JPH04367862A - Production of microcapsule - Google Patents

Abstract

PURPOSE:To simply and rapidly produce microcapsules contg. a first component such as a dye, a pigment and a dye precursor which discolors by a reaction with a developer and a second component which cures under energy from the outside. CONSTITUTION:A mixture of a dye precursor with an acrylic photo- polymerizable substance, a photopolymn. initiator and a microcapsule wall material (A) is emulsified in water mixed with a surfactant and the resulting emulsion is added to an aq. soln. of a microcapsule wall material (B) to produce microcapsules contg. a first component such as the dye precursor and a second component which cures under energy from the outside.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a microcapsule and an image forming apparatus using the microcapsule.

0002

[Prior Art] Conventionally, a photosensitive sheet coated with microcapsules encapsulating a dye precursor, a photocurable substance, etc. is exposed to light using an exposure means based on image information, and the microcapsules are exposed based on the image information. After hardening, the microcapsules that did not harden were developed under pressure while in close contact with a support such as plain paper coated with a color developer that changed color by reacting with the dye precursor encapsulated in the microcapsules. An image forming apparatus has been put into practical use that forms an image by reacting a dye precursor that is crushed with a crushing roller and flows out from a microcapsule with a color developer.

0003

[Problems to be Solved by the Invention] However, the microcapsules used in conventional image forming apparatuses are mainly produced by the coacervation method, and it is difficult to control the temperature and pH of the solution. Capsule production took a long time.

The present invention has been made to solve the above-mentioned problems, and its object is to easily produce microcapsules encapsulating dye precursors and the like in a short period of time.

[0005]

[Means for Solving the Problems] In order to achieve this object, the method for producing microcapsules of the present invention provides a method for producing microcapsules using a first dye precursor, etc., which changes color by reacting with a dye, pigment, etc., or a color developer, etc.
Microcapsules containing at least the component and a second component that hardens upon receiving external energy are produced using an interfacial polymerization method.

[0006]

[Function] In the microcapsule manufacturing method of the present invention, a first component such as a dye precursor that changes color by reacting with dyes, pigments, etc. and color developers, etc., and a second component that hardens upon receiving energy from the outside. Microcapsules encapsulating can be easily produced in a short time.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment embodying the present invention will be described below with reference to the drawings.

FIG. 1 shows an enlarged cross-sectional view of the microcapsule of the present invention. The microcapsule 1 consists of an outer shell 2 and a liquid component 3 inside thereof.

The liquid component 3 includes at least a photocurable substance that cures in response to a predetermined wavelength, and a dye precursor that develops color by reacting with a color developer.

The photocurable substances include polymerizable compounds, such as N-vinyl-2-pyrrolidone, bisphenol A diacrylate and methacrylate, tripropylene glycol diacrylate and methacrylate, polyethylene glycol diacrylate and methacrylate, and pentyl diacrylate and methacrylate. Examples include erythritol triacrylate and methacrylate, dipentaerythritol hexaacrylate and methacrylate, trimethylolpropane triacrylate and methacrylate, oligoester acrylate and methacrylate, and the like. Further, these polymerizable compounds may be used alone or in combination of two or more. Usually, these polymerizable compounds and a photopolymerization initiator are used in combination. The photopolymerization initiator is one that is sensitive to light and initiates polymerization of the resin, and includes, for example, benzophenone, benzoyl alkyl ethers such as benzoyl isopropyl ether, Michler's ketone, metal arene compounds, 2,4-diethylthioxanthone, etc. Can be done.

Dye precursors include diphenylmethane compounds, triphenylmethane compounds, bisphenylmethane compounds, xanthene compounds, thiazine compounds,
Fluoran compounds, spiropyran compounds, etc., and mixtures thereof are used.

Next, a method for manufacturing the microcapsule 1 will be explained. The following microcapsule manufacturing method uses an interfacial polymerization method, so unlike the coacervation method, there is no need to adjust the pH or temperature, and all processes can be performed at room temperature and normal pressure. Microcapsules can be obtained in a short time. For comparison, FIG.
Shown below.

