JPH1076563A - Method of manufacturing film for heat fixing material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a film having a good surface condition and having a suitable balance between a linear expansion coefficient, an elastic modulus and a tear propagation resistance and suitable as a heat fixing material. SOLUTION: Using an extruder, 90 to 50% by weight of polyallyl ether ketone and 10 to 5% of inorganic filler are used.
A resin composition containing 0% by weight is kneaded and melted at 350 to 420 ° C., extruded from a die while being filtered through a filter having a filtration diameter of 10 to 80 μm, and has a surface temperature of 200 to 2 μm.
Cool with a cooling roll controlled at 50 ° C. to a thickness of 10 to 1
A method for producing a film for a heat-fixing material, which comprises shaping the film into a 00 μm film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a film for a heat fixing material. Specifically, the present invention relates to a method for producing a film for a heat-fixing material obtained from polyallyl ether ketone containing an inorganic filler, which has a good surface condition and a suitable balance between a linear expansion coefficient, an elastic modulus and a tear propagation resistance. The present invention relates to a method for producing a film suitable as a material.

[0002]

2. Description of the Related Art Conventionally, as a heat fixing means provided in a printer, a copying machine, or the like, a heat fixing roller having a heating member at an inner central shaft portion and a pressure roller which is in pressure contact with the heat fixing roller are provided. A method has been adopted in which the unfixed toner is passed through paper or a plastic film to which the unfixed toner has been transferred, and the unfixed toner is melted and fixed by heat and pressure. However, since the heat capacity of the heat fixing roll is large, it takes several minutes for the temperature of the surface of the heat fixing roll to reach a predetermined temperature after the energization of the heating element, and the printing standby time is long. there were. In addition, there is a problem in terms of energy saving, for example, it is necessary to always heat the heat fixing roll in order to shorten the waiting time.

In recent years, fixing means using heat-resistant resin of an energy-saving type, which transmits heat energy efficiently, has a short waiting time, and has been put to practical use. This fixing means has a structure having a heat-resistant film in the form of a tube or a belt which rotates with a paper or a plastic film on which an unfixed toner as a heated body is transferred in contact with the heated body. The time from when the heating element is energized to when the surface of the fixing film reaches a predetermined temperature can be greatly reduced, and there is no need to constantly heat the fixing film, so that power consumption is small. The heat-resistant film used for the heat fixing device that heats and melts the toner on the paper or plastic film, which is the object to be heated, from the heating element through the heat-resistant film as described above, is currently made of a thermosetting polyimide resin in a tubular shape. Shaped ones are used.

Further, a thin-walled tube containing a heat conductive filler has been adopted for the purpose of improving the heat conductivity. For example, JP-A-7-110632 discloses an inner layer formed of a resin composition containing a heat-resistant resin and an insulating inorganic filler having an average particle size of 0.5 to 15 μm, and contains a fluororesin and a conductive filler. A fixing belt having a three-layer structure of an outer layer formed of a resin composition, and an intermediate layer formed of a resin composition containing a resin having an adhesive property to both the inner layer and the outer layer and a conductive filler is disclosed. I have. In this gazette, as the heat-resistant resin forming the inner layer, polyimide and polyamide imide are preferable, and as a preferred embodiment, polyimide that cannot be melt-molded is employed, and a polyimide film is formed from a polyimide varnish by a solution casting method. Is disclosed. However, the fixing belt not only has a drawback that the polyimide layer of the base material contains a small amount of organic solvent, but also requires a solvent removal step in the manufacturing method, so that the process becomes longer, and the productivity is increased due to batch processing. Is bad.

[0005] As means for improving these problems,
There has been proposed a method of forming into a tube shape by extrusion molding of a thermoplastic resin. For example, Japanese Unexamined Patent Publication No. 7-199691
Japanese Patent Application Publication No. JP-A-2003-133873 discloses a fixing belt formed by extruding a thermoplastic polyimide, polyetherimide (PEI), polyethersulfone (PES), polyetheretherketone (PEEK), polyphenylene sulfide (PPS) or the like into a tube. I have. However, these fixing belts and the like do not have sufficient heat resistance, and have a drawback that the tubes are wrinkled in an actual machine test.

