Resin ink jet filter and method of manufacturing the same

Claim 2

A filter according to claim 1, wherein the pores are formed on the basis of microballoons each comprising a core composed of a material capable of expanding and vaporizing at a temperature which is higher than room temperature, said core being contained in a shell composed of a thermosetting resin as a main component.

Claim 3

A filter according to claim 2, wherein the core material is composed of a material selected from the group consisting of iosobutane and isobutylene.

Claim 4

A filter according to claim 2, wherein the thermosetting resin contains as a main constituent at least a component selected from the group consisting of polyvinyl chloride, polyvinylidene chloride, vinyl chloride-vinyl chloride copolymer, acrylonitrile-vinyl chloride copolymer, and vinyl acetate-vinyl chloride copolymer.

Claim 5

A filter according to claim 1, wherein the activation energy-setting resin is a hardening resin which can be hardened with the action of thermal energy or light energy.

Claim 6

A filter according to claim 1 which has a thickness of 5 times or more the diameter of the pore in parallel to the direction of a liquid to be supplied.

Claim 7

A filter according to claim 1 which is used in a part of an ink supply path of an ink jet apparatus.

Claim 8

An ink jet head comprising an ink discharging outlet; a substrate for said ink jet head including an electrothermal converting body comprising a heat generating resistor for generating thermal energy for discharging ink from said discharging outlet, and wirings electrically connected to said heat generating resistor so that said wirings can supply an electric signal for generating said thermal energy to said heat generating resistor; and an ink supply system for supplying ink, characterized in that a filter is disposed in a part of said ink supply system, said filter comprising a number of pores formed in a hardened resin layer, said pores being communicated with each other so that liquid can pass through said resin layer.

Claim 9

An ink jet head according to claim 8, wherein the pores are formed on the basis of microballoons each comprising a core composed of a material capable of expanding and vaporizing at a temperature which is higher than room temperature, said core being contained in a shell composed of a thermosetting resin as a main component.

Claim 10

An ink jet head according to claim 9, wherein the core material is composed of a material selected from the group consisting of iosobutane and isobutylene.

Claim 11

An ink jet head according to claim 9, wherein the thermosetting resin contains as a main constituent at least a component selected from the group consisting of polyvinyl chloride, polyvinylidene chloride, vinyl chloride-vinyl chloride copolymer, acrylonitrile-vinyl chloride copolymer, and vinyl acetate-vinyl chloride copolymer.

Claim 12

An ink jet head according to claim 8, wherein the activation energy-setting resin is a hardening resin which can be hardened with the action of thermal energy or light energy.

Claim 13

An ink jet head according to claim 8, wherein the pores are of 30 um or less in mean diameter.

Claim 14

An ink jet head according to claim 8 which has a thickness of 5 times or more the diameter of the pore in parallel to the direction of ink to be supplied.

Claim 15

A process for producing a filter for the filtration of a liquid, comprising the steps of: dispersing a number of microballoons each having a shell constituted by a solvent-soluble resin in an activation energy setting resin to obtain a dispersion, subjecting said dispersion to heat treatment to expand each of the microbaloons, hardening the activation energy setting resin, treating the resultant with a solvent having a selective solubility to only the shell of each of the microballoons to remove all the shells of the microballoons whereby pores formed on the basis of the microballoons are communicated with each other.

Claim 16

The process for producing a filter according to claim 15, wherein the microballoons comprise respectively a core composed of a material capable of expanding and vaporizing at a temperature which is higher than room temperature, said core being contained in a shell composed of a thermosetting resin as a main component.

Claim 17

The process for producing a filter according to claim 16, wherein the core material is composed of a material selected from the group consisting of iosobutane and isobutylene.

Claim 18

The process for producing a filter according to claim 16, wherein the thermosetting resin contains as a main constituent at least a component selected from the group consisting of polyvinyl chloride, polyvinylidene chloride, vinyl chloride-vinyl chloride copolymer, acrylonitrile-vinyl chloride copolymer, and vinyl acetate-vinyl chloride copolymer.

Claim 19

The process for producing a filter according to claim 15, wherein the activation energy-setting resin is a hardening resin which can be hardened with the action of thermal energy or light energy.

Claim 20

The process for producing a filter according to claim 15, wherein the filter produced has a thickness of 5 times or more the diameter of the pore in parallel to the direction of a liquid to be supplied.

Claim 21

The process for producing a filter according to claim 15, wherein the content of the microballoons in the activation energy setting resin is 20 to 90 wt.%.

Claim 22

The process for producing a filter according to claim 15, wherein the selective solubility-bearing solvent is selected from the group consisting of acetone and dimethylformamide.

Claim 23

The process for producing a filter according to claim 15, wherein the filter produced is used in a part of an ink supply path of an ink jet apparatus.

Claim 24

A process for producing an ink jet head, said process comprises the steps of: (a) providing a substrate for an ink jet head, including an electrothermal converting body comprising a heat generating resistor for generating thermal energy for discharging ink, and wirings electrically connected to said heat generating resistor so that said wirings can supply an electric signal for generating said thermal energy to said heat generating resistor; (b) forming a removable solid layer at a portion corresponding to an ink flow path system comprising an ink discharging outlet, ink pathway, common liquid chamber and ink supply port on said substrate; (c) laminating a covering material so as to cover said substrate and said solid layer; (d) removing said solid layer to form an ink flow path system; (e) forming a layer composed of a dispersion comprising a number of microballoons each being encapsulated by a shell made of a solvent soluble resin dispersed in an activation energy setting resin in at least a part of said ink flow path system; (f) subjecting the layer formed in the step (e) to heat treatment to expand each of the microballoons and hardening the activation energy setting resin, and (g) subjecting the dispersion layer treated in the step (f) to treatment with a solvent having a selective solubility to only the shells of the microballoons to remove the shells of the microballoons, whereby pores based on the microbaloons are communicated with each other to form a filter.

Claim 25

The process for producing an ink jet head according to claim 24, wherein the microballoons comprise respectively a core composed of a material capable of expanding and vaporizing at a temperature which is higher than room temperature, said core being contained in a shell composed of a thermosetting resin as a main component.

Claim 26

The process for producing an ink jet head according to claim 25, wherein the core material is composed of a material selected from the group consisting of iosobutane and isobutylene.

Claim 27

The process for producing an ink jet head according to claim 25, wherein the thermosetting resin contains as a main constituent at least a component selected from the group consisting of polyvinyl chloride, polyvinylidene chloride, vinyl chloride-vinyl chloride copolymer, acrylonitrile-vinyl chloride copolymer, and vinyl acetate-vinyl chloride copolymer.

Claim 28

The process for producing an ink jet head according to claim 24, wherein the activation energy-setting resin is a hardening resin which can be hardened with the action of thermal energy or light energy.

Claim 29

The process for producing an ink jet head according to claim 24, wherein the filter formed has a thickness of 5 times or more the diameter of the pore in parallel to the direction of a liquid to be supplied.

Claim 30

The process for producing an ink jet head according to claim 24, wherein the content of the microballoons in the activation energy setting resin is 20 to 90 wt.%.

Claim 31

The process for producing an ink jet head according to claim 24, wherein the selective solubility-bearing solvent is selected from the group consisting of acetone and dimethylformamide.