JPH11990A - Ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid previously problems due to errors in paper selection, by detecting the information of paper selection, and determining the paper selection continuously until all printing is completed based on the detected results. SOLUTION: Paper is transported until a paper selection sensor 8 is situated out of a designated area, and thereafter paper selection is determined on the basis of detection signals of the sensor 8. If the paper has an obtained paper selection fitted to a designated printing mode, printing is carried out on the paper by reading out printing data from an output buffer 15, determination is made as to whether printing is completed or not for one paper. In the case where the paper selection does not fit to the printing mode, an alternation to the mode fitted to the paper is required to a host, and contents of the input and output buffers 14, 15 are made clear for requiring the re-sending of data. In this manner, printing in a state of the fed paper as not fitting to the printing mode can be avoided, thereby preventing the occurrence of failures of output.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus, and more particularly to an ink jet recording apparatus capable of matching a printing mode with a sheet.

[0002]

2. Description of the Related Art An ink jet recording apparatus has almost no vibration and noise during recording, and is particularly easy to colorize.
In addition to a printer that outputs data from a digital processing device such as a computer, it is also used for facsimile machines, copiers, and the like, but is particularly frequently used as a printer in a network environment.

[0003] The operation method of the printer under such a network environment is to connect a high-performance printer having a built-in network card, hard disk, printer sharing mechanism or the like directly to a network line, or to connect a personal computer as a printer server to the printer. There are two types of methods of preparing the data on a network and outputting from a printer locally connected to the personal computer.

[0004] The former operation method is often set and introduced when constructing a network, and is widely used because it is expensive and allows high-speed recording.
On the other hand, the latter operation method is a network that is realized by workstations and personal computers, and the necessary functions are carried out by the printer server, from high-performance color printers to low-cost inkjet recording. There is a wide range of choices for devices and thermal transfer printers, and in particular, color ink jet printers are being used.

[0005] Color ink jet printers are used in various ways such as colorizing reports, outputting photos and graphics samples, and outputting overhead projector (OHP) paper. Above all, presentations using OHP are used. OHP due to generalization
Recording on paper is important.

[0006] Ink-jet printers use liquid ink and land it on paper (recording medium) to perform recording. Therefore, the fixing of ink droplets on paper requires evaporation of moisture into the air and paper. This is done by infiltration.
If the evaporation of the water and the permeation of the ink are not carried out smoothly, the ink spreads on the paper surface and causes bleeding, so that a highly permeable ink is used.

However, most of OHP paper is a resin film, and several μm to several tens μm
Since only about ink receiving layer is applied,
The ink cannot penetrate sufficiently, and bleeding such as fusion of dots occurs. That is, as shown in FIG. 11, when the ink droplets I1 and I2 of different colors are sequentially landed on the OHP paper P, the ink droplets do not permeate the OHP paper P, so that the dots D1 and I2 formed by the ink droplets I1 and I2 of each color. D2
Are fused and the printing quality is significantly reduced.

Therefore, an ink jet printer has an OHP recording mode in addition to a normal printing mode, and various printings such as thinning out dots so as not to overlap each other and giving a time lag when printing adjacent dots. A printing method is adopted to enable printing on an OHP sheet.

In addition, in an ink jet printer, OH
Special recording mode for printing on special paper such as glossy paper, which has the same problem as P paper, back print film, textile for printing, etc. Some are equipped, and when printing on the wrong paper in such a special recording mode or printing on special paper in the normal recording mode, not only can not obtain a high-quality image, The recording result becomes unusable. In particular, when printing on an OHP sheet in the normal printing mode, not only does the dot bleed, but also the next paper feed is performed before the ink dries, and the already printed surface is rubbed and further stained. The back surface of the OHP sheet will be stained.

Also, since OHP paper is based on a resin film, misfeeds such as double feeding (a phenomenon in which a plurality of sheets are simultaneously fed) are liable to occur due to the paper being stuck together due to static electricity or moisture. This double feeding occurs not only between OHP sheets but also between OHP sheets and plain paper.

