JP7270936B2 - Dryer and drying method - Google Patents

Description

The present invention relates to dryers and drying methods. In particular, the present invention relates to a dryer and drying method for drying an object after development.

Photopolymer plates for flexographic printing have been developed using harmful halogen-based solvents with low boiling points. However, due to environmental concerns, the use of halogen-based solvents has become unusable. Worldwide, hydrocarbon-based solvents are being used as alternative solvents.

JP 2010-000442 A

However, when developing with a hydrocarbon solvent, the boiling point is high and the drying process takes a long time. It takes about 2 hours at about 60°C to 80°C. As a result, the total manufacturing process time is lengthened.
SUMMARY OF THE INVENTION It is an object of the present invention to provide a drying apparatus and a drying method capable of drying an object in a short time.

In order to solve the above-mentioned problems, there is provided a gas piping section for taking in air, a heat treatment section connected to the gas piping section for holding an object, and a hot air from the gas piping section that is made into a turbulent flow and provided to the heat treatment section. A dryer containing a turbulent section is used.
In addition, a drying method is used that includes the steps of sucking air to generate hot air, making the hot air turbulent, directing the turbulent air to an object, and recovering the turbulent air.

According to the present invention, an object can be dried in a short time.

FIG. 1 is a plan view of the dryer of the embodiment. FIG. 2 is a perspective view of the dryer of the embodiment. FIG. 3A is a perspective view of a first turbulence section of the embodiment; FIG. 3B is a perspective view of the first turbulence section of the embodiment; FIG. 3C is a plan view of the first turbulence section of the embodiment. FIG. 3D is a plan view of the first turbulence section of the embodiment. FIG. 3E is a plan view of the first turbulence section of the embodiment. FIG. 4A is a cross-sectional view of the vicinity of a hot-air concentrated portion according to the embodiment. FIG. 4B is a plan view of the vicinity of the hot-air concentrated portion of the embodiment.

Although the resin plate for flexographic printing will be described below as an object, other objects may be used.
(manufacturing process)
First, the manufacturing process of a resin plate for flexographic printing will be described.

A photosensitive resin plate for flexographic printing is produced by subjecting a photosensitive resin layer to imagewise exposure, development, and drying.
<Formation of photosensitive resin layer>
The composition for forming the photosensitive resin layer is a composition containing a thermoplastic elastomer, a photopolymerizable unsaturated monomer and a photopolymerization initiator as main components.

Examples of the thermoplastic elastomer include copolymers of monovinyl-substituted aromatic hydrocarbons such as styrene and conjugated dienes such as butadiene and isoprene. Specific examples include styrene-butadiene-styrene block copolymers, styrene-isoprene-styrene block copolymers, and styrene-isoprene/butadiene-styrene block copolymers. The thermoplastic elastomer may be used singly or in combination of two or more.

The thermoplastic elastomer is blended in the photosensitive resin composition in an amount of 30 to 95% by weight, preferably 50 to 85% by weight. If the amount is less than 30% by weight, a composition having excellent rubber elasticity cannot be obtained. If the amount is more than 95% by weight, it becomes difficult to form patterns with excellent reproducibility.

Examples of photopolymerizable unsaturated monomers include esters such as acrylic acid, methacrylic acid, fumaric acid and maleic acid, derivatives of acrylamide and methacrylamide, and allyl esters. , styrene, styrene derivatives, and N-substituted maleimide compounds. Specifically, diacrylates and dimethacrylates of alkanediols such as ethanediol, propanediol, butanediol, hexanediol, nonanediol; diacrylates and dimethacrylates such as diethylene glycol, dipropylene glycol, polyethylene glycol; (Meth)acrylate, dimethyloltricyclodecane di(meth)acrylate, isobornyl (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, pentaerythritol tetra(meth)acrylate, diacryl phthalate; fumaric acid diethyl ester, fumaric acid dibutyl ester, dioctyl fumarate, distearyl fumarate, butyl octyl fumarate, diphenyl fumarate, dibenzyl fumarate, bis(3-phenylpropyl) fumarate, dilauryl fumarate, fumaric acid dibehenyl ester; dibutyl maleate, dioctyl maleate; N,N'-hexamethylenebisacrylamide and methacrylamide; triallyl cyanurate; vinyl toluene, divinylbenzene; Polymerizable unsaturated monomers may be used singly or in combination of two or more.

