Disclosed is a pen for writing, referred to as a palm pen herein because the body of the pen fits into the palm of a human hand. The palm pen can include a spherically shaped body, and an ink delivery system. The ink delivery system can include a tip having an end connected to the body and an opposite end comprising a nib, an ink conduit having an end coupled to the nib within the tip and an opposite end extending inside the body, and a first ink cartridge fluidly coupled with the opposite end of the ink conduit and contained within the body. The ink delivery system can additionally include a cartridge holder having an active cartridge slot for the first ink cartridge and cartridge storage slots for storage of additional ink cartridges.

A fluid application device including a reservoir intended to contain a free fluid and a fluid delivery device, wherein the reservoir is sealed by a valve having a self-healing material. The fluid application device includes a tubular means for piercing the valve and for simultaneously placing fluid from the reservoir in communication with the fluid delivery device.

An applicator includes a valve mechanism that communicates an application liquid tank and an applying part. The valve mechanism has at least a valve stem and a valve holder for holding the valve stem therein, the application liquid can flow through a gap between the valve stem and the valve holder, the valve stem is formed with an air exchange hole, and, the air exchange hole can be opened and closed by an opening/closing member that opens/closes when the pressure on the application liquid tank side becomes negative or positive compared to that on the applying part side. The applicator is capable of exchanging air after discharging the application liquid even if the applicator is equipped with a valve mechanism that opens its valve by increasing the internal pressure of the ink tank.

Disclosed is a pen for writing, referred to as a palm pen herein because the body of the pen fits into the palm of a human hand. The palm pen can include a spherically shaped body, and an ink delivery system. The ink delivery system can include a tip having an end connected to the body and an opposite end comprising a nib, an ink conduit having an end coupled to the nib within the tip and an opposite end extending inside the body, and a first ink cartridge fluidly coupled with the opposite end of the ink conduit and contained within the body. The ink delivery system can additionally include a cartridge holder having an active cartridge slot for the first ink cartridge and cartridge storage slots for storage of additional ink cartridges.

To provide an applicator capable of exchanging air after discharging the application liquid even if the applicator is equipped with a valve mechanism that opens its valve by increasing the internal pressure of the ink tank.

An applicator includes a valve mechanism that communicates an application liquid tank and an applying part. The valve mechanism has at least a valve stem and a valve holder for holding the valve stem therein, the application liquid can flow through a gap between the valve stem and the valve holder, the valve stem is formed with an air exchange hole, and, the air exchange hole can be opened and closed by an opening/closing member that opens/closes when the pressure on the application liquid tank side becomes negative or positive compared to that on the applying part side.

Disclosed is a pen for writing, referred to as a palm pen herein because the body of the pen fits into the palm of a human hand. The palm pen can include a spherically shaped body, and an ink delivery system. The ink delivery system can include a tip having an end connected to the body and an opposite end comprising a nib, an ink conduit having an end coupled to the nib within the tip and an opposite end extending inside the body, and a first ink cartridge fluidly coupled with the opposite end of the ink conduit and contained within the body. The ink delivery system can additionally include a cartridge holder having an active cartridge slot for the first ink cartridge and cartridge storage slots for storage of additional ink cartridges.

A writing instrument includes: a replacement ink cartridge including a bottomed cylindrical container that has an opened front end and a closed rear end and a plug fitted into an inner circumferential surface of an opening of the container; and a projection inserted into the opening of the container to press the plug rearward, thereby opening the plug of the ink cartridge, wherein the projection and the plug are fitted when the plug is press opened, and when the cartridge is replaced, the fitting between the projection and the plug is released and the plug is locked again in the opening of the container.

A writing instrument includes: a writing instrument body and an ink cartridge. The ink cartridge includes a bottomed cylindrical container with an opened front end and a plug fitted into an inner circumferential surface of an opening of the container. The writing instrument body includes a projection that opens the ink cartridge when inserted into the opening to press the plug rearward and an air tight connecting portion, formed separately from the projection, that surrounds the projection. The opening is divided into a plurality of openings by air tight fitting the opening in the air tight connecting portion. A plurality of longitudinal channels are formed on an outer periphery of the projection. At least one of the plurality of channels serves as an ink channel and at least one of the other channels serves as an air intake path.

Disclosed is a device for encoding information written on a readable surface, the device including a device housing containing at least one ink reservoir, an ink dispensing tip in communication with said at least one ink reservoir; and ink stored in the at least one ink reservoir and configured to flow from the ink dispensing tip, the ink being encodable to include supplemental encoded information, the supplemental encoded information being detectable by at least one detecting sensor when dispensed on the readable surface, wherein the readable surface is any surface that will accept the ink.

Disclosed is a device for encoding information written on a readable surface, the device including a device housing containing at least one ink reservoir, an ink dispensing tip in communication with said at least one ink reservoir; and ink stored in the at least one ink reservoir and configured to flow from the ink dispensing tip, the ink being encodable to include supplemental encoded information, the supplemental encoded information being detectable by at least one detecting sensor when dispensed on the readable surface, wherein the readable surface is any surface that will accept the ink.