JP7119614B2 - Image forming device, ink - Google Patents

Description

The present invention relates to an image forming apparatus and ink .

A water-based ink containing water is known as an ink used in an inkjet recording method. When such a water-based ink is applied to a recording medium such as continuous paper continuous in the conveying direction using an inkjet recording apparatus capable of printing at high speed, the water-based ink applied to the recording medium is formed. It is necessary to dry the image area in a short time. Contact heating means such as heating rollers are known as drying means.

Patent Literature 1 discloses a heating roller, in which a long belt-shaped base material to which a liquid material is applied is wound around the outer peripheral surface and rotated while being heated to convey the base material along a conveying path on the outer peripheral surface; A drying apparatus is disclosed that has a plurality of transport rollers that are provided in the vicinity of the outer peripheral surface of the heating roller and that transport the substrate.

However, there is a problem that a large number of heating members are required in order to sufficiently dry the regions to which the liquid is applied and which are formed on the member being conveyed. In addition, even if the transported member is sufficiently dried, if a member is provided that contacts the region to which the liquid is applied, there is a problem that part of the region to which the liquid is applied is peeled off (white spots). be.

According to a first aspect of the present invention , there is provided an image forming apparatus comprising: ink; ink containing means for containing the ink; ink applying means for applying the ink to a continuous form; The device is a drying device for drying the continuous paper, and includes a plurality of heating members arranged side by side in the conveying direction of the continuous paper for contacting the continuous paper and heating the continuous paper; a transport path along which the continuous form is transported while being in contact with the plurality of heating members; a second path along which the continuous paper is transported while contacting the at least one heating member that contacted the first path again; and when the continuous paper is transported along the second path. and a contact guide member for guiding the continuous paper into contact with the heating member, the contact guide member contacting the inked area of the continuous paper and receiving the ink. The region is a drying device having a temperature of 60° C. or more and 120° C. or less when contacting the contact guide member, and the ink has a Martens hardness of , 30 N/mm ² or more .
[How to make]
The ink is coated on a glass plate, and the coated ink is dried under reduced pressure at 100° C. for 3 hours to obtain a dry film with an average thickness of 5 μm.

The drying apparatus of the present invention can efficiently dry the region to which the liquid is applied and which is formed on the member to be transported by the heating member, and suppresses white spots in which part of the region to which the liquid is applied is peeled off. effect that can be achieved.

1 is a schematic explanatory diagram of an image forming apparatus according to a first embodiment; FIG. It is an expansion explanatory drawing of the drying apparatus in 1st Embodiment. FIG. 4 is an explanatory diagram for explaining a state of contact with a heating roller; It is an expansion explanatory drawing of the drying apparatus in 2nd Embodiment. It is an expansion explanatory drawing of the drying apparatus in 3rd Embodiment. FIG. 5 is an explanatory diagram for explaining the contact distance and winding angle to the heating roller and the heating drum; 4 is a table showing an example of the relationship between the roller diameter of a heating roller and the cockling of continuous paper. It is an expansion explanatory drawing of the drying apparatus in 4th Embodiment. FIG. 11 is an enlarged explanatory view of a main part of a drying device according to a fifth embodiment; FIG. 11 is an enlarged explanatory view of a main part of a drying device according to a sixth embodiment; FIG. 11 is a schematic explanatory diagram of an image forming apparatus according to a seventh embodiment;

A drying apparatus according to the present invention will be described below. In addition, the present invention is not limited to the embodiments shown below, and can be changed within the scope of those skilled in the art, such as other embodiments, additions, modifications, deletions, etc. is also included in the scope of the present invention as long as the functions and effects of the present invention are exhibited.

<<Drying device>>
The present invention relates to a drying apparatus for drying a member to which a liquid is applied and to be conveyed, wherein the drying device heats the member to be conveyed by coming into contact with the member to be conveyed, and is arranged in the conveying direction of the member to be conveyed. a plurality of heating members arranged; and a conveying path along which the conveyed member is conveyed while being in contact with the plurality of heating members. a first route through which the member is conveyed while being in contact with a heating member; and a second route through which the conveyed member is conveyed while being brought into contact again with at least one of the heating members with which the member was conveyed on the first route; Martens hardness at 120° C. of a dry film prepared from the liquid by the following preparation method is 30 N/mm ² or more.
[How to make]
The liquid is coated on a glass plate and dried under reduced pressure at 100° C. for 3 hours to obtain a dry film with an average thickness of 5 μm.
Hereinafter, the drying apparatus of the present invention will be described together with an image forming apparatus having the drying apparatus.

First, an image forming apparatus according to a first embodiment of the invention will be described with reference to FIG. FIG. 1 is a schematic explanatory diagram of an image forming apparatus according to the first embodiment.

This image forming apparatus is an inkjet recording apparatus, and is an example of a liquid application unit that ejects and applies ink, which is liquid of a desired color contained in a liquid container, onto continuous paper 110, which is a member to be conveyed. has a liquid applying unit 101 including a liquid ejection head. Note that the liquid storage container is an example of liquid storage means, and examples thereof include an ink cartridge, an ink bottle, and the like.

In the liquid applying unit 101, for example, full-line heads 111A, 111B, 111C, and 111D for four colors are arranged from the upstream side in the conveying direction of the continuous paper 110. As shown in FIG. Each head 111 applies black K, cyan C, magenta M, and yellow Y liquids to the continuous paper 110, respectively. Note that the types and number of colors are not limited to this.

Note that the liquid applying unit 101 may be either a serial type in which the ejection head is moved or a line type in which the ejection head is not moved. Also, the liquid applying unit 101 employs an inkjet recording method, but may employ another method. Examples thereof include blade coating, gravure coating, bar coating, roll coating, dip coating, curtain coating, slide coating, die coating, and spray coating.

The continuous paper 110 is unwound from the main winding roller 102 , fed by the transport roller 112 of the transport unit 103 onto a transport guide member 113 arranged facing the liquid applying unit 101 , and guided by the transport guide member 113 . transported by

The continuous paper 110 to which the liquid has been applied by the liquid applying unit 101 passes through the drying device 104 according to the present invention, is sent by the discharge roller 114 , and is taken up by the take-up roller 105 .

Next, the drying apparatus according to the first embodiment will be described with reference to FIGS. 2 and 3 as well. FIG. 2 is an enlarged explanatory view of the drying device in the first embodiment, and FIG. 3 is an explanatory view for explaining the contact portion of the continuous paper with the heating roller.

The drying device 104 includes contact heating means 10 that heats the continuous paper 110 by contacting the surface of the continuous paper 110 opposite to the surface to which the liquid is applied. Guide rollers 17A and 17B for guiding the continuous paper 110 that has passed through the contact heating means 10 are also provided.

The contact heating means 10 includes heating rollers 11A to 11E, which are examples of a plurality of heating members each having a curved contact surface 11a, which is a peripheral surface that contacts the continuous paper 110. As shown in FIG. The contact heating means 10 also includes contact guide rollers 13A to 13D, which are examples of contact guide members for guiding the continuous paper 110 to come into contact with the contact surfaces 11a of the heating rollers 11D to 11A.

Here, a plurality of heating rollers 11A to 11E (hereinafter referred to as "heating rollers 11" when not distinguished; the same applies to other members) are arranged side by side in a curved shape. The contact guide roller 13 is arranged between the adjacent heating rollers 11, and the liquid-applied area on the continuous paper 110 (hereinafter referred to as an "image portion" which is an example of the "liquid-applied area"). explain). It should be noted that the term "area to which the liquid is applied" refers to the area of the surface of the conveyed member to which the liquid is applied, and does not include the area of the surface to which the liquid is not applied.

It should be noted that the contact guide roller 13 is preferably a roller having a fine uneven structure on its surface. The roller having a fine uneven structure includes, for example, a roller having substantially spherical bodies fixed to its surface, a roller coated with a film, tape, etc. having substantially spherical bodies fixed to its surface. It is preferable that the fixed substantially spherical bodies are embedded in a roller, a film, a tape, or the like, and partially exposed from the surface to form an uneven structure. The diameter of the substantially spherical body is preferably 20 μm or more and 200 μm or less. Examples of the material forming the substantially spherical body include glass and ceramics. By using the contact guide roller 13 having a fine uneven structure on the surface, the adhesive force generated between the image portion and the surface of the contact guide roller 13 causes white spots in the image portion to be partly peeled off, and components of the peeled image portion to be contact-guided. It is possible to suppress member contamination that is transferred and formed on the roller 13 .

Further, the temperature of the image portion when the contact guide roller 13 and the image portion on the continuous form 110 contact each other is preferably 60° C. or more and 120° C. or less. When the temperature of the image area is 60° C. or higher, the image area can be dried at the same time as the transportation, so that white spots and member contamination caused by insufficient drying of the image area can be suppressed. When the temperature of the image portion is 120° C. or less, the image portion can be brought into contact with the contact guide roller 13 in a state in which the image portion is not thermally melted, so white spots and member contamination can be suppressed.

The drying device 104 has a conveying path (conveying path, conveying path) 20 for the continuous paper 110 which is composed of the plurality of heating rollers 11 and contact guide rollers 13 .