Furthermore, the photopolymerization initiator is not particularly limited as long as it has the ability to initiate polymerization of the polymerizable unsaturated monomer in response to non-infrared radiation, and is appropriately selected according to the physical properties of the desired photosensitive resin layer. can be selected. For example, aromatic ketones such as benzophenone, benzoin ethers such as benzyl dimethyl ketal, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether, α-hydroxyketones, α-aminoketones, oxime esters, acylphosphine oxides compound. A photoinitiator may be used individually by 1 type, and may be used in combination of 2 or more types.

In addition to the above components, the photosensitive resin layer contains a plasticizer, a processing stabilizer, a liquid rubber, a thermal polymerization inhibitor, a sensitizer, a colorant, an ultraviolet absorber, an antihalation agent, an anti-ozonant, an inorganic Additives such as fillers and flame retardants may be added alone or in combination of two or more depending on the performance required.

The photosensitive resin layer can be formed by various methods. For example, it is formed from a photosensitive resin composition containing a thermoplastic elastomer, a polymerizable unsaturated monomer, and a photopolymerization initiator. For example, if the composition is as described above, the raw materials to be blended are dissolved in a suitable solvent such as chloroform, tetrachlorethylene, methyl ethyl ketone, toluene, etc., mixed, cast in a mold, and the solvent is removed. It can be evaporated and used as a photosensitive resin plate as it is. Alternatively, the mixture can be kneaded with a kneader or roll mill without using a solvent, and molded into a photosensitive resin plate having a desired thickness by an extruder, an injection molding machine, a press, or the like.

The thickness of the photosensitive resin layer is usually within the range of 0.5 mm to 9.0 mm.
The photosensitive resin layer obtained as described above is pressed against a resin film or sheet such as polyethylene terephthalate, polyethylene, polypropylene, etc., or a metal plate such as iron, aluminum, copper, etc. to form a photosensitive resin layer. .

<Image exposure, development, drying>
Imagewise exposure is performed by selectively irradiating actinic rays onto the photosensitive resin layer through a negative mask or a mask layer coated with a thin film of a carbon layer that has been laser ablated, and the unexposed portions are washed out with a developer and dried. to produce a relief plate for flexographic printing having rubber elasticity.

The image exposure is carried out by irradiating for about 2 to 20 minutes using a light source such as an extra-high pressure mercury lamp, a chemical lamp, or an LED. Development processing is carried out after exposure, and the developer used is preferably an aromatic solvent or one to which a paraffinic solvent or a naphthenic solvent is added, to which water and a surfactant are added. An emulsion solvent is also suitably used. Examples of the aromatic solvent include toluene, xylene, methylethylbenzene, propylbenzene, isopropylbenzene, trimethylbenzene, tetramethylbenzene, tert-butylbenzene, diethylbenzene, amylbenzene, diamylbenzene, amyltoluene, cymene, or Mixtures of these compounds (eg, crude oil or carbonized coal naphtha) can be used, and these compounds can be used singly or as a mixture of two or more of them.

Examples of commercially available mixtures include Solvesso 100, Solvesso 150, Solvesso 200 (trade names, manufactured by Exxon Chemical Co., Ltd.), Swazol 100, Swazol 200, Swazol 310, Swazol 1000, Swazol 1500, and Swazol 1800 (trade names, Maruzen manufactured by Petrochemical Co., Ltd.). Examples of paraffinic hydrocarbons include heptane, octane, nonane, methyloctane, decane, undecane, dodecane, tridecane, etc. These compounds may be used alone or in combination of two or more. Furthermore, naphthenic hydrocarbons include, for example, dimethylcyclohexane, methylethylcyclohexane, propylcyclohexane, trimethylcyclohexane, butylcyclohexane, etc. These may be used singly or in combination of two or more. In particular, these solvents are interfacial with water, higher alcohol sulfate sodium salts, aliphatic quaternary ammonium salts, aliphatic amine salts, polyoxyethylene alkyl ethers, polyoxyethylene glycerin aliphatic esters, polyethylene glycol aliphatic esters, and the like. An emulsion developer containing an activator can be preferably used because of its good reproducibility of relief and high safety.

Since the photosensitive resin is formed from a photosensitive resin composition containing a thermoplastic elastomer, a polymerizable unsaturated monomer, and a photopolymerization initiator, it has stickiness when the negative mask is laminated on the photosensitive resin. As a result, the negative mask may be damaged, air may be trapped between the photosensitive resin and the negative mask, and a faithful image cannot be formed. Therefore, compounds that can easily dissolve the coating layer in the developer composed of the above components, such as n-butyl isobutyrate, isobutyl-n-butylate, isobutyl isobutyrate, isobutyl-2-methyl-butyrate, isobutyl-3 -methyl-butyrate and the like can be added.

