JPH0334816A - Manufacture of annular film - Google Patents

Abstract

PURPOSE:To manufacture an annular film uniform in thickness by applying solution in a straight and continuous jet to the outer surface of a cylindrical mold without atomizing the solution from a discharge port capable of moving from one end to the other end of the cylind. CONSTITUTION:A cylindrical or pillar-shaped mold 01 for forming an annular film is set on a cylindrical or pillar-shaped mold supporting and rotating shaft 02, and rotated by a rotational motor 03. In a gun 05, an ejection port 12 for applying organic polymer or the solution of precursor thereof is provided, wherein the solution is supplied via a solution extraction pipe 07, and discharged straightly without atomizing from the protruded port 12, and thus a film is formed on the outer peripheral surface of the cylindrical or pillar-shaped mold. As an organic polymer, there being no limitation in particular, noncrystal thermoplastic resin relatively soluble in a flux such as polystyrene, polymethyl methacrylate, polycarbonate or the like is suitable. And, there also being no limitation in particular as to the precursor, thermosetting resin such as polyamic acid or polyamideimide resin, diallylphthalate or silicone resin or the like as being the precursor of the polyimide is suitable therefor.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for manufacturing a seamless annular film that can be applied not only to general conveyor belts but also to conveyor films, transfer films, and fixing films of image forming apparatuses. It is something.

[Conventional technology]

In general, conveyor belts, conveyor films of image forming devices, transfer films, and fixing films usually have no seams.
Moreover, there is a need for an annular film with a smooth inner circumferential surface, or in some cases with a predetermined uneven shape on the inner circumferential surface. When manufacturing a seamless annular film having such an inner circumferential surface shape, a method is usually performed in which the outer circumferential surface of a cylindrical or cylindrical mold is subjected to a necessary shape treatment and a film is formed thereon. That is, a method is used in which a film is formed on the outer peripheral surface of a cylindrical or cylindrical mold, and the shape formed on the outer peripheral surface of the cylindrical mold is transferred to the inner peripheral surface of the film.

Conventionally, a method for forming a film using the outer circumferential surface of a cylindrical or cylindrical mold as described above involves applying a solution of an organic polymer or its precursor to the outer circumferential surface of the cylindrical or cylindrical mold. There is a spray method in which the material is atomized and applied from a discharge port, and another method is to immerse it in a solution of a cylindrical or cylindrical organic polymer or its precursor and gradually pull it up. A dip coating method is known that utilizes the surface tension of a cylindrical mold and an organic polymer or its precursor solution.

Conventionally, after the coating film formed as described above is dried and solidified or the reaction is completed, it is removed from the outer peripheral surface of a cylindrical mold or columnar mold to obtain an annular film.

[Problem that the invention is trying to solve]

However, the conventional spray method has the following problems and drawbacks.

(1) The surface of the coating film tends to become uneven.

(2) Since the solution is atomized by pressure or the like and becomes radial, the efficiency of adhesion of the solution to the mold is low, which is economically disadvantageous.

(3) The surface of the coating becomes rough and air is partially trapped, resulting in a significant drop in physical properties.

Furthermore, the dip coating method has the following problems.

(1) A large amount of solution is required to be used.

(2) It is necessary to adequately control the concentration of the solution.

(3) Since the immersed area is coated, a coating film is formed even on areas that do not require coating, resulting in a large loss of solution (which is economically disadvantageous).

(4) In the case of a solution using a solvent with a slow volatilization rate, it takes time for the solution to dry and solidify, during which time a liquid drip occurs and the coating film becomes uneven. Incidentally, this problem can be solved by attaching it to the rotating device, but the process of attaching it to the rotating device increases, and the work efficiency decreases.

[Purpose of the invention]

The present invention has been made to solve the problems of the above-mentioned conventional example.

[Summary of the invention]

The present invention produces an annular film by applying a solution of an organic polymer or its precursor to the outer surface of a rotating cylindrical or cylindrical mold, and peeling it off from the cylindrical mold after drying and solidification or completion of the reaction. In the method, the annular film is coated by continuously spraying the solution in a streaky manner without substantially atomizing it from a movable discharge port on the outer surface of the cylindrical mold from one end to the other end. Relating to a manufacturing method.

