 to 30 wt. %.
The present invention also provides the image recording method described above wherein the penetrating agent is a 1,2-alkylene glycol the contained amount whereof is 0.5 to 30 wt. %.
The present invention also provides the image recording method described above wherein at least one substance having the structure represented by formula (I) below is contained in the ink composition:
R-EOn-POm-Xxe2x80x83xe2x80x83(I)
(where R is an alkyl group having 1 to 12 carbons, the structure whereof is a straight chain or branched structure, X is xe2x80x94H or SO3M (where M is a counter ion that is a hydrogen ion, alkaline metal ion, ammonium ion, or organic ammonium ion), EO is an ethylene oxy group, PO is a propylene oxy group, and n and m are repeating units, representing mean values in one of the substances expressed in formula (I). EO and PO indicate presence in the molecule, with the order thereof being irrelevant.)
The present invention also provides the image recording method described above wherein the R in the formula (I) is an alkyl group having 4 to 10 carbons.
The present invention also provides the image recording method described above wherein, in the substance expressed by the formula (I), R is a butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, or decyl group.
The present invention also provides the image recording method described above wherein the substance expressed in formula (I) above has as its main component at least one substance expressed in formula (I) wherein R is a butyl group selected from among the n-butyl, isobutyl, and t-butyl groups, or has as its main component at least one substance expressed in formula (I) wherein R is a pentyl group selected from among the n-pentyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is a hexyl group selected from among the n-hexyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is a heptyl group selected from among the n-heptyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is an octyl group selected from among the n-octyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is a nonyl group selected from among the n-nonyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is a decyl group selected from among the n-decyl group and other isomers.
The present invention also provides the image recording method described above, wherein the substance expressed in formula (I) above is one wherein n is 0 to 10, and m is 1 to 5.
The present invention also provides the image recording method described above, wherein the substance expressed in formula (I) above has an average molecular weight of 2,000 or less.
The present invention also provides the image recording method described above, wherein the substance expressed in formula (I) above is contained in an amount at 0.5 to 30 wt. %.
The present invention also provides a recording recorded by the image recording method described above.
Detailed descriptions are now given of the coating liquid, image recording method, and recordings of the present invention.
(Coating Liquid)
The coating liquid of the present invention comprises at least water, fine polymer particles, and a penetrating agent, particularly one or more penetrating agents selected from a group made up of acetylene glycol surfactants, acetylene alcohol surfactants, glycol ethers, and 1,2-alkylene glycols.
By fine polymer particles here is meant resins in general. That is, water soluble resins, and water insoluble resins dispersed in a fine particle form in water (generally expressed as emulsions, dispersions, latexes, or suspensions) in general.
For the fine polymer particles that can be used in the coating liquid of the present invention, it is possible to use anything so long as it will stably dissolve and/or disperse in water. The weight average molecular weight thereof should be within a range of 2,000 to 300,000 with 3,000 to 100,000 being a preferable range. If the weight average molecular weight is too low, image protection will cease to be adequate. If the weight average molecular weight is too high, the viscosity will be too high for coating with an ink jet recording procedure and it will be difficult to use.
Examples of such fine polymer particles include polyacrylic acids, styrene-acrylic acid compolymers, styrene-acrylic acid-acrylic acid alkyl ester copolymers, styrene-maleic acid copolymers, styrene-maleic acid-acrylic acid alkyl ester copolymers, styrene-methacrylic acid copolymers, styrene-methacrylic acid-acrylic acid alkyl ester copolymers, and styrene-maleic acid-half ester copolymers, together with salts thereof.
Also, the fine polymer particles contained in the coating liquid of the present invention may be used as an aqueous emulsion. This aqueous emulsion should be one the continuous phase whereof is water, and the dispersion phase whereof is an acrylic resin, methacrylic resin, styrene resin, urethane resin, acrylamide resin, epoxy resin, or mixture thereof. It is particularly desirable that the dispersion phase consist of acrylic acid and/or methacrylic acid. For the aqueous emulsion used in the coating liquid of the present invention, one consisting of the fine polymer particles noted earlier can be used, but it is particularly desirable that it exhibit film forming properties, with a minimum film formation temperature that is at or below room temperature (but minus 10xc2x0 C. or greater) at the location where the printer is used, and preferably a temperature no less than 0xc2x0 C. and no greater than 20xc2x0 C. When the minimum film formation temperature is within this temperature range, there is no need to separately employ a special heating apparatus when forming the coating layer, thereby making it possible to make the image recording apparatus smaller and lighter in weight, with another benefit being that operation in not onerous during image formation.
By the fine polymer particles xe2x80x9cexhibiting film formation propertiesxe2x80x9d is here meant that the fine polymer particles have the capability of forming a coating film, when maintained at or above the minimum film formation temperature thereof, by the fine particles uniting and fusing together. Accordingly, when fine polymer particles having film forming properties are used, the fine polymer particles fuse and join together on the recording medium so that a coating film is formed. As a result, the rubbing resistance, water resistance, and glossiness of the recording can be greatly improved.
The fine polymer particles described in the foregoing is particularly well suited for use as an aqueous emulsion configured solely of a resin or resins having an acid value of 100 or less. When the acid value of the resin in the aqueous emulsion is 100 or lower, the resin will be substantially insoluble in water and, as a consequence, a coating layer formed solely therefrom will also be insoluble in water. Accordingly, in images whereon a coating layer is formed, even when a dye is used as the colorant, a benefit is gained in that recordings are obtained which exhibit good water resistance. Specific examples of such aqueous emulsions that can be cited include the Joncryl emulsions J-390, J-711, J-511, J-7001, J-632, J-741, J-450, J-840, J-47J, J-734, J-7600, J-775, J-537, J-352, J-790, J-780, and J-1535 (these being the names of products made by Johnson Polymer Co., Ltd.), Primal E-2212, Primal I-62, Primal I-94, Primal I-98, and Primal I-100 (products produced by Rohm and Haas Co.), etc., all of which are commercially available and usable as they are.
The amount of such fine polymer particles contained in the coating liquids of the present invention need only be such as both to enable images on recording mediums to be thoroughly coated when sprayed with an ink jet recording procedure and to cause no problems such as nozzle clogging when performing ink jet recording, with 1 to 40 wt. % in the coating liquid being a suitable amount, but preferably 2 to 20 wt. %, and more preferably 4 to 15 wt. %. When the fine polymer particles are used as an aqueous emulsion, the cited addition amounts correspond to the amounts of the solid resin part.
The surface tension of the coating liquids in the present invention should be 40 mN/m or less at 20xc2x0 C. By making the surface tension 40 mN/m or lower, it is possible to form more uniform coating layers.
The coating liquids of the present invention should contain penetrating agents consisting of acetylene glycol or acetylene alcohol surfactants. By adding such penetrating agents as these, penetration into the recording medium is enhanced, and coating liquid fixation is also enhanced, which are benefits.