This transport path 20 is a first path (hereinafter referred to as "first path Y1") in which continuous paper 110 is transported in a first direction (Y1 direction) while being in contact with a plurality of heating rollers 11A to 11E. , and a second route (hereinafter referred to as “second route Y2”) in which the sheet is transported in the second direction (Y2 direction) while contacting again the plurality of heating rollers 11D to 11A that were in contact with the first route. there is

In this embodiment, the continuous form 110 forms a path that contacts two or more heating rollers 11 (first heating members) when conveyed along the second path Y2. It may be a path that contacts the (first heating member). In other words, when the continuous form 110 is conveyed along the second path Y2, it does not need to contact all of the heating rollers 11A to 11E again.

Here, the continuous paper 110 is conveyed on the first path Y1 while the outside (the side receiving the tension) of the plurality of heating rollers 11A to 11E arranged in a curved shape is in contact with the heating rollers 11A to 11E. . After that, the continuous form 110 changes its direction on the second path Y2, and is guided inside the plurality of heating rollers 11E to 11A (on the loose side) by the contact guide roller 13 to the heating rollers 11D to 11A. Conveyed while touching.

At this time, as shown in FIG. 3, the continuous paper 110 is conveyed through the first path Y1 and the second path Y2 while simultaneously contacting two portions (parts a and b) of the heating roller 11 which are separated from each other. It will be.

In this manner, the members conveyed at the same time are brought into contact with two different locations of the same heating member (heating roller) to be heated.

As a result, it is possible to efficiently dry the conveyed member with a small number of heating members.

Next, a second embodiment of the invention will be described with reference to FIG. FIG. 4 is an enlarged explanatory view of the drying device in the second embodiment.

In this embodiment, the configuration of the image forming apparatus other than the drying device 104 is the same as that of the first embodiment.

Further, the drying device 104 has a portion where a plurality of (here, two) heating rollers 11 are arranged between the contact guide rollers 13, 13 in the drying device 104 of the first embodiment.

Even with such a configuration, depending on the arrangement positions of the heating roller 11 and the contact guide roller 13, the sheet can be guided so as to be in contact with the heating roller 11 even when conveyed in the second direction Y2.

By arranging the contact guide roller 13 of the present embodiment, the portion of the continuous form 110 conveyed on the first route Y1 and the second route between the heating rollers 11, 11 where the contact guide roller 13 is not arranged. A space 120 is formed between the portions of the continuous paper 110 being transported on Y2.

Therefore, in this space 120, for example, a sensor unit for controlling the temperature of the heating roller 11 and a temperature control unit 121 for controlling the temperature can be arranged.

Next, a third embodiment of the invention will be described with reference to FIG. FIG. 5 is an enlarged explanatory view of the drying device in the third embodiment.

In this embodiment, the configuration of the image forming apparatus other than the drying device 104 is the same as that of the first embodiment.

The drying device 104 is located downstream of the plurality of heating rollers 11 on the first path Y1 and upstream of the plurality of heating rollers 11 on the second path Y2. 12 are placed. The heating drum 12 has a curved contact surface (peripheral surface) with a smaller curvature than the contact surface of the heating roller 11 .

Here, the heating drum 12 is rotationally driven, and the heating roller 11 rotates together with the fed continuous paper 110 .

The heating roller 11E, the heating drum 12, and the guide roller 17 form a path (conveyance path) for winding the continuous paper 110 around 70% or more, preferably 80% or more of the circumference of the heating drum 12. there is These heating drums 12 and guide rollers 17 change the conveying direction of the continuous form 110 from the direction of the first path Y1 to the direction of the second path Y2.

At this time, the contact distance of the continuous paper 110 with respect to the heating drum 12 is longer than the contact distance of the continuous paper 110 with respect to the heating roller 11 . The “contact distance” is the distance that the continuous paper 110 is in contact with the circumferential surface of the heating drum 12 and the heating roller 11 in the circumferential direction (conveyance direction). When the heating member is a curved surface member having a curved surface as a contact surface, it is the distance of contact with the curved surface in the direction (conveyance direction) along the circumferential direction of the curved surface.

Here, the contact distance and winding angle will be described with reference to FIG. FIG. 6 is an explanatory diagram of the contact distance and winding angle with respect to the heating roller and the heating drum.

As shown in FIG. 6, the contact distance L2 between the contact surface 12a, which is the peripheral surface of the heating drum 12, and the continuous paper 110 is the contact distance between the contact surface 11a, which is the peripheral surface of the heating roller 11, and the continuous paper 110. The conveying path is configured to be longer than L1.

Here, the winding angle .theta.2 of the continuous paper 110 with respect to the contact surface 12a of the heating drum 12 is set larger than the winding angle .theta.1 of the continuous paper 110 with respect to the contact surface 11a of the heating roller 11 (.theta.2>.theta.1).

As shown in FIG. 6, the winding angles θ2 and θ1 (collectively referred to as “winding angles θ”) are set at a point Ps where the continuous paper 110 starts contacting the contact surfaces 12a and 11a and ends the contact. It means the angle that the point Pe forms with the center O.

Therefore, when the winding angle θ increases, the contact distance increases if the diameter of the rotating body is the same, and even if the winding angle θ is the same, the contact distance increases as the diameter of the rotating body increases.

In this embodiment, the diameter of the heating drum 12 is larger than that of the heating roller 11 and the winding angle θ2 is larger than θ1. is longer than the contact distance L1 between the contact surface 11 a of the heating roller 11 and the continuous form 110 .

As described above, even if the winding angle θ is the same, the larger the diameter of the rotor, the longer the contact distance. Therefore, even if the heating drum 12 and the heating roller 11 have the same diameter and the winding angle θ2 is set larger than θ1, the contact distance L2 between the contact surface 12a of the heating drum 12 and the continuous paper 110 is equal to the contact distance of the heating roller 11. It is longer than the contact distance L1 between the surface 11a and the continuous form 110. - 特許庁

As a result, the heating drum 12 applies a large amount of heat to the continuous paper 110 that has been conveyed along the first path Y1 and heated by the heating roller 11, so that the continuous paper 110 can be heated and dried.

In this case, the continuous paper 110 immediately after the application of the liquid is transported along the first path Y1 while being in contact with the heating roller 11, thereby reducing cockling. It adheres closely to the peripheral surface of the heating drum 12 and can be dried efficiently.

In other words, since the strength of the continuous paper 110 is low in a state in which time has not passed since the application of the liquid, the back side of the continuous paper 110 is covered over a wide range (long contact distance) around the rotating body. It is difficult to adhere to the surface (contact surface).

Therefore, in the initial state where the applied liquid has not yet dried, the winding angle of the continuous paper 110 around the heating roller 11 is reduced to shorten the contact distance.

Here, by increasing the curvature of the heating roller 11, the tension generated when the continuous paper 110 is conveyed changes into the pressing force at the contact portion with the heating roller 11, so that the contact state with the heating roller 11 becomes uniform. Become. In this state, cockling and wrinkling of the continuous paper 110 are suppressed or corrected. be able to do it.

In this way, the continuous paper 110 in which cockling is suppressed and the drying progresses can be brought into close contact with the contact surface of the rotating body (curved surface) even if the contact distance is increased.

Therefore, by increasing the contact distance of the continuous paper 110 with the heating drum 12 arranged on the downstream side of the plurality of heating rollers 11, a large amount of heat is supplied to the continuous paper 110, and drying is performed efficiently in a short time. can be done.
Note that the large-diameter heating member such as the heating drum 12 has a large contact area with the member to which the liquid is applied and conveyed, so that the dryness can be improved, but the area to which the liquid is applied is larger. heated. Therefore, for example, when the area to which the liquid is applied and the contact guide member come into contact with each other, image peeling ("white spots" to be described later) is likely to occur. It is more preferable to satisfy the range of

Furthermore, in this embodiment, the back surface of the continuous paper 110 is brought into contact with the heating roller 11 again on the downstream side of the heating drum 12 .

As a result, for example, the heat transfer of the heating roller 11 and the heat transfer of the heating drum 12 in the first path Y1 evaporate the water content of the ink, and then the heat transfer of the heating roller 11 in the second path Y2 evaporates the ink. The solvent can evaporate and the ink can be fixed to the paper, which is the continuous paper 110 .

Next, an example of the relationship between the roller diameter of the heating roller 11 and the cockling of the continuous paper 110 will be described with reference to FIG. FIG. 7 is a table showing an example of the relationship between the roller diameter of the heating roller and the cockling of continuous paper.

FIG. 7 shows the results of measuring the cockling height and cockling pitch occurring in the continuous paper 110 while changing the diameter of the heating roller 11 and visually confirming the presence or absence of visible cockling.

From this result, in this example, by setting the diameter of the heating roller 11 to 200 mm, the height of the cockling is almost halved compared to when the diameter of the heating roller 11 is 250 mm. , you can see that the cock ring is gone.

Therefore, the diameter of the heating roller 11 is preferably 200 mm or less, more preferably 100 mm or less.

Next, a fourth embodiment of the invention will be described with reference to FIG. FIG. 8 is an enlarged explanatory view of the drying device in the fourth embodiment.

In this embodiment, the configuration of the image forming apparatus other than the drying device 104 is the same as that of the first embodiment.

