JP2002225113A - Adherend removing device on surface of roll - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that a method for removing an adherend by a corona discharge or an ultraviolet ray has a low removing capability and is not hence satisfied, an influence of an ozone or the ray generated by the conventional method to a human body is large, many accessory facilities such as an ozone decomposing facility, a ventilating facility or an ultraviolet ray leakage countermeasure or the like is required so that an initial cost and a running cost are raised. SOLUTION: An adherend removing device on a surface of a roll heats the adherend on the surface of the roll by an infrared ray and removes the adherend. In this case, a wavelength of the infrared ray is 2.8 to 25 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing deposits on a roll surface, and more particularly to a method for producing a thermoplastic polymer film or removing organic substances attached to the roll surface during processing. .

[0002]

2. Description of the Related Art Conventionally, a thermoplastic polymer film (hereinafter, referred to as a thermoplastic polymer film)
Organic substances and the like are deposited over time on the roll surface used in the production or processing of the film or the film is processed and stains are generated. Therefore, a physical cleaning method (rubbing with a brush, wiping with a cloth, etc.) is indicated. ), A chemical cleaning method (indicating dissolving with a solvent or the like and wiping off), and a cleaning tool or the like for mechanically operating the chemical cleaning method to remove stains on these rolls.

[0003] However, in such a conventional method, when the brush is rubbed or wiped with a cloth, the adhering matter is generated. In the case of the chemical cleaning method, the solvent used for removing the adhering matter remains and the roll operation is performed. There was a problem that when they were cleaned during cleaning, they were transferred to the film side. For this reason, the removal of organic substances adhered to the roll surface is performed after the production of the film or the processing equipment is stopped. Outbreak was inevitable.

To solve these problems, Japanese Patent Application Laid-Open No. 57-514 discloses
26. In recent years, a method disclosed in JP-A-10-315306 has been proposed. The former is a method of decomposing and removing the deposits on the roll by corona discharge, and the latter is a method of decomposing and removing the deposits by ultraviolet rays.

[0005] JP-A-57-51426 and JP-A-Hei 10-
Both 315306 are non-contact with respect to the removal of the deposit, and the method of decomposing the deposit itself enables the production of a film or the continuous removal of the deposit without stopping the processing apparatus. The common feature of these methods is that when oxygen present in the atmosphere generates ozone due to energy application by corona discharge or energy application by ultraviolet rays, a part of the ozone is decomposed into oxygen again. It utilizes the principle of decomposing organic substances by the oxidizing power of active oxygen (FIG. 2). However, these methods have some problems and are not satisfactory.
The problems are described below.

(Treatment capacity) Although the oxidizing action of active oxygen is very strong, its treatment capacity is low. For more information,
Oxidation by active oxygen only works to a depth of about several angstroms of the surface layer, and instantaneously decomposes deposits formed in micron-order thickness on rolls etc. with the ability to modify the material surface Energy is too small. Therefore, long-time irradiation or continuous irradiation is required to remove the attached matter, but there is still a problem that the treatment ability is low, so that it can be applied only to the case where the amount of the attached matter is extremely small.

[0007] In the method using ultraviolet light, in addition to the generation of active oxygen by the energy of ultraviolet light, the wavelength range coincides with the natural vibration of carbon, hydrogen and oxygen molecules constituting the organic substance, so that the method directly acts on the attached substance and acts on the organic substance. Has the effect of promoting decomposition. However, as in the former case, the processing capacity acts only up to a depth of about several angstroms of the surface layer, and the shortage of the processing capacity cannot be overcome even with ultraviolet rays.

(Safety) The principle of removing adhering substances is the oxidizing action of active oxygen by the cycle of generation and destruction of ozone, and the generation of ozone is a prerequisite, but ozone is a gas that has an adverse effect on the human body. If high-purity ozone is inhaled, lung tissue is destroyed and death occurs.

[0009] Ultraviolet rays also have an adverse effect on the human body,
If ultraviolet light enters the field of vision for a long time,
This leads to blindness, and in the case of skin, skin irritation, and eventually skin cancer.