Citable examples of acetylene glycol surfactants include those wherein an average 30 or fewer ethylene oxy groups and/or propylene oxy groups are added to 2,4,7,9-tetramethyl-5-decine-4,7-diol, 3,6-dimetyl-4-octine-3,6-diol, or 2,4,7,9-tetramethyl-5-decine-4,7-diol, 3,6-dimethyl-4-octine-3,6-diol, and citable examples of acetylene alcohol surfactants include those wherein on average 30 or fewer ethylene oxy groups and/or propylene oxy groups are added to 2,4-dimethyl-5-hexine-3-ol, 3,5-dimethyl-1-hexane-3-ol, or, alternatively, 2,4-dimethyl-5-hexine 3 ol, 3,5-dimethyl-1-hexane-3-ol.
Particularly preferable among these are 2,4,7,9-tetramethyl-5-dicine-4,7,-diol, 3,6-dimethyl-4-octine-3,6-diol, and 3,5-dimethyl-1-hexane-3-ol.
It is also possible to use commercially available products for the acetylene glycol surfactant, specific examples whereof include Surfynol 82, 104, 240, 465, 485, and TG (all available from Air Products Co.), and a specific example of an acetylene alcohol surfactant is Surfynol 61 (also available from Air Products Co.).
The amount of the acetylene glycol surfactant and/or acetylene alcohol surfactant added to the coating liquid of the present invention should be 0.1 to 5.0 wt. % relative to the total volume of coating liquid, with a range of 0.5 to 2 wt. % being more favorable. When the amount added is within this range, the penetration-induced fixation of the coating liquid improves even further, and continuous high-speed coating is made easier.
The coating liquid of the present invention should also contain a penetrating agent selected from among glycol ethers and 1,2-alkylene glycols. By adding these penetrating agents, penetration into the recording medium is enhanced, and coating liquid fixation is also enhanced, which are benefits. These penetrating agents also act to enhance the film forming properties of the fine polymer particles described earlier, whereupon coating layers can be formed effectively on image surfaces.
The glycol ethers noted above should be one or a mixture of two or more substances selected from among a group comprising ethylene glycol mono(alkyl having 4 to 8 carbons) ether, triethylene glycol mono(alkyl having 4 to 8 carbons) ether, propylene glycol mono(alkyl having 3 to 6 carbons), and dipropylene glycol mono(alkyl having 3 to 6 carbons) ether.
Specific examples of glycol ethers, inclusive of glycol ethers other than those noted above, include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, diethylene glycol monoethyl ether, triethylene glycol monoethyl ether, diethylene glycol mono-n-propyl ether, ethylene glycol mono-iso-propyl ether, diethylene glycol mono-iso-propyl ether, triethylene glycol mono-iso-propyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol mono-n-butyl ether, triethylene glycol mono-n-butyl ether, ethylene glycol mono-t-butyl ether, diethylene glycol mono-t-butyl ether, 1-methyl-1-methoxybutanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-t-butyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-iso-propyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-iso-propyl ether, propylene glycol mono-n-butyl ether, and dipropylene glycol mono-n-butyl ether.
For the 1,2-alkylene glycols noted earlier, moreover, 1,2-(alkyl having 4 to 10 carbons) diols are preferable, specific examples whereof include, as specific examples of 1,2-alkylene glycols, 1,2-pentanediol, and 1,2-hexanediol, etc.
The coating liquid of the present invention should also contain 0.5 to 30 wt. % of the glycol ethers and/or 1,2-alkylene glycols noted earlier, and preferably contain 3 to 30 wt. % thereof. When that amount is less than 0.5 wt. %, the effect of enhancing penetration into the recording medium diminishes and the coating liquid becomes difficult to fix. When that amount exceeds 30 wt. %, the viscosity of the coating liquid rises and it becomes difficult to use the coating liquid in coating with an ink jet recording procedure. An even more favorable range is 5 to 10 wt. %.
According to a preferable aspect of the coating liquid of the present invention, in view of the fact that some of the acetylene glycol surfactants and/or glycol ethers noted in the foregoing exhibit low solubility in water, it is preferable that that solubility be improved by adding components such as the following. Examples of components that can be added include highly water-soluble glycol ethers, thiodiglycol, 1,4-butane diol, 1,2-pentanediol, 1,5-pentanediol, 1,2-hexane diol, 1,6-hexane diol, propylene glycol, dipropylene glycol, tripropylene glycol or other diols or glycols, as well as surfactants and the like.
The coating liquid of the present invention should contain therein at least one substance expressed in formula (I) below.
R-EOn-POm-Xxe2x80x83xe2x80x83(I)
(where R is an alkyl group having 1 to 12 carbons, the structure whereof is a straight chain or branched structure, x is xe2x80x94H or SO3M (where M is a counter ion that is a hydrogen ion, alkaline metal ion, ammonium ion, or organic ammonium ion), EO is an ethylene oxy group, PO is a propylene oxy group, and n and m are repeating units, representing mean values in the system overall. EO and PO indicate presence in the molecule, with the order thereof being irrelevant.)
In the present invention, moreover, those substances in the xe2x80x9csubstances expressed in formula (I)xe2x80x9d wherein R is the same (regardless of whether n, m, and X are the same or different) are treated as one type.
By adding substances having the structure expressed in formula (I), the ability of the coating liquid to penetrate into the recording medium is enhanced. As a consequence, coating layer fixation is also enhanced, making it easier to perform continuous coating at high speed.
It is preferable that the R expressed in formula (I) be an alkyl group having 4 to 10 carbons. If the number of carbons in R is 3 or fewer, the effect of enhancing penetration will decline.
More specifically, in the substances expressed in formula (I), R should be a group having the number of carbons C4 (butyl group), C5 (pentyl group), C6 (hexyl group), C7 (heptyl group), C8 (octyl group), C9 (nonyl group), or C10 (decyl group). When R is C3 (propyl group) or lower, the effect of enhancing penetrability declines.
According to a more preferable aspect, the number of carbons is 4 to 8, and even more preferably still, 4 to 6. The structure of R may be straight chain or a branched structure. However, when comparing substances having the same number of carbons, those having a branched structure will exhibit higher effectiveness in enhancing penetrability, and so are preferred.
In the coating liquid of the present invention, furthermore, the substance expressed in formula (I) above has as its main component at least one substance expressed in formula (I) wherein R is a butyl group selected from among the n-butyl, isobutyl, and t-butyl groups, or has as its main component at least one substance expressed in formula (I) wherein R is a pentyl group selected from among the n-pentyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is a hexyl group selected from among the n-hexyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is a heptyl group selected from among the n-heptyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is an octyl group selected from among the n-octyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is a nonyl group selected from among the n-nonyl group and other isomers, or has as its main component at least one substance expressed in formula (I) wherein R is a decyl group selected from among the n-decyl group and other isomers.
In the substances expressed in formula (I), when X is xe2x80x94SO3M (where M is a counter ion that is a hydrogen ion, alkaline metal ion, ammonium ion, or organic ammonium ion), the alkaline metal may be Li, Na, or K, and the organic ammonium may be alkyl ammonium, alkanol ammonium, for example, such, for example, as monomethyl ammonium, diethyl ammonium, tripropyl ammonium, monoethanol ammonium, diethanol ammonium, triethanol ammonium, monoisopropanol ammonium, tripropanol ammonium, N-isobutyl alcohol ammonium, N,N-dimethyl ethanol ammonium, N,N-diethyl ethanol ammonium, etc.
When X is hydrogen, if the molecular weight of R or PO is large compared to EO, the hydrophobic property of the substances expressed in formula (I) overall will increase, wherefore the solubility thereof in water will tend to decline. When X is xe2x80x94SO3M, on the other hand, solubility in water is readily obtainable.
In tho coating liquid of the present invention, moreover, in the substances expressed in formula (I), n should be within a range of 0 to 10, and m within a range of 1 to 5.
