Filling liquid

Abstract

In a droplet ejection apparatus for forming a conductive pattern with a conductive pattern formation ink comprised of a water-based dispersion medium and metal particles dispersed in the water-based dispersion medium by an ink jet method, the droplet ejection apparatus includes a droplet ejection head having a reservoir with ink chambers for storing the conductive pattern formation ink and a plurality of nozzles from which droplets of the conductive pattern formation ink are to be ejected by the ink jet method. A filling liquid is used instead of the conductive pattern formation ink for filling the reservoir and the ink chambers to prevent the reservoir and the ink chambers from being dried when the droplet ejection apparatus is not used for a certain period of time. The filing liquid is comprised of the water-based dispersion medium, a sugar alcohol A and a surfactant A. The filling liquid can be easily and reliably replaced with the conductive pattern formation ink.

1 . In a droplet ejection apparatus for forming a conductive pattern with a conductive pattern formation ink comprised of a water-based dispersion medium and metal particles dispersed in the water-based dispersion medium by an ink jet method, the droplet ejection apparatus including a droplet ejection head having a reservoir with ink chambers for storing the conductive pattern formation ink and a plurality of nozzles from which droplets of the conductive pattern formation ink are to be ejected by the ink jet method, wherein a filling liquid is used instead of the conductive pattern formation ink for filling the reservoir and the ink chambers to prevent the reservoir and the ink chambers from being dried when the droplet ejection apparatus is not used for a certain period of time,
 wherein the filing liquid is comprised of the water-based dispersion medium, a sugar alcohol A and a surfactant A.   
   
   
       2 . The filling liquid as claimed in  claim 1 , wherein the conductive pattern formation ink further comprises a sugar alcohol B, wherein the sugar alcohol A contained in the filling liquid includes the same kind of sugar alcohol as a kind of the sugar alcohol B contained in the conductive pattern formation ink. 
   
   
       3 . The filling liquid as claimed in  claim 1 , wherein the conductive pattern formation ink further comprises a surfactant B, and the surfactant B is constituted of components, wherein the surfactant A contained in the filling liquid includes at least a part of the components constituting the surfactant B contained in the conductive pattern formation ink. 
   
   
       4 . The filling liquid as claimed in  claim 1 , wherein the sugar alcohol A includes at least one of xylitol and sorbitol. 
   
   
       5 . The filling liquid as claimed in  claim 1 , wherein an amount of the sugar alcohol A contained in the filling liquid is in the range of 3 to 25 wt %. 
   
   
       6 . The filling liquid as claimed in  claim 1 , wherein a hydrophile lipophile balance (HLB) of the surfactant A is in the range of 8 to 16. 
   
   
       7 . The filling liquid as claimed in  claim 1 , wherein the surfactant A includes an acetylene glycol-based compound. 
   
   
       8 . The filling liquid as claimed in  claim 7 , wherein the acetylene glycol-based compound has an acetylene group, and a bilateral symmetry structure in which the acetylene group is placed at the center. 
   
   
       9 . The filling liquid as claimed in  claim 1 , wherein an amount of the surfactant A contained in the filling liquid is in the range of 0.05 to 5 wt %. 
   
   
       10 . The filling liquid as claimed in  claim 1  further comprising hydroxyl acid or a salt of the hydroxyl acid having three or more COOH and OH groups in total, wherein a number of the COOH groups is equal to or greater than a number of the OH group(s). 
   
   
       11 . The filling liquid as claimed in  claim 1  further comprising mercapto acid or a salt of the mercapto acid having two or more COOH and SH groups in total. 
   
   
       12 . The filling liquid as claimed in  claim 1 , wherein surface tension of the filling liquid is in the range of 20 to 50 dyn/cm, wherein the surface tension of the filling liquid is equal to or smaller than surface tension of the conductive pattern formation ink.