Therefore, when an OHP sheet is used in a conventional ink jet printer, the operator manually sets the OHP sheet one by one and feeds the sheet.

[0012]

However, when a printer is used in a network environment, there is not always an operator who uses the printer near the printer. Is difficult. For this reason, a plurality of OHP sheets must be set in the sheet cassette and automatic sheet feeding must be performed. However, since the operator cannot check the sheet one by one, even if a double feed occurs, the image may be printed as it is.

In this case, for example, if two sheets are shifted and double-fed, one page of data and two OHP sheets are wasted. In some cases, the necessary number of OHP sheets are set on plain paper and printing is performed. At this time, the required number of sheets is not sufficient due to the double feed, and printing is performed on the next plain paper, and printing must be performed again. . Further, there is a case where printing is performed on an unexpected sheet by switching the user.

Further, although the operator may start printing while keeping the printing mode in the normal printing mode despite printing on the OHP sheet, if the distance between the printer and the operator is large, Until the printing is completed, the user may not notice the failure of the printing.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an ink jet recording apparatus and a recording medium which can avoid a problem caused by an incorrect paper type in advance.

[0016]

According to a first aspect of the present invention, there is provided an ink jet recording apparatus for detecting information relating to a type of a fed sheet and feeding the sheet based on the detection result. The type of the paper is continuously determined from the start to the end of all the printing of the printing data.

According to a second aspect of the present invention, in the inkjet recording apparatus of the first aspect, the printing process is stopped when the type of the sheet obtained as a result of the determination does not match the designated printing mode. And

According to a third aspect of the present invention, in the inkjet recording apparatus of the second aspect, when the printing process is stopped, the printing data is cleared and information for requesting a change of the printing mode is output. And

According to a fourth aspect of the present invention, in the ink jet recording apparatus of the second aspect, when the printing process is stopped, information for requesting replacement of the paper is output.

According to a fifth aspect of the present invention, there is provided an ink jet recording apparatus according to any one of the first to fourth aspects, wherein a type of paper different from that at the start of printing before printing the printing data for one sheet. Is detected, the printing process is stopped, the paper being printed is discharged, and the printing data is cleared.

According to a sixth aspect of the present invention, there is provided the ink jet recording apparatus according to any one of the first to fifth aspects, wherein the type is not determined in a predetermined area of the sheet.

According to a seventh aspect of the present invention, in the ink jet recording apparatus according to any one of the first to sixth aspects, when the sheet is a sheet of a predetermined specific type, until there is permission after printing is completed. The next printing operation is not started.

An ink jet recording apparatus according to an eighth aspect of the present invention is the ink jet recording apparatus according to the seventh aspect, wherein permission is given when a predetermined time has elapsed after the end of printing.

According to a ninth aspect of the present invention, there is provided the ink jet recording apparatus according to the seventh or eighth aspect, wherein
The specific type of paper is a type of paper that requires a long time for ink drying.

According to a tenth aspect of the present invention, there is provided an ink jet recording apparatus comprising:
The ink jet recording apparatus according to claim 8 or 9, wherein the predetermined time is a time required until the ink dries to such an extent that the ink is not transferred when the specific type of paper is stacked.

[0026]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram of an ink jet recording apparatus according to the present invention. This ink jet recording apparatus records an image on a sheet 2 by a recording head 5 composed of an inkjet head while conveying a sheet 2 fed from a sheet cassette 1 by a sheet feed roller 3 and further conveying the sheet 2 by a conveying unit 4. Then, the paper is discharged to the paper discharge tray 6.