The drying device 104 includes ten heating rollers 11 (11A to 11J), the heating drum 12, and the heating rollers 11 (11A to 11J) that constitute the contact heating means 10. The contact guide guides the continuous paper 110 to come into contact with the heating rollers 11 (11A to 11J). It has rollers 13 (13A to 13J).

Further, guide rollers 17A to 17D for guiding the continuous paper 110 to the contact heating means 10 and a guide roller 17E for winding the continuous paper 110 around the heating drum 12 are provided. Furthermore, heating rollers 14A and 14B also serving as guide rollers for guiding the continuous form 110 coming out of the contact heating means 10 are provided.

The contact heating means 10 has ten heating rollers 11 (11A to 11J) arranged in an arc shape around a heating drum 12. As shown in FIG. Here, the distances from the center of the heating drum 12 to the centers of the heating rollers 11 are the same, but the center of the heating drum 12 coincides with the center of the arc of the heating rollers 11 arranged in an arc. do not have to.

As a result, when the continuous form 110 is transported in contact with the plurality of heating rollers 11, no load is applied to the continuous form 110, and the continuous form 110 can be transported with proper tension.

Then, the continuous paper 110 guided to the contact heating means 10 by the guide roller 17D is in contact with the outer side (opposite side to the heating drum 12) of the plurality of heating rollers 11A to 11J arranged in an arc shape, and is moved through the first path. Y1 is transported.

After that, the continuous paper 110 reaches the peripheral surface of the heating drum 12, is wound around the entire circumference of the heating drum 12, and is brought into contact therewith. be guided to Then, the continuous paper 110 is conveyed along the second path Y2 while being guided by the contact guide rollers 13A to 13J to the inside of the heating rollers 11J to 11A (on the side of the heating drum 12).

As a result, even if the number of heating members is increased, the size of the device can be reduced. The drying speed can be increased by increasing the number of heating members.

Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 9 is an enlarged explanatory view of a main part of a drying device according to the fifth embodiment.

In the present embodiment, the contact guide roller 13 arranged between the adjacent heating rollers 11 and 11 has a first position shown in FIG. It is arranged so as to be movable in the direction of the arrow between a second position shown in FIG. Thereby, the contact guide roller 13 can change its position with respect to the conveying path outside the group of the heating rollers 11 .

The movement of the contact guide roller 13 can be performed manually, for example, by manipulating a handle, or can be performed by an actuator provided with a drive source.

With this configuration, in order to improve workability when the continuous form 110 is initially loaded, the contact guide roller 13 is moved by a predetermined distance N1 from the conveying path outside the group of the heating rollers 11 during the loading operation. A retracted position can be set apart.

After the continuous paper 110 is loaded, the contact guide roller 13 is moved to a pressing position where it is a predetermined distance N2 (N2<N1) with respect to the conveying path outside the group of the heating rollers 11, and the continuous paper 110 is moved. The adjacent heating rollers 11, 11 are pressed inward from the common outer tangent line. As a result, the contact area of the continuous paper 110 with respect to the heating roller 11 can be increased.

On the other hand, when the contact guide roller 13 presses the continuous form 110 as described above, the contact guide roller 13 presses the image portion formed on the continuous form 110 while directly contacting it. Become. Therefore, by forming the image portion using a liquid having Martens hardness, which will be described later, white spots and member stains can be suppressed.

Next, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 10 is an enlarged explanatory view of a main part of the drying device in the sixth embodiment.

In this embodiment, the first heating rollers 11A to 11K and the contact guide rollers 13A to 13H are arranged side by side.

Between the group of the first heating rollers 11A to 11E and the group of the first heating rollers 11G to 11K, which are arranged in a curved shape, there are interposed paths in which the heating rollers 11E, 11F, and 11G are linearly arranged. By doing so, a portion of the conveying path is bent to include a straight path portion in the curved path.

In other words, the shape of the conveying path (conveying path) is not limited to a curved shape, and may include a linear shape (straight path) (this embodiment).

In the above-described embodiment, an example is described in which the plurality of first heating members and second heating members are rotating bodies, but some or all of them may be non-rotating bodies.

Further, in each of the above-described embodiments, an example in which the conveying path is an arcuate, arcuate, or curved path has been described, but the present invention is not limited to this. For example, a path that bends in the middle of the Y1 direction (or the Y2 direction), a crank-shaped path, or the like can be used.

Further, in each of the above-described embodiments, a simple roller (rotating body) other than the heating member may be arranged in the middle of the configuration in which the plurality of first heating members are continuously arranged.

In addition to recording images such as letters and figures with liquid such as ink, images with no meaning such as patterns can be printed on members conveyed by the image forming apparatus for the purpose of decoration. It may be applied with a liquid such as ink.

Further, in each of the above-described embodiments, an example in which the second direction is opposite to the first direction has been described. However, the second direction is not limited to the opposite direction. good.

Next, an image forming apparatus according to a seventh embodiment of the invention will be described with reference to FIG. FIG. 11 is a schematic explanatory diagram of an image forming apparatus according to the seventh embodiment.

This image forming apparatus has a first printing unit 1001 that prints on one side of a continuous form 110 and dries it between a main winding roller 102 and a winding roller 105, and a first printing unit 1001 that prints on one side. A reversing unit 1003 for reversing the front and back of the continuous paper 110 and a second printing unit 1002 for printing on the other side of the continuous paper 110 and drying are arranged.

The configurations of the liquid applying unit 101, the conveying unit 103, and the drying device 104 of the first printing unit 1001 and the second printing unit 1002 are substantially the same (or may be the same) as in the first embodiment. It can be the same as or substantially the same as the sixth embodiment.

Here, the liquid applying section 101 of the first printing unit 1001 serves as first liquid applying means for applying liquid to the first surface of the continuous paper 110, which is a member to be conveyed. The liquid applying section 101 of the second printing unit 1002 serves as a second liquid applying means for applying liquid to the second surface opposite to the first surface of the continuous paper 110 which is the conveyed member.

Also, the drying device 104 of the first printing unit 1001 serves as the first drying device in which the first surface of the continuous paper 110 contacts the heating roller 11 in the first path Y1. The drying device 104 of the second printing unit 1002 serves as a second drying device in which the second surface of the continuous paper 110 contacts the heating roller 11 in the first path Y1.

Here, in the drying device 104 of the first printing unit 1001, since the image portion is formed only on the first side of the continuous paper 110, the contact guide roller 13 corresponds to the member that comes into direct contact with the image portion. . On the other hand, in the drying device 104 of the second printing unit 1002, since the image portions are formed on both the first surface and the second surface of the continuous paper 110, the contact guide rollers are the members that come into contact with the image portions. In addition to 13, the heating roller 11 also applies. In other words, since the chances of white spots and member stains occurring increase, the need to suppress white spots and member stains by forming an image portion using a liquid having Martens hardness, which will be described later, increases.

In the image forming apparatuses according to the above-described first to sixth embodiments, the conveyed member contacts the plurality of heating members with the surface to which liquid is not applied, but is not limited to this. , the surface to which the liquid is applied may be in contact with the heating member. For example, in the first path, the surfaces to which the liquid is applied contact the plurality of heating members, and in the second path, the surfaces to which the liquid is applied contact the plurality of heating members. is mentioned. By drying the surface to which the liquid is not applied in the first path, image peeling due to contact between the undried image portion and the heating member is suppressed, and the surface to which the liquid is applied is directly heated in the second path. By doing so, a higher drying property can be obtained.
In the image forming apparatuses according to the first to seventh embodiments described above, a continuous form sheet is used as an example of a member to be conveyed. can also When a cut sheet is used as a member to be conveyed, any known method can be used as a method for conveying the cut sheet. For example, a method of conveying the cut sheet while holding both sides of the cut sheet between belts is preferable. By nipping the recording medium with the belt, it is possible to apply tension in the conveying direction, and it becomes possible to bring the recording medium into closer contact with the heating roller, thereby making it possible to improve drying efficiency.

<<Liquid>>
The liquid used in the image forming apparatus having the drying device of the present invention has a Martens hardness of 30 N/mm ² or more at 120° C. of a dry film formed from the liquid by the following preparation method [Method of preparation]
The liquid is coated on a glass plate, and the coated liquid is dried under reduced pressure at 100° C. for 3 hours to obtain a dry film with an average thickness of 5 μm.
Ink, which is one form of liquid, will be described below.

[Martens hardness]
Martens hardness is an index representing the hardness of a material obtained in an indentation depth test. In this test, a Vickers indenter is pressed into the material, and the load test force and the depth of indentation are continuously measured to obtain the relationship of "indentation depth - test force". Then, the Martens hardness is determined based on the slope of this curve in which the depth of indentation up to 50% and 90% of the maximum load test force is proportional to the square root of the load test force.

The Martens hardness of a dry film in the present application is measured using a dry film obtained by coating a liquid on a glass plate and drying it under reduced pressure at 100° C. for 3 hours. The liquid is applied so that the average thickness of the dry film after drying is 5 μm. The average means the average thickness at 10 arbitrary points of the dry film. After cooling the dried film to room temperature, it is heated to 120° C., and is applied with a Vickers indenter at a force of 0.5 [mN] for 10 seconds using a microhardness tester HM-2000 manufactured by Fisher Instruments. It can be measured by indenting, holding for 5 seconds, and withdrawing the indenter over 10 seconds.

