Abstract: Disclosed herein are glucosyltransferases with modified amino acid sequences. Such engineered enzymes exhibit improved alpha-glucan product yields and/or lower leucrose yields, for example. Further disclosed are reactions and methods in which engineered glucosyltransferases are used to produce alpha-glucan.

Abstract: In one aspect, methods of printing a color 3D article are described herein. In some embodiments, a method described herein comprises receiving data representing a surface colorization of the article, and transforming the data representing the surface colorization of the article into voxel data of the article. The voxel data comprises (a) location values and at least one of (b) color values and (c) transparency values for a plurality of columns of voxels normal or substantially normal to a surface of the article. The method further comprises selectively depositing layers of one or more build materials onto a substrate to form the article in accordance with the voxel data. In addition, at least one column of the plurality of columns of voxels exhibits a surface color resulting from a combination of colors of a plurality of voxels of the column.

Abstract: In one aspect, methods of printing a color 3D article are described herein. In some embodiments, a method described herein comprises receiving data representing a surface colorization of the article, and transforming the data representing the surface colorization of the article into voxel data of the article. The voxel data comprises (a) location values and at least one of (b) color values and (c) transparency values for a plurality of columns of voxels normal or substantially normal to a surface of the article. The method further comprises selectively depositing layers of one or more build materials onto a substrate to form the article in accordance with the voxel data. In addition, at least one column of the plurality of columns of voxels exhibits a surface color resulting from a combination of colors of a plurality of voxels of the column.

Abstract: In one aspect, methods of printing a color 3D article are described herein. In some embodiments, a method described herein comprises receiving data representing a surface colorization of the article, and transforming the data representing the surface colorization of the article into voxel data of the article. The voxel data comprises (a) location values and at least one of (b) color values and (c) transparency values for a plurality of columns of voxels normal or substantially normal to a surface of the article. The method further comprises selectively depositing layers of one or more build materials onto a substrate to form the article in accordance with the voxel data. In addition, at least one column of the plurality of columns of voxels exhibits a surface color resulting from a combination of colors of a plurality of voxels of the column.

Abstract: In one aspect, methods of printing a color 3D article are described herein. In some embodiments, a method described herein comprises receiving data representing a surface colorization of the article, and transforming the data representing the surface colorization of the article into voxel data of the article. The voxel data comprises (a) location values and at least one of (b) color values and (c) transparency values for a plurality of columns of voxels normal or substantially normal to a surface of the article. The method further comprises selectively depositing layers of one or more build materials onto a substrate to form the article in accordance with the voxel data. In addition, at least one column of the plurality of columns of voxels exhibits a surface color resulting from a combination of colors of a plurality of voxels of the column.

Abstract: A method measures distances between two printed lines on a rotating image receiving member to identify fluid drop mass or fluid drop velocity changes in inkjet ejectors in an inkjet printing system. An initial distance between the two lines is measured at the start of the operational life of the system. During the operation of the printing system, the lines are reprinted and the distance between the two lines compared to the initial distance stored in association with the printheads that printed the lines. If the distance has changed by more than a predetermined amount, a printer parameter is adjusted.

Abstract: A method measures distances between two printed lines on a rotating image receiving member to identify fluid drop mass or fluid drop velocity changes in inkjet ejectors in an inkjet printing system. An initial distance between the two lines is measured at the start of the operational life of the system. During the operation of the printing system, the lines are reprinted and the distance between the two lines compared to the initial distance stored in association with the printheads that printed the lines. If the distance has changed by more than a predetermined amount, a printer parameter is adjusted.

Abstract: A method measures distances between two printed lines on a rotating image receiving member to identify fluid drop mass or fluid drop velocity changes in inkjet ejectors in an inkjet printing system. An initial distance between the two lines is measured at the start of the operational life of the system. During the line of the printing system, the lines are reprinted and the distance between the two lines compared to the initial distance. If the distance has changed by more than a predetermined amount, a firing signal for the printheads that printed the lines is adjusted.

Abstract: A method measures distances between two printed lines on a rotating image receiving member to identify fluid drop mass or fluid drop velocity changes in inkjet ejectors in an inkjet printing system. An initial distance between the two lines is measured at the start of the operational life of the system. During the line of the printing system, the lines are reprinted and the distance between the two lines compared to the initial distance. If the distance has changed by more than a predetermined amount, a firing signal for the printheads that printed the lines is adjusted.

