JP2003248397A - Method of measuring inorganic oxide and instrument for measuring inorganic oxide - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of measuring inorganic oxides capable of rapidly and exactly measuring an amount of the inorganic oxides on a recording medium under conditions equal to an actual printing state of electrostatic latent image developing toners and an instrument for measuring the inorganic oxides. <P>SOLUTION: The method of measuring the inorganic oxides by utilizing a photoreceptor and fixing roll used in an electrophotographic method and the instrument for measuring the inorganic oxides using the same include a process step of transferring the electrostatic latent image developing toners from the photoreceptor onto the recording medium, then measuring the amount of the inorganic oxides on the recording medium by a sensor while moving or stopping the recording medium and a process step of fixing the electrostatic latent image developing toners on the recording medium, then detecting the amount of contamination to the fixing roll by the inorganic oxides. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring an inorganic oxide and an apparatus for measuring an inorganic oxide, and more specifically, a toner for developing an electrostatic latent image (hereinafter may be simply referred to as a toner). The present invention relates to an inorganic oxide measuring method and an inorganic oxide measuring apparatus capable of quickly and accurately measuring the amount of inorganic oxide on a recording medium under the same conditions as in the actual printed state.

[0002]

2. Description of the Related Art In electrophotography and the like, toners used to form an electrostatic latent image into a visible image are generally thermoplastic resins (binder resins), waxes, charge control agents, magnetic powders, and the like. After premixing the additives of, the melt kneading step,
The toner having a desired particle size is manufactured through each of the crushing process and the classifying process. And
In the internal structure of the printer as shown in FIG. 8, the toner manufactured in this manner develops the electrostatic latent image on the photoconductor after a certain amount of electric charge is accumulated by frictional charging, and the desired visible image is obtained. It is used for imaging. Here, it is necessary that the electric charge accumulated in the toner by the triboelectric charging is either positive or negative depending on the type of the photoconductor on which the electrostatic latent image is formed. In addition, the amount of toner charged by frictional charging needs to be a sufficient amount to more accurately visualize an electrostatic latent image. Further, in recent years, as a photoconductive photoreceptor for forming an electrostatic latent image, it has no pollution and high sensitivity in place of a selenium photoreceptor or an organic photoconductive photoreceptor, and has a Vickers strength of 1, Amorphous silicon photoconductors (hereinafter sometimes referred to as a-Si photoconductors) are often used because they have characteristics of being extremely hard such as 500 to 2,000. Therefore, when developing an electrostatic latent image formed on such an a-Si photosensitive member, it is desired to use a toner excellent in charging property and durability.

Therefore, not only a charge control agent or a conductive substance is added to the binder resin, but also an inorganic oxide (such as silica, aluminum oxide, titanium oxide, zinc oxide) is added to the toner (or toner particles). Fine powder) is added externally to control the polarity of charge and the amount of charge, as well as the durability and the polishing property. However, when an inorganic oxide having a polarity opposite to that of the surface charge of the photoconductor is used, it develops in the non-latent image area on the surface of the photoconductor, and this is transferred to the recording paper through the transfer process, and the fixing roll is contaminated. There was a problem that caused. Further, even when an inorganic oxide having the same polarity as the surface charge of the photoconductor is used, when the number of printings increases, it shifts to a recording paper,
As a result, there was a problem that the fixing roll was contaminated. On the other hand, although it is known that such an inorganic oxide causes contamination of the fixing roll, no means for measuring the amount of the inorganic oxide on the recording paper has been found, let alone the arrangement of a sensor or the like. Due to the measurement method, no means has been found for measuring the amount of inorganic oxides on the recording paper in the actual printing state of the toner.

[0004]

The inventors of the present invention have, as a result of diligent study of the conventional problems, found that the toner transfer process by the photoconductor and the fixing roll used in the electrophotography and the specific sensor are used. The present invention has been completed by discovering that the inorganic oxide on the recording medium, which has been difficult to measure conventionally, can be measured quickly and accurately under the same conditions as the actual printing state of the toner, by combining the measurement step and It was made. That is, the object of the present invention is to
To provide an inorganic oxide measuring method and an inorganic oxide measuring apparatus capable of quickly and accurately measuring the amount of the inorganic oxide on the recording medium under the same conditions as the actual printed state of the toner. An object of the present invention is to provide a method for measuring an inorganic oxide and an apparatus for measuring an inorganic oxide, which can contribute to improvement of toner for developing an electrostatic latent image used in a photographic method.

[0005]

According to the present invention, there is provided a method for measuring an inorganic oxide using a photoconductor used in an electrophotographic method and a fixing roll, which is used for developing an electrostatic latent image from a photoconductor. After transferring the toner onto the recording medium, a step of measuring the amount of inorganic oxide on the recording medium with a sensor while moving or stopping the recording medium, and after fixing the electrostatic latent image developing toner on the recording medium, A method of measuring an inorganic oxide, comprising the step of detecting the amount of contamination of the fixing roll by the inorganic oxide is provided, and the above-mentioned problems can be solved. That is, a developing process using an electrophotographic method is constructed as a model, the amount of inorganic oxide on the recording medium in the state where the electrostatic latent image developing toner is transferred is measured by a sensor, and the amount of the inorganic oxide on the fixing roll is changed. Since the contamination is detected, there is no restriction on the arrangement of the sensor or the measuring method, and the amount of the inorganic oxide on the recording medium can be measured quickly and accurately in the actual printing state of the toner. In addition, by carrying out the method for measuring the inorganic oxide in this way, it becomes possible to predict the stain resistance to the fixing roll without checking the actual printing by the printing durability evaluation, and as a result, the fixing performance can be maintained for a long time. This will contribute to the development of a toner for electrostatic latent image development that can be stabilized over a period of time. When the recording medium is moved and measured by the sensor, the amount of the inorganic oxide can be measured in a state corresponding to the actual printing state because it is extremely close to the actual printing state. Further, when the recording medium is stopped and the amount of the inorganic oxide is measured, the printed portion and the non-printed portion can be clearly distinguished, so that the amount of the inorganic oxide on the recording medium can be measured more accurately.