(Cost) In consideration of the effect on the human body of the worker, it is necessary to introduce an ozone decomposing device and install a ventilation system for the generated ozone, and no leakage of ultraviolet rays occurs. Since it is necessary to deal with equipment, the cost of equipment is enormous. Further, the ultraviolet lamp is expensive and has a shorter service life than general halogen lamps and mercury lamps.

(Other Problems) In corona discharge, the treatment portion and the discharge portion need to be in the same atmosphere, and complete isolation cannot be performed in principle. Furthermore, corona discharge,
That is, since a spark is generated, it cannot be introduced into a process that requires explosion-proof specifications. In addition, ultraviolet light also deteriorates peripheral devices and members other than attached matter,
There is a problem that the life is significantly shortened.

[0012]

The problem to be solved by the present invention is to remove the adhered substance on the roll surface by corona discharge or ultraviolet irradiation, and to improve the processing ability, safety, cost, etc. It is intended to provide a removing device.

[0013]

As a result of investigations by the present inventors, it is possible to remove the deposits on the roll surface by heating the deposits on the roll surface with infrared rays, and further solve the above-mentioned problems. I found that I got it.

That is, the present invention provides an apparatus for removing deposits on a roll surface, which irradiates infrared rays to the surface of a roll for transporting a film and heats off the deposits.

[0015] Preferably, the peak wavelength of the infrared ray is 2.8 to 25 µm.

[0016] Preferably, the source of infrared rays is a halogen lamp.

Further, in another aspect of the present invention, the surface of a roll for transporting the film is irradiated with infrared rays, and the film is subjected to a forming process while heating and removing the attached matter. Provide a way.

Preferably, the peak wavelength of the infrared ray is 2.8.
μm to 25 μm.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Production and Processing Method) In the production of a film, for example, a material melted by heat and shear force by an extruder is formed into a wide molten film by a T-type die and held in a roll to form a film. There are a T-die method for processing and a calendering method in which a material in a semi-molten plastic state is rolled stepwise by several heating rolls. Alternatively, examples of film processing include a stretching process in which the film is stretched while being heated, a surface process in which a pattern such as unevenness is transferred to the surface, and a multilayer process in which another material is applied to the surface of the film.

(Principle of formation of deposits) Most of the stabilizers, physical properties, and processability modifiers added to the thermoplastic polymer material have boiling points much lower than the processing temperature, and are added to the material during processing. The stabilized stabilizer, plasticizer, lubricant and the like evaporate or sublime and become gaseous, which solidifies on the roll surface and adheres. On the other hand, it bleeds from the material and is transferred and adhered to the roll. Further, low-molecular-weight substances and the like generated by the decomposition of the material due to the heat at the time of production also accumulate on the roll surface over time and become soiled. Soil attached to these rolls is eventually transferred to the film side, and the stain is transferred to other rolls during film processing. Dirt accumulates and spreads on the roll surface that the film contacts in a bridging manner.

(Principle of Heating by Infrared) Molecules are composed of atoms and atomic bonds, and organic substances are composed of aggregates of the molecules bonded in various forms. In addition, they are constantly vibrating due to stretching vibration in which the distance between atoms changes and bending vibration in which the bonding direction between molecules changes, and the vibration shows a unique frequency depending on the molecular structure of the organic matter .
This vibration is called natural vibration or natural frequency. When radiant energy having the same frequency as the natural frequency of these organic substances is given, a kind of resonance phenomenon occurs and the vibration is activated, and as a result, the temperature of the organic substances rises. Resonance does not occur for radiant energies whose frequency and frequency do not match,
Reflected or transmitted radiant energy is not absorbed in the substance. From this, the organic material can be heated by examining the natural vibration of the organic material and applying radiant energy having a wavelength corresponding to the natural frequency. Further, the natural frequency of each organic substance can be examined by an infrared absorption spectrum.

(Infrared Absorption Spectra of Deposits) Deposits are organic as guessed from the cause of contamination,
Most organic matter is 3600-2800cm ^-1 and 1750-
It has a large absorption peak in the absorption wave number region of 400 cm ^-1 .
From the conversion formula of the following formula 1, 2.8 to 3.6 μm and 5.7 to 2
It can be seen that the natural vibration is concentrated at 5 μm.