As a developing method using the developer, conventional methods such as brush development and spray development are used.
The embodiments of the present application relate, as an example, to a drying method and a dryer for removing the developer swollen on the surface of the photosensitive resin or the photosensitive resin layer by drying.

In addition, it can also be used for drying other objects.
(Embodiment)
In FIG. 1, the plane block diagram of the dryer 100 of embodiment is shown. FIG. 2 shows a perspective view of the dryer 100. As shown in FIG.

<Configuration>
The dryer 100 has a heat treatment section 31b and a gas pipe section 31a.
<Gas piping portion 31a>
The thermal processing section 31b has a first turbulent flow section 17a, a second turbulent flow section 17b, and a holding section 16b that holds the target object 16a.

The gas pipe section 31a has an intake passage 10a, a first hot air supply passage 10c, a second hot air supply passage 10b, a hot air recovery passage 10d, an exhaust passage 10f, and a connecting passage 10e.
The intake passage 10a has an intake valve 19a and takes in air from the outside. Hot air is produced by the heating unit 14 . An air flow is generated by the fan 13a.

From the air intake passage 10a, the first hot air supply passage 10c and the second hot air supply passage 10b spread in the left-right direction, and send the hot air to the hot air concentrated portion 31c. The hot air concentrating part 31c concentrates hot air in a certain range and blows it to the first turbulent flow part 17a and the second turbulent flow part 17b of the heat treatment part 31b.
The hot air collection passage 10d has a fan 13b and draws in the hot air from the heat treatment section 31b. The hot air recovery passage 10d is positioned between the left and right first hot air supply passages 10c and the second hot air supply passages 10b. Preferably, the first hot air supply passage 10c and the second hot air supply passage 10b are positioned at both ends of the heat treatment section 31b, and the hot air recovery passage 10d is positioned in the center of the heat treatment section 31b. The entire heat treatment section 31b can be uniformly flowed with hot air.

The exhaust passage 10f receives the hot air from the hot air recovery passage 10d and releases it to the outside.
The connection passage 10e is a passage that connects the hot air recovery passage 10d and the intake passage 10a. The connecting passage 10e is used for circulating hot air.

A plurality of valves are arranged. The intake passage 10a has an intake valve 19a. The connecting passage 10e has a connecting valve 19b. The exhaust passage 10f has an exhaust valve 19c.
Each aisle is opened and closed.

Furthermore, there is a gas detector 18 in the hot air collection passage 10d. The results of the gas detector 18 open and close the three valves.
<Heat treatment unit 31b>
The thermal processing section 31b has a first turbulent flow section 17a, a second turbulent flow section 17b, and a holding section 16b that holds an object 16a. Moreover, the thermal processing section 31b has a first thermal processing section 31b1 and a second thermal processing section 31b2, which are separate rooms, in a stacked state. Although there are two chambers in FIG. 2, it may be two or more chambers. Hot air is sent to each room.

The first turbulent flow section 17a and the second turbulent flow section 17b turbulate the hot air from the first hot air supply passage 10c and the second hot air supply passage 10b, respectively, and irradiate the object 16a. In addition, there are a plurality of first turbulent flow portions 17a and a plurality of second turbulent flow portions 17b. Details are described below.
The holding part 16b holds the target object 16a. It is a structure that can irradiate hot air (turbulence) above and below the object 16a. For example, mesh plates. The object 16b can be efficiently dried by being heated by turbulent hot air from above and below.

Furthermore, the heat treatment section 31b has a first pressure gauge 15b. It detects the pressure of the heat treatment section 31b and controls the fan 13b. The thermal processing section 31b is brought into a decompressed state, and the evaporation of the solvent from the object 16a is quickly removed.
A second pressure gauge 15a is provided in the first hot air supply passage 10c of the gas pipe portion 31a. The pressure in the first hot air passage 10c is detected and the fan 13a is controlled. The heat treatment section 31b connected to the first hot air passage 10c is decompressed to quickly evaporate the solvent from the object 16a.

With the first pressure gauge 13a and the second pressure gauge 13b, the heat treatment section 31b can be uniformly decompressed.
<Process>
Air is taken in by a fan 13a from an intake passage 10a. The air is heated by the heating unit 14 . The hot air is sent to the first hot air supply passage 10c and the second hot air supply passage 10b.