The average molecular weight of the substance expressed in formula (I) should be 2,000 or less. When the average molecular weight exceeds 2,000, effectiveness in enhancing penetrability declines. It is preferable that the upper limit in this range be 1,000, and even more preferable that it be 500.
The amount of the substances expressed in formula (I) added to the coating liquid is discretionary, but a range of 0.5 to 30 wt. % relative to the total quantity of coating liquid is preferable, with 2 to 15 wt. % being more preferable, and 5 to 13 wt. % more preferable still. When the added amount is less than 0.5 wt. %, the effect of enhancing penetration is weakened, so the effect of enhancing coating liquid fixation declines. When the added amount exceeds 30 wt. %, the viscosity of the coating liquid rises, making coating with an ink jet recording procedure difficult.
In the coating liquid of the present invention, in terms of the components thereof, furthermore, such additives as UV absorbing agents, preservatives, antioxidants, electrical conductivity adjusting agents, pH adjusting agents, viscosity adjusting agents, surface tension adjusting agents, and oxygen absorbents can be appropriately used.
(Image Recording Method and Recordings)
The image recording method according to the present invention is a method wherewith the coating liquid of the present invention, described in the foregoing, is coated on with an ink jet recording procedure. That ink jet recording procedure may be performed by any commonly known method. For this reason, an apparatus for supplying the film coated becomes unnecessary, and there is no particular necessity either of an apparatus for effecting fixation, due to the properties of the coating liquids of the present invention. In order to further enhance fixation and/or image recording speed, however, an apparatus or the like for accelerating fixation or drying by heating or the like after coating may be used.
Another feature of the recording method of the present intention is that the images coated are effected using an ink jet recording procedure. Thereby, the ink jet recording apparatus for forming the images and the ink jet recording apparatus for spraying the coating liquid can be integrated into the same apparatus, and the equipment overall can be reduced in size, but it is also permissible to use two ink jet recording apparatuses, one for image recording and one for coating, connected in series.
With the image recording method of the present invention, moreover, a dye can be used for the colorant in the ink jet recording ink composition for recording images on recording mediums. For the dye used here, the water-soluble dyes used conventionally in ink jet recording ink compositions can be used. Examples of water-soluble dyes that can be used include disperse dye in addition to acid dye, basic dye, and direct dye.
With the recording method of the present invention, moreover, a pigment can be used for the colorant in the ink jet recording ink composition for recording on recording mediums. For the pigment used here, the pigments used conventionally in ink jet recording ink compositions can be used. Inorganic pigments such as titanium oxide, iron oxide, or carbon black, for example, can be used. Such organic pigments as azo pigments (for example, azo lake, insoluble azo pigment, or condensed azo pigment, etc.), polycyclic pigments (for example, phthalocyanine pigment, quinacridone pigment, or thioindigo pigment, etc.), nitro pigment, nitrose pigment, or aniline black can also be used.
Specific examples of inorganic pigments for use in black ink compositions that can be cited include such carbon blacks as furnace black, lampblack, acetylene black, and channel black (C. I. pigment black 7), and also iron oxide pigments and the like.
For organic pigments used in black ink compositions, such black organic pigments as aniline black (C. I. pigment black 1) or the like can be used.
Citable examples of pigments for use in yellow ink compositions include C. I. pigment yellow 1 (Hansa yellow G), 2, 3 (Hansa yellow 10G), 4, 5 (Hansa yellow 5G), 6, 7, 10, 11, 12, 13, 14, 16, 17, 24 (flavanthrone yellow), 34, 35, 37, 53, 55, 65, 73, 74, 75, 81, 83, 93, 94, 95, 97, 98, 99, 108 (anthrapyrimidine yellow), 109, 110, 113, 117 (copper complex salt pigment), 120, 124, 128, 129, 133, 130 (quinophthalone), 139 (isoindolinone), 147, 151, 153 (nickel complex pigment), 154, 167, 172, and 180, etc.
Citable examples of pigments for use in magenta ink compositions include C. I. pigment red 1 (parared), 2, 3 (toluidine red), 4, 5, (1 TR Red), 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38 (pyrazolone red), 40, 41, 42, 88 (thioindigo), 112 (naphthol AS based), 114 (naphthol AS based), 122 (dimethyl quinacridone), 123, 144, 146, 149, 150, 166, 168 (anthroanthrone orange), 170 (naphthol AS based), 171, 175, 176, 177, 178, 179 (perylene maroon), 185, 187, 209 (dichloroquinacridone), 219, 224 (perylene based), 245 (naphthol AS based), or, alternatively, C. I. pigment violet 19 (quinacridone), 23 (dioxazine violet), 32, 33, 36, 38, 43, and 50, etc.
Citable examples of pigments for use in cyan ink compositions include C. I. pigment blue 15, 15:1, 15:2, 15:3, 16 (non-metallic phthalocyanine), 18 (alkali blue toner), 25, 60 (cerulean blue), 65 (violanthrone), and 66 (indigo), etc.
In addition, citable examples of organic pigments for use in color ink compositions other than magenta, cyan, or yellow ink compositions include: C. I. pigment green 7 (phthalocyanine green), 10 (green gold), 36, and 37; C. I. pigment brown 3, 5, 25, and 26; and C. I. pigment orange 1, 2, 5, 7, 13, 14, 15, 16, 24, 34, 36, 38, 40, 43, and 63, etc.
For the pigments noted above, those which are considered soluble and/or dispersable in water using a dispersant can be used. Dispersants can be generally categorized as anionic surfactant, nonionic surfactant, cationic surfactant, amphoteric surfactant, and high-molecular surfactant. Any of these may be selected as a dispersant for use in the ink compositions used in the image recording method of the present invention.
For the pigments noted in the foregoing, furthermore, it is preferable that they be xe2x80x9csurface-treated pigments,xe2x80x9d that is, pigments which have been subjected to a physical or chemical surface treatment so that, by a functional group or salt thereof being grafted to the surface of the pigment particle, either directly or with an intervening polyvalent group, they are rendered dispersable and/or soluble in water without a dispersant.
The functional groups grafted to one pigment particle may be either one or a plurality of types. The type of functional group grafted, and the degree thereof, should be determined as appropriate, giving consideration to the dispersion stability in the ink, color density, and drying characteristics at the front surface of the ink jet head, etc.
Citable examples of functional groups include xe2x80x94OM, xe2x80x94COOM, xe2x80x94COxe2x80x94, SO3M, xe2x80x94SO2NH2, xe2x80x94RSO3M, xe2x80x94PO3HM, xe2x80x94PO3M2, xe2x80x94SO2NHCOR, xe2x80x94NH3, and xe2x80x94NR3 (where M is a hydrogen atom, alkaline metal, ammonium or organic ammonium, R is an alkyl group, a phenyl group that may have a substituent, or a naphthyl group that may have a substituent, having 1 to 12 carbons), etc.
Citable examples of polyvalent groups include alkylene groups, phenylene groups that may have a substituent, and naphthylene groups that may have a substituent, having 1 to 12 carbons.
It is preferable that the pigments noted in the foregoing be surface-treated with a treatment agent containing sulfur so that SO3M and/or xe2x80x94RSO2M (where M is a counter ion that is a hydrogen ion, alkaline metal ion, ammonium ion, or organic ammonium ion) chemically bonds to the surface of the particles thereof. It is preferable, in other words, that those pigments be made capable of dispersing and/or dissolving in water by first dispersing the pigment in a solvent that has no active protons, that is not reactive with sulfonic acid, and wherein the pigment is insoluble or very slightly soluble, and then surface-treating the pigment with either amide-sulfuric acid or a complex of sulfur trioxide and a tertiary amine so that xe2x80x94SO3M and/or xe2x80x94RSO2M chemically bonds to the surface of the particles thereof.
Various commonly known surface treatment means can be employed as the surface treatment means for grafting the functional groups or salts thereof noted in the foregoing to the surface of the pigment, either directly or with an intervening polyvalent group.