That is, amorphous PES, PEI, etc.
The glass transition temperature is about 220 ° C. at the maximum.
Since the temperature may be as high as about 50 ° C., wrinkles may occur in the film forming the heat fixing roll, the fixing belt, and the like,
This will disturb the image. Crystalline PPS, PEEK, etc. have a glass transition temperature of about 90 ° C. for PPS and about 15 ° C. for PEEK.
When the extruded tube is used as it is because it is as low as 0 ° C,
Above the glass transition temperature, the modulus of elasticity decreases and deforms.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a heat-fixing resin which can be formed into a tube by fusion bonding, has a good surface condition, and has an appropriate balance of linear expansion coefficient, elastic modulus and tear propagation resistance. An object of the present invention is to provide a method for producing a film suitable as a material.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to achieve the above object, and as a result, a specific amount of an inorganic filler has been uniformly dispersed in polyallyl ether ketone and molded under specific molding conditions. The resulting film has excellent heat resistance and surface condition, high elastic modulus at high temperature, low linear expansion coefficient, excellent tear propagation resistance, and their properties are appropriately balanced. The present inventors have found that the material is suitable for a heat fixing material, and have reached the present invention.

That is, the present invention uses an extruder to prepare a resin composition containing 10 to 50% by weight of an inorganic filler with respect to 90 to 50% by weight of a polyallyl ether ketone.
Kneaded and melted at 0-420 ° C, filtration diameter 10-80
Extrude from the die while filtering through a μm filter,
A method for producing a film for a heat fixing material, wherein the film is cooled by a cooling roll having a surface temperature controlled at 200 to 250 ° C. to form a film having a thickness of 10 to 100 μm.

The film for a heat fixing material obtained by the present invention contains a specific amount of an inorganic filler, and its properties in a machine direction or a direction perpendicular to the machine direction are (1)
The coefficient of linear expansion at 25 to 250 ° C. is 1 × 10 ⁻⁵ to 4 ×
10 ^-5 / ° C, (2) The elastic modulus at 200 ° C is 0.1 to
5 GPa, and (3) tear propagation resistance is 200-
1500 g / mm, they are moderately balanced. Therefore, it is excellent not only in heat resistance but also in dimensional stability and strength at high temperatures. In addition, since it is a thermoplastic film, it can be easily formed into a tube by heat fusion or the like. Therefore, it is extremely useful as a method for producing a film used as a heat fixing material such as a heat fixing roll installed in a printing machine, a copying machine, or the like.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates to the production of a film for a heat-fixing material in which a specific amount of an inorganic filler is added to and mixed with polyallyl ether ketone, and the mixture is molded under specific conditions using an extruder. Is the way. Hereinafter, the present invention will be described in detail.

The polyallyl ether ketone used in the present invention has the formula (1)

[0013]

Embedded image , Formula (2)

[0014]

Embedded image And formula (3)

[0015]

Embedded image And polyallyl ether ketone having a repeating structural unit represented by

Examples of the polyallyl ether ketone having a repeating structural unit represented by the above formula (1) include polyether ether ketone (hereinafter, referred to as PEEK). Examples of commercially available products include “Victrex-PEEK” (trade name, manufactured by ICI, UK). Examples of those having a repeating structural unit represented by the above formula (2) include polyether ketone (hereinafter, referred to as PEK). As a commercially available product, for example, there is a product name “Victrex-PEK” manufactured by ICI UK. Examples of those having a repeating structural unit represented by the above formula (3) include polyether ketone ether ketone ketone (hereinafter, referred to as PEKEKK). As a commercially available product, for example, trade name “Ultra” manufactured by BASF, Germany
pek ”and the like. These may be used alone or as a mixture of two or more.