[Detailed description of the invention]

According to the present invention, a solution of an organic polymer or its precursor is applied to the outer surface of a rotating cylindrical or cylindrical mold, and after drying and solidification or completion of the reaction, an annular film is produced. By applying the solution with a beam from a movable discharge port on the outer surface of the cylindrical mold from one end to the other end, it is possible to use the minimum amount of solvent or solution necessary, especially a solvent with a slow volatilization rate. It has become possible to produce an annular film with uniform thickness from organic polymers or precursors.

In the present invention, a solution of a solvent-soluble organic polymer or its precursor is used.

The organic polymer mentioned above is not particularly limited, but includes polystyrene, polymethyl methacrylate, polycarbonate,
Non-grade thermoplastic resins that are relatively easily soluble in solvents, such as polyphenylene ether, polysulfone, polyarylate, polyetherimide, and polyethersulfone, are suitable.

There are no particular restrictions on the precursor, but polyamic acid, polyamideimide resin, polybenzimidazole resin, which is a precursor of polyimide, and thermosetting resins such as epoxy resin, unsaturated polyester, diallyl phthalate, and silicone resin are used. suitable.

Furthermore, there are no particular limitations on the solvent used as long as the organic polymer or its precursor is soluble therein.

The present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram of an apparatus for beam coating used in manufacturing the annular film of the present invention.

Here, 01 is a cylindrical or cylindrical mold for forming an annular film, which is set on a rotating shaft 02 that also holds the cylindrical or cylindrical mold, and is rotated by a rotary motor 03.

05 is a gun provided with a protrusion 12 for applying a solution of an organic polymer or its precursor; the solution is supplied through a solution outlet pipe 07, and the solution is supplied from the protrusion without being substantially atomized. A coating film is formed on the outer peripheral surface of the cylindrical or cylindrical mold.

Incidentally, FIGS. 2 and 3 represent the concept when a coating film is formed.

Here, as a method of supplying the solution, it is possible to supply the solution by using air pressure as shown in 09, for example, but as another method, it is also possible to supply the solution by using a gear pump.

In addition, in the present invention, the rotational speed of the cylindrical mold is 50
RPM or more is effective, but preferably a rotation speed of 50 RPM or more and 300 RPM or less is used.

Further, the material of the cylindrical mold is not particularly limited, and may include Gauss, aluminum, iron, brass, stainless steel, and resin that is not immersed in the solvent used.

Furthermore, in consideration of later peeling, it is also possible to apply a fluorine-based, silicone-based, etc. mold release agent to the outer surface.

Next, there is no particular restriction on the outer diameter of the cylindrical or cylindrical mold, but preferably one having a diameter of 10 mm or more can be used. Further, there is no particular restriction on the length, and there will be no problem as long as it is within a range that can be attached to the device.

The viscosity of the organic polymer or its precursor solution used in the present invention is preferably 0.01 to 500 poise (at room temperature), and preferably 10 poise or less in consideration of the smoothness of the coating surface.

Next, the distance between the discharge port and the inner surface of the cylindrical mold is 2 to 10
0 mm, particularly preferably in the range of 5 to 50 mm.

Hereinafter, the present invention will be explained in more detail with reference to the accompanying drawings.

In the present invention, in order to improve the film-forming properties of the paint film, the paint discharged from the micro-openings is not substantially atomized and is flown in a streaky manner as shown in FIG. This is to increase the proportion of the space volume of the paint to reduce the contact of the paint with air, thereby preventing deterioration of the paint due to volatilization of volatile components in the paint.

The main feature of the present invention is that the proportion of the space occupied by the paint is 100% from the viewpoint of preventing denaturation of the paint, that is, it reaches the object to be coated in streaks without being atomized. Compared to the extremely low proportion of space volume occupied by paint in coating methods such as 0.1 to 0.001%, even when the discharge angle is set to 3 degrees or less, the proportion of space volume occupied by paint is extremely low. It was approximately 95 to 100%, and the volatilization of volatile components in the paint was small, and the paint was not denatured, so substantially the same effect as the gist of the present invention was obtained.