Abstract: A system detects image data in an image data stream that cause ink ejection errors and replaces the image data with a replacement pattern that attenuates the ink ejection errors.

Abstract: A system detects image data in an image data stream that cause ink ejection errors and replaces the image data with a replacement pattern that attenuates the ink ejection errors.

Abstract: A method of improving black print quality in a color printer having at least one color ink and black ink includes determining a location on a substrate where a black pixel is to be printed, printing a droplet of color ink at the location, and printing a droplet of black ink with the color droplet. If the color printer includes cyan, magenta and yellow, then a droplet of cyan ink, magenta ink or yellow ink may be printed with the droplet of black ink. For images containing black at a plurality of locations, the cyan, magenta and yellow droplets may be equally distributed among the plurality of locations. Alternatively, the cyan, magenta and yellow droplets may be distributed in accordance with a digital halftone screen.

Abstract: A method of printing including replacing each of black dots of a first subset of black dots of a bit map for a predetermined area with a process black dot, adding a non-black dot to each of black dots of a second subset of black dots of the bit-mapped data, and printing the bit map.

Abstract: A method of printing including changing each process black dot and each black plus non-black dot of a halftoned bit map to a black dot, if each of first and second adjacent dots on either side of such process black dot or black plus dot along a predetermined axis comprises a black dot, a black plus non-black dot, a process black dot, or a white dot, and printing the bit map.

Abstract: A method to compensate for dot placement errors includes receiving image data comprising a plurality of pixels, each having at least two states, a first corresponding to depositing no ink and a second corresponding to depositing ink; identifying a stray pixel pattern within the image data, the stray pixel pattern including a stray pixel corresponding to a misplaced dot in a dot pattern; and modifying the image data corresponding to the stray pixel pattern by setting the stray pixel to the first state and changing a second pixel from the first state to the second state.

Abstract: Disclosed is a phase change ink composition comprising (a) a phase change carrier, (b) a cyan colored resin or wax comprising the reaction product of (i) a cyan colorant having at least one functional group selected from (A) hydroxyl groups, (B) primary or secondary amino groups, (C) mercapto groups, or (D) mixtures thereof, and (ii) an isocyanate, and (c) an organic acid selected from (i) organic sulfonic acids, (ii) organic phosphinic acids, (iii) organic phosphonic acids, or (iv) mixtures thereof.

Abstract: Disclosed is a phase change ink composition comprising (a) a phase change carrier, (b) a cyan colored resin or wax comprising the reaction product of (i) a cyan colorant having at least one functional group selected from (A) hydroxyl groups, (B) primary or secondary amino groups, (C) mercapto groups, or (D) mixtures thereof, and (ii) an isocyanate, and (c) an organic acid selected from (i) organic sulfonic acids, (ii) organic phosphinic acids, (iii) organic phosphonic acids, or (iv) mixtures thereof.

Abstract: A method to compensate for dot placement errors includes receiving image data comprising a plurality of pixels, each having at least two states, a first corresponding to depositing no ink and a second corresponding to depositing ink; identifying a stray pixel pattern within the image data, the stray pixel pattern including a stray pixel corresponding to a misplaced dot in a dot pattern; and modifying the image data corresponding to the stray pixel pattern by setting the stray pixel to the first state and changing a second pixel from the first state to the second state.

Abstract: A method of improving black print quality in a color printer having at least one color ink and black ink includes determining a location on a substrate where a black pixel is to be printed, printing a droplet of color ink at the location, and printing a droplet of black ink with the color droplet. If the color printer includes cyan, magenta and yellow, then a droplet of cyan ink, magenta ink or yellow ink may be printed with the droplet of black ink. For images containing black at a plurality of locations, the cyan, magenta and yellow droplets may be equally distributed among the plurality of locations. Alternatively, the cyan, magenta and yellow droplets may be distributed in accordance with a digital halftone screen.

Abstract: An image transfer ink-jet printer employs an image receiving drum that rotates relative to an ink-jet array print head spanning the full width of the drum. A print head positioner moves the print head in precise increments to position adjacent scan lines of ink drops. Without affecting the overall scale of the image, adjacent pairs of scan lines are spaced at distances less than one nominal pixel width. Pairings within the range of 0.2 to 0.5 pixel widths are used, with optimal spacing at 0.35 pixel widths.