JPH03158882A - Magnetic recorder - Google Patents

Abstract

PURPOSE:To eliminate developing nonuniformity and to improve recording quality by detecting the viscosity of magnetic fluid, and controlling the viscosity of the magnetic fluid by receiving detection information. CONSTITUTION:The magnetic fluid 21 is always circulated with a circulating means 25. Unwanted matter included in the magnetic fluid is filtered with a filtering means 26 while being circulated. Therefore, the magnetic fluid 21 can be always kept at a cleaned state. Also, the flow rate of the magnetic fluid 21 in circulating is detected with a flow rate detector 27. A detection circuit 28 detects the viscosity of the magnetic fluid 21 based on the flow rate per unit time detected with the flow rate detector 27. A control circuit 29 controls the opening/closing state of a control valve 30 based on information from the detection circuit 28. For example, when the solvent of the magnetic fluid 21 is evaporated and the viscosity of the magnetic fluid 21 is increased, the control valve 30 is opened by receiving a signal from the control circuit 29. As a result, the solvent 23 in a housing container 24 flows out via the control valve 30, then, the viscosity of the magnetic fluid 21 can be kept constant.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic recording device that uses a magnetic fluid as a developer.

[Prior Art] A magnetic recording method is a method of visualizing a magnetic latent image formed on a magnetic layer using a magnetic material such as magnetic toner.

Since magnetic latent images have high resolution, magnetic recording methods are promising as a method for forming fine patterns.

However, when a magnetic toner is used as the magnetic material, a fine pattern commensurate with the magnetic latent image cannot be formed because the particle size of the magnetic toner is 10 micrometers or more.

To solve the above problem, magnetic recording devices using magnetic fluid as the magnetic material have been proposed (for example, Japanese Patent Laid-Open No. 60-480
Publication No. 63). The magnetic recording device disclosed in Japanese Patent Application Laid-Open No. 60-48063 immerses the surface of a magnetic drum on which a magnetic latent image is formed in a magnetic fluid, and sequentially visualizes the magnetic latent image while rotating the magnetic drum. It is something.

[Problems to be Solved] In the conventional magnetic recording device described above, the solvent of the magnetic fluid evaporates and its viscosity increases, which tends to cause uneven development.

An object of the present invention is to prevent uneven development by preventing the viscosity of the magnetic fluid from increasing, and to improve recording quality.

[Means for Solving the Problems] A magnetic recording device according to the present invention detects the viscosity of a magnetic fluid and receives the information to control the viscosity of the magnetic fluid.

[Example] Hereinafter, the present invention will be described in detail based on the accompanying drawings.

First, each component shown in the drawings will be explained.

11 is a magnetic layer, which is made of Fe2O3, Cr02, etc., Fe (iron), NI (nickel), Co (cobalt), etc.
The powder is dispersed in a resin.

Although not shown in the drawings, a protective layer may be provided on the surface of the magnetic layer 11.

Reference numeral 12 denotes a columnar or cylindrical base body, on the surface of which a magnetic layer 11 is formed, which rotates in the direction of the arrow.

The magnetic layer 11 and the base 12 make the magnetic drum 1
3 is composed.

A writing head 14 serves as a magnetic latent image forming means, and writes a magnetic pattern on the magnetic layer 11 to form a magnetic latent image.

A demagnetizing head 15 erases the magnetic latent image.

A cleaning blade 16 cleans the surface of the magnetic drum 13 by removing magnetic fluid (described later) and the like adhering to the surface of the magnetic drum 13.

17 is a recording medium, and transfer paper or the like is usually used.

Reference numeral 18 denotes a transfer roller, which sequentially transfers, onto the recording medium 17, a developed pattern formed by magnetic fluid corresponding to the magnetic latent image on the magnetic layer 11.

21 is a magnetic fluid, which is made by suspending ferromagnetic powder of about 10 nanometers in water or an organic solvent.

22 is a storage container that stores the magnetic fluid 21.

