JP2001088334A - Recording method and recording device - Google Patents

Abstract

(57) Abstract: A recording liquid in contact with and held by a transfer unit is discharged or vaporized, and is transferred to a transfer target disposed opposite to the transfer unit, and a predetermined image or the like is transferred to the transfer target. Provided is a recording method and a recording apparatus in which a recording liquid in a transfer section is stably held so as to perform good recording. A liquid-repellent surface is formed by providing a fluororesin film on an upper surface of an ink dam, whereby ink held by a transfer unit is separated from a boundary between the ink and a liquid-repellent surface. The meniscus 29 is formed stably, and in this state, it is ejected by microbubbles or the like generated by heating by the heater 19, and good printing can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for ejecting or vaporizing a recording liquid held in contact with a transfer section and transferring the recording liquid to a transfer object disposed opposite the transfer section. And a recording apparatus for forming an image or the like.

[0002]

2. Description of the Related Art In recent years, an on-demand type ink jet type color printer has rapidly spread to individuals or small offices called "small office home offices".

[0003] On-demand type ink jet color printers are excellent in compatibility with plain paper and resolution, but have significant drawbacks in recording photo images. That is, since the minimum droplet size is about 10 picoliters, it is fundamentally difficult to express a density modulation of 10 steps or more in a unit pixel, so that the image quality is inferior to a silver halide photograph. Since the area of the unit pixel is reduced to improve the image quality, the recording time becomes very long.

Accordingly, in order to solve the drawbacks of the known thermal mode ink jet system, for example, Japanese Patent Application Laid-Open No.
As described in JP-A-64656, a capillary structure having a typical size of 1 to 10 μm is formed in a recording portion, ink containing a vaporizable dye is introduced into the capillary structure, and the capillary structure is formed according to image information. A thermal transfer recording system has been proposed in which the ink is vaporized by the applied heat or adhered and fixed as particles having a size of 1 picoliter or less to the opposing photographic paper via a gap to form an image.

[0005] In particular, the mechanism of discharging ink particles of 1 picoliter or less is that one or more bubbles having a diameter of 20 µm or less are formed in the capillary structure by boiling of the ink by heating, and the pressure due to the expansion of the bubbles is increased. The ink in the capillary structure is ejected as particles having a diameter of 10 μm or less due to the absence of a nozzle or a hole called an orifice for defining the size of the ink particles, and the ejection of the ink particles is caused by the contraction of bubbles. By not doing so, it can be distinguished from the known thermal mode inkjet system.

Since the size of a unit ink particle of this thermal transfer recording system is less than 1 picoliter, it is possible to perform fine density modulation within a unit pixel which cannot be realized by a known thermal mode on-demand type ink jet system.
In addition, by applying the semiconductor process, 300 dpi
The printer head of the thermal transfer recording system having the above-described resolution and a recording unit of 1000 or more can be easily manufactured, and can achieve high-speed image recording.

[0007]

However, it has been found that this thermal transfer recording system has the above-mentioned excellent characteristics and also has a problem to be improved.

First, the meniscus formed between the ink liquid layer and the atmosphere is not defined around a hole called a nozzle or an orifice as in a known ink jet system. Fluctuates easily, and the thickness of the ink on the heating means changes, so that the thermal energy required for ejection changes. As a result, density unevenness occurs between dots of the recording head. In addition, the thickness of the ink layer on the recording section becomes thicker, and the energy required to obtain the same density increases.

Second, as the number of prints increases, thermal degradation of the ink adheres to the capillary structure of the recording portion, and the contact angle of the surface of the capillary structure with ink may change significantly. In such a situation, a local meniscus changes during recording around the capillary structure, and the print density fluctuates with time.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a recording method and a recording apparatus which can stably hold a recording liquid in a transfer portion and perform good recording.

[0011]

In other words, the present invention provides a method for discharging or vaporizing a recording liquid in contact with and held by a transfer section and transferring the recording liquid to a transfer target disposed opposite to the transfer section.
A recording method in which the contact angle between the outer region of the transfer section and the recording liquid at 25 ° C. is at least 20 ° greater than the contact angle between the transfer section and the recording liquid at 25 ° C. 1
Recording method. ).

According to the first recording method of the present invention, at 25 ° C.
Since the respective contact angles of the transfer portion and the outer region of the transfer portion with respect to the recording liquid in the above step are larger by 20 ° or more in the outer region of the transfer portion than in the transfer portion, the recording liquid is transferred to the outer region of the transfer portion. Since the outflow is prevented and the meniscus is formed stably, the recording liquid is stably held at a predetermined thickness in the transfer portion, and as a result, the recording density is stable even at low energy and the recording density is uniform. It can be performed.

The present invention is also directed to a method for discharging or vaporizing a recording liquid in contact with and held by a transfer unit and transferring the recording liquid to an object to be transferred disposed opposite to the transfer unit. A contact angle at 25 ° C .; and a contact angle between the thermally degraded substance attached to the surface of the transfer portion during the recording operation and the recording liquid;
(Hereinafter, referred to as a second recording method of the present invention) in which the absolute value of the difference is 10 ° or less.

According to the second recording method of the present invention, the absolute value of the difference between the contact angle of the transfer portion and the thermally degraded substance attached to the surface of the transfer portion with respect to the recording liquid at 25 ° C. is 10 ° or less. Therefore, even if a substance such as a thermal degradation product of the recording liquid adheres to the surface of the transfer part during the recording operation, the contact angle of the recording liquid does not change so much. And a change in density over time is small, and recording can be performed at a stable transfer density.

Further, according to the present invention, there is provided a recording apparatus configured to discharge or vaporize a recording liquid held in contact with a transfer section and to transfer the recording liquid to a transfer target disposed opposite to the transfer section. 25 between the outer region of the transfer portion and the recording liquid
The transfer portion and the transfer portion outside region are formed such that a contact angle at 25 ° C. is larger than a contact angle between the transfer portion and the recording liquid at 25 ° C. by 20 ° or more. (Hereinafter, referred to as a first recording apparatus of the present invention).

According to the first recording apparatus of the present invention, since the apparatus is based on the above-mentioned first recording method of the present invention, the same effect as that of the first recording method can be obtained and the reproducibility is high. A recording device can be provided.

Further, according to the present invention, there is provided a recording apparatus configured to discharge or vaporize a recording liquid held in contact with a transfer section and to transfer the recording liquid to a transfer target disposed opposite to the transfer section. The absolute value of the difference between the contact angle between the transfer portion and the recording liquid at 25 ° C .; and the contact angle between the thermally degraded substance attached to the transfer portion surface during the recording operation and the recording liquid is 10 ° or less. The present invention relates to a recording apparatus (hereinafter, referred to as a second recording apparatus of the present invention).

According to the second recording apparatus of the present invention, since the apparatus is based on the above-described second recording method of the present invention, the same effect as that of the second recording method can be obtained and the reproducibility is high. A recording device can be provided.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described.

In the above-described first recording method and recording apparatus of the present invention, the transfer is performed so that the recording liquid is not contacted on the side opposite to the supply port of the recording liquid to the transfer section having a capillary structure. It is preferable that an outer region of the recording liquid is provided, and a meniscus of the recording liquid is defined by a boundary between the transfer liquid outer region and the recording liquid.

Then, one or two or more bubbles having a diameter of 20 μm or less are formed in the recording liquid in the capillary structure by boiling due to heating, and the recording liquid in the capillary structure is formed by the pressure due to the expansion of the bubbles. It is desirable to discharge as particles having a diameter of 10 μm or less.

In this case, the surface of the outer region of the transfer portion is coated with a fluororesin (fluorine atom content is preferably 2% by weight or more: the same applies hereinafter), diamond-like carbon or a mixture of nickel and fluororesin fine particles. Then, a lyophobic treatment is performed on the recording liquid, and the difference in the contact angle between the outer region of the transfer unit and the transfer unit at 25 ° C. with the recording liquid at the outer region is 20 ° or more (preferably). Is 3
(0 ° or more).

In the above-described second recording method and recording apparatus of the present invention, the recording liquid held in the transfer section having a capillary structure is boiled by heating, and the recording liquid in the capillary structure is heated. Preferably, one or two or more bubbles having a diameter of 20 μm or less are formed, and the recording liquid in the capillary structure is discharged as particles having a diameter of 10 μm or less by the pressure due to the expansion of the bubbles.