In this recording apparatus, a paper presence / absence sensor 7 for detecting the presence / absence of the paper 2 is disposed downstream of the paper supply roller 3, and information relating to the type of the paper 2 is provided downstream of the paper presence / absence sensor 7. A paper type sensor 8 as a detecting means for detecting the position is disposed. Here, the paper presence / absence sensor 7 uses a transmission type photo sensor, but the invention is not limited to this, and various other types of detection means such as an optical type or a mechanical type using a lever or the like can be used.

Although the transmission type photosensor is also used for the paper type sensor 8, the present invention is not limited to this, and an appropriate detection means may be used according to the type of paper to be determined. Further, the position of the paper type sensor 8 does not need to be on the downstream side of the paper feed roller 3, and may be on the upstream side of the paper presence sensor 7, the upstream side of the paper feed roller 3, or the recording head 5 is mounted. It can also be provided on a carriage.

Next, an outline of a control section of the ink jet recording apparatus will be described with reference to FIG. The control unit includes a microcomputer (hereinafter, referred to as a “CPU”) 10 for controlling the entire recording apparatus, a ROM 11 storing necessary fixed information, a RAM 12 used as a working memory and the like, , A parallel input / output (PIO) port 13 for transmitting and receiving various data and signals, an input buffer 14 for storing data (printing data) received from the host, and an output buffer for storing printing data to be output. 15 and parallel input / output (PIO) ports 16 and 17.

Here, the information transmitted / received between the host and the recording device indicates a printing mode, for example, an OHP sheet printing mode or a normal printing mode, which is transmitted from the host to the recording device. Information or paper type designation information for designating the type of paper to be used, and includes a data retransmission request, printing operation stop information, paper exchange instruction information, etc., which are sent from the recording device to the host.

The PIO port 16 has a driver 18 for driving the recording head 5 in accordance with the print data read from the output buffer 15 and a main scanning motor for moving a carriage on which the recording head 5 is mounted in the main scanning direction. 19
And a sub-scanning motor 20 for transporting the paper 2 in the sub-scanning direction
And a driver 21 for driving the. Also, PI
The O port 17 includes a paper presence sensor 7 and a paper type sensor 8.
, As well as various instruction signals from the operation panel 22. This operation panel 22
The user can also input printing mode and paper type information to be used.

Next, the operation of the ink jet recording apparatus will be described with reference to FIGS. First, an ordinary OHP sheet will be described with reference to FIG. 3. The OHP sheet is formed of a completely transparent or slightly cloudy transparent resin film for the purpose of use.
At first glance, which is the printing surface (the surface on which the receiving layer is formed)
Or it is very hard to understand. Therefore, a seal (or colored portion) C is provided as shown in FIG. 7A, or a cutout portion C is provided as shown in FIG. The direction is not wrong.

Here, if the OHP sheet shown in FIG. 1A is used, and a paper type sensor 8 is used as a paper type sensor, etc., the discrimination between the paper and the OHP sheet is performed based on the presence or absence of light transmission. Due to the seal S of the OHP sheet, the light transmittance is reduced, and there is a possibility that the OHP sheet is erroneously identified as paper. Therefore, when the use of such an OHP sheet is assumed, the detection signal of the paper type sensor 8 is invalidated in a certain area in advance (the discrimination is not performed in that area). Can be.

When an OHP sheet of this type is used, double feed can be detected by using a seal (or colored portion) S. That is, when a state corresponding to the seal (or colored portion) S is detected again in the area other than the first invalidated area until the printing of one page is completed, for example, as shown in FIG. It can be detected that the OHP sheets P1 and P2 are simultaneously conveyed (double feed) in a shifted state.

Further, by detecting the size of the seal S of the OHP sheet, it can be determined whether the sheet is being multi-fed or another sheet is inserted. In other words, until the printing of one page is completed, the seal (or colored portion) S is re-exposed to the area other than the area invalidated first.
When a state corresponding to is detected, if the size of the re-detected area is larger than the size of the seal (or colored portion) S attached to the OHP sheet, normal paper (plain paper) is supplied instead of the OHP sheet. It can be determined that the paper has been printed.