Citable examples thereof include means wherewith commercially available oxide carbon black is treated with a solution of sodium hypochlorite or ozone and the carbon black is subjected to a further oxidization treatment to make the surface thereof more hydrophilic (described in Japanese Patent Application Laid-Open No. H7-250578/1995 (published), Japanese Patent Application Laid-Open No. H8-3498/1996 (published), Japanese Patent Application Laid-Open No. H10-120958/1998 (published), Japanese Patent Application Laid Open No. H10-195331/1998 (published), and Japanese Patent Application Laid-Open No. H10-237349/1998 (published), for example), means wherewith carbon black is treated with 3-amine-N-alkyl substituted pyridium bromide (described in Japanese Patent Application Laid-Open No. H10-195360/1998 (published) and Japanese Patent Application Laid-Open No. H10-330665/1998 (published), for example), means wherewith the organic pigment is dispersed in a solvent wherein that organic pigment is insoluble or slightly soluble and sulfone groups are inducted to the pigment particle surface using a sulfonating agent (described in Japanese Patent Application Laid-Open No. H8-283596/1996 (published), Japanese Patent Application Laid-Open No. H10 110110/1998 (published), and Japanese Patent Application Laid-Open No. H10-110111/1988 (published), for example), and means wherewith the organic pigment is dispersed in an alkaline solvent that forms a complex with sulfur trioxide, the surface of the organic pigment is treated by adding sulfur trioxide thereto, and sulfone groups or sulfonamine groups are inducted thereto (described in Japanese Patent Application Laid-Open No. H10-110114/1998 (published), for example). However, the fabrication means for the surface-treated pigments used in the present invention are not limited to or by these means.
The absolute value of the zeta potential of the surface-treated pigment dispersion liquid (aqueous dispersion liquid) used in the ink compositions of the present invention at 20xc2x0 C. and pH 8 to 9 should be 30 mV or higher. That is, because these surface-treated pigments secure dispersion stability by electrical repulsion induced by dispersed groups inducted to the surface of the particles thereof, it is preferable that the potential (zeta potential) at the pigment surface be at or above a certain value. In cases where the penetrating agents described subsequently and the surface-treated pigments described in the foregoing and deemed desirable in the ink compositions of the present invention are added to the ink composition, the absolute value of the zeta potential of the surface-treated pigment dispersion liquid at 20xc2x0 C. and pH 8 to 9 should be 30 mV or higher in order to secure pigment dispersion stability.
The zeta potential of the surface-treated pigment dispersion liquid at 20xc2x0 C. and pH 8 to 9 is measured with a laser Doppler electrophoresis apparatus (ELS-800 produced by Otsuka Electronic).
Surface-treated pigment dispersion liquids exhibiting zeta potential absolute values of 30 mV or higher at 20xc2x0 C. and pH 8 to 9 are obtained by such means as are described subsequently in example, for example.
The amount of pigment added as colorant, although discretionary, should be 0.5 to 20 wt. % relative to the total quantity of ink composition, with a range of 2 to 10 wt. % being preferable. At 0.5 wt. % and above, images having the desired image density are readily obtained, and, at 20 wt. % and below, the ink viscosity can be easily adjusted to facilitate stable discharge in ink jet procedures.
In the ink compositions used in the image recording method of the present invention, it is preferable that one or more substances selected from a group comprising acetylene glycol surfactants, acetylene alcohol surfactants, glycol ethers, and 1,2-alkylene glycols be used as the penetrating agent described earlier.
It is preferable that the acetylene glycol surfactants and acetylene alcohol surfactants used be the same as or similar to those used preferably in the coating liquid described earlier. The amount of each acetylene glycol surfactant and/or acetylene alcohol surfactant added should be 0.1 to 3 wt. % relative to the total quantity of ink composition, with a range of 0.5 to 2 wt. % being preferable. When that amount is less than 0.1 wt. %, it is difficult to obtain an adequate penetration effect, and when 3 wt. % is exceeded, the nozzle surfaces on the ink jet head are wetted, and in some cases it is difficult to obtain stable discharge.
It is preferable that the glycol ethers and 1,2-alkylene glycols used be the same as or similar to those used preferably in the coating liquid described earlier. The amount of such glycol ethers and/or 1,2 alkylene glycols added should constitute a content of 0.5 to 30 wt. % relative to the entire quantity of ink composition, with a content ranging from 3 to 30 wt. % being preferable. When that amount is less than 0.5 wt. %, an adequate penetration effect is difficult to obtain. When 30 wt. % is exceeded, the viscosity of the ink composition rises, and in some cases it is difficult to obtain stable discharge.
The ink composition used in the image recording method of the present invention should also contain at least one substance having the structure expressed in formula (I) below in the ink composition.
R-EOn-POm-Xxe2x80x83xe2x80x83(I)
(where R represents an alkyl group having 1 to 12 carbons, the structure whereof may be either a straight chain or branching; X represents xe2x80x94H or xe2x80x94SO2M (where M is a counter ion that is a hydrogen ion, alkaline metal ion, ammonium ion, or organic ammonium ion); EO represents an ethylene oxy group; PO represents a propylene oxy group; and n and m are repeating units, indicating average values in the system overall. EO and PO indicate presence in the molecule, with the order thereof being irrelevant.)
By adding substances having the structure expressed by the formula (I) above, the ink composition penetrability into the recording medium is enhanced. As to specific examples of substances such as these, substances the same as or similar to those used preferably in the coating liquid described earlier should be used.
The amount of the substances exhibited by formula (I) above added into the ink composition is discretionary, but should be 0.5 to 30 wt. % relative to the entire quantity of ink composition. When the added amount is less than 0.5 wt. %, the affect of enhancing penetrability is weakened, whereas when the added amount exceeds 30 wt. %, the viscosity of the ink composition rises and in some cases it is difficult to obtain stable discharge.
The surface tension of the ink composition used in the image recording method of the present invention should be 40 mN/m or less at 20xc2x0 C.
As components in the ink composition used in the image recording method of the present invention, furthermore, such additives as UV absorbing agents, preservatives, antioxidants, electrical conductivity adjusting agents, pH adjusting agents, viscosity adjusting agents, surface tension adjusting agents, and oxygen absorbents can be appropriately used.
In the image recording method of the present invention, moreover, the film thickness of the dried coating layer need only be such that the recorded images can be thoroughly coated, with 0.1 to 100 xcexcm being reasonable, and a range of 0.5 to 20 xcexcm being preferable. When the colorant in the image recording ink composition is a dye, a range of 2 to 20 xcexcm is to be preferred. When the colorant in the image recording ink composition is one made dispersable and/or soluble in water by a dispersant, a film thickness range of 0.5 to 5 xcexcm is to be preferred. And when the colorant in the image recording ink composition is a surface-treated pigment, a film thickness range of 0.5 to 10 xcexcm is to be preferred.
Paper is generally used for the recording medium used in the image recording method of the present invention, but a resin such as plastic or a metal or the like may also be used if the surface thereof has been treated and it has an ink absorption layer.
Recordings recorded using the image recording method of the present invention exhibit good recording fastness properties such as light resistance, water resistance, and fixation, and good image quality having outstanding glossiness is obtained, making them effective for use in outdoor posters and signs.
When a surface-treated pigment is used as the colorant in the image recording ink composition, in particular, in addition to the qualities noted above, the composition is fast-drying, making it possible to perform recording with high image density and high picture quality, and rubbing resistance can also be improved. Thus such image recording ink compositions are particularly effective for use in outdoor posters and signs.