In this case, the surface of the transfer portion is coated with gold, polyimide or nickel plating, and the difference in the contact angle between the transfer portion and the thermally degraded product at 25 ° C. with the recording liquid is 10 ° or less ( (Preferably 5 ° or less).

In the above-described first recording method and recording apparatus of the present invention, and in the second recording method and recording apparatus of the present invention, the transfer section holds the recording liquid by capillary action. It is desirable to provide a structure.

In this case, it is preferable that the recording liquid holding structure is a minute columnar structure, and this is configured as the recording liquid holding means.

Further, it is desirable to provide a resistance heating means below the transfer section as a heating means for the recording liquid.

Hereinafter, preferred embodiments of the present invention will be described in more detail.

The recording apparatus according to the present embodiment is configured, for example, as shown in FIG. That is, the recording head 1 is roughly composed of a paper feed mechanism and an image recording device, and the recording heads 1 for yellow, magenta, and cyan are arranged to face the platen roller 2 respectively. Then, the photographic paper 8 is fed toward the recording head 1 by the paper feed roller 4, and the photographic paper 8 after recording is discharged by the discharge roller 6.

Each head is supplied with a recording liquid of each color (hereinafter, may be referred to as ink), and is connected to a head drive circuit board or the like via a flexible harness 10. The recording head uses cooling fins and a heater for heating.
During operation, the recording head is always kept in a certain temperature range.

The recording head 1 for each color is, for example, as shown in FIG.
As shown in FIG.
A head chip 11 is adhered on the base plate 12, and transfer portions each having one heater are arranged at equal intervals at 300 dpi at 1216 locations and 10 locations on the left and right sides of the dummy at equal intervals.

The photographic paper 8 is the edge 18 of the heater chip 11.
By fixing the angle between the head chip 11 and the photographic paper 8 appropriately, a gap of 100 μm is maintained between the transfer portion 350 μm behind the edge 18 and the photographic paper. The heater drive signal is connected to each transfer unit via the flexible harness 10 and the driver IC 14. The recording liquid flows from an ink tank (not shown), for example, through an ink passage 16 in the base plate 12 and the cover 13 attached to the head chip 11 and the head chip 11.
And is supplied to each transfer section.

FIG. 1 is an enlarged plan view of the vicinity of a transfer portion on a head chip of the above-described recording apparatus, and FIG. 2 is an II-II of FIG.
FIG. 2 shows a line cross-sectional view and an enlarged view of a part thereof.

These are formed roughly as follows.
That is, as shown in FIG. 2, after a silicon oxide layer 28 is formed as a heat insulating layer on a silicon substrate 27, a polysilicon layer 40 is formed thereon as a resistor. Further, an aluminum film is formed by sputtering as an electrode, and a polysilicon heater 19 and an individual electrode
The aluminum film is etched so as to form the second electrode 2 and the common electrode 23. Then, a silicon oxide layer 42 is formed thereon by a CVD method, and a SiO ₂ layer 44 for forming minute prisms and the like described later is further formed thereon by a CVD method.

In this embodiment, before forming the prisms 21 having a square cross section around the transfer portion 17 and arranged in a lattice shape and made of SiO ₂ by the reactive ion etching (RIE), the SiO _{2 is used.} An amorphous fluororesin (for example, Cytop CTX-800 (manufactured by Asahi Glass Co., Ltd.)) is spin-coated on the layer 44 so that the film thickness after curing becomes a predetermined film thickness, and heat-cured.

Thereafter, the surface is slightly roughened by short-time treatment with argon plasma, and then a resist is spin-coated, and a mask designed so that a liquid repellent surface line 24 is formed at the tip of the transfer portion. Exposure and development. Thereafter, when the SiO ₂ micro prisms 21 are etched by the RIE method, the fluororesin can be simultaneously removed by the RIE method. When the resist is removed after the etching, the S and S on the side and bottom surfaces of the pillar structure on the etched transfer portion are removed.
The iO ₂ surface 20 is exposed, and the other surface can be covered with an ink-repellent surface 24 made of a fluororesin.

Then, in order to form a recording liquid supply path for supplying the recording liquid to the transfer section 17, a dry film 25 is attached to the head chip, the recording liquid flow path is patterned, and then the nickel cover 13 is thermocompressed. .

The fluororesin for the ink-repellent treatment described above may be a Cytop CTX as long as the difference in the contact angle with the recording liquid can be made sufficient to stabilize the meniscus in the vicinity of the transfer portion 17. Any fluororesin that can be formed into a thin film other than -800 can be used.

In the recording head, the number of recording liquid storage sections and the number of dots, and the number of heating means and transfer sections corresponding thereto may vary in various ways. Alternatively, the image may be recorded by paper feeding in the main scanning direction and serial scanning in the sub-scanning direction of the recording head orthogonal to the main scanning direction.

The recording liquid 26 used in the present embodiment is composed of a dye, a solvent, and additives added as necessary, so as to optimize transfer sensitivity, heat stability, image quality, and storage stability. In addition, the selection of materials and the ratio of the composition components are adjusted.

The dye suitable for the present embodiment has an appropriate vaporization rate, sufficient heat resistance, sufficient solubility in a solvent described below, low toxicity to the human body, and sufficient storage stability on photographic paper. Any dye can be used as long as it has the following.

Specifically, disperse dyes, oil-soluble dyes, basic dyes and the like are preferred. Particularly preferred dyes include (for example, JP-A-8-244363, JP-A-8-244).
364, JP-A-8-244366), a dicyanostyryl-based yellow dye, a tricyanostyryl-based magenta dye, an anthraquinone-based magenta dye, and an anthraquinone-based cyan dye.

These dyes are purified by any means such as a sublimation purification method, a recrystallization method, a zone melting method, a column purification method, etc., in order to reduce the evaporation residue and prevent the thermal decomposition product from adhering to the transfer portion. It is desirable to use it afterwards.

The solvent of the recording liquid suitable for the present embodiment has a melting point of less than 50 ° C. and a boiling point of less than 150 ° C., a thermal decomposition temperature higher than the boiling point, a high compatibility with the above-mentioned dye, and a human body. Any compound can be used as long as it has low toxicity and is colorless.

Specifically, phthalic esters such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diheptyl phthalate, dioctyl phthalate, diisodecyl phthalate, dibutyl sebacate, dioctyl sebacate, dioctyl adipate , Diisodecyl adipate, dioctyl azelate, dioctyl tetrahydrophthalate, etc., fatty acid esters such as tricresyl phosphate, trioctyl phosphate, etc., tributyl acetyl citrate, butyl phthalyl butyl glycolate, For example, organic compounds generally referred to as plasticizers for plastics can be used.

In order to adjust the physical properties of the recording liquid, appropriate additives such as a surfactant, a viscosity modifier, and a preservative can be added as needed. However, these additives need to have the same boiling point as the solvent and the dye. Specifically, fluorinated fatty acid esters, silylated fatty acid esters, silicone oil, and the like can be used as the surfactant.
Glycerin, tetraethylene glycol, and the like can be used as the viscosity modifier.

The recording liquid 26 contains the above dye in an amount of 5% by weight or more,
Preferably 10% by weight or more, more preferably 20% by weight
As described above, it is prepared by dissolving in the above-mentioned solvent. At this time, in order to increase the solubility, two or more dyes may be mixed and used. At the same time, two or more solvents may be used in combination. Additives are added as needed.

Ink 26 against thermal degradation of ink 26
Is 10 to 30 ° depending on the type of ink, and the capillary structure of the recording head according to the embodiment is such that the contact angle with ink can be selected from the range of 0 to 40 ° according to the ink used. Good.

For example, after purifying a dye in which the amino group of a dicyanostyryl yellow dye described in JP-A-8-244364 is substituted with an isobutyl group with a column, 1 part of the dye is used as a solvent for sebacic acid as a solvent. 7 parts of dibutyl (dye concentration: 12.5% by weight) are added, and the mixture is stirred by an ultrasonic stirrer until completely dissolved, whereby a yellow ink can be prepared.

Similarly, a tricyanostyryl magenta dye described in JP-A-8-244363, in which the amino group of the magenta dye is substituted with a butyl group, is purified by a column. Dibutyl sebacate to 7
Parts (dye concentration: 12.5% by weight), and stirred with an ultrasonic stirrer until completely dissolved to prepare a magenta ink.