On the other hand, as shown in FIG.
In the case of indicating the orientation of the OHP sheet, it is not possible to respond by simple area determination, but a high-performance paper type sensor, for example, one that can detect the level of reflected light or transmitted light on the paper Can be dealt with. That is, since the OHP sheet also has a certain degree of opacity depending on the color of the veil film or the ink receiving layer, the surface treatment method, and the like, a clear density difference occurs between the single sheet and the multi-feeding. By detecting, it is possible to determine whether or not double feeding is performed. It is also possible to determine whether the sheet is an OHP sheet or paper. Further, the above-described area determination method can be used together.

Next, the recording medium according to the present invention will be described with reference to FIG.
This will be described with reference to FIG. The recording medium (paper) 25 stores information 26 indicating the type (type) of the paper in advance on a non-printing surface of a paper having a fixed non-printing surface such as glossy paper, back print film, and OHP sheet. It was printed.

Here, a bar code is used for the information 26, but a dot pattern, characters, or the like can also be used. The printing position is not limited to the upper right corner. In the case of opaque paper, there is no problem even if printing is performed on the entire non-printing surface. In the case of an OHP sheet, printing can be performed not only on the non-printing surface but also on the above-described seal (or colored portion). As described above, the information 26 is stored in the OHP sheet
, It is possible to detect at the paper feeding stage that the OHP sheet has slipped into plain paper. Further, by using a colorless and transparent recording material as a recording material for recording (printing) the information 26, it can be applied to an OHP sheet, ordinary paper (plain paper), and the like.

Further, as means for reading the information 26, means for detecting the density difference from the background color of the paper, and when the information 26 is recorded using magnetic ink, the magnetic head is used for the conductive ink. When the information 26 is recorded, the electrodes can be brought into contact with each other and read by an electric circuit.

The operation of the ink jet recording apparatus according to this embodiment will be described with reference to FIG.
FIG. 6 is a flowchart illustrating a first example of the printing process performed by the control unit. In this example, when the print data from the host side is received in the input buffer 14, the transfer of the received print data for one page to the output buffer 15 is started, and the paper feed sensor 7 detects the paper. It is determined whether or not paper is present (if paper is present). If paper is not present, a paper feeding operation is performed to feed paper. Then, if there is paper, it is determined whether or not a designated area determination release command for invalidating the determination of the paper type in a predetermined area of the paper has been given from the host side.

At this time, when the designated area judgment release command is given from the host side, the sheet is conveyed until the sheet type sensor 8 is positioned outside the designated area of the fed sheet. The type (type) of the fed sheet is determined based on the detection signal of (8). That is,
As described above, when special paper such as an OHP sheet, glossy paper, or back print paper is used, positioning of the paper,
By excluding parts such as seals indicating types from the judgment target,
It is possible to prevent the determination that the combination of the printing mode and the sheet is not correct every time.

Thereafter, it is determined whether or not the obtained paper type matches the designated printing mode. If the paper type matches the designated printing mode, the printing data is output from the output buffer 15. The printing is performed on the sheet, and it is determined whether the printing for one page is completed. Then, when the printing of the data for one page is completed, it is determined whether or not the printing data being received is present in the input buffer 14.
If there is data, it shifts to data transfer for the next one page.

On the other hand, if the obtained paper type does not match the designated printing mode, the printing operation is stopped, the data in the buffer is cleared, and the host side is switched to the printing mode. Request a change and request a retransmission of the imprint data. That is, in the first example, when the printing mode and the type of fed paper do not match, the fed paper is given priority and the host side is switched to the printing mode suitable for the paper. In order to obtain the print data corresponding to the sheet, the data in the buffer is cleared and the data retransmission is requested.

As described above, the information on the type of the fed paper is detected, and based on the detection result, continuous from the start of feeding of the paper to the end of all printing of the printing data. By judging the type of paper, it is possible to prevent imprinting while the supplied paper does not match the specified printing mode, thereby preventing defective output.