The first hot air supply passage 10c and the second hot air supply passage 10b supply hot air to the heat treatment section 31b.
In the heat treatment section 31b, the air is made into a turbulent flow, that is, in a spiral shape by the first turbulence section 17a and the second turbulence section 17b, and is blown onto the surface of the object 16a of the heat treatment section 31b.

Although not shown, the temperature of the thermal processing section 31b is monitored, and the heater of the heating section 14 is adjusted so as to obtain a predetermined temperature and temperature profile.
Hot air is usually circulated. That is, the connection valve 19b is opened, the intake valve 19a and the exhaust valve 19c are closed, and the hot air is circulated.

When the gas detector 18 detects the saturation of the gas evaporated from the object 16a, the intake valve 19a and the exhaust valve 19c are opened to perform intake and exhaust for several seconds to lower the gas saturation concentration. If necessary, all the gas (hot air) may be replaced.
Depending on the type of solvent contained in the object 16a to be dried, the gas detector 18 is replaced with a corresponding one. Gases are mostly combustible gases.

In addition, the pressure in the heat treatment section 31b is constantly monitored by the second pressure gauge 15a and the first pressure gauge 15b. The fans 13a and 13b are adjusted so that the pressure is reduced slightly. By reducing the pressure, the hot air can be replaced more easily and quickly.
Specifically, the normal pressure is 101.3 kpa, and the reduced pressure is in the range of -80 kpa to -100 kpa.

Since the recovery fan 13b is provided in the hot air recovery passage 10d, the volume of the recovery air can be increased, and the heat treatment section 31b can be brought into a decompressed state. Hot air (turbulence) diffused by the vortex can be applied to the object 16a. In addition, by reducing the pressure in the heat-treating section 31b, the boiling point of the solvent is lowered, the solvent swollen in the object 16a is easily removed, and the object 16a is quickly dried.

<Turbulence section>
3A and 3B show perspective views of the first turbulent flow portion 17a. The same applies to the second turbulent flow portion 17b, so the first turbulent flow portion 17a will be described. 3C and 3D show plan views of the first turbulent flow portion 17a viewed from above. The first turbulent flow portion 17a has a columnar shape, an asymmetric cross section, and an eye-shaped cross section. A plurality of first turbulent flow portions 17a stand in the vertical direction. FIG. 3E is an enlarged cross-sectional view of the first turbulence portion 17a.

The shape of the first turbulent flow portion 17a is columnar with an elongated elliptical shape (eye shape) in cross section. However, the ellipse is not symmetrical, the upper side is longer than the lower side, and the ellipse is curved. Therefore, the flow of hot air is slower upstream 21a than downstream 21b. As a result, the hot air becomes turbulent 34 .
As shown in FIG. 3A, the longitudinal direction of the first turbulent flow portion 17a is arranged perpendicular to the direction of hot air flow. A difference is generated between the upstream 21a and the downstream 21b, and in particular, a vortex turbulent flow 34 that is swirled up from the downstream 21b is generated near the edge 33 (corner portion) of the first turbulent flow portion 17a.

In FIG. 3B, the first turbulent flow portion 17a is tilted with respect to FIG. 3A (although not shown, there is a rotating mechanism). Inclining makes a difference between the upstream 21a and the downstream 21b, and the turbulent flow 34 is more likely to occur. Therefore, it is preferable that the direction of the first turbulent flow portion 17a can be changed arbitrarily.
As shown in FIG. 3E, the cross section of the first turbulent flow portion 17a has a shape in which the three vertices of a triangle are rounded.

The angle θ2 on the side receiving the hot air should be larger than the angle θ1 on the side emitting the hot air. Since the turbulent flow 34 is generated at the end portion 33 at the angle θ1, the angle θ1 is made small. The angle θ1 is preferably 20 to 30 degrees. The angle θ2 is preferably greater than the angle θ1 and 30 to 50 degrees.
The tilt angle α is such that the more the hot air is tilted, the more the hot air becomes turbulent 34, and the angle α is the center plane 32 of the hot air passage (or with respect to the tube through which the hot air flows, or with respect to the hot air flow). ±10 degrees is preferred. The center plane 32 of the hot air passage is the center of the hot air passage and is a plane parallel to the vertical direction.

The horizontal direction (side direction) of the first turbulent flow portion 17a is preferably columnar and has a constant cross section. Air resistance is uniform, and turbulent flow 34 can be uniformly generated, which is preferable.
In order to uniformly generate the turbulent flow 34, the plurality of first turbulent flow sections 17a are inclined or evenly arranged in the horizontal direction within the first hot air supply passage 10c.