Similarly, after purifying a column in which an amino group of an anthraquinone cyan dye described in JP-A-8-244366 was replaced with an ethylhexyl group, 1 part of the dye was added to sebacic acid. 5 parts of dibutyl (dye concentration: 16.7% by weight) may be added and stirred by an ultrasonic stirrer until completely dissolved to prepare a cyan ink.

The printing paper suitable for this embodiment is PPC
(Plain paper copy) Plain paper such as paper, high-quality paper such as art paper, etc. In order to obtain high quality images with particularly high gradation and density, use resins that disperse disperse dyes or oil-soluble dyes. A special paper prepared by applying polyester, polycarbonate, cellulose acetate, CAB (cellulose acetate butyrate), polyvinyl chloride or the like on a base paper can also be used.

In order to improve the recording liquid absorption speed,
The addition of a porous pigment such as silica or alumina has a large effect. In particular, for high-quality recording, photographic paper having an image receiving layer to which a porous pigment having a size of 0.1 μm or less is added, such as a PET (polyethylene terephthalate) film, because the film base has a glossiness, is required to be smooth. It is excellent in color development, gloss, and recording liquid absorption speed.

In order to improve the storage stability of the obtained image or the like, it is effective to add an additive such as an ultraviolet absorber or a radical quencher into the image receiving layer. It is also effective to laminate a resin film on photographic paper.

When these recording liquids 26 are introduced into the cartridges of the corresponding recording heads, the recording liquids spontaneously pass through the tubes by the capillary force, reach the column structure of the transfer section 17 of the head, and the vicinity of the transfer section. Exposed part 2 of SiO ₂ surface
The meniscus 29 is formed at the boundary of the line 30 formed by the zero and the liquid repellent surface 24. The meniscus thus formed can respond to any vibration without changing.

The printing paper 8 is moved to the printing position by the paper feed roller 4 and is conveyed at a predetermined speed by the guide roller.
When the printing paper comes to a predetermined position of the head of each color, as shown in FIG. 7, for example, a rectangular drive pulse having a duty of 80% is supplied to the heater of the recording head via the driver IC by the number corresponding to the image information. The ink 26 in the transfer unit 17 is periodically heated.

In a state where the duty is 90% or more, the ink 26 is vaporized, in a state where the duty is 80%, the ink 26 is discharged by microbubbles, and in a state where the duty is 60 to 70%, the ink 26 is discharged in a Marangoni flow or the like. The surface tension convection due to the temperature gradient is discharged as a driving force. Therefore, any of vaporization, microbubble, and Marangoni flow may be selected depending on how the drive pulse is applied.

The sum of the pulse application time and the rest time for restoring the ink level is the time for forming one pixel. Heating causes the ink 26 held in the capillary structure of the transfer portion to boil to form bubbles, and then mist from the gaps of the capillary portion of the transfer portion to be ejected as the bubbles burst, and to fly through the gaps to produce photographic paper. Attached to and immediately permeates and develops color. The ink 26 lost by the ejection is immediately filled by the capillary force of the capillary structure of the recording unit.

However, the mechanism of the transfer of the recording liquid in the transfer section is considered to be caused by the following phenomenon (1) or (2) due to the heating of the recording liquid by the heater, or by the main phenomenon. Vaporization of the recording liquid at the molecular level. The recording liquid is ejected by the microbubbles as a mist of 3 to 10 μmφ, for example, about 5 μmφ (the ejection droplet of a known bubble jet is as large as 20 to 30 μmφ). A surface tension gradient occurs in the recording liquid, causing a local flow of the recording liquid (for example, Marangoni flow) in the heating area, and discharging a mist of the recording liquid from the vicinity of the heating unit in the transfer unit. Discharge of recording liquid using instability of recording liquid level as driving force. The recording mode based on these phenomena can be controlled to an appropriate ratio according to the recording conditions (particularly, the above-mentioned duty). For example, printing can be mainly performed.

FIG. 11 shows an example of the principle of discharging the recording liquid by the Marangoni flow.

That is, for example, as shown in FIG.
When the heater 54 provided below the transfer unit 51a is heated in the transfer unit 51a in which the ink 55 whose thickness is defined by the ink holding unit (corresponding to a wall or an uneven structure) 52 is disposed. The heat of the heater 54 is
And the surface tension of the ink 55 in this region (that is, the heating region) decreases.

Then, the ink immediately above the heater 54 is drawn by ink having a relatively high surface tension at the outer peripheral portion (peripheral region) of the heater 54, and the liquid level changes as shown in FIG. An ink traveling wave in the direction (the direction of the arrow in the figure) is generated.

Next, as shown in FIG. 11 (C), when the outward ink traveling wave collides with the ink holding means 52, the velocity component of the ink 55 turns upward, and the ink moves along the ink holding means 52. The liquid surface rises upward, and then, as shown in FIG.
Spouts upwards.

Next, when the heating of the heater 54 is stopped and the ink surface is cooled, and the difference in surface tension between the vicinity of the heater (heating area) and the outside of the heater (peripheral area) becomes small, the meniscus recovery force or the exposed transfer is reduced. As shown in FIG. 11E, an ink traveling wave is generated in the inward direction in the figure due to the capillary force on the surface of the unit. When the inward ink traveling waves collide with each other, for example, at the center of the heater as shown in FIG. 11F, a part of the ink is ejected upward as a mist 56 as shown in FIG. 11G. By repeating this operation periodically, ink mist is continuously ejected. In this case, the bottom surface 53 of the transfer section 11a is not exposed.

FIG. 12 shows that the above-mentioned phenomena are mixed or selected from the transfer unit depending on the driving conditions of the heater 19 connected to the individual electrode 22 and the common electrode 23 shown in FIGS. And the state in which the recording liquid is transferred. That is, as shown in FIG. 12, for example, when the duty of the signal pulse applied to the heater is about 40 to 80%, the recording liquid is vaporized simultaneously with the vaporized material 66 and the small mist 65 and has a diameter of 2 mm.
It flies as a large mist 64 of μm or more, and adheres to a not-shown opposing transferred body.

As shown in FIG. 13, when the signal pulse has a duty of about 80 to 90%, the recording liquid flies as a vapor 66 (including a small mist having a diameter of about 1 μm in some cases). Adhere to the transfer-receiving member disposed opposite to the transfer member.

As described above, the duty and the like of the signal pulse applied to the heating means can be appropriately set, and the transfer portion is selectively heated according to information such as an image to be transferred.
The recording liquid corresponding to the heating amount is discharged mainly as a mist of 1 picoliter or less, and the recording liquid can be transferred as a unit pixel to an opposing photographic paper or the like.

However, as shown in FIG. 2, in the conventional head, as described above, the meniscus 29 of the recording liquid formed in the transfer portion is easily changed due to disturbance, for example, as shown by a broken line. The thermal energy required to discharge the ink varies. Also, as shown in FIG. 3, the thermal degradation of the recording liquid 48 adheres to the surface of the transfer unit, and the contact angle of the surface of the transfer unit with the recording liquid changes. The transfer density of the recording liquid changes with time due to a change in meniscus.

Therefore, the present invention has been developed to solve this problem.
It is characterized in that it defines the absolute value of the difference between the contact angle between the transfer section and the liquid repellent treated surface with respect to the recording liquid, and the difference between the contact angle between the transfer section and the thermally degraded substance attached to the surface of the transfer section with the recording liquid. .

[0070]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below, but it goes without saying that the present invention is not limited to the following embodiments.

Example 1 A recording apparatus was manufactured according to the above-described preferred embodiment of the present invention. The head chip is manufactured by using a semiconductor lithography process based on a 625 μm thick 6-inch silicon substrate. 14 to 28 are cross-sectional views of the head chip, showing the manufacturing steps.

FIG. 14 shows the first step, in which a silicon wafer having good heat radiation characteristics (high thermal conductivity) is used for the substrate 27, on which a thermal oxidation method or a CVD (chemical vapor deposition) method is applied. For example, the SiO ₂ layer 28 having a thickness of about 1 to ₂ μm is formed. Since the SiO ₂ layer 28 functions as a heat storage layer immediately below a heater to be described later, the thickness of the SiO ₂ layer 28 needs to consider the heat radiation characteristics of a base aluminum heat sink.