By giving priority to the paper type when the fed paper and the printing mode do not match, it is possible to prevent defective quality output.

FIG. 7 shows a second example of the printing process performed by the control unit.
It is a flowchart explaining an example. In this example, if the paper type obtained by the paper type determination in the first example does not match the designated printing mode, the printing operation is stopped and then the paper is discharged, and the host exchanges the paper. Request.
In other words, in the second example, when the printing mode and the type of the fed paper do not match, the designated printing mode is given priority and the host operator is adapted to the printing mode. At this time, since the data processed in the designated printing mode is transferred as the printing data, the data in the buffer is not cleared.

As described above, by giving priority to the printing mode when the fed paper and the designated printing mode do not match, retransmission of data becomes unnecessary, and the printing waiting time can be reduced.

FIG. 8 shows a third example of the printing process performed by the control unit.
It is a flowchart explaining an example. In this example, as in the above examples, data transfer for one page to the output buffer 15 is started, and it is determined whether or not there is paper. When the paper is fed and the paper is present, it is determined whether or not the host has issued a designated area determination release command for invalidating the determination of the paper type in a predetermined area of the paper.

At this time, when the designated area judgment release command is given from the host side, the sheet is transported until the sheet type sensor 8 is positioned outside the designated area of the fed sheet, and then the sheet type sensor The type (type) of the fed sheet is determined based on the detection signal of (8). Thereafter, it is determined whether or not the obtained paper type matches the designated printing mode, and if the paper is suitable for the designated printing mode, the printing data is read from the output buffer 15 and the paper is read. And determines whether or not printing for one page has been completed.

At this time, if the printing of one page has not been completed, the process returns to the determination process of whether or not there is paper, and returns to step S1.
When the printing of the page is completed, it is determined whether or not there is the received printing data in the input buffer 14, and if there is the data, the process proceeds to the data transfer of the next one page.

On the other hand, if the obtained paper type does not match the designated printing mode, the printing operation is stopped, then the paper is discharged, the data in the buffer is cleared, and the host Requests retransmission of the print data. That is, in the third example, the sheet type is detected and determined from the start of feeding of one page of paper to the end of printing of the one page of data, and the printing mode is set. If the paper type does not match the printing mode, a paper ejection, data clear, and data retransmission request are performed.

Thus, when a different type of paper is detected during the actual printing on the paper, for example, the required number of types of paper are printed on a place where another type of paper is set. If sheets that have already been set due to double feeding or miscounting are fed, but have been set in a stack, parts such as OHP sheets that have a seal or the like for the purpose of positioning the paper type and paper feed position may be attached. If multiple feeds are detected in parts that should not exist, or if the number of times detected within one page, printing can be stopped immediately to remove the defective prints, and the cumulative number of defective prints Can be prevented.

FIG. 9 shows a fourth example of the printing process performed by the control unit.
It is a flowchart explaining an example. In this example, at the start of printing, data transfer is performed to perform a paper feeding operation, it is determined whether or not a designated area determination release command has been received from the host, and a designated area determination release command has been received. , The determination release flag is turned on. When the designated area determination release command is not received, the paper type sensor 8
After determining the paper type based on the detection signal, it is determined whether or not print information on the paper is detected, and when the print information on the paper is detected, the determination release flag is set to the ON state.

Thereafter, it is determined whether or not the paper type and the printing mode match. If the paper type and the printing mode match, a printing operation is performed, and the data for one page is completed. Then, if the data for one page has not been completed, the untransferred data is transferred using the data for one page. In this case, in the next paper feed process, the output signal of the paper feed sensor is checked, and if paper is present,
The process does not perform the sheet feeding operation again.

When the printing of the data for one page is completed, the determination release flag is turned off, and then the transfer to the next page data is started.

