Elastic members for inkjet recording apparatus ink tanks and inkjet recording apparatus

4 The elastic member for an ink jet recording apparatus as described in claim 1 or 2, used as a sealing member for an ink tank which is disposed in an ink feeding port in the ink tank and prevents an ink from leaking from the above ink feeding port.

5 The elastic member for an ink jet recording apparatus as described in claim 1 or 2, disposed in an ink jet recording apparatus body and used as a sealing member

7 An ink jet recording apparatus, characterized by using the elastic member as described in any of claims 1 to 5.

8 The ink jet recording apparatus as described in claim 7, having a performance of 360 dpi×360 dpi (dot/inch) or more.

9 The ink jet recording apparatus as described in claim 7 or 8, using a color ink having 5 or more colors.

An elastic member for an ink jet recording apparatus in which an ink is fed to record printed letters on a recording medium, characterized by being constituted from a thermoplastic elastomer composition in which a network structure having a pore diameter of 50 μm or less is formed, comprising:

• (a) 100 parts by weight of a hydrogenated block copolymer obtained by hydrogenating a block copolymer which comprises three polymer blocks, in which polymer blocks at both ends out of the above three polymer blocks are polymers block comprising principally a vinyl aromatic compound and in which a polymer block present between the polymer blocks at the above both ends is a polymer block comprising principally a conjugate diene compound, wherein a weight average molecular weight measured by gel permeation chromatography (GPC) is 200,000 or more,
• (b) 60 to 170 parts by weight of a softening agent for a non-aromatic rubber having a dynamic viscosity of 300 to 500 mm2/sec at 40° C. and
• (c) 5 to 30 parts by weight of crystalline polyolefin.

16 An ink jet recording apparatus, characterized by using the elastic member as described in any of claims 10 to 14.

17 The ink jet recording apparatus as described in claim 16, having a performance of 360 dpi X 360 dpi (dot/inch) or more.

18 The ink jet recording apparatus as described in claim 16 or 17, using a color ink having 5 or more colors.

19 An elastic member used for an ink jet recording apparatus in which an ink is fed to record printed letters on a recording medium, characterized by being constituted from a thermoplastic elastomer composition in which a shear rate dependency of a melt viscosity measured by means of a capillograph is −1.5 to −0.8, comprising:

• (a) 100 parts by weight of a hydrogenated block copolymer obtained by hydrogenating a block copolymer which comprises three polymer blocks, in which polymer blocks at both ends out of the above three polymer blocks are polymer blocks comprising principally a vinyl aromatic compound and in which a polymer block present between the polymer blocks at the above both ends is a polymer block comprising principally a conjugate diene compound, wherein a weight average molecular weight measured by gel permeation chromatography (GPC) is 200,000 or more,
• (b) 60 to 170 parts by weight of a softening agent for a non-aromatic rubber having a dynamic viscosity of 300 to 500 mm2/sec at 40° C. and
• (c) 5 to 30 parts by weight of crystalline polyolefin.

The elastic member for an ink jet recording apparatus as described in claim 19, wherein the polymer blocks at both ends in the component (a) comprise polystyrene, and the crystalline polyolefin in the component (c) comprises polypropylene.

25 An ink jet recording apparatus, characterized by using the elastic member as described in any of claims 19 to 23.

26 The ink jet recording apparatus as described in claim 25, having a performance of 360 dpi×360 dpi (dot/inch) or more.

27 The ink jet recording apparatus as described in claim 25 or 26, using a color ink having 5 or more colors.