Next, as shown in FIG. 15, a polysilicon layer 40 serving as a resistor (heating element) is formed on the SiO ₂ layer 28 to a thickness of about 150 nm by a low pressure CVD method or the like. The polysilicon layer 40 is formed by doping phosphorus so that the sheet resistance becomes about 4 kΩ.

Then, as shown in FIG. 16, a first layer of aluminum 41 as an electrode slightly doped with titanium is formed on the polysilicon layer 40 by sputtering to a thickness of 400 nm.
The film is formed to a thickness of about nm.

Next, as shown in FIG.
In order to expose the portion of the polysilicon layer 40 where (20 μm × 20 μm) is to be formed as the heater 19, a photoresist is formed in a predetermined pattern, and the aluminum 41 in that portion is selectively removed by etching. In this case, the etching solution is phosphoric acid: nitric acid: acetic acid: water =
A mixed acid mixed in a ratio of 4: 1: 4: 1 is used.

Next, a wiring pattern is formed by etching so as to be electrically connected to each heater section 19. That is, using a photoresist as a mask, aluminum is etched into a conductive pattern with the above-mentioned etching solution.

Next, the polysilicon layer 40 remaining without being etched by the above-mentioned etching solution is subjected to a carbon fluoride gas (C
F ₄ ), the polysilicon layer 40 is changed to an aluminum layer 41 by RIE (reactive ion etching).
Is etched in the same pattern as described above.

At this time, the polysilicon layer 4 of the heater section 19
Since there is a photoresist on 0, the polysilicon layer 40 in this portion is not etched. As a result, the polysilicon layer 40 is processed as a conductor pattern in the same shape as the aluminum layer 41 except for the heater portion exposed in the step of FIG. 17, and the aluminum and the polysilicon are brought into ohmic contact by a heat treatment performed in a later step. And functions as a conductor. The portion 19 where the polysilicon is exposed becomes a high-resistance resistor and functions as a resistance heater. As a result, the first aluminum layer 41 becomes the individual electrodes 22 and the common electrode 23 as shown in FIG.

Next, as shown in FIG. 18, an SiO ₂ layer 42 is formed to a thickness of about 0.5 μm on the entire surface of the conductor pattern and the heater section formed as described above by the CVD method.

Next, as shown in FIG. 19, a photoresist is formed in a predetermined pattern, and the photoresist is
The SiO ₂ layer 42 is etched by the method E to form a through hole 46 for electrically connecting the first-layer aluminum wiring and a second-layer aluminum wiring formed in a step described later.

Then, as shown in FIG. 20, in the state shown in FIG. 19, aluminum is formed to a thickness of about 1.0 μm by sputtering or the like, a photoresist is formed in a predetermined pattern, and using this as a mask, an etching solution is used. Etch aluminum. The second-layer aluminum wiring 43 thus formed has a pattern covering a wide area except for the heater section 19 and the electrode take-out section (not shown) so that the resistance value of the common electrode 23 is made as low as possible. It is.

Next, the SiO ₂ layer as a protective film was
After forming a film to a thickness of about 0.5 μm by the D method,
C. for 30 minutes in a nitrogen atmosphere, and a polysilicon (40 above) and an aluminum electrode (22, 2 above)
After ohmic contact with 3) has sintering process As can, as shown in FIG. 21, the SiO ₂ layer 44 C
A film is formed to a thickness of 7 μm by the VD method.

[0083] Then, as shown in FIG. 22, the fluororesin layer 45 (trade name for liquid-repellent treatment on the SiO ₂ layer 44:
Cytop CTX-800 (fluorine content is 60-70
Wt%), manufactured by Asahi Glass Co., Ltd.)
And then heat-cured at 200 ° C. for 1 hour. Thereafter, the surface is slightly roughened by short-time treatment with argon plasma, and then a resist 47 is spin-coated as shown in FIG.

Next, as shown in FIG. 24, exposure and development are performed using a mask having a predetermined pattern in order to form a small column, a dye container, and an ink dam.

As a result, as shown in FIG. 25, the resist 47 formed in a predetermined pattern is
Performed in _two layers 44 RIE (reactive ion etching), to form a recording material containing portion 32 and the trabecular body 21 group and the ink dam 31 in the SiO ₂ layer 44. This pillar 21
Is a square pillar made of SiO ₂ having a square cross section with a side of 3 μm, a height of 6 μm, and a center-to-center distance of 6 μm, which are arranged in a lattice, and are formed on one heater. In addition, the small column body 21 is schematically illustrated.

When the SiO ₂ micro prisms are etched by the RIE method, unnecessary portions of the fluororesin are simultaneously removed. When the resist 47 is removed after the etching, the SiO 2 on the side and bottom surfaces of the pillar structure on the etched transfer portion is removed.
_{The two} surfaces 20 are exposed, and the other surfaces (the upper surface of the ink weir and the small column) are covered with a liquid-repellent surface 24 made of a fluororesin.

Next, as shown in FIG. 26, bonding pads 35 for taking out individual electrodes and taking out common electrodes are formed.
Is formed in a predetermined pattern for opening the openings, and SiO ₂ is etched by RIE to form individual electrodes 22.
Then, the common electrode 23 is exposed as a bonding pad. In FIG. 26, the opening of the common electrode is not shown.

Next, as shown in FIG. 27, a dry film (sheet resist) 25 having a thickness of about 50 μm is attached, and the ink flow path is patterned.

Next, as shown in FIG. 28, a horizontally long nickel sheet having a thickness of about 20 μm is orthogonally placed on the dry film 25 as a cover 13 and is heated at a temperature of 150 to 180 ° C. to a pressure of 4 to 6 kg / cm ² . Pressure bonding is performed for about 5 minutes under pressure.

As described above, the heaters 19 for heating the recording liquid, the respective wiring conductors including the individual electrodes 22 and the common electrodes 23, the groups of the small columns 21 and the like are formed on the substrate 27, And the manufacturing process is completed.

FIG. 1 is an enlarged plan view of the vicinity of the transfer portion of the head chip manufactured as described above, and FIG.
FIG. 29 is a sectional view taken along line II, and is a detailed view of a part of FIG. 28.

As shown in FIG. 5, a printer 15 comprising a paper feed mechanism and an image recording device was produced by incorporating a recording head using the head chip produced as described above. Each of the recording heads 1 for yellow, magenta, and cyan has a diameter of 1 having a surface layer of silicon rubber.
It is arranged to face the platen roller 2 of 6 mm.
The photographic paper 8 in the paper tray 7 is fed toward the recording head 1 by a feed roller 4 and a guide roller 5 that support the photographic paper 8 so as to sandwich the photographic paper 8. The photographic paper 8 after recording is discharged by the discharge roller 6.

Each recording head 1 has an ink tank 9 of each color.
Supplies the ink 26. The recording head 1 is connected to a head drive circuit board (not shown) and the like via a flexible harness 10. During operation, the recording head 1 is always kept in a constant temperature range by the cooling fins 3 on the back side of the recording head 1 and a heating heater (not shown).

FIG. 6 is a perspective view of the recording head 1 alone. The head chip 11 is placed on the base plate 12.
Is glued. 300dp at the tip of the head chip
The transfer units 17 each having one heater at intervals of i
Six dummies and ten dummies on each side are arranged at equal intervals.

The photographic paper 8 is the edge 18 of the head chip 11.
By fixing the angle between the head chip 11 and the printing paper 8 appropriately, a gap of 100 μm is maintained between the transfer portion located 350 μm behind the edge 18 and the printing paper 8. The heater drive signal is connected to each transfer unit via the flexible harness 10 and the driver IC 14. The ink 26 is supplied from an ink tank 9 (not shown) through the ink passage 16 in the base play 12, to a gap between the cover 13 attached to the head chip and the head chip 11, to each transfer unit.

The ink 26 is composed of a dye, a solvent, and additives to be added as needed. The selection of materials and the ratio of composition components are optimized so as to optimize transfer sensitivity, heat stability, image quality, and storage stability. Formulated.

The dye had a suitable vaporization rate, sufficient heat resistance, sufficient solubility in a solvent, low toxicity to the human body, and sufficient storage stability on photographic paper.

The solvent of the ink 26 has a melting point of less than 50 ° C.
A colorless solvent having a boiling point in the range of 150 ° C. or more and less than 500 ° C., a thermal decomposition temperature higher than the boiling point, high compatibility with the dye, and low toxicity to the human body was used.