On the other hand, if the paper type and the printing mode do not match, it is determined whether or not the determination release flag is ON. After the paper processing, the data in the buffer is cleared, a request for retransmission of the data is made to the host side, and the processing shifts to the printing start processing. When the determination release flag is OFF, it is determined that the sheet is erroneous, and a warning and a printing mode or paper replacement is requested to the host without clearing the data in the buffer.

Next, the sequence after the end of printing will be described with reference to FIG. When recording on some special paper such as an OHP sheet or glossy film in the paper, if there is not enough time for the ink to dry as described above, The printing surface may be rubbed by the performed paper to bleed the ink, or the back side of the stacked paper may be stained. Therefore, in the sequence after the end of printing, until the next recording permission is given, or
The next recording is not started until a certain time has elapsed.

That is, after the printing (printing) is completed, the control unit determines whether or not the paper type is a predetermined type of paper, such as an OHP sheet or a glossy film, which needs to wait for a certain period of time. Is determined. Then, after setting a certain standby time according to the type of the paper and starting a timer, it is determined whether or not the printer opening permission is given, and when the printer opening permission is given, the printer is opened, If the printer release permission is not given, it is determined whether or not the timer has expired and it is determined whether or not the standby time has elapsed. When the standby time has elapsed, the printer is opened.

Therefore, when printing is performed on a sheet such as an OHP sheet or a glossy film which needs to wait for a certain period of time, the next recording is not started until the operator permits the printer to be opened. This prevents the OHP sheet or the like recorded by the printing request from another operator from being spoiled until the operator who performed the recording removes the output sheet.
Even when there is no permission to open the printer, when the time required for the ink to dry elapses, it can be considered that the permission to open the printer has been granted, so that the next print request can be accepted and the next print request can be accepted forever. A situation in which the operator cannot perform printing can be avoided.

[0060]

As described above, according to the ink jet recording apparatus of the first aspect, the information on the type of the fed paper is detected, and all the printing of the printing data is completed from the start of the feeding. The paper type is continuously determined until the printing is started, so that printing on paper that does not conform to the printing mode before printing starts can be avoided, or paper that does not conform to the printing mode during printing can be avoided. For example, it is possible to prevent imprinting on the image, and it is possible to reduce the output of imprinting failure.

According to the ink jet recording apparatus of claim 2, in the ink jet recording apparatus of claim 1,
When the type of paper obtained as a result of the determination does not match the specified printing mode, the printing process is stopped, so that the expected quality, such as the combination of high-quality recording mode and plain paper, Unavailable combinations and high-speed recording modes and OH
It is possible to reduce the possibility that printing is performed with a combination having remarkable quality deterioration, such as a combination with P paper.

According to the ink jet recording apparatus of claim 3, in the ink jet recording apparatus of claim 2,
When the printing process is stopped, the printing data is cleared and the information requesting the change of the printing mode is output, so that the printing can be performed in the printing mode suitable for the paper to be used. The output of poor photographing can be reduced.

According to the ink jet recording apparatus of claim 4, in the ink jet recording apparatus of claim 2,
Since the information requesting the exchange of the paper is output when the printing process is stopped, the printing can be performed on the paper suitable for the printing mode, and the output of printing failure can be reduced. In addition, the printing time throughput can be reduced.

According to a fifth aspect of the present invention, in the ink jet recording apparatus according to any one of the first to fourth aspects, before printing the printing data for one sheet, the type different from that at the start of printing. When the sheet is detected, the printing process is stopped, the sheet being printed is discharged, and the printing data is cleared. Therefore, if different types of sheets are mixed during printing, this is removed. Therefore, accumulation of defective printing can be reduced.

According to the ink jet recording apparatus of the sixth aspect, in the ink jet recording apparatus of any one of the first to fifth aspects, the type is not determined in a predetermined area of the sheet. Erroneous determination of mismatch between the print mode and the printing mode can be prevented.