23 is a solvent for the magnetic fluid.

24 is a storage container that stores the solvent 23.

Reference numeral 25 denotes a circulation means, which circulates the magnetic fluid 21. The circulation means 25 is, for example, a motor that rotates blades.

A filtration means 26 filters out unnecessary substances contained in the circulating magnetic fluid.

27 is a flow rate detection device, which detects the flow rate of the magnetic fluid 21 during circulation. This flow rate detection device 27 includes:
For example, a differential pressure type can be used.

A detection circuit 28 detects the viscosity of the magnetic fluid 21 based on the flow rate per unit time detected by the flow rate detection device 27.

The flow rate detection device 27 and the detection circuit 28 constitute a detection means.

Reference numeral 29 denotes a control circuit, which controls the opening/closing state of a control valve 30, which will be described later, based on information from the detection circuit 28.

Reference numeral 30 denotes a control valve, which opens and closes based on a signal from the control circuit 29.

The control circuit 29 and the control valve 30 constitute a control means.

Next, the operation of this embodiment will be explained.

First, a series of operations such as formation and transfer of a magnetic latent image will be explained.

A predetermined magnetic pattern is sequentially written into the magnetic layer 11 by a write head 14 to form a magnetic latent image. When the magnetic drum 13 rotates and the magnetic latent image portion is immersed in the magnetic fluid 21, the magnetic fluid adheres to the surface of the magnetic drum 13 on which the magnetic latent image is formed due to magnetic force, and development is performed. In the portion where the magnetic latent image is not formed, no magnetic force acts between the magnetic fluid 21 and the magnetic fluid 21, so that the magnetic fluid does not adhere. The developed pattern of the magnetic fluid adhered to the surface of the magnetic drum 13 is transferred onto the recording medium 17 by the transfer roller 18 . When the transfer operation is completed, the magnetic latent image is transferred to the demagnetizing hand 15.
It is erased by When the degaussing operation is completed, the cleaning blade 16 removes the magnetic fluid and the like adhering to the surface of the magnetic drum 13, thereby cleaning the surface of the magnetic drum 130.

In this manner, a series of magnetic recording cycles is completed.

Next, the operation of circulating the magnetic fluid 21 and the operation of keeping the viscosity of the magnetic fluid 21 constant will be explained.

The magnetic fluid 21 is constantly circulated by a circulation means 25.

Unwanted substances contained in the magnetic fluid are filtered by the filtering means 26 during circulation. Therefore, the magnetic fluid 21 is always kept clean. Further, the flow rate of the magnetic fluid 21 during circulation is detected by a flow rate detection device 27. The detection circuit 28 detects the viscosity of the magnetic fluid 21 based on the flow rate per unit time detected by the flow rate detection device 27. The control circuit 29 controls the open/close state of the control valve 30 based on information from the detection circuit 28. For example, when the solvent of the magnetic fluid 21 evaporates and the viscosity of the magnetic fluid 21 increases, the control valve 30 opens in response to a signal from the control circuit 29 .

As a result, the solvent 23 in the storage container 24 is transferred to the control valve 30.
The viscosity of the magnetic fluid 21 is kept constant.

[Effect] In the magnetic recording device according to the present invention, the viscosity of the magnetic fluid can always be maintained at an optimum state by detecting and controlling the viscosity of the magnetic fluid. As a result, uneven development is reduced,
Recording quality can be improved.

[Brief explanation of the drawing]

The figure is an explanatory diagram showing an embodiment of the present invention. 11... Magnetic layer 14... Write head (magnetic latent image forming means) 27.
...Viscosity detection device 28...Detection circuit 29...Control circuit 30...Control valve

Claims (1)

[Scope of Claims] A magnetic latent image forming means for forming a magnetic latent image on a magnetic layer, a developing means for developing the magnetic latent image using a magnetic fluid, and a detecting means for detecting the viscosity of the magnetic fluid. and a control means for controlling the viscosity of the magnetic fluid in response to information from the detection means.