As a yellow ink, a dye in which the amino group of a dicyanostyryl-based yellow dye was substituted with an isobutyl group was purified by a column, and then 7 parts of dibutyl sebacate (dye concentration: :
12.5% by weight) and stirred with an ultrasonic stirrer until completely dissolved.

As the magenta ink, a dye in which the amino group of a tricyanostyryl-based magenta dye was substituted with a butyl group was purified by a column, and then 7 parts of dibutyl sebacate (dye concentration: 12. 5% by weight) and stirred with an ultrasonic stirrer until completely dissolved.

As the cyan ink, after purifying a dye in which an amino group of an anthraquinone cyan dye was replaced with an ethylhexyl group by a column, 5 parts of dibutyl sebacate (dye concentration: 16.7% by weight) was used for 1 part of the dye. %) And stirred with an ultrasonic stirrer until completely dissolved.

Peach-coated paper (manufactured by Nisshinbo Co., Ltd.) having a porous structure of several μm on the surface and using the above-mentioned oil-soluble dye and a binder resin compatible with the solvent was used as the printing paper.

As shown in FIG. 2, when these inks 26 are introduced into the corresponding cartridges 9 of the recording heads 1 (see FIG. 5), the inks 26 spontaneously pass through the tubes by capillary force, and The meniscus 29 was formed at the boundary of the line 30 formed by the SiO ₂ surface exposed portion 20 and the lyophobic surface 24 near the ejection portion after reaching the column structure of the transfer portion of the head 1. The thickness of the ink liquid surface at the center of the heater 19 is 7 μm, and the thickness of the ink at the heads of the columns is 1 μm.
Met. The meniscus thus formed did not change under any vibration.

[0104] Incidentally, the second ink 26 of the dibutyl sebacate for transferring portion surface made of SiO ₂ and a solvent
The contact angle at 5 ° C. was 32 °, the contact angle of the ink 26 with the lyophobic surface 24 at 25 ° C. was 75 °, and the difference between the contact angles was 43 °.

The printing paper 8 is moved to the printing position by the paper feed roller 4 and is driven by the guide roller 5 at 1.417 cm / sec.
c. Transported at a speed of When the printing paper 8 comes to a predetermined position of the head of each color, the heater 19 of the recording head 1 is turned on.
Up to 255 times the drive pulse of a rectangular 50KH _Z 80% duty shown in FIG. 7, provided through as many driver IC in accordance with image information, periodically heating the ink of the transfer portion. The pulse application time (255 × 20 μsec =
5.1Msec) and the ink surface time for forming one pixel by adding the rest time 0.9msec for restoring (the period) is 6 msec (167 h _Z).

By heating, the ink 26 held in the capillary structure of the transfer portion boils to form a bubble having a diameter of 12 μm. With the subsequent bursting of the bubble, an average of 0.09 picoliter from the gap of the capillary structure of the transfer portion is removed. Mist and spout, 100μm
Flies through the gap and adheres to the photographic paper 8 and immediately penetrates
It developed color. The ink 26 lost by the discharge was immediately filled by the capillary force of the capillary structure of the transfer portion.

FIG. 8 shows the relationship between the number of gradations (the number of pulses in one pixel) and the reflection density of this embodiment measured by a Macbeth densitometer. Thus, it can be estimated that 64 or more gradations can be expressed in one pixel. That is, the evaporation amount of the ink 26 and the ejection amount of the fine ink mist can be accurately controlled by the number of drive pulses.

In order to print 11 cm, which is the length of the A6 size printing area in the vertical direction, 1.417 cm / sec.
, The time required for the printing operation is 9.2 seconds, the paper feed time (2.2 seconds) and the image transfer time (3. 2 seconds), the printing time of A6 size becomes 14.6 seconds.

The average power required to achieve the maximum density of each color (reflection density = 2) was 0.31 mJ / dot. Since the height of the meniscus was stable, the density unevenness between the dots of the print head was within 1%. In addition, although the above recording operation was performed for 5,000 sheets in A6 conversion, the ink meniscus on the head chip was kept in the initial state.

According to the present embodiment, as shown in FIG. 2, the liquid repellent surface 24 is formed of fluororesin on the upper surface of the ink dam 31, so that the liquid repellent surface 24 comes into contact with the ink 26 at 25 ° C. Since the angle is 43 ° larger than the contact angle of the surface of the transfer portion that is always in contact with the ink 26, the ink 26
The ink does not flow out of the ink container 32 beyond the boundary between the ink 4 and the ink 26. As a result, the ink 26 is stably held in the transfer portion, and the recording at a stable and good transfer density can be performed with low energy without increasing the thickness of the ink layer on the transfer portion.

Embodiment 2 In this embodiment, a similar effect is obtained by selectively coating diamond-like carbon on the same surface instead of the selective liquid repellent treatment using a fluororesin.

That is, the structure of the printer, the structure of the head, the manufacturing process of the head chip, the adjustment of the ink 26, and the printing paper are the same as those in the first embodiment. The diamond-like carbon film was formed by a lift-off technique so as to define a meniscus shape without performing the film formation and etching processes of (Top).

More specifically, as shown in FIG.
_On the wafer 27 after the formation of the fine structure made of _No.2 , a resist 50 is filled in a region excluding the upper surfaces of the small pillars 21 and the ink dam 31, and as shown in FIG. 30, a diamond-like carbon having a thickness of 5 nm is formed thereon. The film 34 was formed. Thereafter, when the resist 50 is removed as shown in FIG. 31, only the diamond-like carbon film 34 on the resist 50 is removed, and the SiO ₂ surface 20 is exposed. The contact angle of the ink 26 using dibutyl sebacate as a solvent at 25 ° C. to the etched SiO ₂ surface 20 was 32 °, and the contact angle of the ink to the diamond-like carbon film 34 at 25 ° C. was 62 °. Angle difference is 3
0 °.

When ink is introduced into the cartridge of the recording head incorporating this head chip, the ink 26 spontaneously reaches the transfer portion 17 by capillary force, and the SiO ₂ surface 20 and the diamond-like carbon film 3 near the transfer portion 17.
4, a meniscus was formed with the boundary 30 formed therebetween. The thickness of the ink 26 liquid surface at the center of the heater 19 is 8 μm, and the thickness of the ink 26 from the head of the column is 2 μm.
μm. The meniscus thus formed did not change under any vibration.

The average power required to achieve the maximum density of each color (reflection density = 2) was 0.35 mJ / dot. Since the height of the meniscus was stable, the density unevenness between the dots of the recording head was within 1%. In addition, this printing operation was performed for 5,000 sheets in A6 format, but the ink meniscus on the head chip was kept in the initial state.

According to the present embodiment, the diamond-like carbon 34 instead of the liquid-repellent material (fluororesin) in the first embodiment has a contact angle with the ink 26 larger by 30 ° than the SiO ₂ surface 20. Therefore, the same effect as that of the first embodiment can be obtained.

Embodiment 3 In this embodiment, the same effects as those of the above-described Embodiments 1 and 2 were obtained by selective eutectoid plating of nickel and Teflon fine particles.

Although the configuration of the printer, the configuration of the head, the manufacturing process of the head chip, the adjustment of the ink 26, and the printing paper are the same as those in the first embodiment, the fluororesin (Cytop) in the first embodiment is used in the manufacturing process of the head chip. Was not performed, and a nickel film containing fine particles of Teflon was formed by a method of eutectoid plating so as to define a meniscus shape. A description will be given with reference to the drawings of the first embodiment (FIGS. 25 to 28) (the same applies to the following examples).

More specifically, as shown in FIG.
_A resist is spin-coated on the wafer 27 after the formation of the fine structure made of ₂ so as to form a meniscus shape,
Exposure and development are performed, and a nickel film is formed by sputtering. Using this nickel film as an electrode, a nickel film containing Teflon fine particles having a thickness of 0.2 μm is formed. Thereafter, when the resist is removed, the SiO ₂ surface of the transfer portion is exposed. The contact angle at 25 ° C. of the ink 26 using dibutyl sebacate as a solvent was 32 ° with respect to the etched SiO ₂ surface, and the contact angle of the ink at 25 ° C. with respect to the eutectoid plating surface was 52 °. The difference was 20 °.