According to the ink jet recording apparatus of claim 7, in the ink jet recording apparatus of any one of claims 1 to 6, when the sheet is a sheet of a predetermined specific type, permission is given after the end of printing. Since the next printing operation is not started until then, it is possible to prevent the recording surface and the next paper from being stained when printing on paper that requires a long time for ink drying.

According to the ink jet recording apparatus of claim 8, in the ink jet recording apparatus of claim 7,
The configuration is such that the permission is granted when a certain period of time has elapsed after the end of printing, so that it is possible to avoid a situation where the recording apparatus is in a standby state forever.

According to the ink jet recording apparatus of the ninth aspect, in the ink jet recording apparatus of the seventh or eighth aspect, the specific type of paper is a type of paper that takes a long time to dry the ink. It is possible to prevent a situation where the next recording is performed while the recording is dry.

According to the ink jet recording apparatus of the tenth aspect, in the ink jet recording apparatus of the eighth or ninth aspect, the ink is dried to such an extent that the ink is not transferred when a specific type of paper is overlaid for a certain period of time. , It is possible to prevent a situation where the next recording is performed while the ink is not dried, and to avoid a situation where the standby state is unnecessarily continued.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an ink jet recording apparatus according to the present invention.

FIG. 2 is a block diagram of a control unit of the recording apparatus.

FIG. 3 is an explanatory diagram illustrating an example of a general OHP sheet.

FIG. 4 is an explanatory diagram for explaining multi-feeding;

FIG. 5 is an explanatory diagram for explaining a sheet.

FIG. 6 is a flowchart illustrating a first example of a printing process performed by a control unit.

FIG. 7 is a flowchart illustrating a second example of the printing process performed by the control unit.

FIG. 8 is a flowchart illustrating a third example of the printing process performed by the control unit.

FIG. 9 is a flowchart illustrating a fourth example of the printing process performed by the control unit.

FIG. 10 is a flowchart for explaining the sequence after the end of printing performed by the control unit.

FIG. 11 is an explanatory diagram illustrating printing on OHP paper.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... paper feed part, 2 ... paper, 3 ... paper feed roller, 4 ... transport part,
5: recording head, 6: paper discharge tray, 7: paper feed sensor, 8
... Paper type sensor.

Claims (10)

[Claims] 1. An ink jet recording apparatus which performs recording by ejecting ink droplets onto a sheet, detects information relating to the type of the fed sheet, and prints data from the start of feeding of the sheet based on the detection result. An ink jet recording apparatus for continuously determining the type of the paper until all the printing is completed. 2. The ink jet recording apparatus according to claim 1, wherein the printing process is stopped when the type of the sheet obtained as a result of the determination does not match the specified printing mode. apparatus. 3. The ink jet recording apparatus according to claim 2, wherein when the printing process is stopped, the printing data is cleared and information requesting a change of the printing mode is output. apparatus. 4. The ink jet recording apparatus according to claim 2, wherein when the printing process is stopped, information requesting replacement of the paper is output. 5. An ink jet recording apparatus according to claim 1, wherein a print of a type different from the start of printing is detected before printing the print data of one sheet. An ink jet recording apparatus which stops processing, discharges a printing sheet, and clears printing data. 6. The ink jet recording apparatus according to claim 1, wherein the type is not determined in a predetermined area of the sheet. 7. The ink jet recording apparatus according to claim 1, wherein when the sheet is a predetermined type of sheet, the next printing operation is performed until permission is given after the end of printing. An inkjet recording apparatus characterized by not starting. 8. An ink jet recording apparatus according to claim 7, wherein permission is given when a predetermined time has elapsed after the end of printing. 9. The ink jet recording apparatus according to claim 7, wherein the specific type of paper is a type of paper that takes a long time to dry ink. 10. The ink jet recording apparatus according to claim 8, wherein the predetermined time is a time required for the ink to dry so that the ink is not transferred when the specific type of paper is stacked. An ink jet recording apparatus characterized by the above-mentioned.