Therefore, in the method of the present invention for forming a coating film by discharging paint from a minute opening, a state in which the paint is not substantially atomized means that the discharge angle is 3 degrees or less, preferably 0 degrees Celsius, and the paint continuously flies in a streak shape. It indicates the condition.

Furthermore, with conventional coating methods, the paint adhesion efficiency was extremely low at 20-50%, resulting in a loss of 50-80% of the paint. Since the paint is concentrated in a minute area, the paint adhesion efficiency is 95% or more, and there is no paint adhesion to areas where no paint film is formed, so the paint does not run around to other areas.

On the other hand, since the paint concentrates in a minute area, the flying energy of the paint increases densely, which tends to roughen the surface of the paint film. ~200 m/sec), the surface of the object to be coated is likely to be affected. In particular, if it is severe, bubbles will be generated in the coating film, resulting in coating defects. Therefore, in order to further improve the surface properties of the paint film, the discharge speed should be 30 m/sec or less, considering the concentration of the paint in a minute area (the paint spreads slightly on the substrate, so it is concentrated in about 1/100 of the area). Preferably, even in the range 25 m/sec to 2 m/sec, especially 10 m/sec to 5 m/sec
A range of is preferred.

By setting the discharge speed to 30 m/see or less, the energy when the paint adheres to the object to be coated is reduced,
The paint completely adheres to the object to be coated without reflection and scattering, and overmist treatment (paint that did not adhere to the object to be coated forms spots, repellents, and (Because it causes loss of gloss, an exhaust system was installed to discharge it out of the system. To prevent pollution, it must be collected using dust collection equipment, etc. at the time of discharge.) In addition to significantly reducing the amount of waste, it also eliminates the need to install a means to prevent paint adhesion. Paint will no longer adhere to the formed part.

In the coating method of the present invention, the distance between the object to be coated and the minute opening is preferably in the range of 2 to 100 mm, particularly 5 to 50 mm. Paints can be widely applied, including those in which solids are dissolved or dispersed in a solvent, and those containing only solids. Furthermore, not only volatile solvents but also nonvolatile solvents can be used. In addition, the viscosity of the paint is 1000 cps, or even 200 cps, since the paint is smoothed by surface tension after adhering to the substrate.
ps or less, particularly preferably in the range of 50 cps to 4 cps.

Further, the discharge port diameter of the minute opening is preferably 200 μm or less, more preferably in the range of 50 μm to 1.80 μm, particularly preferably in the range of 60 μm to 150 μm. The discharge pressure of paint from a minute opening is 3Kg.
f/c g or less is preferable, and more preferably 0. 3Kg
f/crrr ~1.5Kgf/cm, especially 0
．． 5Kgf/ci~IKgf/crr? A range of is preferred. The amount of paint discharged is preferably 20 cc/min or less, particularly in the range of 0.8 cc/min to 15 cc/min.

In FIG. 1, 01 is a base cylinder, which is fixed to a rotating shaft 02 which also serves to hold the cylinder.

Further, the rotating shaft 02 is rotated by a rotating motor 03 at a predetermined rotational speed.

On the other hand, a gun 05 for discharging a beam-shaped coating liquid 04
is placed on a pedestal 06 of a transverse feed mechanism, and moves in a direction parallel to the rotation axis direction of the base cylinder 01. Also,
Gun 05 is connected to tank 09 via filter 08 and outlet pipe 07. Compressed air introduced by the air pipe 10 pressurizes the paint in the tank 09 to the pressure determined by the gauge 11, and the paint is sent from the tip nozzle 2 of the gun 05 (not shown) via the filter 08 and the outlet pipe 07. It is discharged.