When ink is introduced into the cartridge of the recording head incorporating this head chip, the ink 26 reaches the transfer portion spontaneously due to capillary force, and the Si near the transfer portion.
A meniscus was formed across a boundary formed by the O ₂ surface and the eutectoid plating surface. The thickness of the ink liquid surface at the center of the heater was 8 μm, and the thickness of the ink from the column head was 2 μm. The meniscus thus formed did not change under any vibration.

The average power required to achieve the maximum density of each color (reflection density = 2) was 0.37 mJ / dot. Since the height of the meniscus was stable, the density unevenness between the dots of the print head was within 1%. In addition, the printing operation was performed 5000 sheets in A6 format, but the ink meniscus on the heater chip was kept in the initial state.

According to the present embodiment, the selective eutectoid plating of nickel and Teflon fine particles instead of the material (fluororesin) for the liquid repellent treatment in the first embodiment is more effective for the ink 26 than the surface of the transfer portion. Since the contact angle is larger by 20 °, the same effect as in the first and second embodiments can be obtained.

Embodiment 4 As described above, the thermal degradation product 48 of the ink 26 is shown on the surface of the transfer portion in FIG. 3 (a) (the structure of FIG. 2 is partially simplified:
The same applies to the following), and the thermal deterioration causes the wettability to increase, causing a local meniscus change to fluctuate the ink transfer density over time.

The initial contact angle of the ink 26 using dibutyl sebacate as a solvent with respect to the capillary structure at the transfer portion of the recording head is 32 ° for each color at 25 ° C. The capillary structure of the part
The thermally degraded product 48 of the ink 26 is thinly attached, and the contact angle of the ink 26 with the thermally degraded product 48 becomes 11 ° at 25 ° C. for each color. 2 for the ink 26 of gold
The contact angle at 5 ° C. was 10 °, and as shown in FIG. 3B, gold 49 was coated on the small column 21 of the transfer portion as a material having a contact angle close to the thermally degraded product of the ink 26.

The printer configuration, the head configuration, the head chip manufacturing process, the adjustment of the ink 26, and the printing paper are the same as in the first embodiment, but in the head chip manufacturing process, the fluororesin (Cytop) in the first embodiment is used. The gold film 49 was formed only on the transfer portion by the lift-off method without performing the film formation and etching process of the above.

More specifically, as shown in FIG.
After covering the entire surface of the wafer after the formation of the fine structure made of ₂ with the resist, and removing the resist after depositing gold by a sputtering method to a thickness of 0.1 μm, the gold film on the resist is removed, As shown in FIG. 3B, only the transfer portion is covered with the gold layer 49.

When the ink was introduced into the cartridge of the recording head incorporating the head chip, the ink spontaneously reached the transfer portion by capillary force to form a meniscus. The contact angle of the ink 26 with the capillary structure of the transfer portion on the head chip after the printing operation of 5,000 sheets in A6 conversion hardly changes from the initial contact angle even if the thermally deteriorated ink adheres, and the recording sensitivity varies. Was within 3%.

According to this embodiment, the gold 4 having a contact angle close to the contact angle of the thermally degraded product at 25 ° C. with the ink 26 is obtained.
9, since the contact angle with both inks 26 hardly changes even if the thermally degraded material 48 adheres to the coated gold film, a local meniscus change of the ink around the transfer portion is obtained. No change occurs in the recording sensitivity, and there is almost no change in the recording sensitivity over time.

Embodiment 5 In this embodiment, the same effect as in Embodiment 4 is obtained by coating photosensitive polyimide as a material having a contact angle close to that of the thermally degraded ink 26 on the capillary structure of the transfer portion. .

The printer configuration, the head configuration, the head chip manufacturing process, the adjustment of the ink 26, and the printing paper are the same as those in the first embodiment. However, in the head chip manufacturing process, the fluororesin (Cytop) in the first embodiment is used. The photosensitive polyimide film was formed only on the transfer portion including the pillar structure without performing the film forming and etching processes of the above.

More specifically, as shown in FIG.
_A photosensitive polyimide of 0.2 μm was applied to the wafer after the formation of the fine structure made of No. _2, and unnecessary polyimide was removed by exposure and development using a mask that left only the transfer portion.
The contact angle at 25 ° C. with ink 26 using photosensitive polyimide dibutyl sebacate as a solvent was 16 °.

When the ink was introduced into the cartridge of the recording head incorporating this head chip, the ink 26 spontaneously reached the transfer portion by capillary force to form a meniscus. The contact angle of the ink 26 with respect to the capillary structure of the transfer portion on the head chip after the printing operation of 5,000 sheets in A6 conversion hardly changes from the initial contact angle even if the thermally degraded substance of the ink 26 adheres, and the recording sensitivity is reduced. The variation was within 4%.

According to this embodiment, the ink 26 at 25 ° C.
Since the transfer portion is covered with polyimide having a contact angle close to the contact angle of the thermally degraded product with respect to the above, the same effect as in the fourth embodiment described above can be obtained.

Embodiment 6 In this embodiment, the same effect as in Embodiment 4 was obtained by plating the capillary structure of the transfer portion with nickel having a contact angle close to that of the thermally degraded ink 26.

Although the structure of the printer, the structure of the head, the manufacturing process of the head chip, the adjustment of the ink 26, and the printing paper are the same as those in the first embodiment, the fluororesin (Cytop) in the first embodiment is used in the manufacturing process of the head chip. Was not performed, and nickel was plated only on the transfer portion including the pillar structure.

More specifically, as shown in FIG.
_The entire surface excluding the transfer portion of the wafer after the formation of the fine structure of the _second product was covered with a resist, and a nickel layer of 0.5 μm was coated by an electroless plating method. The contact angle of the electroless plated nickel surface at 25 ° C. with the ink 26 using dibutyl sebacate as a solvent was 16 °.

When the ink was introduced into the cartridge of the recording head incorporating the head chip, the ink 26 spontaneously reached the transfer portion by capillary force to form a meniscus. The contact angle of the ink 26 with respect to the capillary structure of the transfer portion on the head chip after the printing operation of 5,000 sheets in A6 conversion hardly changes from the initial contact angle even if the thermally degraded substance of the ink 26 adheres, and the recording sensitivity is reduced. The variation was within 5%.

According to this embodiment, the ink 26 at 25 ° C.
Since the transfer portion is covered with nickel plating having a contact angle close to the contact angle of the thermally degraded material with respect to the transfer portion, the same effect as that of the fourth embodiment can be obtained.

Comparative Example 1 Examples 4 to 6 were performed except that the liquid repellent treatment for stabilizing the ink meniscus near the transfer portion was not performed as in Examples 1 to 3. A print head was manufactured in the same process as in Example 1 except that the process for reducing the change in the wettability of the ink 26 in the transfer portion due to the thermal degradation of the ink 26 was not performed.

When ink using dibutyl sebacate as a solvent was introduced into the cartridge of the recording head incorporating the head chip, the ink 26 spontaneously reached the transfer portion by capillary force and formed a meniscus near the transfer portion. ,
Since there was no lyophobic treatment, both the contact angle of the transfer portion with the ink and the contact angle of the non-contact portion with the ink 26 became 32 °, and the tip of the meniscus fluctuated easily. As a result, the thickness of the ink liquid surface at the center of the heater had a distribution of 15 to 20 μm, and the thickness of the ink liquid surface was easily changed by vibration.

The average power required to achieve the maximum ink density (reflection density = 2) of each color reaches 1.07 mJ / dot because the meniscus is too high, and the average height of the meniscus is not stable. The density unevenness between dots of the recording head became 10% or more. The contact angle of the ink to the transfer portion, which was initially 32 °, was 5000 in A6 conversion.
After the sheet recording operation, the temperature decreased to 11 °, the refill speed of the ink 26 fluctuated greatly, and the fluctuation of the recording sensitivity reached 25% or more.

Comparative Example 2 In this example, a silicone resin was used for a liquid repellent treatment for stabilizing a meniscus.

Although the structure of the printer, the structure of the head, the manufacturing process of the head chip, the adjustment of the ink 26, and the printing paper are the same as those in the first embodiment, the fluororesin (Cytop) in the first embodiment is used in the manufacturing process of the head chip. Was not performed, and a silicone resin film was formed in a shape defining a meniscus shape by a lift-off technique.