Coating liquid, and image recording method and recording using same


A method for manufacturing a polishing pad prevents slurry leaks and provides a pad that can be used to provide high optical detection accuracy. The method for manufacturing a polishing pad includes forming a groove for injecting a light-transmitting region forming material on the back surface of a polishing layer; injecting the light-transmitting region forming material into the groove and curing the material to form a light-transmitting region; and buffing the front surface of the polishing layer to expose the light-transmitting region on the front surface.

Production of a semiconductor device involves a step of forming an electroconductive film on the surface of a wafer to form a wiring layer by photolithography, etching etc., a step of forming an interlaminar insulating film on the wiring layer, etc., and an uneven surface made of an electroconductive material such as metal and an insulating material is generated on the surface of a wafer by these steps. In recent years, processing for fine wiring and multilayer wiring is advancing for the purpose of higher integration of semiconductor integrated circuits, and accordingly techniques of planarizing an uneven surface of a wafer have become important.
As the method of planarizing an uneven surface of a wafer, a CMP method is generally used. CMP is a technique wherein while the surface of a wafer to be polished is pressed against a polishing surface of a polishing pad, the surface of the wafer is polished with an abrasive in the form of slurry having abrasive grains dispersed therein (hereinafter, referred to as slurry). As shown in FIG. 1, a polishing apparatus used generally in CMP is provided for example with a polishing platen 2 for supporting a polishing pad 1, a supporting stand (polishing head) 5 for supporting a polished material (wafer) 4, a backing material for uniformly pressurizing a wafer, and a mechanism of feeding an abrasive. The polishing pad 1 is fitted with the polishing platen 2 for example via a double-sided tape. The polishing platen 2 and the supporting stand 5 are provided with rotating shafts 6 and 7 respectively and are arranged such that the polishing pad 1 and the polished material 4, both of which are supported by them, are opposed to each other. The supporting stand 5 is provided with a pressurizing mechanism for pushing the polished material 4 against the polishing pad 1.
When CMP is conducted, there is a problem of judging the planarity of wafer surface. That is, the point in time when desired surface properties or planar state are reached should be detected. With respect to the thickness of an oxide film, polishing speed etc., the polishing treatment of a test wafer has been conducted by periodically treating the wafer, and after the results are confirmed, a wafer serving as a product is subjected to polishing treatment.
In this method, however, the treatment time of a test wafer and the cost for the treatment are wasteful, and a test wafer and a product wafer not subjected to processing are different in polishing results due to a loading effect unique to CMP, and accurate prediction of processing results is difficult without actual processing of the product wafer.
Accordingly, there is need in recent years for a method capable of in situ detection of the point in time when desired surface properties and thickness are attained at the time of CMP processing, in order to solve the problem described above. While various methods are used for such detection, an optical detection method using a film thickness monitoring mechanism with a laser beam, which is incorporated in a rotary platen, is becoming the mainstream in view of measurement accuracy or spatial resolution in non-contact measurement.
The optical detection means is specifically a method of detecting the endpoint of polishing by irradiating a wafer via a polishing pad through a window (light-transmitting region) with a light beam, and monitoring an interference signal generated by reflection of the light beam.
In such method, the endpoint is determined by knowing an approximate depth of surface unevenness by monitoring a change in the thickness of a surface layer of a wafer. When such change in thickness becomes equal to the thickness of unevenness, the CMP process is finished. As a method of detecting the endpoint of polishing by such optical means and a polishing pad used in the method, various methods and polishing pads have been proposed.
A polishing pad having, as least a part thereof, a solid and uniform transparent polymer sheet passing a light of wavelengths of 190 to 3500 nm therethrough is disclosed (Patent Literature 1). Further, a polishing pad having a stepped transparent plug inserted into it is disclosed (Patent Literature 2). A polishing pad having a transparent plug on the same surface as a polishing surface is disclosed (Patent Literature 3). There is also disclosed a polishing pad having a window produced from an aliphatic polyisocyanate, a hydroxyl-containing material and a curing agent (Patent Literature 4).
Besides, a proposal is also offered for preventing a slurry from leaking out an interface (joint line) between a polishing region and a light-transmitting region (Patent Literature 5 and 6).
There is also disclosed a method for manufacturing a polishing pad, which includes placing a rod or plug of a first resin in a liquid of a second resin, curing the second resin to prepare a formed product, and slicing the formed product to form a polishing pad having a light-transmitting region and a polishing region integrated together (Patent Literature 7). However, since this manufacturing method includes inserting a transparent plug into an opaque resin remaining in a liquid state and curing the opaque resin, too high pressure or stress may be applied to the transparent plug from the opaque resin in the process of curing the opaque resin, which may cause residual stress deformation or swelling of the transparent plug. The residual stress deformation or swelling degrades the flatness of the transparent plug to make the optical detection accuracy unsatisfactory. In addition, the stress caused by the thermal contraction difference between both materials remains at the bonding interface between both materials during the forming process, so that separation may easily occur at the bonding interface, which may cause slurry leaks.
There is also disclosed an integrally-formed polishing pad having a transparent polymer material region and an opaque polymer material region placed adjacent thereto (Patent Literature 8). In the production of this polishing pad, a fluid polymer material is cured at different cure rates in the respective regions of a molding cavity so that a transparent region and an opaque region can be integrally formed. In this production method, however, the temperature control to change the cure rate is difficult so that the light transmittance of the transparent region may vary or it may be impossible to obtain satisfactory light transmittance.
Patent Literature 1: JP-A National Publication (Laid-Open) No. 11-512977
Patent Literature 2: JP-A 9-7985
Patent Literature 3: JP-A 10-83977
Patent Literature 4: JP-A 2005-175464
Patent Literature 5: JP-A 2001-291686
Patent Literature 6: JP-A National Publication (Laid-Open) No. 2003-510826
Patent Literature 7: JP-A 2005-210143
Patent Literature 8: JP-A National Publication (Laid-Open) No. 2003-507199


Power savings is provided to users of various electronic devices by monitoring the times and locations at which those users activate, deactivate, or otherwise change an operational state of one or more functional elements of a device. Other contextual or environmental information can be captured as well when the user performs such an action. One or more statistical analysis or prediction algorithms can be used to determine when and/or where the user is likely to repeat the one or more actions, where a confidence level of the prediction can be impacted at least in part by the environmental and contextual factors. When a prediction has a minimum level of confidence, a corresponding action can be performed automatically by the device when the relevant factors are met. Changes in behavior can be monitored such that the predictions can be refined over time.

People are utilizing portable electronic devices for an increasing number and variety of tasks. It is not uncommon for a user to have a personal media player, notebook computer, cell phone, and electronic book reader, among other such devices. Further, the demands on these devices increase as the devices offer enhanced functionality. For example, a tablet computer or portable gaming platform might perform most, if not all, of the tasks performed by the devices above. Thus, the amount of resource and power consumption required by these devices tends to increase, along with the need for the devices to have sufficient power for a user to utilize the devices as necessary.
In many instances a user will utilize certain functionality during certain times of day, such as using Bluetooth® while driving or WiFi while at home. If the user wants to conserve power on the device, the user might turn this functionality off when it is not needed. In many cases, however, the user will forget to turn the functionality off, which can lead to an unnecessary drain on power, as well as on aspects such as processing capacity and bandwidth. Further, even when the user remembers to turn the functionality off, the user might not enjoy having to continually turn certain functionality on and off each day.

Statistical approach to power management for electronic devices


The present disclosure provides systems and methods for enhanced wireless communication security. The preambles used for the identification of an upcoming wireless communication may be periodically changed (e.g., dynamic), on a time basis, based on a secret key function shared between the communicating parties. In this way, only the intended parties are able to recognize the start of an ongoing communication, synchronize with the transmitters, and access the information contained therein. An attacker, being unaware of the specific preamble sequence used for the synchronization, will not recognize the pattern of the communication, and thus will be unable to recognize when communications are ongoing. Additional authentication measures may also be implemented with the transmissions.

