Cleaning and liquid contact with solids – Processes – Including application of electrical radiant or wave energy...
Reexamination Certificate
2000-04-06
2001-10-02
Markoff, Alexander (Department: 1746)
Cleaning and liquid contact with solids
Processes
Including application of electrical radiant or wave energy...
C134S016000, C134S017000, C134S038000, C134S042000
Reexamination Certificate
active
06296713
ABSTRACT:
BACKGROUND OF THE INVENTION
1) Field of the Invention
The present invention relates to an erasing method of erasing a recording agent on a recording surface of a recording medium recorded by a recording agent composed of a near IR erasable dye, for example, an aqueous ink, an oily ink, toner, etc., and an erasing apparatus for performing that erasing method.
2) Description of the Related Art
In recent years, near IR erasable dyes have been coming under attention as dyes of the recording paper used in various printers, copying machines, etc. This is because a repeated reuse of the recording medium such as recording paper recorded by such a recording agent is possible, and this can contribute to the conservation of forest resources. As disclosed in for example Japanese Unexamined Patent Publication (Kokai) No. 4-362935, a near IR erasable dye is a complex compound of a near IR absorbing cationic dye-boron anion. This compound is decomposed by irradiation of near infrared rays (a wavelength of 700 nm or more) to become a transparent substance, but is a relatively stable compound under visible rays. Accordingly, it is possible to utilize the near IR erasable dye as a recording agent in various printers etc., for example, various dyes of inks and toners, whereby the recording agent on the recording paper can be decomposed and erased by the irradiation of the near infrared rays, therefore making reuse of the recording paper possible.
So as to achieve an enhancement of the efficiency of reuse of recording paper, it is necessary to quickly and effectively carry out processing for decomposition of the near IR erasable dye, that is, processing for erasing of the recording agent. The decomposition of the near IR erasable dye is promoted under the presence of an appropriate catalyst, for example, tetrabutyl ammonium butyl triphenyl borate. In the above-mentioned Japanese Unexamined Patent Publication (Kokai) No. 4-362935, as the recording agent composed of the near IR erasable dye and the catalyst (sensitizing agent), an ink or a toner has been proposed, and such a near IR erasable dye included in the recording agent is smoothly decomposed due to such a catalyst at the time of irradiation of near infrared rays, therefore a quick erasing processing of the recording agent, that is, an enhancement of efficiency of reuse of. the recording paper, can be achieved.
Also, natural light or room light includes light having a wavelength of 700 nm or more, therefore where the recording paper recorded by a catalyst-containing recording agent is left to stand for a long period, the recording density on the recording paper, that is, the printing density, is gradually lowered due to the catalyst. Therefore, arises a problem on the point of persistency of such a recording paper. Moreover, it is pointed out that there is a problem that, where the printing density is once lowered in this way, even if the irradiation of near infrared rays is positively carried out to that recording agent, complete erasure cannot be carried out.
On the other hand, it is known also that the erasability of the recording agent as mentioned above is promoted under a high temperature, and therefore it is also proposed that the recording paper be heated at the time of erasing and that subsequently irradiation of the near infrared rays be carried out. In this case, both of the heating source for heating the recording paper and the near IR irradiation source become necessary. It goes without saying that the provision of both of the heating source and the near IR irradiation source leads to the result of an increase of production costs of the erasing apparatus.
SUMMARY OF THE INVENTION
Accordingly, a first object of the present invention is to provide an erasing technology for erasing the recording agent on a recording surface of a recording medium on which recording has been performed by a recording agent composed of a near IR erasable dye, with which the stabilization of the density of the recording agent on the recording medium for a long period is guaranteed to enhance the persistency of the recording medium and, at the same time, it becomes possible to substantially completely perform the erasing processing of the recording agent on the recording surface of the recording medium.
Also, a second object of the present invention is to provide an erasing technology for erasing the recording agent on a recording surface of a recording medium on which recording has been performed by a recording agent composed of a near IR erasable dye, in which it is not necessary to individually use both of the heating source and the near IR irradiation source at the time of erasing processing of the recording agent on the recording surface of a recording medium.
According to a first aspect by the present invention, it is assumed that the recording is carried out by a non-catalyst-containing recording agent composed of a near IR erasable dye for the recording medium, a liquid-state catalyst is coated there at the time of the erasing processing of the recording agent on the recording surface of recording medium, and subsequently the recording medium is heated and the near infrared rays are irradiated onto the liquid-state catalyst-coated surface of the recording medium.
Also, according to the second aspect by the present invention, it is assumed that the recording is carried out by a catalyst-containing recording agent composed of a near IR erasable dye for the recording medium, and the heating of the recording medium and the irradiation of the near infrared rays onto the recording surface of the recording medium are simultaneously carried out by the thermal emission and near IR irradiation source at the time of the erasing processing of the recording agent on the recording surface of recording medium.
According to the first aspect of the present invention, it is assumed that the recording is carried out on the recording medium by a non-catalyst-containing recording agent, and therefore the concentration of the recording agent of the recording surface can be stably maintained for a long period. Namely, the persistency of the recording medium for a long period can be guaranteed. On the other hand, the liquid-state catalyst is coated on the recording surface of the recording medium at the time of the erasing processing, and therefore the liquid-state catalyst is smoothly permeated through the whole recording agent, and therefore the recording agent on the recording surface of recording medium can be erased well by the heating and irradiation of near infrared rays.
Also, according to the second aspect of the present invention, the heating of the recording medium and the irradiation of the near infrared rays onto the recording surface of the recording medium are simultaneously carried out by the thermal emission and near IR irradiation source at the time of the erasing processing of the recording agent on the recording surface of recording medium, and therefore it is not necessary to individually provide the heating source and the near IR irradiation source.
REFERENCES:
patent: 4965591 (1990-10-01), Kurabayashi
patent: 5164287 (1992-11-01), Nagae et al.
patent: 5234799 (1993-08-01), Nagae et al.
patent: 5405726 (1995-04-01), Abe et al.
patent: 41 32 288 (1992-04-01), None
patent: 0 468 465 (1992-01-01), None
patent: 0 523 705 (1993-01-01), None
patent: 0 542 192 (1993-05-01), None
patent: 620123-A (1994-10-01), None
patent: 5-127571 (1993-05-01), None
patent: 6-59500 (1994-03-01), None
patent: 6-175537 (1994-06-01), None
Japan Office Action for Japanese Application No. 5-265253, which Attorney for Applicants is advised is dated Dec. 10, 1998.
Database WPI Week 9325, Derwent Publications Ltd., London, GB; AN 93-200676 & JP-A-5 125323 (MITA IND CO LTD), May 21, 1993.
European Search Report from EP 94302690, Aug./1994.
Haga Hirobumi
Kubota Masayuki
Sekioka Chiaki
Sugie Masaru
Uemura Hisashi
Fujitsu Limited
Markoff Alexander
Staas & Halsey , LLP
LandOfFree
Erasing method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Erasing method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Erasing method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2614381