FIG. 4A is a cross-sectional view of the vicinity of the hot air concentrated portion 31c. FIG. 4B is a plan view of the vicinity of the hot air concentration portion 31c.
There is a hot air concentration portion 31c in the first hot air supply portion 10c before the first turbulent flow portion 17a. The hot air concentration portion 31c concentrates the hot air and guides it to the first turbulence portion 17a. Make much of the hot air turbulent 34 .

The hot air becomes turbulent flow 34 in the first turbulent flow section 17a and is guided to the upper and lower surfaces of the object 16a.
In particular, the turbulent flow 34 is generated around the edge portion of the first turbulent flow portion 17a. For this reason, the end portion 33 of the first turbulent flow portion 17a is positioned substantially in the center of the region constricted by the hot air concentration portion 31c.

As can be seen from Figures 4A and 4B, a turbulent flow 34 flows parallel to the surface of the object 16a. This effectively removes solvent that evaporates from the object 16a.
Since the object 16a is heated from the upper and lower surfaces by the turbulent flow 34 of the hot air, a difference is less likely to occur between the first heat treatment chamber 31b1 and the second heat treatment chamber 31b2.

<effect>
Due to the hot air turbulence 34, the object is dried efficiently.
<Overall>
The material of each element is metal or a compound having heat resistance. The temperature varies depending on the object 16a. Since the solvent and the like are evaporated, a material that can withstand temperatures of about 100 to 400°C is used.

The dryer of the present invention is widely used as a dryer. Various members can be targeted as the object.

DESCRIPTION OF SYMBOLS 10a... Air intake passage 10b... 2nd hot air supply passage 10c... 1st hot air supply passage 10d... Hot air recovery passage 10e... Connection passage 10f... Exhaust passage 13a, 13b... Fan 14... Heating part 15a... Second pressure gauge 15b First pressure gauge 16a Object 16b Holding portion 17a, 17b Turbulence portion 17a First turbulence portion 17b Second turbulence portion 18 Gas detection Unit 19a: intake valve 19b: connection valve 19c: exhaust valve 21a: upstream 21b: downstream 31b: heat treatment section 31a: gas pipe section 31b1: first heat treatment section 31c: hot air concentration section 31b2 . . 2nd heat treatment section 32 .

Claims (11)

a gas pipe section for taking in air;
a heat treatment unit connected to the gas pipe unit and holding an object;
a turbulent section for making hot air from the gas pipe section turbulent and providing it to the heat treatment section;
The turbulence portion has a columnar shape with an asymmetrical cross section,
The turbulence section has an elliptical cross-section and is not line-symmetrical and generates a vortex turbulent flow. 2. A dryer according to claim 1, wherein said ellipse is not axisymmetric and has a curved upper side longer than a lower side. a gas pipe section for taking in air;
a heat treatment unit connected to the gas pipe unit and holding an object;
a turbulent section for making hot air from the gas pipe section turbulent and providing it to the heat treatment section;
The turbulence portion has a columnar shape with an asymmetrical cross section,
The cross section has a shape in which three vertices of a triangle are rounded,
The angle θ2 of the vertex on the side receiving the hot air is larger than the angle θ1 of the vertex on the side emitting the hot air,
The turbulence section is a dryer that generates vortex turbulence. 4. The dryer according to claim 3, wherein the angle θ1 is 20 to 30 degrees and the angle θ2 is 30 to 50 degrees. 5. The dryer according to any one of items 1 to 4, wherein there are a plurality of said turbulent flow sections, and they are arranged so that the direction thereof can be changed arbitrarily. 6. The dryer according to claim 5, wherein the direction is within ±10 degrees with respect to the central plane of the hot air passage through which the hot air is sent from the gas pipe section. The gas pipe section has an intake passage for taking in air and an exhaust passage for discharging the air,
the air intake passage heats the air and supplies the hot air to the first hot air supply passage and the second hot air supply passage;
The dryer according to any one of claims 1 to 6, wherein the first hot air supply path and the second hot air supply path supply the hot air to each of the turbulence sections. 8. The dryer according to claim 7, wherein the first hot air supply path has a hot air concentration section for concentrating the hot air before supplying the hot air to the turbulence section. 9. The dryer according to claim 8, wherein the end of the turbulent flow portion is positioned at the center of the hot air squeezed by the hot-air concentrated portion. 10. The dryer according to any one of 1 to 9, wherein the turbulence section is inclined toward the hot air. a step of sucking air to generate hot air;
making the hot air turbulent;
directing said turbulence to an object;
a step of recovering the turbulent flow, and
A drying method used in the dryer of any one of claims 1-10.

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