Wireless communications are today widespread and offer crucial advantages over wired solutions. Due to the absence of any physical connections, wireless communications overcome limitations that result from unsuitable locations and physical obstacles to enable ubiquitous connectivity. Wireless communications require tight synchronization between communicating entities to enable such connectivity. In typical wireless communication technologies, this is achieved by prefixing transmitted information or messages with dedicated preambles. The preamble sequences are characterized by different contents and lengths, and they are meant to allow a receiver to synchronize with a transmitter and correctly reconstruct the information carried in a message. The choice of the particular preamble sequence is typically fixed for each communication technology and it is optimized based on the particular modulation scheme used at the physical layer, the operating frequency, as well as the length of the messages involved in the communications.
Due to the intrinsic nature of the wireless communication medium, wireless communications are exposed to a wide range of attacks that intend to interfere with the wireless communications. For example, an attacker may carry out an attack that intercepts the communications or prevents the communication from happening. Among these attacks, the most harmful may be considered jamming, eavesdropping, and man-in-the-middle attacks. A reactive jamming attack, for instance, involves an attacker or a device recognizing that communications are occurring, and in response, injecting interference into the communication channel so that the receiver cannot recognize the message.
Each of these harmful attacks is based on an attacker that is able to recognize the presence of ongoing communications, eventually analyze their pattern and, attempt to compromise the security of the communications. For instance, depending on the attacker's specific target, the attacker may jam the communication, impersonate a legitimate party, or eavesdrop on the communication, among other security-compromising activities. An attacker may achieve a successful attack by looking at the communication signal on a particular operating frequency and identifying the specific preamble sequence uniquely characterizing the particular communication technology so that the attacker may recognize when communications are ongoing. Accordingly, at least one vulnerability in typical wireless communications is that the preamble sequence is fixed. While a fixed preamble helps receivers optimally identify messages by receivers, the fixed preamble also enables attackers to identify ongoing communications enabling attackers to compromise the security of those communications.
Indeed, typical reactive jamming devices available on the market leverage the knowledge that communication technologies utilize a specific fixed preamble sequence. In particular, typical reactive jamming devices listen on a particular operating frequency used for the communication and, as soon as the device detects the presence of the target preamble sequence, the device starts jamming by emitting random noise. The random noise disrupts the quality of the communication. Typical solutions to evade reactive jamming are based on "network-oriented" schemes, where the network as a whole is able to escape jamming by taking advantage of a weakness of the attacker. For example, the network may utilize a set of frequencies that the attacker cannot jam at the same time or other physical limitations of the jammer. These typical solutions, however, do not provide security at the individual transmitter/receiver level.
Accordingly, a need exists for a solution to the above-identified problems.

Dynamic preambles for establishing secure communication channels

QATAR FOUNDATION FOR EDUCATION, SCIENCE AND COMMUNITY DEVELOPMENT


A system for aiding the navigation of an aircraft able to be piloted remotely by an operator includes means for transmitting data allowing the operator to dialogue with an air traffic controller according to at least one mode of dialogue and means for monitoring the flight parameters, notably aircraft state parameters and navigation parameters. The system also includes a means for detecting flight events, a means for formulating a message corresponding to a flight event, a means for scheduling the message in a list of messages, and a means for synthesizing the message in a mode of dialogue.

In current conflicts, drones are increasingly being used for recognizing and attacking non-cooperative targets. Moreover, there exist numerous applications for systems of Drones in the civil sphere (fertilizer spreading in agriculture, monitoring of forest fires, Search & Rescue, event surveillance, monitoring of demonstrations). Thus, the targets sought are often located in or in proximity to civilian spaces. Moreover, it is often compulsory for the drones to pass through airspaces subject to civil air traffic control, when their takeoff/landing base is situated inside the borders of the states which dispatch them. The insertion of drones into these regulated traffic spaces is problematic since these craft do not possess the complete insertion capabilities. Furthermore, the avionics systems carrying out the flight management functions are massively located on the ground, the aircraft carrying on board only the strict minimum for short-term navigation. Consequently, these craft are bound by draconian procedures: several days' notice, escort aircraft, closure of civilian traffic during a time slot.
Currently, when the mission is not exclusively conducted in a segregated space, that is to say prohibited to civil operations, and when the communications are required between the operator of the drone and the air traffic control services, two solutions are applied. According to a first solution, the drone is used as communication relay between the operator and the controller. The operator communicates voice messages to the drone by means of analogue or digital transmission (VHF or VoIP, Voice over IP); the drone comprises a means for converting the digital voice messages into analogue voice messages so as to transmit by means of an analogue transmission of VHF ("very high frequency"), HF ("High Frequency") type. The transmission chain in the direction from the controller to the operator is conversely identical. However, this technical solution requires the operator to have all the phraseology for communicating with the controller and consequently this task monopolizes a significant part of his attention in managing the drone. Moreover, the bandwidth necessary for digital transmission between the operator and the drone is greatly utilized for message transmission in voice format. Finally, a significant temporal latency may be introduced if the ground station of the Drone where the operator is situated is several hundred or indeed thousands of kilometers from the aircraft. According to a second solution, the operator telephones the controller directly. However, this solution involves the controller managing each drone individually and specifically. Moreover, the operator must also be responsible for all the phraseology, thus implying the same drawback aforementioned in the first solution. Having regard to the absence of any onboard pilot, it is indispensable to equip drones with more sophisticated functions assisting the ground operator in his remote management of the aircraft.
It is known to use in conventional aircraft (with onboard pilot) devices for communications by digital transmission (CPDLC for "Controller Pilot Data Link Communications") between the pilot and the air traffic controller using standardized text messages using the vocal phraseology customarily used by an air traffic controller. These CPDLC communication systems make it possible to maintain the communication over great distances with respect to radio frequency communications and especially to reduce the operational load for dialogue between the pilot and the air traffic controller. However, CPDLC dialogue mode systems are not deployed in all airspace controls and many still communicate solely by voice messaging.


The present invention provides a capacitive touch sensing device and a scanning method thereof. The present invention divides a scanning procedure of an electrode matrix into two stages. First, it scans broadly for determining whether the potential signal of at least one driving line of the electrode matrix is changed or not. After that, the present invention is only directed to the driving line which the potential signal is changed to scan in detail, to determine whether the potential signal of each coupling node on the driving line is changed or not. Therefore, the present invention can achieve the purpose of improving sensing efficiency of the capacitive touch sensing device.