The Martens hardness of the dry film measured by this method is 30 N/mm ² or more, preferably 35 N/mm ² or more, more preferably 50 N/mm ² or more. If it is 30 N/mm ² or more, the tack force in the area to which the liquid is applied on the conveyed member is low, and the mechanical strength is also high. Therefore, it is possible to suppress white spots caused by the contact of a member such as a contact guide member that contacts the region to which the liquid is applied. Further, as described above, when the contact guide member or the like contacts the area to which the liquid is applied, the area to which the liquid is applied is in a heated state. Therefore, in the present application, the Martens hardness of the dry film is measured at 120° C. in accordance with the actual situation. The Martens hardness of the dry film is preferably 120 N/mm ² or less, more preferably 117 N/mm ² or less, and even more preferably 89 N/mm ² or less. If it is 120 N/mm ² or less, the scratch resistance can be improved, and contamination of members can be suppressed.
Further, in this embodiment, in order to efficiently heat the member being conveyed, a plurality of heating members are provided in the conveying path, and contact guides are provided between adjacent heating members in the conveying path. It is preferable to have a plurality of members. At this time, the contact guide member comes into contact with the liquid-applied area on the conveyed member a plurality of times. Therefore, when such a drying apparatus is used, it is more preferable that the liquid applied to the member to be conveyed satisfies the Martens hardness range in order to suppress white spots.

Next, the ink having the above Martens hardness will be described. Martens hardness is particularly affected by the type of resin in the ink, the resin content, and the like. Ink compositions capable of realizing the Martens hardness described above are exemplified below.

<Organic solvent>
The organic solvent used in the present invention is not particularly limited, and any water-soluble organic solvent can be used. Examples thereof include polyhydric alcohols, ethers such as polyhydric alcohol alkyl ethers and polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines, and sulfur-containing compounds.
Specific examples of water-soluble organic solvents include ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 1,4-butane. Diol, 2,3-butanediol, 3-methyl-1,3-butanediol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol , 2,4-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 1,3-hexanediol, 2,5-hexanediol, 1,5-hexanediol, glycerin, 1,2,6-hexanetriol, 2-ethyl-1,3-hexanediol, ethyl-1,2,4-butanetriol, 1,2,3-butanetriol, 2,2,4-trimethyl- Polyhydric alcohols such as 1,3-pentanediol and petriol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene glycol monoethyl polyhydric alcohol alkyl ethers such as ether, polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone , 1,3-dimethyl-2-imidazolidinone, ε-caprolactam, nitrogen-containing heterocyclic compounds such as γ-butyrolactone, formamide, N-methylformamide, N,N-dimethylformamide, 3-methoxy-N,N- Amides such as dimethylpropionamide and 3-butoxy-N,N-dimethylpropionamide, amines such as monoethanolamine, diethanolamine, and triethylamine, sulfur-containing compounds such as dimethylsulfoxide, sulfolane, and thiodiethanol, propylene carbonate, and ethylene carbonate. etc.
It is preferable to use an organic solvent having a boiling point of 250° C. or less because it not only functions as a wetting agent but also provides good drying properties.

Polyol compounds having 8 or more carbon atoms and glycol ether compounds are also preferably used. Specific examples of polyol compounds having 8 or more carbon atoms include 2-ethyl-1,3-hexanediol and 2,2,4-trimethyl-1,3-pentanediol.
Specific examples of glycol ether compounds include polyhydric alcohol alkyls such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, and propylene glycol monoethyl ether. Ethers; polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, and the like.
A polyol compound having 8 or more carbon atoms and a glycol ether compound can improve ink permeability when paper is used as a recording medium.

In particular, when the ink contains a resin, N,N-dimethyl-β-butoxypropionamide, N,N-dimethyl-β-ethoxypropionamide, 3-ethyl-3-hydroxymethyloxetane, propylene glycol monomethyl ether is preferred. These may be used individually by 1 type, and may use 2 or more types together. By using these together with a resin, the film-forming property of the resin is promoted, and it becomes easy to make the Martens hardness of the dry film 30 N/mm ² or ^more . It is not limited to this solvent type. Resin content in ink and N,N-dimethyl-β-butoxypropionamide, N,N-dimethyl-β-ethoxypropionamide, 3-ethyl-3-hydroxymethyloxetane, and propylene glycol monomethyl in ink When the total content of ether and the mass ratio (resin content/content of the organic solvent) is 0.86 or more and 1.60 or less, the dry film has a Martens hardness of 30 N/mm ² or more. However, the means for achieving Martens hardness of 30 N/mm ² or more is not limited to this mass ratio.

The boiling point of the organic solvent is preferably 180°C or higher and 260°C or lower. When the boiling point is 180° C. or higher, the evaporation rate during drying can be appropriately adjusted, sufficient leveling can be performed, and scratch resistance can be improved. Further, when the temperature is 260° C. or less, the drying property does not deteriorate and the drying time does not become long. With the speeding up of printing technology in recent years, the time required for ink drying has become rate-determining, and it is necessary to shorten the drying time, so long drying is not preferable.

The content of the organic solvent in the ink is not particularly limited and can be appropriately selected according to the purpose. 20% by mass or more and 60% by mass or less is more preferable.

<Water>
The content of water in the ink is not particularly limited and can be appropriately selected according to the purpose. % to 60% by mass is more preferred.

<Color material>
The coloring material is not particularly limited, and pigments and dyes can be used.
An inorganic pigment or an organic pigment can be used as the pigment. These may be used individually by 1 type, and may use 2 or more types together. Mixed crystals may also be used.
Examples of pigments that can be used include black pigments, yellow pigments, magenta pigments, cyan pigments, white pigments, green pigments, orange pigments, glossy color pigments such as gold and silver, and metallic pigments.
As inorganic pigments, in addition to titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, and chrome yellow, carbon black produced by known methods such as contact method, furnace method, thermal method, etc. can be used.
Organic pigments include azo pigments, polycyclic pigments (e.g., phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, quinophthalone pigments, etc.). , dye chelates (eg, basic dye chelates, acid dye chelates, etc.), nitro pigments, nitroso pigments, aniline black, and the like. Among these pigments, those having good affinity with the solvent are preferably used. In addition, resin hollow particles and inorganic hollow particles can also be used.
Specific examples of pigments for black include carbon blacks (C.I. Pigment Black 7) such as furnace black, lamp black, acetylene black and channel black, or copper and iron (C.I. Pigment Black 11). , metals such as titanium oxide, and organic pigments such as aniline black (C.I. Pigment Black 1).
Further, for color, C.I. I. Pigment yellow 1, 3, 12, 13, 14, 17, 24, 34, 35, 37, 42 (yellow iron oxide), 53, 55, 74, 81, 83, 95, 97, 98, 100, 101, 104 , 108, 109, 110, 117, 120, 138, 150, 153, 155, 180, 185, 213, C.I. I. Pigment Orange 5, 13, 16, 17, 36, 43, 51, C.I. I. Pigment Red 1, 2, 3, 5, 17, 22, 23, 31, 38, 48:2, 48:2 (Permanent Red 2B (Ca)), 48:3, 48:4, 49:1, 52: 2, 53:1, 57:1 (brilliant carmine 6B), 60:1, 63:1, 63:2, 64:1, 81, 83, 88, 101 (red red), 104, 105, 106, 108 ( cadmium red), 112, 114, 122 (quinacridone magenta), 123, 146, 149, 166, 168, 170, 172, 177, 178, 179, 184, 185, 190, 193, 202, 207, 208, 209, 213, 219, 224, 254, 264, C.I. I. Pigment Violet 1 (rhodamine lake), 3, 5:1, 16, 19, 23, 38, C.I. I. Pigment Blue 1, 2, 15 (phthalocyanine blue), 15:1, 15:2, 15:3, 15:4 (phthalocyanine blue), 16, 17:1, 56, 60, 63, C.I. I. Pigment Green 1, 4, 7, 8, 10, 17, 18, 36, etc.
As dyes, acid dyes, direct dyes, reactive dyes, and basic dyes can be used without particular limitation, and may be used singly or in combination of two or more.
Examples of the dye include C.I. I. Acid Yellow 17, 23, 42, 44, 79, 142, C.I. I. Acid Red 52, 80, 82, 249, 254, 289, C.I. I. Acid Blue 9,45,249, C.I. I. Acid Black 1, 2, 24, 94, C.I. I. Food Black 1, 2, C.I. I. Direct Yellow 1, 12, 24, 33, 50, 55, 58, 86, 132, 142, 144, 173, C.I. I. Direct Red 1, 4, 9, 80, 81, 225, 227, C.I. I. Direct Blue 1, 2, 15, 71, 86, 87, 98, 165, 199, 202, C.I. I. Directed Black 19, 38, 51, 71, 154, 168, 171, 195, C.I. I. Reactive Red 14, 32, 55, 79, 249, C.I. I. and Reactive Black 3,4,35.

The content of the coloring material in the ink is preferably 0.1% by mass or more and 15% by mass or less, more preferably 1% by mass or more and 10% by mass, from the viewpoints of improving image density, good fixability, and ejection stability. It is below.