[0013] A method for producing microcapsules using an interfacial polymerization method.

Example 1. A method for manufacturing microcapsules whose outer shell is made of polyamide will be described.

As core material monomers, polyethylene glycol diacrylate (M240 manufactured by Toagosei Co., Ltd.) and dipentaerythol hexaacrylate (M240 manufactured by Toagosei Co., Ltd.) were used.
400) in a ratio of 3:4, 1.5 parts by weight of an iron arene compound, 0.5 parts by weight of a triphenylmethane compound, and 2.5 parts by weight of terephthaloyl dichloride. .

50 ml of a 20% aqueous solution of polyoxyethylene sorbitan tristearate (Rheodol TW-S320 manufactured by Kao Soap Co., Ltd.) was added to the core material monomer, and 3
Stir at 000-5000 rpm to emulsify.

1% aqueous solution of hexamethylene diamine 150
ml of the emulsified solution at once while stirring. Immediately, an interfacial polymerization reaction occurs, and microcapsules 1 having an outer shell made of polyamide are produced.

FIG. 3 shows a flowchart of the above method.

Example 2. A method for manufacturing microcapsules whose outer shell is made of polyester will be described.

Hexamethylenediamine 1 of Example 1 above
% aqueous solution, a 1% diethylene glycol aqueous solution is used.

Although two types of microcapsule manufacturing methods have been shown, the present invention is not limited to these.

An image forming apparatus using microcapsules configured as described above will be explained. In the image forming apparatus described below, it is necessary to manufacture three types of microcapsules using three types of dye precursors that react with a color developer to develop yellow, magenta, and cyan colors, respectively.

FIG. 4 shows a schematic cross-sectional view of an image forming apparatus 40 using the microcapsules 1 described above. The image forming apparatus 40 is roughly divided into four units. That is, an exposure device 41 that exposes the original 45 to the microcapsule paper 44, a developer coating device 20 that applies the developer 11 to the exposed microcapsule paper 44, and a microcapsule paper after the developer has been applied. 44 and plain paper 10 to develop color and form a color image on the plain paper 10; It also includes a heat fixing device 49 for fixing the image. The exposure device 41 is located at the top of the image forming device 40, and the heat fixing device 49 is located at the bottom. Further, the microcapsule coating device 20 is provided on the right side in FIG. 4, and the pressure developing device 47 is provided approximately at the center of the image forming device 40.

The exposure device 41 includes a halogen lamp 50.
A document table 52 is provided below the halogen lamp 50.
is provided. The original 45 is placed on the original platen 52, and the microcapsule paper 44 pulled out from the paper feed roll 42 is exposed through the original 45. The document table 5
Guide rollers 53 and 54 are provided on the right side of 2 and above the pressure developing device 47, and the exposed microcapsule paper 44 passes through the guide roller 53, the developer coating device 20, and the pressure developing device 47. , take-up roll 4
It is wound up in 3.

The color developer application device 20 includes a hopper 12 storing a powdery color developer 11, and a color developer carrying roller 13 provided within the hopper 12 and supporting the color developer 11.
In addition, the developer supply roller 14 is provided auxiliary to make the developer carrying roller 13 carry the developer 11, and the developer 11 is not carried excessively on the developer carrying roller 13. It is composed of a layer regulating blade 15. Further, a counter electrode roller 16 is provided on the left side of the developer carrying roller 13 with a predetermined gap d therebetween, and a DC power source E for applying a high voltage is connected to the counter electrode roller 16. There is. The color developer carrying roller 13 and the color developer supplying roller 14 are both grounded.

A support cassette 17 in which plain paper 10 is stored is provided below the developer coating device 20, and the plain paper 10 is fed by a feed roller 18 from an upper opening of the support cassette 17. The microcapsule paper 4 coated with the color developer 11 passes through the guide roller 54.
It is configured to be inserted into the pressure developing device 47 in close contact with 4.