When actually applying coating using this device, the switch for the transverse feed mechanism of the gun and the air switch of the gun needle are set, and the beam 04 is discharged from a predetermined position of the base cylinder 01. At the same time, turn on the rotation motor and rotate the rotating shaft holding the base cylinder. As shown in FIG. 2, a nozzle tip 17 provided at the tip of the gun 05
The beam-shaped coating liquid 04 discharged from the base cylinder 01 has a thread-like pattern 16 on the base cylinder 01.
By adhering in a spiral shape and leveling, the coating film 1
5 is deposited. The coating film generation process by leveling is
It is as shown below. That is, the base cylinder 0
Due to the collision energy of the paint, the surface tension of the paint, and the surface tension of the object to be coated, the adhered spool-shaped paint shown in step 1 gradually spreads over a wide area, causing adjacent paints to come into contact with each other and cause the coating surface of the object to be coated. cover it without any gaps. Then, after an appropriate amount of time has elapsed due to the surface tension and diffusivity of the paint and the surface tension of the object to be coated, the initial unevenness of the coating film, which had occurred in accordance with the pitch, is leveled and a smooth surface is formed. Note that the paint applied in a spool shape may be applied so that the ends of the paint overlap. Furthermore,
It is also possible to make the surface smoother by using a hood to control paint solvent vapor.

FIGS. 4a and 4b show specific examples of paint discharge ports.

Figure 4a shows a standard single outlet nozzle tip 1.
2(a), but in order to increase the coating speed, the nozzle chip 12(b) may have a large number of ejection ports, such as the nozzle chip 12(b) having three ejection ports as shown in FIG. 4b.

The present invention will be explained below based on Examples.

Furthermore, it is effective to heat the entire cylindrical or cylindrical mold in order to speed up the drying rate of the formed coating film.

The thickness of the annular film produced in the above manner is determined by the rotational speed of the cylindrical mold, the moving speed of the discharge port, the discharge speed of the solution, the concentration of the solution, etc., but a thickness of -5 μm or more can usually be suitably produced.

The present invention will be further explained below with reference to Examples.

Example-1 Polyamic acid, which is a precursor of polyimide resin, was
The solid content was adjusted to 10% with '-dimethylacetamide. The viscosity of the solution at this time was 2 poise at 30°C.

As a cylindrical type, made of stainless steel with an inner diameter of 50 mm and an outer diameter of 5 mm.
After setting it in a holder using one with a diameter of 5 mm and a length of 300 mm, it was rotated at a rotation speed of 120 RPM. Next, using a single-hole type discharge port with a diameter of 100 μm, the discharge pressure was set to 2.
Adjust the air pressure so that it becomes K g / c rd,
A coating film was formed by discharging the solution over a width of 10 mm to 290 mm in the longitudinal direction of the outer peripheral surface of a cylindrical mold. The coating conditions at this time were such that the moving speed of the discharge port was 200 mm/min, and the distance between the discharge port and the cylindrical mold was 1.0 mm. After application, 120
Keeping the rotation speed at RPM, dry the cylindrical mold with a hair dryer for 10 minutes.
After heating to 0°C and drying for 30 minutes, the cylindrical mold was removed, and firing imidization was performed for 15 minutes in a high-temperature furnace set at 350°C.

5 Next, the cylindrical mold taken out from the high-temperature furnace was immersed in water and cooled to room temperature, and then the polyimide film formed into an annular shape was peeled off from the cylindrical mold.

The thickness of the obtained annular polyimide film was 30 μm on average within the range of 5 mm to 275 mm in the longitudinal direction of the formed annular film, and the overall thickness unevenness was ±2 μm or less. Also, the surface roughness of the air surface is R, = 0.3 to 0.
It was 4 μm.

Comparative Example-1 Spray coating was performed using the same solution as in Example 1. The drying and imidization conditions were the same as in Example 1. As a result, the opposite surface that is not in contact with the cylindrical mold (
The measurement results of the surface roughness of the air surface are R, = 3.0 to 4.
．． It became an annular film with a diameter of 0 μm and some air bubbles, and was cut off from the cylindrical mold when it was removed.

Comparative Example-2 Using a polyamic acid solution prepared in the same manner as in Example 1 and a cylindrical mold having the same shape and material as in Example 1, the cylindrical mold was immersed in the polyamic acid solution, and the cylindrical mold was A coating film of polyamic acid solution was formed on the inner surface.

Next, the cylindrical mold with the coating film was placed in an upright position for 10 minutes.
After drying for 30 minutes in a dryer set at 0° C., it was imidized in the same manner as in Example 1 and further combed to obtain a cyclic polyimide film.