As the inorganic filler used in the present invention, for example, spherical fillers such as boron nitride, aluminum nitride, silicon nitride, silicon carbide, magnesia, silica, alumina, zirconia, beryllium oxide, glass fiber, aluminum borate whisker, etc. Needle filler,
Further, plate-like fillers such as glass flakes and mica are exemplified. When needle-like fillers are used, the extruded film tends to have anisotropy in the mechanical properties of the resulting film because the fillers are oriented in the direction of film flow, but the direction of temperature distribution and load during use should be taken into consideration. By adjusting the direction of the film, performance equal to or higher than that of the spherical filler can be obtained.

When the shape of the inorganic filler is spherical, the average particle size affects the dispersibility in the polymer, the uniformity of the obtained film composition, and the like. If the average particle size is too fine or too coarse, the dispersibility in the polymer will decrease. From such a viewpoint, the average particle size is preferably from 0.1 to 10 μm. More preferably, it is 0.5 to 5 μm. In the case of a needle shape, the aspect ratio (the ratio between the length and the diameter of the needle) is 10 to 10.
It is preferably 0. If it is too large, it will be damaged by shearing during film formation such as extrusion, and if it is too small, effects such as a decrease in linear expansion coefficient will be reduced. In the case of a plate-like filler, the length of the longest piece of the plate is preferably 0.1 to 10 μm in consideration of dispersibility in a polymer.

The content of the inorganic filler is 10 to 50% by weight, preferably 20 to 40% by weight. If it is less than 10% by weight, the effect of improving the elastic modulus at high temperatures is not sufficient,
When used as a substrate for a heat fixing roller or the like, when used at a high temperature, a tube or the like may be wrinkled, which is not preferable. On the other hand, when the content exceeds 50% by weight, the lip opening degree is usually 0.5 when producing a film having a thickness of 10 to 100 μm.
When the thickness is set to about 1 mm, the draft ratio is large, so that there is a problem such as generation of pinholes during take-off. For example, even if a film is obtained, the tear strength is significantly reduced, and when formed into a tube or the like and attached to a heat fixing device, if the tube meanders, a problem such as cracking of the end face occurs, which is not preferable.

Next, the method of the present invention will be described. The above-mentioned polyallyl ether ketone powder or pulverized powder and an inorganic filler are mixed using a mixer such as a Henschel mixer, a universal mixer, a ribbon blender or the like, and the obtained mixture is mixed using a twin-screw kneading extruder.
A method in which pellets are formed at 30 ° C. to 400 ° C., and the pellets are kneaded and melted using a melt extrusion molding machine or the like, extruded from a T-die or the like, and then cooled using a cooling roll or the like to form a film. , A polyallyl ether ketone pellet and a master batch of a polyallyl ether ketone pellet containing a high concentration of inorganic filler are mixed by a mixer such as a ribbon blender at a ratio that results in the content of the inorganic filler, and a melt extrusion molding machine or the like is used. A method of kneading, melting, extruding from a T-die or the like, and shaping into a film in the same manner as above is exemplified.

In consideration of the dispersibility of the inorganic filler, the inorganic filler is preferably mixed with a powder. The temperature of the extruder during film formation is preferably from 350 to 420 ° C. When the temperature of the extruder is lower than this range, the melt viscosity of the resin is too high, and the pressure in the narrow flow path such as the filter or T-die rises abnormally, and the extruder motor is overloaded, resulting in extrusion. May be disabled. In addition, if the temperature is higher than this range, gelation of the resin occurs, and if the temperature is higher, the resin is decomposed,
Not only is the surface condition of the film worsened by the occurrence of so-called bumps or uneven flow called fish eyes,
As the molding time elapses, the viscosity increases and the load increases, and extrusion molding tends to become impossible.