[0023]

(Equation 1) (Principle of Removal of Deposits) Since the deposits, once in a gas state, solidify on the roll surface and adhere, the deposits can be removed again by heating the deposits to a boiling point or higher to bring them into a gaseous state. . That is, the attached matter may be heated, and as a heating method, heating and removal can be performed by applying radiant energy (infrared rays) having a wavelength coincident with the natural vibration of the attached matter. In addition, while the natural vibration of an organic substance is in the wavelength range of 2 μm to 4 μm (middle infrared range), pottery, food,
Glass has a natural vibration in a region of 4 to 1000 μm (far-infrared region), and copper, solder, and metals have a natural vibration in a region of 0.8 to 2 μm (near-infrared region). By utilizing the difference between these natural vibrations (by giving radiant energy in the range of 2 μm to 4 μm), the organic material can be selectively and efficiently heated.

(Infrared Lamp) Examples of a lamp that emits a wavelength in the infrared region include a halogen lamp, a nichrome heater, a ceramic heater, and an opaque quartz heater. From Wien's law (the peak emission wavelength is proportional to the absolute temperature of the radiator), the peak emission wavelength can be changed by controlling the output. That is, the higher the temperature of the radiator, the lower the wavelength of infrared radiation can be emitted. Therefore, since the maximum temperature varies depending on the type of radiator, the wavelength of infrared light that can be emitted from the nichrome heater, the ceramic heater, and the opaque quartz heater is a wavelength having a peak at a minimum of 3 μm, and the halogen lamp has a higher temperature. Infrared radiation having a peak at 1 μm is possible. As described above, the natural vibration of the organic substance is 2 μm or more.
Since the wavelength is in the region of 4 μm (middle infrared region), a halogen lamp is preferably used in the apparatus for removing deposits on the roll surface of the present invention.

(Halogen lamp) The halogen lamp can condense the light with a mirror or the like to limit the processing portion or amplify the processing capability (heating temperature). For example,
When condensed with a lamp of 100V, 980W, φ2mm
It is possible to heat up to 1200 ° C. with the spot light. Also, the rising speed is very fast, and 400 seconds after one second.
The temperature reaches 800 ° C. after 2 seconds and 1200 ° C. after 4 seconds.
Further, these heating adjustments can be arbitrarily adjusted by power control, and various feedback controls can be easily constructed by a system combined with an infrared sensor. Furthermore, infrared rays are electromagnetic waves (same as light), and heating in vacuum, in an inert gas, or through glass is also possible. In addition, since it has the same wavelength as sunlight, there is no adverse effect on the human body and it is safe.
Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to the examples. In addition, typical additives were extracted and implemented, but are not limited to the examples.

(Mounting position of infrared lamp) The mounting position of the infrared lamp is typically 40 mm from the roll.
It is a position far away. If the roller is too far from the roll, it is necessary to increase the radius of curvature of the mirror for reflecting and condensing, so that the size of the apparatus is increased, and there is a possibility that the directly radiated infrared rays diverge to lower the condensing rate. On the other hand, if the mirror is too close to the roll, the radius of curvature of the mirror for reflecting and condensing must be reduced, which may require the use of a condensing mirror having a complicated structure.

If the width of the lamp substantially matches the roll width, the lamp may be fixed. However, if a wide lamp corresponding to a wide roll is not available, the lamp may be fixed in the width direction. It is also possible to make a round trip. In many cases, the deposits gradually adhere during continuous operation for a long period of time. Therefore, there is no particular problem even if a region where infrared rays do not shine during the reciprocation of the lamp is instantaneously generated. However, when the rotation cycle of the roll and the reciprocation cycle of the lamp coincide with each other, a portion to which infrared rays do not completely strike is formed, so care must be taken.

[0028]

EXAMPLES (Composition) 0.4 part of an additive was added to 100 parts of a cycloolefin resin (ZEONOR1420R, manufactured by Zeon Corporation). In addition, each additive is shown in Table 1. FIGS. 3 to 5 show infrared absorption spectra of typical additives.
Shown in

[0029]

[Table 1] (Construction of Experimental Apparatus) FIG. 1 shows an apparatus used in the embodiment, and a T-die 5 for extruding a molten material into a wide molten film,
It has a configuration in which a cast roll 4 for cooling and forming the film into a film shape, and an infrared lamp 1 is installed on a portion of the cast roll 4 where the film 4 is not in contact.