The thickness of this annular film is 5 m in the longitudinal direction of the film.
The average thickness was 25 μm between m and 295 mm, but the overall thickness unevenness was ±10 μm, and the thickness increased from the top to the bottom of the cylindrical mold during drying. Moreover, the polyimide film was also formed on the inner surface of the cylindrical mold, which was an unnecessary part.

[Other Examples]

Example 2 The procedure was the same as in Example 1, except that three-hole type discharge ports each having a diameter of 100 μm were used, and the moving speed of the discharge ports was 600 mm/min, and the air pressure was 6 K g / c g. As a result of manufacturing a cyclic polyimide film 7, a cyclic polyimide film with an average thickness of 25 μm and an overall thickness unevenness of ±2 μm was obtained.

Example 3 Using polyetherimide as an organic polymer and methylene chloride as a solvent, a solution was adjusted to have a solid content of 10%. The cylindrical type is made of Gauss and has an inner diameter of 100 mm.
A device with an outer diameter of 110 mm and a length of 300 mm was used, and after being set in a cylindrical holder, it was rotated at a rotational speed of 12 ORPM and maintained without being heated. Next, the diameter is 100μm
Using a 1-hole type discharge port, the discharge pressure is 3K with a gear pump.
g/crd and the solution is 10 m in the longitudinal direction of the outer surface of the cylindrical mold.
The solution was discharged in a width of 290 mm from m to form a coating film. The coating conditions at this time are that the moving speed of the discharge port is 200
mm/min, the distance between the discharge port and the inner surface of the cylindrical mold is 10 mm
And so. After coating and drying by keeping the rotation speed at 12 ORPM for 10 minutes, the cylindrical mold was removed from the cylindrical mold holder, immersed in water, and the annular polyimide formed from the outer surface of the cylindrical mold was peeled off. The thickness of the obtained annular polyimed film was 30 μm on average within the range of 5 mm to 275 mm in the longitudinal direction of the formed film, and the overall thickness unevenness was ±3 μm or less.

〔Effect of the invention〕

As described above, according to the method for producing an annular film of the present invention, by applying an organic polymer or its precursor to the outer peripheral surface of a cylindrical or cylindrical mold by a beam coating method, it is possible to apply the organic polymer or its precursor to the outer peripheral surface of a cylindrical or cylindrical mold. It has become possible to produce an annular film with stable physical properties that has a good air surface roughness and does not entrain air.

Furthermore, compared to the dip coating method, it uses the minimum amount of solution required, and it is easy to form an annular film of uniform thickness from an organic polymer or its precursor, which requires the use of a solvent with a slow volatilization rate. Now I can do it.

[Brief explanation of drawings]

Figure 1 shows a schematic diagram of an apparatus for beam coating an organic polymer or its precursor solution onto the outer peripheral surface of a cylindrical or cylindrical mold. FIG. 3 shows a conceptual diagram of coating film formation according to the present invention, and FIGS. 4a and 4b show specific examples of solution discharge ports. 01...Cylindrical or cylindrical mold 02...Rotating shaft for holding cylindrical or cylindrical mold 03...
・Rotary motor 04...Coating liquid beam 05...Gun 06...Horizontal feeding mechanism frame 07...Solution outlet pipe 08...Filter 09...Solution paint tank 10...Air pipe 11...Pressure gauge 12...Nozzle tip 12(a)...1-hole beam tip (side view) 13.
...Dip for 1-hole beam (front view) 0 2(b)...For 3-hole beam (side view) 4...Tip for 3-hole beam (front view) 5...Coating film in leveled state 6... Paint film before leveling 6 15

Claims (1)

[Claims] (1) A solution of an organic polymer or its precursor is applied to the outer surface of a rotating cylindrical or cylindrical mold, and after drying and solidification or completion of the reaction, it is peeled off from the cylindrical mold to produce an annular film. A method for producing an annular film, characterized in that the solution is sprayed continuously in a streaky manner without being substantially atomized from a movable discharge port on the outer surface of a cylindrical mold from one end to the other end. Method.