In addition, removal of contaminated foreign substances and so-called gel-like substances which have stayed in the extruder for a long time and have a high molecular weight, further improve the dispersibility of the inorganic filler, or prevent the appearance of the film from being poor due to the aggregation of the filler. For this purpose, it is preferable to install a cylindrical or disk-shaped filter having a filtration diameter (opening) of 10 to 80 μm between the tip of the cylinder of the extruder and a T-die or the like.
If the filtration diameter (opening) of the filter is smaller than 10 μm, the pressure rise of the resin in the extruder becomes large, and the motor is overloaded, so that the extruder may not be able to be formed. If it is larger than 80 μm, so-called gel-like substances are removed,
The effect of improving the dispersibility of the filler is reduced. The filter is filtered to improve the dispersibility of the filler, and the resulting film does not show fish eyes such as foreign matters, gels, or filler agglomerates on the surface of the resulting film. When it is molded into a heat fixing device and used, it causes poor contact with the object to be heated due to the protrusion, resulting in poor fixing.
The image is not disturbed.

The film discharged from a T-die or the like has a surface temperature of 200 to 250 ° C., preferably 210 to 230 ° C.
It cools and solidifies using a cooling roll controlled at a temperature of ° C. and shapes it into a film. Polyallyl ether ketone is about 23
Outside of this range, the crystallization rate of the polyallyl ether ketone is slow and the crystallization is incomplete because the maximum value of the crystallization rate is exhibited around 0 ° C., and the obtained film has a glass transition temperature of about 150 ° C. or higher. In this case, the elastic modulus sharply decreases and the heat resistance becomes poor.

The film for a heat fixing material produced by the method of the present invention is formed into, for example, a tube, a belt or the like to be a heat fixing base material. Although there is no particular limitation on the method of forming the film into a tube or the like, after the film is rolled into a cylindrical shape, it is set in a cylindrical mold that can be heated and pressed, and then the entire surface or only the connecting portion is heated to, for example, 350 to 430 ° C. A simple method such as a method of press-fitting and setting in a cylindrical mold, and a method of fusing the connecting portion using ultrasonic waves can be applied.

When it is desired to further improve the heat resistance of the film for a heat fixing material obtained by the present invention, the film is formed into a tube or the like and then cooled at a temperature not lower than the cooling temperature at the time of film formation, for example, 250 ° C. to 300 ° C. The heat treatment is preferably performed for 120 minutes. The thickness of the film for a heat fixing material obtained by the present invention is usually 10 to 100 μm.

The thermal expansion material film (in the machine direction or in a direction perpendicular to the machine direction) obtained as described above according to the present invention has a linear expansion coefficient of 1 × in the temperature range of 25 to 250 ° C. by the TMA method. It is 10 ^-5 to 4 × 10 ^-5 / ° C. Further, the elastic modulus at 200 ° C. is 0.1 to 5 GP.
a, and the tear propagation resistance is 200 to 1500 g / mm.

Therefore, even when considering that the temperature of a heater such as a heat fixing roll of a printer reaches a maximum of about 250 ° C., the film for a heat fixing material obtained by the present invention can sufficiently withstand it. Has heat resistance. Further, if the linear expansion coefficient in the temperature range of 25 to 250 ° C. exceeds 4 × 10 ⁻⁵ / ° C., for example, in the case of a heat fixing film of a printer, when a paper or the like to be heated is carried over the entire surface of the heater, When paper or the like having almost the same temperature but different sizes is carried in (partial paper passing), the temperature of the portion where the object to be heated does not exist becomes higher than the temperature of the portion where the object is present, and the temperature difference of up to about 80 ° C. Will occur,
A wrinkle due to a difference in linear expansion occurs, causing a fixing failure and disturbing an image.

In this case, if the elastic modulus of the film is low, the film is likely to be deformed and wrinkled.
The elastic modulus at 0 ° C. needs to be 0.1 GPa or more.
Furthermore, when the tubular film moves left and right during rotation, a phenomenon occurs in which the ends collide with metal or the like. At this time, if the tear propagation resistance of the film is not 200 g / mm or more, cracks are generated from the ends, and the cracks grow to the inner side, which again disturbs the image.

As described above, the film for a heat-fixing material obtained by the present invention can be used as a heat-fixing roll of a high-speed, energy-saving printer and a copying machine, and can further reduce the cost. is there.

[0030]

The present invention will be described in more detail with reference to the following examples. The methods for measuring the characteristic values of the films for heat fixing materials described in the examples and comparative examples are described below.