More specifically, as shown in FIG.
After spin-coating the resist to form a meniscus shape on the wafer after the formation of the fine structure made of ₂ , exposure,
After development, a methyl silicone resin (Dow Silicone, SR2411 manufactured by Toray Industries, Inc., SR2411) was applied and the resist was removed after heat curing, the SiO ₂ surface was exposed at the transfer portion, and the upper surface of the ink dam at the tip was covered with the silicone resin. . The contact angle of the ink with the silicone resin surface was 47 °.

When the ink 26 using dibutyl sebacate as a solvent is introduced into the cartridge of the recording head incorporating the head chip, the ink spontaneously reaches the transfer portion by capillary force, and the SiO ₂ surface near the transfer portion and the silicone A meniscus was formed across the boundary formed by the resin film. Since the liquid repellency of the silicone resin was weak, the thickness of the ink surface at the center of the heater had a distribution of 11 to 12 μm, and the thickness of the ink surface changed due to vibration.

The average power required to achieve the maximum density of each color ink (reflection density = 2) reaches 0.62 mJ / dot because the meniscus is high, and because the height of the meniscus is not stable, The density unevenness between the dots of the recording head became 5% or more.

Comparative Example 3 In this example, the transfer section was treated with a silane coupling agent in order to alleviate the change in the wettability of the ink in the transfer section due to the thermal degradation of the ink 26.

Although the structure of the printer, the structure of the head, the manufacturing process of the head chip, the adjustment of the ink 26, and the printing paper are the same as those in the first embodiment, the fluororesin (Cystop) in the first embodiment is used in the manufacturing process of the head chip. The silane coupling agent was coated only on the transfer portion including the pillar structure without performing the film forming and etching processes of the above.

More specifically, as shown in FIG.
_The entire surface excluding the transfer part of the wafer after the formation of the fine structure made of ₂ is covered with a resist, a silane coupling agent (manufactured by Tokyo Ohka Co., Ltd., HMDS (hexamethyldisilazane)) is treated, and a heat treatment is performed after the resist is removed. H
The contact angle of MDS treated surface to ink at 25 ° C is 26 °
Met.

When the ink 26 using dibutyl sebacate as a solvent was introduced into the cartridge of the recording head incorporating this head chip, the ink spontaneously reached the transfer portion by capillary force to form a meniscus. 500 in A6 conversion
After the zero-sheet printing operation, the contact angle of the ink to the capillary structure of the transfer portion on the heater chip is reduced from 26 ° at the initial stage to 11 °, the refill speed of the ink 26 fluctuates, and the fluctuation of the recording sensitivity becomes 10%. Reached.

The data of each of the above Examples and Comparative Examples are summarized in Tables 1 and 2 below.

[0152]

As shown in Table 1 above, in Examples 1 to 3 in which the liquid-repellent treatment was performed on the surface that did not come into contact with the ink, the respective inks were compared with Comparative Examples 1 and 2 in which the liquid-repellent treatment was not performed. And the thickness of the ink on the transfer portion (on the small column) is 2 μm or less, and the thickness of the ink is moderate compared to the case of the comparatively thick comparative example. It can be seen that the initial meniscus is formed as follows. As a result, it was proved that the energy required for ejecting the ink was small and the density unevenness was small.

As shown in Table 2 above, Examples 4 to 6 in which a material having a contact angle close to the contact angle of the thermally degraded ink with ink was used and the surface of the transfer portion was covered, The absolute value of the difference between the contact angle of the transfer portion surface with the ink and the contact angle of the degraded product with the ink is smaller than in the case of Comparative Examples 1 and 3, which are not covered with. Therefore, even if the deteriorated material adheres, the initial contact angle hardly changes (that is, the meniscus position can be stabilized with time).
It was proved that the fluctuation of the recording sensitivity after recording 5,000 sheets was very small as compared with Comparative Examples 1 and 3.

FIG. 9 is a graph showing the data of Table 1 above, and FIG. 10 is a graph showing the data of Table 2 above.

The embodiments described above can be variously modified based on the technical concept of the present invention.

For example, if a sufficient difference in contact angle with ink for stabilizing the meniscus in the vicinity of the transfer portion can be obtained, any fluororesin other than CYTOP CTX-800 that can be thinned can be used. .

As the material having a contact angle close to the contact angle of the thermally degraded product with the ink, a material having the same contact angle with the ink as that of the embodiment other than the material used in the above-described embodiment is used. can do.

Further, the number of ink storage units and the number of dots, and the number of heating means and transfer units corresponding to the number of ink storage units may be variously changed. Printing can also be performed by paper feeding in the main scanning direction and serial scanning in the sub-scanning direction of the recording head orthogonal to the main scanning direction.

Further, dyes, solvents, additives and the like of the ink may be appropriately prepared in addition to the examples, and photographic papers other than those used in the examples may be used.

Instead of a small columnar body having a square cross section formed on the head chip, a small columnar body may be formed having a circular or rectangular cross section and a polygon other than a square. Furthermore,
As a heating means, a known heating method (for example, laser or the like) other than the embodiment can be used.

Further, in the above-described embodiment, the liquid repellent treatment of the non-contact surface with respect to the ink using the fluororesin (DLC or eutectoid plating) and the contact angle close to the contact angle with the ink of the thermally degraded product are provided. The same head chip can be used for both the coating of the transfer portion surface with the material.

In the above-described embodiment, the fluororesin is provided on the ink weir and the small column, but may be provided on the ink weir and a part of the small column (only the transfer portion). As shown in (2), the fluorine resin 45 may be provided only on the ink dam.

[0164]

As described above, according to the first recording method and the recording apparatus of the present invention, the recording liquid in contact with and held by the transfer section is discharged or vaporized, and the transfer target arranged opposite to the transfer section is transferred. When transferring to the body, the contact angle between the outer region of the transfer section and the recording liquid at 25 ° C. is set to be larger than the contact angle between the transfer section and the recording liquid at 25 ° C. by 20 ° or more. The recording liquid is prevented from flowing out to the outer region of the portion, and the meniscus is formed stably, so that the recording liquid is stably held at a predetermined thickness in the transfer portion, and as a result, stable and good transfer is achieved even at low energy. This is a density, and recording without density unevenness can be performed.

Further, according to the second recording method and the recording apparatus of the present invention, the recording liquid in contact with and held by the transfer section is discharged or vaporized and is transferred to a transfer object arranged opposite to the transfer section. The absolute value of the difference between the contact angle between the transfer portion and the recording liquid at 25 ° C .; and the contact angle between the thermally degraded material attached to the transfer portion surface during the recording operation and the recording liquid; As described below, even if a substance such as a thermally degraded substance of the recording liquid adheres to the surface of the transfer part during the recording operation, the contact angle of the recording liquid does not change so much. In addition to a small variation in meniscus, there is little change in density over time, and recording can be performed at a stable transfer density.

[Brief description of the drawings]

FIG. 1 is an enlarged plan view showing a part of a head chip according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

3A and 3B are cross-sectional views showing a part of the head chip, wherein FIG. 3A is a state in which a thermally degraded substance is attached to a small column, and FIG.
FIG. 4 is a cross-sectional view showing a state where the surface of the transfer unit is covered with gold.

FIG. 4 is a cross-sectional view of a part of a head chip, showing the same modified example.

FIG. 5 is a schematic perspective view showing a main part of the recording apparatus.

FIG. 6 is a schematic perspective view of the recording head.

FIG. 7 is a diagram showing a drive pulse shape given to a recording head.

FIG. 8 is a density characteristic diagram of a gradation pattern obtained in the embodiment.

FIG. 9 is a diagram illustrating a relationship between a difference in contact angle between the surface of the heater chip before and after the meniscus boundary line with ink and uneven density between dots of the initial print head.

FIG. 10 shows a contact angle of the columnar structure of the transfer unit with ink,
FIG. 7 is a diagram illustrating a relationship between an absolute value of a difference between a contact angle with ink of a thermally degraded ink generated after printing 5,000 sheets in A6 conversion and a change in recording density.

FIG. 11 is a schematic diagram illustrating an example of a transfer principle based on Marangoni flow.

FIG. 12 is a schematic plan view of a main part showing how ink flies.

FIG. 13 is a schematic plan view of a main part showing a state in which ink vaporizes and flies.

FIG. 14 is a schematic sectional view illustrating a manufacturing process of a head chip according to an embodiment of the present invention.

FIG. 15 is a schematic sectional view showing another manufacturing process.