The pressure developing device 47 has a gap of about 1 cm between the rollers.
It is composed of a set of pressure rollers 55 to which a pressure of t is applied, and an image is formed and transferred onto the plain paper 10 here. The microcapsule paper 44 that has passed through the pressure development device 47 and the plain paper 10 on which the image has been formed are separated by guide rollers 56, 56 provided below the pressure development device 47, and the microcapsule paper 44 is rolled up. Take roll 4
The plain paper 10 on which the image has been formed is conveyed to a heat fixing device 49.

The heat fixing device 49 is provided with a heat source 51 that can maintain the temperature at about 140° C., and the heat fixing device 49 is equipped with a heat source 51 that can maintain the temperature at about 140° C.
By applying heat to the 0, the fixing action of the image is performed.

The microcapsule paper 44 is made by placing the microcapsules 1 produced by the above method on a film 4 made of polyethylene terephthalate, polyimide, etc., and placing them on a film 4 made of polyvinyl alcohol, sodium polyacrylate, polyethylene oxide, etc., as shown in FIG. methylcellulose,
It has a structure in which it is coated using a binder 5 such as polyamide, polyethylene, polyethylene chloride, vinyl chloride, or epoxy acrylate.

Next, the operation of this device will be explained.

By pressing the start button of the image forming apparatus 40 (not shown), the halogen lamp 50 is turned on, and an image is exposed onto the microcapsule paper 44 through the document 45 placed on the document table 52. After the exposure, the microcapsule paper 44 passes through the guide roller 53, and then the developer 11 is electrostatically applied onto the microcapsule paper 44 by the developer coating device 20 at the electrode roller 16, and then the microcapsule paper 44 is transferred to the pressure developing device 47. will be transported to the location.

On the other hand, the plain paper 10 is also taken out from the support cassette 17 by the feed roller 18 and transferred to the pressure developing device 47.
The plain paper 10 and the microcapsule paper 44 coated with the color developer 11 are transported by the guide roller 54 to
The superimposed state is sent to the pressure developing device 47. Thereafter, pressure development is performed by a pressure roller 55, and the dye precursor substance contained in the microcapsules reacts with the color developer, so that a color image is formed and transferred onto the plain paper 10. After the color image has been formed on the plain paper 10 by the pressure developing device 47, the image is fixed by the heat fixing device 49, and the paper passes through the guide roller 57 and is discharged to the outside. Further, the microcapsule paper 44 that has passed through the pressure developing device 47 is wound up by a winding roll 43.

It should be noted that the present invention is not limited to the embodiments described above, and can be modified without departing from the spirit thereof.

For example, in this embodiment, the color developer was applied to the microcapsule paper, but the color developer may be applied to plain paper and then developed with the microcapsule paper.

[0035]

[Effect of the invention] As is clear from the above explanation,
In the method for producing microcapsules of the present invention, dyes,
Microcapsules encapsulating a first component such as a dye precursor that changes color by reacting with pigments, color developers, etc., and a second component that hardens upon receiving external energy can be easily and quickly produced. It is possible to manufacture.

[Brief explanation of drawings]

FIG. 1 is an enlarged sectional view of an embodiment of a microcapsule according to the first invention.

FIG. 2 is a diagram showing a method for producing microcapsules using a coacervation method.

FIG. 3 is a diagram showing a method for producing microcapsules of the present invention using an interfacial polymerization method.

FIG. 4 is a schematic cross-sectional view of an image forming apparatus using microcapsules manufactured by the manufacturing method of the present invention.

FIG. 5 is a partially enlarged view of microcapsule paper used in an image forming apparatus.

[Explanation of symbols]

1 Microcapsule 2 Outer part 3. Liquid component 20 Color developer coating device 40 Image forming device 41 Exposure device 47 Pressure developing device 49 Heat fixing device

Claims (1)

[Claims] 1. Microcapsules in which at least a first component such as a dye precursor that changes color by reacting with a dye, pigment, or developer, and a second component that hardens upon receiving energy from the outside are encapsulated. A microcapsule characterized in that an interfacial polymerization reaction is used as a microcapsule manufacturing method.