(1) Coefficient of linear expansion (° C. ⁻¹ ) Using a TMA / SS-120 type device manufactured by Seiko Electronics Co., Ltd., elongation is performed at a temperature rising rate of 5 ° C./min, a load of 3 g, and a load of 25 g under nitrogen atmosphere. The coefficient of linear expansion is calculated from the elongation of the film in the temperature range of ２５０250 ° C. The sample size is 20 mm in length and 3 mm in width.

(2) Modulus of elasticity (GPa) Tensilon / UTM-4-1 manufactured by Toyo Baldwin Co., Ltd.
Using a 00 type tensile tester and a thermostat for tensile tester (Toyo Baldwin / TLF-4-40-B), sample size 10 mm x 200 mm, distance between grips 100 m
m at 200 ° C. at a test speed of 5 mm / min.

(3) Tearing Propagation Resistance (g / mm) Measured by the method A (trouser test) specified in JIS-K7128. The test speed is 200 mm / min.

(4) Surface accuracy (pieces) The entire surface of a square sample having a side of 30 cm was observed using a loupe (magnification: 25 times), and the number of projecting fish eyes having a size of 0.2 mm or more was determined. Measure.

Example 1 "Victrex PEEK-380P" 70 manufactured by ICI
% By weight and 30% by weight of aluminum nitride (manufactured by Mitsui Toatsu Chemicals, Inc., trade name: MAN-2) were mixed with a Henschel mixer, kneaded and melted at 330 to 350 ° C. using a twin screw extruder. And extruded to form pellets. The obtained pellets are fed into a 50 mm diameter single screw extruder (forming temperature 4 mm).
00 ° C.), passed through a leaf disk type filter having a filtration diameter (opening) of 20 μm attached between the tip of the extruder cylinder and the front of the T die, and extruded from a 1100 mm wide T die. Cooling, solidifying and shaping with a cooling roll (φ400 mm) at 220 ° C.
A μm film for heat fixing material was obtained. Type of polyallyl ether ketone used, type and amount of inorganic filler added, extrusion molding conditions [temperature, filter filtration diameter (open),
[Cooling roll surface temperature] is shown in [Table 1]. The linear expansion coefficient, elastic modulus, tear propagation resistance, and surface accuracy of the obtained film for a heat fixing material were measured by the above-mentioned methods, and the results are shown in [Table 1].

Examples 2 to 6 and Comparative Examples 1 to 8 Types of polyallyl ether ketone used, types and amounts of inorganic fillers used, extrusion molding conditions [temperature, filter filtration diameter (opening), cooling roll surface temperature] Was changed in the same manner as in Example 1 except that the thickness was changed as described in [Table 1].
A 0 μm film for a heat fixing material was obtained. The amount of polyallyl ether ketone added in each example was an amount (% by weight) that became 100% by weight in total with the amount of inorganic filler added. The PEK used in Example 2 was ICI
(Trade name: Victrex PEK-220P, PEKEKK used in Example 3 was manufactured by BASF, trade name: Ultrapek-A1000, aluminum borate whisker used in Example 4 was Shikoku Chemical Industry Co., Ltd.) Manufactured and trade name: Arbolex Y. The linear expansion coefficient, elastic modulus, tear propagation resistance and surface accuracy of the film for heat fixing material obtained in each example were measured in the same manner as in Example 1, and the results are shown in [Table 1].

[0037]

[Table 1]

<Consideration of Examples> All of the films obtained in Examples 1 to 6 have a linear expansion coefficient of 1 × 10 ⁻⁵ to 4 × 10 ⁻⁵ / ° C. in a temperature range of 25 to 250 ° C., and 200 ° C
Has a modulus of 0.1 to 5 GPa and a tear propagation resistance of 200 to 1500 g / mm. Therefore, the film for a heat fixing material obtained therefrom is extremely useful as a heat fixing material.