In order to disperse the pigment and obtain an ink, there are a method of introducing a hydrophilic functional group into the pigment to make it a self-dispersing pigment, a method of coating the surface of the pigment with a resin for dispersion, and a method of dispersing using a dispersant. method, etc.
As a method of making a self-dispersing pigment by introducing a hydrophilic functional group into a pigment, for example, a method of adding a functional group such as a sulfone group or a carboxyl group to a pigment (for example, carbon) to make it dispersible in water. is mentioned.
As a method of coating the surface of a pigment with a resin and dispersing it, there is a method of encapsulating the pigment in microcapsules to make it dispersible in water. This can be rephrased as a resin-coated pigment. In this case, all the pigments mixed in the ink need not be coated with a resin, and uncoated pigments or partially coated pigments may be dispersed in the ink as long as the effects of the present invention are not impaired. may be
Examples of the method of dispersing using a dispersant include a method of dispersing using a known low-molecular-weight dispersant and high-molecular-weight dispersant typified by surfactants.
As the dispersant, it is possible to use, for example, anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants, etc. depending on the pigment.
RT-100 (nonionic surfactant) manufactured by Takemoto Yushi Co., Ltd. and sodium naphthalenesulfonate formalin condensate can also be suitably used as a dispersant.
A dispersing agent may be used individually by 1 type, or may use 2 or more types together.

<Pigment dispersion>
Inks can be obtained by mixing materials such as water and organic solvents with pigments. Ink can also be produced by mixing a pigment, water, a dispersant, and the like to form a pigment dispersion, and then mixing materials such as water and an organic solvent.
The pigment dispersion is obtained by mixing and dispersing water, a pigment, a pigment dispersant, and optionally other components, and adjusting the particle size. Dispersion should be carried out using a disperser.
The particle diameter of the pigment in the pigment dispersion is not particularly limited, but the dispersion stability of the pigment is improved, and the image quality such as ejection stability and image density is improved. 500 nm or less is preferable, and 20 nm or more and 150 nm or less is more preferable. The particle size of the pigment can be measured using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrack Bell Co., Ltd.).
The content of the pigment in the pigment dispersion is not particularly limited and can be appropriately selected according to the purpose. % or more and 50 mass % or less is preferable, and 0.1 mass % or more and 30 mass % or less is more preferable.
The pigment dispersion is preferably degassed by filtering coarse particles with a filter, a centrifugal separator, or the like, if necessary.

<Resin>
The type of resin contained in the ink is not particularly limited and can be appropriately selected according to the purpose. resins, styrene-butadiene-based resins, vinyl chloride-based resins, acrylic-styrene-based resins, acrylic-silicone-based resins, and the like.
Resin particles made of these resins may also be used. Ink can be obtained by mixing resin particles in a resin emulsion state in which water is dispersed as a dispersion medium with a material such as a coloring material or an organic solvent. As the resin particles, appropriately synthesized ones may be used, or commercially available products may be used. Moreover, these may be used individually by 1 type, or may be used in combination of 2 or more types of resin particles.

Among these, urethane resin particles are preferred. The urethane resin particles have a large tack force, can form a strong dry film, and can improve scratch resistance, so that the problem of white spots can be suppressed. Furthermore, urethane resin particles having a glass transition temperature (Tg) of -20°C or higher and 70°C or lower can further improve scratch resistance.

Moreover, among the resin particles described above, the acrylic resin particles are excellent in abrasion resistance and ejection stability, and thus are preferably used in combination with the urethane resin particles.

The mass ratio (urethane resin particles/acrylic resin particles) of the content (% by mass) of the urethane resin particles with respect to the total amount of the ink and the content (% by mass) of the acrylic resin particles with respect to the total amount of the ink in the ink is 0. 1 or more and 0.5 or less are preferable. When the mass ratio (urethane resin particles/acrylic resin particles) is 0.1 or more and 0.5 or less, it becomes easy to make the Martens hardness of the dry film formed using the ink 30 N/mm ² or more. However, the means for increasing the Martens hardness to 30 N/mm ² or more is not limited to this resin mass ratio.

The volume average particle diameter of the resin particles is not particularly limited and can be appropriately selected according to the intended purpose. 200 nm or less is more preferable, and 10 nm or more and 100 nm or less is particularly preferable.
The volume average particle diameter can be measured, for example, using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrack Bell Co., Ltd.).

The content of the resin is not particularly limited and can be appropriately selected according to the purpose. However, from the viewpoint of fixability and storage stability of the ink, the content is 1% by mass or more and 30% by mass or less based on the total amount of the ink. is preferable, and 5% by mass or more and 20% by mass or less is more preferable.

The particle size of the solid content in the ink is not particularly limited and can be appropriately selected according to the purpose. is preferably 20 nm or more and 1000 nm or less, more preferably 20 nm or more and 150 nm or less. The solid content includes resin particles, pigment particles, and the like. The particle size can be measured using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrack Bell Co., Ltd.).

<Filler>
The ink may contain fillers. By including the filler, which has a higher hardness than other components in the ink, in the region to which the liquid is applied, it becomes easy to make the Martens hardness of the dry film 30 N/mm ² or more. Means for achieving 30 N/mm ² or more are not limited to fillers. In addition, since the area to which the liquid is applied contains the filler, the contact area between the area to which the liquid is applied and the member such as the contact guide member that contacts the area can be reduced, and white spots and contamination of the member can be suppressed. .
Examples of fillers include inorganic pigments, and specific examples include white carbon (fine powder silicic acid), iron oxides (red iron oxide, yellow iron oxide, iron black, etc.), iron powder, copper powder, calcium carbonate, Examples thereof include talc and aluminum powder, but white carbon (finely powdered silicic acid) with high hardness, iron oxides (red iron oxide, yellow iron oxide, iron black, etc.), iron powder, copper powder and the like are preferred. Considering that the filler affects the color of the ink, a white pigment is preferable, but a colored pigment such as iron oxide may be used as long as the color after addition is considered. The filler content is preferably 1.0% by mass or more and 5.0% by mass or less with respect to the total amount of the ink. From the viewpoint of good ejection properties, the volume average particle diameter (D90) is preferably 80 nm or more and 250 nm or less.

<Additive>
Surfactants, antifoaming agents, antiseptic antifungal agents, anticorrosive agents, pH adjusters, etc. may be added to the ink as necessary.

<Surfactant>
Any of silicone surfactants, fluorine surfactants, amphoteric surfactants, nonionic surfactants, and anionic surfactants can be used as surfactants.
The silicone-based surfactant is not particularly limited and can be appropriately selected depending on the purpose. Among them, those that do not decompose even at high pH are preferable. Those having an oxyethylene group or a polyoxyethylene polyoxypropylene group are particularly preferred because they exhibit good properties as water-based surfactants. As the silicone-based surfactant, a polyether-modified silicone-based surfactant can also be used, and examples thereof include compounds in which a polyalkylene oxide structure is introduced into the side chain of the Si portion of dimethylsiloxane.
Examples of fluorine-based surfactants include perfluoroalkylsulfonic acid compounds, perfluoroalkylcarboxylic acid compounds, perfluoroalkylphosphoric acid ester compounds, perfluoroalkylethylene oxide adducts, and perfluoroalkyl ether groups in side chains. Polyoxyalkylene ether polymer compounds are particularly preferred due to their low foaming properties. Examples of the perfluoroalkylsulfonic acid compound include perfluoroalkylsulfonic acid and perfluoroalkylsulfonate. Examples of the perfluoroalkylcarboxylic acid compounds include perfluoroalkylcarboxylic acids and perfluoroalkylcarboxylic acid salts. As the polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in a side chain, a sulfuric acid ester salt of a polyoxyalkylene ether polymer having a perfluoroalkyl ether group in a side chain, and a perfluoroalkyl ether group in a side chain Examples thereof include salts of polyoxyalkylene ether polymers. Counter ions of salts in these _{fluorosurfactants} include Li, Na, K, _NH4 , _NH3CH2CH2OH , _{NH2 ( CH2CH2OH} ) ₂ , and _{NH ( CH2CH2OH} ). ₃ and the like.
Examples of amphoteric surfactants include laurylaminopropionate, lauryldimethylbetaine, stearyldimethylbetaine, lauryldihydroxyethylbetaine and the like.
Nonionic surfactants include, for example, polyoxyethylene alkylphenyl ethers, polyoxyethylene alkyl esters, polyoxyethylene alkylamines, polyoxyethylene alkylamides, polyoxyethylene propylene block polymers, sorbitan fatty acid esters, polyoxyethylene sorbitan Examples include fatty acid esters and ethylene oxide adducts of acetylene alcohol.
Examples of anionic surfactants include polyoxyethylene alkyl ether acetates, dodecylbenzene sulfonates, laurates, and salts of polyoxyethylene alkyl ether sulfates.
These may be used individually by 1 type, or may use 2 or more types together.