FIG. 16 is a schematic sectional view showing another manufacturing process.

FIG. 17 is a schematic sectional view showing another manufacturing process.

FIG. 18 is a schematic sectional view showing another manufacturing process.

FIG. 19 is a schematic sectional view showing another manufacturing process.

FIG. 20 is a schematic sectional view showing another manufacturing process.

FIG. 21 is a schematic cross-sectional view showing another manufacturing process.

FIG. 22 is a schematic cross-sectional view showing another manufacturing process.

FIG. 23 is a schematic cross-sectional view showing another manufacturing process.

FIG. 24 is a schematic sectional view showing another manufacturing process.

FIG. 25 is a schematic sectional view showing another manufacturing process.

FIG. 26 is a schematic sectional view showing another manufacturing process.

FIG. 27 is a schematic cross-sectional view for explaining another manufacturing process.

FIG. 28 is a schematic cross-sectional view for explaining still another manufacturing process.

FIG. 29 is a schematic cross-sectional view showing another manufacturing process.

FIG. 30 is a schematic sectional view showing another manufacturing process.

FIG. 31 is a schematic sectional view showing still another manufacturing process.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Recording head, 2 ... Platen roller, 3 ... Cooling fin, 4 ... Feed roller, 5 ... Guide roller, 6 ... Discharge roller, 7 ... Paper tray, 8 ... Printing paper, 9 ... Ink tank,
10: Flexible harness, 11: Heater chip, 1
2: Base plate, 13: Cover, 14: Driver I
C, 15 ... printer, 16 ... ink passage, 17 ... transfer unit, 18 ... edge, 19 ... heater, 20 ... SiO ₂ exposed portion, 21 ... trabecular body, 22 ... individual electrodes 23 ... common electrode,
24: liquid repellent surface, 25: dry film, 26: ink (recording liquid), 27: silicon substrate, 28: SiO ₂ , 2
9 ... meniscus, 30 ... border, 31 ... ink weir, 32 ...
Ink storage unit, 34: diamond-like carbon, 4
1, 43: aluminum wiring, 42, 44: SiO ₂ 4
5: Fluororesin, 46: Through hole, 47, 50: Resist, 48: Thermal degradation product, 49: Gold film

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C056 EA06 EA11 ED01 FA03 FD15 FD20 HA05 HA16 HA24 2C065 AA01 AB10 AC01 DZ03 DZ09 2H111 AA01 AA26 AA31 AA43 AB00 HA12 HA24 HA35

Claims (26)

[Claims] When discharging a recording liquid in contact with a transfer section or vaporizing the recording liquid and transferring the recording liquid to an object to be transferred which is disposed opposite to the transfer section, an outer region of the transfer section and the recording liquid are transferred. A recording method wherein the contact angle at 25 ° C. is larger than the contact angle between the transfer portion and the recording liquid at 25 ° C. by 20 ° or more. 2. The transfer-portion outside region is arranged on the side opposite to the recording-liquid supply port to the transfer portion having a capillary structure so as not to come into contact with the recording liquid. The recording method according to claim 1, wherein a meniscus of the recording liquid is defined by a boundary with the recording liquid. 3. One or two or more bubbles having a diameter of 20 μm or less are formed in the recording liquid in the capillary structure by boiling by heating, and the recording liquid in the capillary structure is formed by the pressure due to expansion of the bubbles. The recording method according to claim 2, wherein the recording medium is ejected as particles having a diameter of 10 μm or less. 4. The liquid repellent treatment for the recording liquid according to claim 1, wherein the surface of the transfer portion outside region is coated with a fluororesin, diamond-like carbon, or a mixture of nickel and fluororesin fine particles, and the liquid repellent treatment is performed on the recording liquid. Recording method. 5. The recording method according to claim 1, wherein a recording liquid holding structure that holds the recording liquid by a capillary phenomenon is disposed in the transfer section. 6. The recording method according to claim 5, wherein the recording liquid holding structure is a minute columnar structure, and this is configured as the recording liquid holding means. 7. The recording method according to claim 1, wherein a resistance heating unit is provided below the transfer unit as the recording liquid heating unit. 8. When discharging or vaporizing a recording liquid held in contact with a transfer section and transferring the recording liquid to an object to be transferred disposed opposite to the transfer section, the recording liquid between the transfer section and the recording liquid is discharged.
A recording method in which the absolute value of the difference between the contact angle at 10 ° C. and the contact angle between the thermally degraded material attached to the transfer portion surface and the recording liquid during the recording operation is 10 ° or less. 9. The recording liquid held in the transfer section having a capillary structure is boiled by heating to form one or two or more bubbles having a diameter of 20 μm or less in the recording liquid in the capillary structure. 9. The recording method according to claim 8, wherein the recording liquid in the capillary structure is discharged as particles having a diameter of 10 [mu] m or less by the pressure due to the expansion of the bubbles. 10. The recording method according to claim 8, wherein the surface of the transfer portion is covered with gold, polyimide, or nickel plating to generate the difference in the contact angle. 11. A recording liquid holding structure for holding the recording liquid by a capillary phenomenon at the transfer portion.
The recording method described in. 12. The recording liquid holding structure is a minute columnar structure, which is configured as the recording liquid holding means.
The recording method according to claim 11. 13. The recording method according to claim 8, wherein a resistance heating unit is provided below the transfer unit as the recording liquid heating unit. 14. A recording apparatus configured to discharge or vaporize a recording liquid that is held in contact with a transfer unit and transfer the recording liquid to an object to be transferred disposed opposite to the transfer unit. The transfer unit and the transfer unit outer region are arranged such that a contact angle of the region and the recording liquid at 25 ° C. is larger than a contact angle of the transfer unit and the recording liquid at 25 ° C. by 20 ° or more. A recording device characterized by being formed. 15. The transfer section outside area is arranged on the opposite side of the recording liquid supply port to the transfer section having a capillary structure so as not to come into contact with the recording liquid. 15. The recording apparatus according to claim 14, wherein a meniscus of the recording liquid is defined by a boundary with the recording liquid. 16. One or two or more bubbles having a diameter of 20 μm or less are formed in the recording liquid in the capillary structure by boiling due to heating, and the recording liquid in the capillary structure is formed by pressure due to expansion of the bubbles. The recording apparatus according to claim 15, wherein the recording apparatus is ejected as particles having a diameter of 10 μm or less. 17. The liquid-repellent treatment with respect to the recording liquid, wherein the surface of the transfer portion outside region is coated with a fluororesin, diamond-like carbon, or a mixture of nickel and fluororesin fine particles, and is subjected to a liquid repellent treatment for the recording liquid. The recording device described. 18. The recording apparatus according to claim 14, wherein a recording liquid holding structure that holds the recording liquid by capillary action is provided in the transfer unit. 19. The recording apparatus according to claim 18, wherein the recording liquid holding structure is formed of a fine columnar structure, and this is configured as the recording liquid holding means. 20. The recording liquid heating means, wherein a resistance heating means is provided below the transfer section.
4. The recording device according to 4. 21. A recording apparatus configured to discharge or vaporize a recording liquid in contact with and held by a transfer unit and transfer the recording liquid to a transfer target disposed opposite to the transfer unit. The absolute value of the difference between the contact angle at 25 ° C. with the recording liquid; and the contact angle between the thermally degraded material attached to the surface of the transfer section during the recording operation and the recording liquid must be 10 ° or less. A recording device characterized by the above-mentioned. 22. The recording liquid held in the transfer section having a capillary structure is boiled by heating, and one or more bubbles having a diameter of 20 μm or less are formed in the recording liquid in the capillary structure. 22. The recording apparatus according to claim 21, wherein the recording liquid in the capillary structure is discharged as particles having a diameter of 10 [mu] m or less by the pressure due to the expansion of the bubbles. 23. The recording apparatus according to claim 21, wherein a surface of the transfer portion is coated with gold, polyimide, or nickel plating, and is configured to cause the difference in the contact angle. 24. The recording apparatus according to claim 21, wherein a recording liquid holding structure that holds the recording liquid by capillary action is provided in the transfer unit. 25. The recording apparatus according to claim 24, wherein the recording liquid holding structure is formed of a minute columnar structure, and is configured as the recording liquid holding means. 26. The recording liquid heating means, wherein a resistance heating means is provided below the transfer section.
2. The recording device according to 1.