On the other hand, in the film obtained in Comparative Example 1, the effect of the filler mixing was insufficient because the amount of the inorganic filler was too small, the coefficient of linear expansion was too large, and the film for the heat fixing material was insufficient. It became something. On the contrary, the film obtained in Comparative Example 2 had a tear propagation resistance of less than 200 g / mm because the amount of the inorganic filler was too large.
Cracks may occur during practical use, and it is impossible to use the film as a heat fixing material film.

In Comparative Example 3, since the extrusion temperature was low, the melt viscosity of the resin was high, and the motor of the extruder was overloaded, the rotation of the screw was stopped, and extrusion was impossible. Comparative Example 4
Extrusion was possible because the extrusion temperature was too high,
Many gels were present on the surface of the obtained film. Also, two hours after the start of the extrusion, the motor of the extruder was overloaded, the rotation of the screw was stopped, and the extrusion became impossible. Since the obtained film has a rough surface, image defects due to uneven fixing may occur, so that it cannot be used as a film material for a heat fixing material.

In Comparative Example 5, since the filtration diameter of the filter was too small, the pressure rapidly increased, the motor of the extruder was overloaded, the rotation of the screw was stopped, and extrusion was impossible. In Comparative Example 6, on the contrary, the filtration diameter of the filter was too large, so that extrusion was possible. However, aggregates and gels of the filler were present on the surface of the obtained film, which became surface defects of the film and became heat fixing materials. It is impossible to use as a film for use.

In Comparative Example 7, since the cooling roll temperature was 200 ° C. or less, the coefficient of linear expansion of the obtained film was 180 °.
The temperature rose rapidly above ℃, and the dimensional stability deteriorated. In Comparative Example 8, since the surface temperature of the cooling roll was too high, the obtained film had a large linear expansion coefficient and a low elastic modulus at 200 ° C. Therefore, the films obtained in both cases cannot be used as heat fixing film materials.

[0043]

According to the method of the present invention, a heat-fixing material having excellent heat resistance, mechanical properties, and dimensional stability, having a good surface condition, and a moderately balanced linear expansion coefficient, elastic modulus, and tear propagation resistance. Film is obtained. The film is
It can be suitably used as a material for heat fixing such as a heat fixing roll of a high-speed, energy-saving printer, a copying machine or the like.

Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical indication location C08L 29/12 C08L 29/12 G03G 15/20 101 G03G 15/20 101 // B29L 7:00 (72) Invention Yukihiro Kumamoto 2-1-1 Tango-dori, Minami-ku, Nagoya-shi, Aichi Mitsui Toatsu Chemicals Co., Ltd.

Claims (4)

[Claims] 1. An inorganic filler of 10 to 5% by weight based on 90% to 50% by weight of polyallyl ether ketone using an extruder.
A resin composition containing 0% by weight is kneaded and melted at 350 to 420 ° C., extruded from a die while being filtered through a filter having a filtration diameter of 10 to 80 μm, and has a surface temperature of 200 to 2 μm.
Cool with a cooling roll controlled at 50 ° C. to a thickness of 10 to 1
A method for producing a film for a heat-fixing material, which comprises shaping the film into a 00 μm film. 2. The polyallyl ether ketone of the formula (1)
[Chemical 1] [Chemical 1] , Formula (2) [Formula 2] And formula (3) The method for producing a film for a heat-fixing material according to claim 1, comprising at least one type of repeating structural unit represented by the following formula: 3. An inorganic filler having an average particle size of 0.1 to 1
0 μm spherical inorganic filler, aspect ratio 5-100
Needle-shaped inorganic filler and the length of the longest side is 0.1-10μ
2. The method for producing a film for a heat-fixing material according to claim 1, wherein the film is at least one kind of inorganic filler selected from m plate-like inorganic fillers. 4. The heat fixing material film in a machine direction or a direction perpendicular to the machine direction, (1) 25 to 25.
The linear expansion coefficient at 0 ° C. is 1 × 10 ⁻⁵ to 4 × 10 ⁻⁵ /
° C, (2) The elastic modulus at 200 ° C is 0.1 to 5 GP.
a, (3) The method for producing a film for a heat fixing material according to any one of claims 1 to 3, wherein the tear propagation resistance is 200 to 1500 g / mm.