（但し、一般式（Ｓ－１）式中、ｍ、ｎ、ａ、及びｂは、それぞれ独立に、整数を表わし、Ｒは、アルキレン基を表し、Ｒ’は、アルキル基を表す。）
上記のポリエーテル変性シリコーン系界面活性剤としては、市販品を用いることができ、例えば、ＫＦ－６１８、ＫＦ－６４２、ＫＦ－６４３（信越化学工業株式会社）、ＥＭＡＬＥＸ－ＳＳ－５６０２、ＳＳ－１９０６ＥＸ（日本エマルジョン株式会社）、ＦＺ－２１０５、ＦＺ－２１１８、ＦＺ－２１５４、ＦＺ－２１６１、ＦＺ－２１６２、ＦＺ－２１６３、ＦＺ－２１６４（東レ・ダウコーニング・シリコーン株式会社）、ＢＹＫ－３３、ＢＹＫ－３８７（ビックケミー株式会社）、ＴＳＦ４４４０、ＴＳＦ４４５２、ＴＳＦ４４５３（東芝シリコン株式会社）などが挙げられる。 The silicone-based surfactant is not particularly limited and can be appropriately selected depending on the intended purpose. Examples include polydimethylsiloxane modified at both chain ends, and polyether-modified silicone-based surfactants having polyoxyethylene groups or polyoxyethylene-polyoxypropylene groups as modifying groups exhibit excellent properties as water-based surfactants. preferable.
As such a surfactant, an appropriately synthesized one may be used, or a commercially available product may be used. Commercially available products are available from, for example, BYK Chemie Co., Ltd., Shin-Etsu Chemical Co., Ltd., Dow Corning Toray Silicone Co., Ltd., Nihon Emulsion Co., Ltd., Kyoeisha Chemical Co., Ltd., and the like.
The above polyether-modified silicone-based surfactant is not particularly limited and can be appropriately selected according to the purpose. Examples include those introduced into the side chain of the Si portion of siloxane.

(However, in general formula (S-1), m, n, a, and b each independently represent an integer, R represents an alkylene group, and R' represents an alkyl group.)
Commercially available products can be used as the above polyether-modified silicone-based surfactants. 1906EX (Japan Emulsion Co., Ltd.), FZ-2105, FZ-2118, FZ-2154, FZ-2161, FZ-2162, FZ-2163, FZ-2164 (Dow Corning Toray Silicone Co., Ltd.), BYK-33, BYK-387 (BYK-Chemie Corporation), TSF4440, TSF4452, TSF4453 (Toshiba Silicon Co., Ltd.) and the like.

上記一般式（Ｆ－１）で表される化合物において、水溶性を付与するためにｍは０～１０の整数が好ましく、ｎは０～４０の整数が好ましい。

上記一般式（Ｆ－２）で表される化合物において、ＹはＨ、又はＣｍＦ_２ｍ＋１でｍは１～６の整数、又はＣＨ_２ＣＨ（ＯＨ）ＣＨ_２－ＣｍＦ_２ｍ＋１でｍは４～６の整数、又はＣｐＨ_２ｐ＋１でｐは１～１９の整数である。ｎは１～６の整数である。ａは４～１４の整数である。
上記のフッ素系界面活性剤としては市販品を使用してもよい。この市販品としては、例えば、サーフロンＳ－１１１、Ｓ－１１２、Ｓ－１１３、Ｓ－１２１、Ｓ－１３１、Ｓ－１３２、Ｓ－１４１、Ｓ－１４５（いずれも、旭硝子株式会社製）；フルラードＦＣ－９３、ＦＣ－９５、ＦＣ－９８、ＦＣ－１２９、ＦＣ－１３５、ＦＣ－１７０Ｃ、ＦＣ－４３０、ＦＣ－４３１（いずれも、住友スリーエム株式会社製）；メガファックＦ－４７０、Ｆ－１４０５、Ｆ－４７４（いずれも、大日本インキ化学工業株式会社製）；ゾニール（Ｚｏｎｙｌ）ＴＢＳ、ＦＳＰ、ＦＳＡ、ＦＳＮ－１００、ＦＳＮ、ＦＳＯ－１００、ＦＳＯ、ＦＳ－３００、ＵＲ、キャプストーンＦＳ－３０、ＦＳ－３１、ＦＳ－３１００、ＦＳ－３４、ＦＳ－３５（いずれも、Ｃｈｅｍｏｕｒｓ社製）；ＦＴ－１１０、ＦＴ－２５０、ＦＴ－２５１、ＦＴ－４００Ｓ、ＦＴ－１５０、ＦＴ－４００ＳＷ（いずれも、株式会社ネオス社製）、ポリフォックスＰＦ－１３６Ａ，ＰＦ－１５６Ａ、ＰＦ－１５１Ｎ、ＰＦ－１５４、ＰＦ－１５９（オムノバ社製）、ユニダインＤＳＮ－４０３Ｎ（ダイキン工業株式会社製）などが挙げられ、これらの中でも、良好な印字品質、特に発色性、紙に対する浸透性、濡れ性、均染性が著しく向上する点から、Ｃｈｅｍｏｕｒｓ社製のＦＳ－３１００、ＦＳ－３４、ＦＳ－３００、株式会社ネオス製のＦＴ－１１０、ＦＴ－２５０、ＦＴ－２５１、ＦＴ－４００Ｓ、ＦＴ－１５０、ＦＴ－４００ＳＷ、オムノバ社製のポリフォックスＰＦ－１５１Ｎ及びダイキン工業株式会社製のユニダインＤＳＮ－４０３Ｎが特に好ましい。 As the fluorosurfactant, a fluorine-substituted compound having 2 to 16 carbon atoms is preferable, and a fluorine-substituted compound having 4 to 16 carbon atoms is more preferable.
Examples of fluorine-based surfactants include perfluoroalkyl phosphate ester compounds, perfluoroalkyl ethylene oxide adducts, and polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups in side chains. Among these, a polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in a side chain is preferable because of its low foamability, and in particular, fluorine-based compounds represented by general formulas (F-1) and (F-2) Surfactants are preferred.

In the compound represented by the general formula (F-1), m is preferably an integer of 0 to 10 and n is preferably an integer of 0 to 40 in order to impart water solubility.

In the compound represented by the above general formula (F-2), Y is H, or CmF _2m+1 and m is an integer of 1 to 6, or CH ₂ CH(OH)CH ₂ -CmF _2m+1 and m is 4 to 6 Integer, or CpH _2p+1 where p is an integer from 1-19. n is an integer of 1-6. a is an integer from 4 to 14;
Commercially available products may be used as the fluorosurfactant. Examples of commercially available products include Surflon S-111, S-112, S-113, S-121, S-131, S-132, S-141, and S-145 (all manufactured by Asahi Glass Co., Ltd.); Fleurard FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, FC-431 (both manufactured by Sumitomo 3M); Megafac F-470, F -1405, F-474 (both manufactured by Dainippon Ink and Chemicals); Zonyl TBS, FSP, FSA, FSN-100, FSN, FSO-100, FSO, FS-300, UR, Capstone FS-30, FS-31, FS-3100, FS-34, FS-35 (all manufactured by Chemours); FT-110, FT-250, FT-251, FT-400S, FT-150, FT- 400SW (all manufactured by Neos Co., Ltd.), Polyfox PF-136A, PF-156A, PF-151N, PF-154, PF-159 (manufactured by Omnova), Unidyne DSN-403N (manufactured by Daikin Industries, Ltd.) Among these, Chemours FS-3100, FS-34, FS- 300, FT-110, FT-250, FT-251, FT-400S, FT-150, FT-400SW manufactured by Neos Co., Ltd., Polyfox PF-151N manufactured by Omnova Co., Ltd. and Unidyne DSN- manufactured by Daikin Industries, Ltd. 403N is particularly preferred.

The content of the surfactant in the ink is not particularly limited and can be appropriately selected according to the purpose. % or more and 5 mass % or less is preferable, and 0.05 mass % or more and 5 mass % or less is more preferable.

<Antifoaming agent>
The antifoaming agent is not particularly limited, and examples thereof include silicone antifoaming agents, polyether antifoaming agents, and fatty acid ester antifoaming agents. These may be used individually by 1 type, or may use 2 or more types together. Among these, silicone-based antifoaming agents are preferred because of their excellent foam breaking effect.

<Preservative and antifungal agent>
The antiseptic and antifungal agent is not particularly limited, and examples thereof include 1,2-benzisothiazolin-3-one.

<Antirust agent>
The rust inhibitor is not particularly limited, and examples thereof include acidic sulfites and sodium thiosulfate.

<pH adjuster>
The pH adjuster is not particularly limited as long as it can adjust the pH to 7 or higher, and examples thereof include amines such as diethanolamine and triethanolamine.

The physical properties of the ink are not particularly limited and can be appropriately selected depending on the intended purpose. For example, viscosity, surface tension, pH and the like are preferably within the following ranges.
The viscosity of the ink at 25° C. is preferably 5 mPa·s or more and 30 mPa·s or less, more preferably 5 mPa·s or more and 25 mPa·s or less, from the viewpoint of improving the print density and character quality and obtaining good ejection properties. more preferred. Here, the viscosity can be measured using, for example, a rotational viscometer (RE-80L manufactured by Toki Sangyo Co., Ltd.). Measurement conditions are 25° C., standard cone rotor (1°34′×R24), sample liquid volume 1.2 mL, rotation speed 50 rpm, 3 minutes.
The surface tension of the ink is preferably 35 mN/m or less, more preferably 32 mN/m or less at 25° C., from the viewpoint that the ink is appropriately leveled on the recording medium and the drying time of the ink is shortened.
The pH of the ink is preferably from 7 to 12, more preferably from 8 to 11, from the viewpoint of preventing corrosion of metal members in contact with the liquid.