1. Field of the Invention
The present invention relates to a capacitive touch sensing device and scanning method thereof.
2. Description of Related Art
Recently, the touch sensing devices that use capacitive technology have become more popular in different electronic devices. As a result, users now can input information to different devices using multiple touch input.
Please refer to FIG. 1, wherein a circuit block schematic view of a traditional capacitive touch sensing device is shown. As depicted, the capacitive touch sensing device 9 includes an electrode matrix 90, a first multiplexer 91, a driving circuit 92, a second multiplexer 93, an integrator 94, and an analog-to-digital converter 95. The electrode matrix 90 comprises a plurality of driving lines LD and a plurality of sensing lines LS; each driving line LD crosses each sensing line LS to form a coupling node 901. In addition, each coupling node 901 would induce an equivalent capacitor CE according to rules of electrical specification.
The first multiplexer 91 switches different channels in sequence for transmitting a pulse signal outputted from the driving circuit 92 to each driving line LD in turn. The second multiplexer 93 switches to receive a charge voltage induced by each sensing line LS in sequence. In other words, through the operation of the first multiplexer 91 and the second multiplexer 93, the pulse signal would make the equivalent capacitor CE induced by each coupling node 901 to be charged and discharged in turn. The integrator 94 connects to the second multiplexer 93, and stores the voltage of each equivalent capacitor CE to an integrating capacitor CI through an integrating element A1. The analog-to-digital converter 95 connects to the integrator 94, and performs an analog-to digital conversion.
The capacitive touch sensing device 9 would perform an initial process and a touch sensing process in design. In the initial process, the capacitive touch sensing device 9 would store the potential signal of equivalent capacitor CE induced by each coupling node 901 to be a base potential value individually. After that, in the touch sensing process, the capacitive touch sensing device 9 would compare the present potential signal of equivalent capacitor CE induced by each coupling node 901, with the correspondingly base potential value stored in the initial process. Thus, if any one of the coupling nodes 901 has been touched, the present potential signal of equivalent capacitor CE induced by the touched coupling node 901, would be lower than the corresponding base potential value. Therefore, the traditional capacitive touch sensing device 9 decides the coordinate position of the touched coupling node 901 by determining whether the potential signal of each equivalent capacitor CE is changed or not. However, the traditional technology can only scan and sense one coupling node at a time. If the size of the capacitive touch panel gets larger, or the requirement of the touching accuracy gets higher, the driving lines and the sensing lines would be increased, and the amount of the coupling nodes would also be increased. Accordingly, the capacitive touch sensing device would require more time to scan and sense all coupling nodes, and sensing efficiency would be reduced, and as a result, application requirement could not be met.

Touch sensing device and scanning method thereof


Caricature exaggeration systems, engines, and methods create a drawing of a facial image, compare relationships among facial features in the drawing to corresponding relationships in facial images and corresponding caricatures in a database, and automatically exaggerate at least one relationship among facial features in the drawing based on the facial images and the corresponding caricatures in the database.

An artist's caricature of a face catches one's attention because the artistically exaggerated features impart a comic, grotesque, literary, political, or editorial quality. A worthy caricature emphasizes facial features that make the caricatured person different from everyone else. Hence, the caricatured person is still recognizable yet the exaggerated features make the caricature interesting for viewers.
"Exaggeration" as used herein, means a change in an aspect of a facial image. A usual connotation of the term often implies an increase or an enlargement in something. With regard to the art of caricature, however, an exaggeration can also be a decrease or a diminution of some facial aspect or dimension. In fact, as used herein, exaggeration often means a furthering of some noticeable facial aspect (that distinguishes a person from other people) in the same direction that makes the facial aspect stand out in the first place. So if a person's eyes seem too close together, a good caricature exaggerates this feature by moving the eyes even closer together—but the distance between the eyes decreases: hardly an exaggeration in the conventional sense of the word.
Recently, a number of non-photorealistic rendering algorithms have been proposed to allow computers to draw sketches, engravings, oil paintings, and variously styled line drawings. For example, algorithms for sketches are presented in: H. Chen, Y. Q. Xu, H. Y. Shum, S. C. Zhu, and N. N. Zheng, "Example-based facial sketch generation with non-parametric sampling," ICCV 2001, 2001. Algorithms for engravings are presented in: V. Ostromoukhov, "Digital facial engraving," Proceedings of SIGGRAPH 1999, 1999. Algorithms for oil paintings are presented in: A. Hertzmann, C. E. Jacobs, N. Oliver, B. Curless, and D. H. Salesin, "Image analogies," Proceedings of SIGGRAPH 2001, Computer Graphics Proceedings, Annual Conference Series, 2001. Algorithms for variously styled line-drawings are presented in: W. T. Freeman, J. B. Tenenbaum, and E. Pasztor, "An example-based approach to style translation for line drawings," Technical Report TR99-11, 1999; and H. Koshimizu et al., "On kansei facial processing for computerized facial caricaturing system picasso," IEEE International Conference on Systems, Man, and Cybernetics, vol. 6, 1999, (the "Koshimizu reference"). These conventional systems focus on the painting style or stroke style of the image but not on the exaggeration of faces.
Some tools have been introduced to aid users in creating caricatures (e.g., B. Gooch, E. Reinhard, and A. Gooch, "Perception-driven black-and-white drawings and caricatures," Technical Report UUCS-02-002, 2002; and E. Akleman, J. Palmer, and R. Logan, "Making extreme caricatures with a new interactive 2D deformation technique with simplicial complexes," Proceedings of Visual 2001, 2000) but these tools do not instruct users how to perform exaggeration. While experienced caricaturists may be able to generate interesting caricatures with the above-cited tools, inexperienced users may have difficulty determining how to exaggerate a face.
Some conventional systems try to automatically generate caricatures using a computer. The most common way to attempt exaggeration using a computer employs finding differences in facial features (eye, nose, mouth, chin, etc.) between a face to be caricatured and an average face and then enlarging these facial features. This approach has been employed in the work of S. E. Brennan, "Caricature generator: The dynamic exaggeration of faces by computer," Leonardo, 18(3): 170-178, 1985; in the work of T. Valentine, "A unified account of the effects of distinctiveness, inversion and race in face recognition," The Quarterly Journal of Experimental Psychology, 43(2): 161-204, 1991; and in the Koshimizu reference, cited above. These conventional systems can provide users with some information about how to perform exaggeration and can allow for adjustment of the exaggeration. But as shown in FIG. 1, these conventional systems are limited to exaggerating only individual features of a face, such as the eyes 102, 102′, 102″ or the mouth 104, 104′, 104.″ In response to a user adjusting the degree of exaggeration, these conventional systems have no mechanism for maintaining facial integrity. For example, sometimes if the distance between two eyes has been enlarged too far, the eyes may extend beyond the outside contour of the face.
A set of pre-designed exaggeration templates is used to generate caricatures in the work of H. Chen, N. N. Zheng, L. Liang, Y. Li, Y. Q. Xu, and H. Y. Shum, "Pictoon: A personalized image-based cartoon system," ACM Multimedia 2002, 2002. The templates allow facial integrity to be maintained but users have to choose the template to be used for performing exaggeration and the degree of exaggeration is fixed.
In one reference, a caricature training database is used and some exaggeration prototypes are learned from the database using principle component analysis ("PCA") in the work of L. Liang, H. Chen, Y. Q. Xu, and H. Y. Shum, "Example-based caricature generation with exaggeration," IEEE Pacific Graphics 2002, 2002. When a new facial image is presented to this conventional system, a particular prototype is chosen automatically and the magnitude of the exaggeration is discovered through linear regression. This system informs a user how to perform exaggeration and determines the magnitude of exaggeration automatically, but users cannot adjust the magnitude of exaggeration applied. Additionally, this conventional system has no mechanism to maintain facial integrity and suffers the additional limitation that its training database is partitioned according to learned exaggeration prototypes, so if there are only a few training samples for each prototype then instability is likely.


An apparatus is disclosed for positioning surgical implants adjacent to body tissue. The apparatus includes a delivery device having a support member positioned at the distal end of an elongated rod, and a surgical implant releasably secured to the support member. The invention also provides a method for positioning surgical implants adjacent to body tissue using the apparatus of the present invention.