(Extrusion conditions) Cylinder temperature 270 ° C, T
Die temperature 270 ° C, cast roll temperature 130 ° C. A film was produced at a line speed of 30 m / min.

(Infrared Lamp) As the infrared lamp, a nichrome lamp was used in Example 1, and a halogen lamp (HYL25SERIES) manufactured by Hivec was used in Example 2.

(Example 1) Levels 1 to 9 and levels 10 to 1
A film was formed using each composition to which the nine additives were added. Incidentally, the roller portion not in contact with the film from the beginning of operation was irradiated with infrared rays by a nichrome lamp. Driving 3
From 0 minutes to 1 hour, stains on the cast roll were observed, but no white deposits were observed at all levels.

(Embodiment 2) Levels 1 to 9 and levels 10 to 1
A film was formed using each composition to which the nine additives were added. As a result, a white deposit was observed on the cast roll between 30 minutes and 1 hour. From that point on, the roller portion not in contact with the film was irradiated with infrared light by a halogen lamp. A few seconds after the emission, the white deposits present on the cast roll disappeared at all levels.

(Comparative Example) Levels 1 to 9 and 10 in Table 1
A film was formed using each of the compositions to which the additives Nos. To 19 were added. However, the cast roll did not emit infrared light. As a result, a white deposit was observed on the cast roll between 30 minutes and 1 hour.

[0035]

According to the present invention, it is possible to instantaneously heat, sublimate, or evaporate the deposits, and it is possible to continuously remove the deposits without stopping the production or processing of the film. It becomes possible. In addition, this device is a non-contact type using infrared rays and uses a material that does not absorb wavelengths in the infrared range, such as glass, to completely separate the light emitting unit and the processing unit (eg, roll unit). In addition, heating is possible even in a vacuum or an inert gas. Furthermore, the natural vibration of a general polymer organic substance is
While the infrared lamp used in this device emits radiant energy in the same wavelength range while the wavelength is concentrated in the wavelength range of 2 to 4 μm, metal parts such as rolls, or
Radiant energy is hardly absorbed by ceramics, glass, and the like, and organic materials can be selectively and efficiently heated. In addition, the infrared lamp can limit the processing portion by condensing the light with a mirror or the like, or can amplify the processing capability (heating temperature) by forming a spot light. Specifically, when the light is focused by a lamp of 100 V and 980 W, it is possible to heat up to 1200 ° C. at the spot portion. In addition, the rising speed is very fast, reaching 400 ° C. after 1 second, reaching 800 ° C. after 2 seconds, and reaching 1200 ° C. after 4 seconds.
Furthermore, these heating adjustments can be arbitrarily adjusted by electric power control, and there is an advantage that various feedback controls can be easily constructed by a system combined with an infrared sensor.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration example of the present apparatus.

FIG. 2 shows a diagram illustrating a cycle of generation and destruction of ozone.

FIG. 3 is a diagram showing an infrared absorption spectrum of 2,6-di-t-butyl-4-ethylphenol as an example of an infrared absorption spectrum of an organic compound.

FIG. 4 is a diagram showing an infrared absorption spectrum of butylhydroxytoluene as an example of an infrared absorption spectrum of an organic compound.

FIG. 5 is a diagram showing an infrared absorption spectrum of 4,4′-methylenebis (2,6-di-t-butylphenol) as an example of an infrared absorption spectrum of an organic compound.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Infrared lamp 2 Adhered matter 3 Film 4 Cast roll 5 T die

Claims (5)

[Claims] 1. An apparatus for removing deposits on a roll surface, which irradiates infrared rays to the surface of a roll for transporting a film and removes the deposits by heating. 2. The infrared light having a peak wavelength of 2.8 μm to 25 μm.
2. The apparatus for removing deposits on a roll surface according to claim 1, wherein the thickness is μm. 3. The apparatus for removing deposits on a roll surface according to claim 1, wherein a source of infrared rays is a halogen lamp. 4. A method for forming a film, comprising irradiating the surface of a roll for transporting the film with infrared rays, and forming the film while heating and removing attached matter. 5. The infrared light having a peak wavelength of 2.8 μm to 25.
5. The method according to claim 4, wherein the thickness is μm.