Although the liquid is preferably ink, it is not limited to this, and may be, for example, a pretreatment liquid, a posttreatment liquid, or the like.
The pretreatment liquid is a liquid that is applied to a conveyed member before the ink is applied, and preferably has a function of aggregating components such as a coloring material in the ink. The pretreatment liquid contains organic solvents, water, resins, additives such as surfactants, coagulants, and the like. Additives such as organic solvents, water, resins, and surfactants are the same as those used in the ink, so description thereof will be omitted. As the flocculant, a known flocculant can be used as appropriate, and for example, it can be selected from polyvalent metal salts, organic acids, cationic polymers, and the like.
The post-treatment liquid is a liquid that is applied to the conveyed member after the ink has been applied, and preferably has a function of protecting the image portion formed with the ink. The post-treatment liquid contains additives such as organic solvents, water, resins, fillers, and surfactants. Additives such as organic solvents, water, resins, fillers, and surfactants are the same as those used in the ink, so descriptions thereof will be omitted.
In the present embodiment, the above-mentioned "white spot" includes peeling of the coating film formed with the ink and peeling of the coating film formed with the pre-treatment liquid or the post-treatment liquid.

<<Members to be conveyed>>
The recording medium, which is an example of the member to be conveyed, is not particularly limited and can be appropriately selected according to the purpose. Examples include cut paper and continuous paper. Note that the recording medium means a medium to which ink and various processing liquids can adhere even temporarily.
The recording medium is not limited to those used as general recording media, and wallpaper, floor materials, building materials such as tiles, cloth for clothing such as T-shirts, textiles, leather, and the like can be used as appropriate. Ceramics, glass, metal, etc. can also be used by adjusting the configuration of the path for conveying the recording medium.
In particular, the recording medium to which the effect of the present invention can be obtained comprises a support, a coating layer provided on at least one side of the support, and, if necessary, other layers. and a recording medium having

In the recording medium having the support and the coating layer, the transfer amount of pure water to the recording medium at a contact time of 100 ms measured by a dynamic scanning liquid absorption meter is 2 mL/m ² or more and 35 mL/m ² or less. and preferably 2 mL/m ² or more and 10 mL/m ² or less.
If the transfer amount of the ink and pure water at the contact time of 100 ms is too small, beading may easily occur. There is
The transfer amount of pure water to the recording medium at a contact time of 400 ms measured by a dynamic scanning liquid absorption meter is 3 mL/m ² or more and 40 mL/m ² or less, and 3 mL/m ² or more and 10 mL/m ² or less. preferable.
If the transfer amount at the contact time of 400 ms is small, the drying property is insufficient, and white spots and stains on the member may easily occur. Gloss tends to be low in some cases. The amounts of pure water transferred to the recording medium at the contact times of 100 ms and 400 ms can both be measured on the side of the recording medium having the coating layer.

Here, the dynamic scanning absorptometer (DSA, Paper-Paper Technical Association, Vol. 48, May 1994, pp. 88-92, Shigenori Kuga) is a liquid absorption in an extremely short time It is a device that can measure quantity accurately. The dynamic scanning liquid absorption meter directly reads the speed of liquid absorption from the movement of the meniscus in the capillary. is automatically changed, and the measurement is automated by a method of measuring only the required number of points on one sample.
A liquid supply head to the paper sample is connected to the capillary through a Teflon (registered trademark) tube, and the position of the meniscus in the capillary is automatically read by an optical sensor. Specifically, a dynamic scanning liquid absorption meter (K350 series D type, manufactured by Kyowa Seiko Co., Ltd.) can be used to measure the transfer amount of pure water or ink.
The amount of transfer at a contact time of 100 ms and a contact time of 400 ms can be obtained by interpolation from measured values of the amount of transfer at contact times adjacent to each contact time.

<Records>
A recorded matter has an image formed using the above ink on a conveyed member. The conveyed member can be recorded by an inkjet recording apparatus and an inkjet recording method to obtain a recorded matter.

Examples of the present invention will be described below, but the present invention is not limited to these examples.

<Preparation example of pigment dispersion>
(Adjustment of cyan pigment dispersion)
Pigment Blue 15:3 (manufactured by Dainichiseika Kogyo Co., Ltd., Chromophine Blue) 20 g, 20 mmol of the compound of the following structural formula (1), and 200 mL of ion-exchanged high-purity water are mixed at room temperature with a Silverson mixer (6,000 rpm). and a slurry was obtained. If the pH of the resulting slurry was higher than 4, 20 mmol of nitric acid was added. After 30 minutes, sodium nitrite (20 mmol) dissolved in a small amount of ion-exchanged high purity water was slowly added to the above mixture. Further, the mixture was stirred while being heated at 60° C. and allowed to react for 1 hour to produce a modified pigment in which a compound represented by the following structural formula (1) was added to Pigment Blue. The pH was then adjusted to 10 with an aqueous NaOH solution, and after 30 minutes a modified pigment dispersion was obtained. The modified pigment dispersion comprises a pigment having at least one geminal bisphosphonic acid group or a sodium salt of a geminal bisphosphonic acid group. Next, the modified pigment dispersion and ion-exchanged high-purity water were subjected to ultrafiltration using a dialysis membrane, followed by ultrasonic dispersion to obtain a cyan pigment dispersion having a pigment concentration of 15% by mass.

(Adjustment of magenta pigment dispersion)
In Preparation Example of Cyan Pigment Dispersion, Pigment Blue 15:3 was changed to Pigment Red 122 (manufactured by Clariant Japan Co., Ltd., Toner Magenta EO02). % by weight magenta pigment dispersion was obtained.

<Ink preparation example>
(Adjustment of ink 1)
Ink 1 was prepared by mixing and stirring the following formulation and filtering through a 0.2 μm polypropylene filter. Regarding the content of each component, the amount of solid content is indicated for the component indicated as solid content, and the total addition amount is indicated for the component not indicated as solid content. Further, the total amount of ink 1 is 100 parts by mass.
・ Cyan pigment dispersion 45.0 parts by mass ・ Urethane resin particles 1 (manufactured by Mitsui Chemicals, Inc., trade name: Takelac W6110, glass transition temperature (Tg): -20 ° C.) 2.0 parts by mass (solid content)
・ Styrene acrylic resin particles (manufactured by DIC, trade name: GRANDOL PP-1000EF) 5.0 parts by mass (solid content)
・N,N-dimethyl-β-butoxypropionamide 5.0 parts by mass ・Diethylene glycol 15.0 parts by mass ・Zonyl FS-300 2.0 parts by mass ・Ion-exchanged water remaining amount

[Evaluation of Martens hardness]
Next, the ink 1 was coated on a glass plate and dried under reduced pressure at 100° C. for 3 hours to form a dry film having an average thickness of 5 μm. In addition, the average was taken as the average of the thickness at 10 arbitrary points of the dry film. After cooling the dried film to room temperature, it is heated to 120° C., and is applied with a Vickers indenter at a force of 0.5 [mN] for 10 seconds using a microhardness tester HM-2000 manufactured by Fisher Instruments. The indenter was pushed in, held for 5 seconds, and the indenter was pulled out over 10 seconds to measure the Martens hardness, which was 66 N/mm ² .

(Adjustment of inks 2 to 11)
Inks 2 to 11 were prepared in the same manner as Ink 1, except that the composition and content (% by mass) shown in Table 1 below were changed. The contents of the urethane resin particles and the acrylic resin particles represent the solid content, and the other components represent the total addition amount. In addition, using the prepared inks 2 to 11, the Martens hardness was measured in the same manner as for ink 1. The results are shown in Table 1 below.

In Table 1 above, the product names of the components, the names of the manufacturers, and the preparation method of the white carbon pigment dispersion are as follows.
- Urethane resin particles 1 (manufactured by Mitsui Chemicals, Inc., trade name: Takelac W6110, glass transition temperature (Tg): -20 ° C.)
- Urethane resin particles 2 (manufactured by Mitsui Chemicals, Inc., trade name: Takelac W6061, glass transition temperature (Tg): 25 ° C.)
- Urethane resin particles 3 (manufactured by Mitsui Chemicals, Inc., product name: Takelac W6010, glass transition temperature (Tg): 90 ° C.)
・ Styrene acrylic resin particles (manufactured by DIC, trade name: GRANDOL PP-1000EF)
・Acrylic silicone resin particles (manufactured by Toagosei Co., Ltd., trade name: Saimac US480)
・ Zonyl FS-300 (manufactured by Dupont)
・ TEGO WET-270 (manufactured by Evonik)

(Adjustment of white carbon pigment dispersion)
In the preparation example of the cyan pigment dispersion, pigment blue 15:3 was changed to a white carbon pigment (manufactured by Nippon Silica Co., Ltd., Nipsil) in the same manner as in the preparation example of the cyan pigment dispersion to obtain a pigment concentration of 15% by mass. A white carbon pigment dispersion was obtained.