1. Field of the Invention
The present invention relates to an apparatus and method for positioning surgical implants adjacent to body tissue to facilitate the fastening of the implant to the body tissue.
2. Description of the Related Art
Hernias are abnormal protrusions of an organ or other body structure through a defect or natural opening in a covering membrane, muscle or bone. An inguinal hernia is a protrusion which makes its way through the abdomen in the inguinal (groin) region. Hernias may be divided into three general classes: direct inguinal hernia, indirect inguinal hernia and femoral hernia. In both a direct and indirect inguinal hernias, a part of the intestine may protrude through a defect (opening or tear) in the supporting abdominal wall to form a hernial sac. In a femoral hernia, a portion of the intestine is forced through the femoral ring into the femoral canal forming a hernial sac.
Hernia repair typically requires surgery which generally includes an incision in the groin ranging up to six inches in length. Several layers of the abdominal wall are generally separated to reach the herniated portions. During the procedure, the opening or tear in the abdominal wall is closed in a manner which resembles the tying of a sack at the neck. Often a surgical mesh is attached by sutures directly over the repaired hernia opening to provide a reinforcement to the opening.
Traditionally, such hernia repairs involved major invasive surgical procedures which often caused excessive trauma to the patient and necessitated unusually long post-operative recuperative periods. In addition, numerous complications, related directly or indirectly to the surgery often resulted, including bleeding, infection, testicular atrophy, organ damage, nerve damage, blood vessel damage, etc. Further, cutting through the numerous layers of tissue to obtain access to the herniated area often caused severe trauma to the patient. A detailed discussion of traditional hernia repair may be found in "Hernia Repair Without Disability, Second Edition", by Irving L. Lichtenstein. Such invasive surgical procedures have also been utilized in other areas of the body, including surgery on the gall bladder, appendix, lungs and the like.
To, avoid many of the previously stated risks and problems, the use of laparoscopic and endoscopic surgical procedures ave been relatively popular and have provided additional incentive to develop the procedures further. In laparoscopic procedures, surgery is performed in the interior of the abdomen through a small incision. Similarly, in endoscopic procedures, surgery is performed in any hollow viscus of the body through narrow endoscopic tubes inserted through small entrance wounds in the skin.
Laparoscopic and endoscopic procedures generally require that the surgical region be insufflated. Accordingly, any instrumentation inserted into the body must be sealed to ensure that gases do not enter or exit the body through the incision. Moreover, laparoscopic and endoscopic procedures often require the surgeon to act on organs, tissues and/or vessels far removed from the incision. Thus, instruments used in such procedures are typically long and narrow while being functionally controllable from a proximal end of the instrument.
In hernia surgery, as compared to gall bladder surgery, certain procedures and instruments are the same, and certain instrument requirements differ. For example, in hernia surgery a suitable mesh material is generally sutured over the opening in the tissue. Often, the mesh material is attached by sutures and left within the body to act as a reinforcing agent for tissue regrowth in the area of the surgery. Ore example of a mesh material currently utilized in hernia surgery includes a polypropylene material marketed by C. R. Bard under the trademark MARLEX. Another example of a mesh material is a tri-fluoroethylene material marketed by W. L. Gore & Associates, Newark, Delaware, under the trademark GCRE-TEX.
As noted, during conventional invasive surgical procedures, such mesh materials are manually placed over the defect in the abdominal wall and are often sutured within the surgical opening by conventional suturing techniques. However, with the advent of laparoscopic surgery the need for suitable mesh, mesh positioning and mesh attachment techniques through the relatively narrow endoscopic tubes or cannulas is clearly defined. Up to the present, such devices and techniques for mesh positioning have not yet been developed.
Heretofore, resilient umbrella-type devices or extractors have been provided to remove objects from body tissue. Exemplary of these devices is U.S. Pat. No. 4,557,255 to Goodman. Goodman discloses a purse-like surgical net which is operable for retrieving stones and the like from within the human body.
U.S. Pat. No. 4,190,042 to Sinnreich discloses a resilient surgical retractor which in an unstressed condition forms a hook-like appendage at the distal end of the retractor.
U.S. Pat. No. 4,586,502 to Bedi et al. discloses a surgical instrument for implanting an "H"-shaped fastener in body tissue and a method of applying fasteners to skin or other tissue in a surgical procedure as an alternative to suturing a wound or surgical incision.
However, there remains a need for an apparatus which facilitates the securing of surgical implants for endoscopic positioning of the implant adjacent to body tissue. In addition to the above apparatus, the present invention relates to a method for positioning surgical implants adjacent to body tissue for stapling.


The invention provides compositions containing a mixture of (a) an enzyme that possesses substantial 3′-5′ exonuclease activity (b) a DNA polymerase with less 3′-5′ exonuclease activity than the enzyme with substantial 3′-5′ exonuclease activity. Preferably, the DNA polymerase for inclusion in the compositions are DNA polymerases that substantially lack 3′-5′ exonuclease activity. A preferred embodiment of the invention is a composition comprising Taq DNA polymerase (isolated from Thermus aquaticus) and Pfu DNA polymerase (isolated from Pvrococcus furiosus). Another aspect of the invention is to provide methods for synthesizing polynucleotides using compositions comprising an enzyme that possesses substantial 3′-5′ exonuclease activity and a DNA polymerase with less 3′-5′ exonuclease activity than the enzymes possessing substantial 3′-5′ exonuclease activity, preferably a DNA polymerase that substantially lacks 3′-5′ exonuclease activity. Another aspect involves the use the subject method of polynucleotide synthesis to carry out the synthesis step in a polymerase chain reaction experiment.

DNA polymerases catalyze the synthesis of DNA and can be found in all cells as well as being encoded in numerous viruses. Although all DNA polymerases possess 5′-3′ DNA polymerase activity, DNA polymerases differ from one another in numerous other properties. For example, some enzymatic activities that are possessed by some DNA polymerases, but absent in other DNA polymerases include: double stranded DNA 5′-3′ exonuclease activity, single-stranded DNA 3′-5′ exonuclease activity, double-stranded 3′-5′ DNA exonuclease activity, RNase H activity, reverse transcriptase activity, and the like. Additionally, different DNA polymerases may have different optimal pH and temperature ranges for activity. Furthermore, DNA polymerases may differ in the rate in which they catalyze DNA synthesis.
Purified DNA polymerases have numerous uses in vitro. A detailed description of DNA polymerases, including methods for their isolation, can be found among other places, in DNA Replication 2nd edition, by Komberg and Baker, W. H. Freeman & Company, New York, N.Y. 1991. In vitro uses of DNA polymerases include, for example, the labeling and synthesis of hybridization probes, DNA sequencing, and DNA amplification. A DNA amplification method employing DNA polymerases that has been particularly useful is the polymerase chain reaction (PCR) technique. The technique of PCR is described in numerous publications, including, PCR: A Practical Approach, M. J. McPherson, et al., IRL Press (1991), PCR Protocols: A Guide to Methods and Applications, by Innis, et al., Academic Press (1990), and PCR Technology: Principals and Applications for DNA Amplification, H. A. Erlich, Stockton Press (1989). PCR is also described in many U.S. patents, including U.S. Pat. Nos. 4,683,195; 4,683,202; 4,800,159; 4,965,188; 4,889,818; 5,075,216; 5,079,352; 5,104,792; 5,023,171; 5,091,310; and 5,066,584, which are hereby incorporated by reference. The PCR technique typically involves the step of denaturing a polynucleotide, followed by the step of annealing at least a pair of primer oligonucleotides to the denatured polynucleotide, i.e., hybridizing the primer to the denatured polynucleotide template. After the annealing step, an enzyme with polymerase activity catalyzes synthesis of a new polynucleotide strand that incorporates the primer oligonucleotide and uses the original denatured polynucleotide as a synthesis template.
In many instances, a given DNA polymerase may fail to synthesize the desired polynucleotide product. These failures may be attributable to a number of reasons including such problems as template and primer base pair mismatches, lack of proofreading, insufficient rate of synthesis, high misincorporation rate, inability to transcribe GC or AT rich regions, lack of sufficient processivity (processivity refers to the length of synthesis product formed before the polymerase stops synthesis), etc. It is therefore of interest to provide new methods and compositions for improved polynucleotide synthesis over a wide variety of experimental conditions.

This patent is subject to a terminal disclaimer.

Polymerase compositions and uses thereof