<Formation and Drying of Region to which Liquid is Applied>
(Example 1)
Ink 1 is installed in the image forming apparatus shown in FIG. 1 equipped with the drying device shown in FIG. did The image area was formed by forming a solid image with a resolution of 1,200 dpi. Lumi Art Gloss 90 gsm roll paper (manufactured by Stora Enso, paper width 520.7 mm) was used as the recording medium.
The temperature of the image portion when the contact guide roller contacts the image portion and the surface shape of the contact guide roller are set as follows.
・Temperature of image area: 98°C
·Surface shape: uneven The temperature of the image portion in contact with the contact guide roller was measured using a non-contact thermometer (ES1B, manufactured by Omron Co., Ltd.). Further, the unevenness of the surface shape of the contact guide roller was created by covering the contact guide roller with a tape-like member to which substantially spherical glass was fixed. The diameter of the roughly spherical bodies varied and was in the range of 20-200 μm.

(Examples 2-12, Comparative Examples 1-4)
Formation of image areas of Examples 2 to 12 and Comparative Examples 1 to 4 was carried out in the same manner as in Example 1, except that the ink, the temperature of the image area, and the surface shape of the image area were changed as shown in Table 2 below. And the image area was dried.
Regarding the surface shape shown in Table 2 below, the term "flat surface" refers to the case where the contact guide roller is not covered with the tape-shaped member, and means that the surface shape does not have unevenness.

The image areas obtained through the formation and drying of the image areas in Examples 1 to 12 and Comparative Examples 1 to 4 were evaluated for white spots and scratch resistance according to the methods and evaluation criteria shown below.

[Evaluation of white spots]
The image area obtained through the formation of the image area and the drying of the image area was observed with an optical microscope (×50) and visually, and the state of image peeling was classified according to the following evaluation criteria and white spots were evaluated. In addition, the case where it was B or more was made into practical use. The results are shown in Table 2 below.
(Evaluation criteria)
A: Image peeling cannot be confirmed with an optical microscope (×50) B: Image peeling can be confirmed with an optical microscope (×50) but cannot be visually confirmed C: Image peeling can be visually confirmed

[Evaluation of scratch resistance]
A piece of paper (Lumi Art Gloss, 90 gsm) cut into a 1.2 cm square was used to rub the image 20 times on the image area obtained through the formation of the image area and the drying of the image area. The ink stain transferred to the rubbed paper was measured with a reflective color spectrophotometric densitometer (manufactured by X-Rite), and the density of the ink stain was calculated by subtracting the background color of the rubbed paper. The calculated densities of the ink stains were classified based on the following evaluation criteria to evaluate the abrasion resistance. In addition, it is preferable in it being more than B. The results are shown in Table 2 below.
(Evaluation criteria)
A: Density of ink contamination is less than 0.1 B: Density of ink contamination is 0.1 or more and less than 0.2 C: Density of ink contamination is 0.2 or more

10 contact heating means 11A to 11J heating roller (first heating member)
12 heating drum (second heating member)
13A to 13J contact guide rollers 17A to 17C guide rollers 101 liquid applying unit 103 conveying unit 104 drying device 110 continuous paper (conveyed member)

JP 2014-152964 A

Claims (21)

ink and
ink containing means for containing the ink;
ink applying means for applying the ink to continuous paper;
In an image forming apparatus comprising a drying device,
The drying device is a drying device for drying the continuous paper,
a plurality of heating members arranged side by side in the conveying direction of the continuous form for contacting the continuous form and heating the continuous form;
a transport path along which the continuous paper is transported while being in contact with the plurality of heating members;
The transport route is
a first path through which the continuous form is conveyed while being in contact with the plurality of heating members;
a second path along which the continuous form is conveyed while contacting again the at least one heating member with which it was contacted on the first path;
a contact guide member that guides the continuous paper so as to come into contact with the heating member when the continuous paper is conveyed on the second path;
the contact guide member contacts the inked area of the continuous paper;
a drying device in which the area to which the ink is applied has a temperature of 60° C. or more and 120° C. or less when contacting the contact guide member;
The ink has a Martens hardness of 30 N/mm at 120° C. of a dry film prepared from the ink by the following preparation method. ² An image forming apparatus using the above ink.
[How to make]
The ink is coated on a glass plate, and the coated ink is dried under reduced pressure at 100° C. for 3 hours to obtain a dry film with an average thickness of 5 μm. the plurality of heating members are arranged side by side in a curved or arcuate shape,
the first path is an outer path of the plurality of heating members arranged in a curved or arc shape;
2. The image forming apparatus according to claim 1, wherein the second path is an inner path of the plurality of heating members arranged curvedly or arcuately. 3. The image forming apparatus according to claim 1 , wherein the contact guide member is arranged between the adjacent heating members. 4. The image forming apparatus according to claim 1 , wherein a plurality of said heating members are arranged between said adjacent contact guide members. 5. The contact guide member is movable between a first position where the continuous paper is pressed against the heating member and a second position where the continuous paper is not pressed against the heating member. 1. The image forming apparatus according to claim 1 . 6. The image forming apparatus according to claim 1 , wherein the contact guide member has an uneven structure on its surface. The image forming apparatus according to any one of claims 1 to 6 , wherein the contact guide member has a substantially spherical body having a diameter of 20 µm or more and 200 µm or less on its surface. The ink contains urethane resin and acrylic resin,
8. A mass ratio of the content of the urethane resin to the content of the acrylic resin in the ink (content of urethane resin/content of acrylic resin) is 0.1 or more and 0.5 or less. The image forming apparatus according to any one of the items. The image forming apparatus according to any one of claims 1 to 8 , wherein the Martens hardness is 35 N/ ^mm2 or more and 120 N/ ^mm2 or less. The image forming apparatus according to any one of claims 1 to 9 , wherein the heating member arranged furthest downstream in the conveying direction in the first path has the largest diameter among the diameters of the plurality of heating members. . ink and
ink containing means for containing the ink;
a first ink applicator for applying the ink to the first surface of the continuous paper ;
a first drying device disposed on the downstream side of the first ink applying means in the conveying direction;
a second ink applying means disposed downstream of the first drying device in the conveying direction and applying ink to a second surface of the continuous paper opposite to the first surface;
and a second drying device disposed downstream of the second ink applying device in the conveying direction,
The first drying device and the second drying device are drying devices for drying the continuous paper,
a plurality of heating members arranged side by side in the conveying direction of the continuous form for contacting the continuous form and heating the continuous form;
a transport path along which the continuous paper is transported while being in contact with the plurality of heating members;
The transport route is
a first path through which the continuous form is conveyed while being in contact with the plurality of heating members;
a second path along which the continuous form is conveyed while contacting again the at least one heating member with which it was contacted on the first path;
a contact guide member that guides the continuous paper so as to come into contact with the heating member when the continuous paper is conveyed on the second path;
the contact guide member contacts the inked area of the continuous paper;
a drying device in which the area to which the ink is applied has a temperature of 60° C. or more and 120° C. or less when contacting the contact guide member;
In the first drying device, the second surface of the continuous paper comes into contact with the plurality of heating members on the first path,
In the second drying device, the first surface of the continuous paper comes into contact with the plurality of heating members on the first path,
The image forming apparatus, wherein the ink has a Martens hardness of 30 N/mm ² or more at 120° C. of a dry film produced from the ink by the following production method.
[How to make]
The ink is coated on a glass plate, and the coated ink is dried under reduced pressure at 100° C. for 3 hours to obtain a dry film with an average thickness of 5 μm. the plurality of heating members are arranged side by side in a curved or arcuate shape,
the first path is an outer path of the plurality of heating members arranged in a curved or arc shape;
12. The image forming apparatus according to claim 11, wherein the second path is an inner path of the plurality of heating members arranged in a curved or arc shape . 13. The image forming apparatus according to claim 11, wherein the contact guide member is arranged between the adjacent heating members. 14. The image forming apparatus according to any one of claims 11 to 13, wherein a plurality of said heating members are arranged between said adjacent contact guide members. 15. The contact guide member is movable between a first position that presses the continuous paper against the heating member and a second position that does not press the continuous paper against the heating member. 1. The image forming apparatus according to claim 1. 16. The image forming apparatus according to claim 11, wherein the contact guide member has an uneven structure on its surface. 17. The image forming apparatus according to any one of claims 11 to 16, wherein the contact guide member has a substantially spherical body with a diameter of 20 µm or more and 200 µm or less on its surface. The ink contains urethane resin and acrylic resin,
18. A mass ratio of the content of the urethane resin to the content of the acrylic resin in the ink (content of urethane resin/content of acrylic resin) is 0.1 or more and 0.5 or less. The image forming apparatus according to any one of . The image forming apparatus according to any one of Claims 11 to 18, wherein the Martens hardness is 35 N/ ^mm2 or more and 120 N/mm2 ^or less. 20. The image forming apparatus according to any one of claims 11 to 19, wherein the heating member arranged furthest downstream in the conveying direction in the first path has the largest diameter among the diameters of the plurality of heating members. . The ink contained in the image forming apparatus according to any one of claims 1 to 20,
The Martens hardness at 120° C. of a dry film prepared from the ink by the following preparation method is 30 N/mm. ² Ink that is more than that.
[How to make]
The ink is coated on a glass plate, and the coated ink is dried under reduced pressure at 100° C. for 3 hours to obtain a dry film with an average thickness of 5 μm.

Images