Further, in carrying out the method for measuring an inorganic oxide of the present invention, a step of measuring the amount of the inorganic oxide after fixing the electrostatic latent image developing toner on the recording medium by the fixing roll with a sensor is further added. It is preferable to include.
By carrying out in this way, it is possible to quantitatively grasp the amount of the inorganic oxide that contaminates the fixing roll, and the correlation with the amount of the inorganic oxide on the recording medium in the state where the toner for developing the electrostatic latent image is transferred. Becomes clear. Therefore, it is possible to more accurately predict the contamination property of the fixing roll without performing confirmation by actual printing.

In carrying out the method for measuring an inorganic oxide according to the present invention, the amount of the inorganic oxide on the recording medium is determined by the fluorescent X
It is preferable to measure by a sensor using a line, for example, a fluorescent X-ray analyzer. By carrying out in this way, the amount of the inorganic oxide on the recording medium can be measured more rapidly and accurately. Further, since the fluorescent X-rays have excellent transparency, even inorganic oxides partially penetrating into the inside of the recording medium can be measured quickly and accurately.

In carrying out the method for measuring an inorganic oxide of the present invention, the amount of the inorganic oxide on the recording medium is 0 when the measured value when the inorganic oxide is measured alone is 100%. It is preferable to set the value within 0.005%. By carrying out in this manner, the contamination of the fixing roll can be effectively prevented, and the fixing performance of the toner by the fixing roll can be stabilized for a long period of time.

In carrying out the method for measuring an inorganic oxide according to the present invention, a free substance of an inorganic oxide externally added to a toner for developing an electrostatic latent image is measured as an inorganic oxide on a recording medium. Is preferred. By carrying out in this way, since the inorganic oxide which directly causes the contamination on the fixing roll is measured, the prediction of the contamination property on the fixing roll becomes more accurate.

In carrying out the method for measuring an inorganic oxide of the present invention, the fluorescent X-ray intensity of the inorganic oxide externally added to the toner for developing an electrostatic latent image is 50 to 5 when measured alone.
An inorganic oxide having a value within the range of 00 kcps is preferable. By carrying out in this way, the amount of inorganic oxides on the recording medium can be accurately measured by the fluorescent X-ray analyzer.

Further, in carrying out the method for measuring an inorganic oxide of the present invention, in measuring the amount of the inorganic oxide on the recording medium, the amount of the inorganic oxide in the recording medium without the electrostatic latent image developing toner being transferred is measured. It is preferable to standardize by subtracting (blank). By carrying out in this way, it is possible to eliminate the influence of the inorganic oxide contained in advance in the recording medium, and therefore the prediction of the stainability on the fixing roll becomes more accurate.

In carrying out the method for measuring an inorganic oxide according to the present invention, the error ratio of the amount of the inorganic oxide (blank) in the recording medium in a state where the toner for developing the electrostatic latent image is not transferred is a value within 10%. It is preferable that By carrying out in this way, it is possible to reduce the influence of the inorganic oxide contained in advance in the recording medium, so that the prediction of the stainability on the fixing roll becomes more accurate. That is, in normalizing and measuring the amount of inorganic oxides on the recording medium, not only when measuring the amount of inorganic oxides (blanks) contained in advance in the recording medium, but also the amount of inorganic oxides contained in advance in the recording medium (blank). It is possible to accurately standardize the amount of the inorganic oxide in the recording medium in the state where the toner for developing the electrostatic latent image is transferred, by estimating without actually measuring.

Further, in carrying out the method for measuring an inorganic oxide of the present invention, the surface potential of the photosensitive member when transferring the electrostatic latent image developing toner to the recording medium is set to a value within the range of 150 to 300V. It is preferable. If the surface potential of such a photoreceptor is not only equivalent to the actual printing conditions, but also as the electrostatic latent image developing toner, as a free substance of externally added particles,
The amount of the inorganic oxide transferred onto the recording medium can be set to a value within a certain range.

Another aspect of the present invention is an inorganic oxide measuring apparatus equipped with a photoconductor used for electrophotography and a fixing roll, wherein toner for developing an electrostatic latent image is transferred from the photoconductor. A drive unit for moving the recording medium in a closed state, and a sensor unit for measuring the amount of inorganic oxide on the recording medium,
An inorganic oxide measuring device, further comprising: a fixing roll for fixing the toner for developing an electrostatic latent image on a recording medium, and a detection unit for detecting the amount of inorganic oxide on the fixing roll. Is. With this configuration, there is no restriction on the arrangement of the sensor or the measuring method, and the amount of inorganic oxide on the recording medium in which the electrostatic latent image developing toner is transferred is measured by the sensor, and the inorganic oxide on the fixing roll is measured. It is possible to easily detect contamination by an object.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the method for measuring an inorganic oxide and the apparatus for measuring an inorganic oxide according to the present invention will be specifically described below with reference to the drawings.

[First Embodiment] A first embodiment is a method for measuring an inorganic oxide using a photoconductor used in an electrophotographic method and a fixing roll, and includes the following two steps (first step). 1 and 2 may be referred to respectively as the second step). (1) A step of transferring an electrostatic latent image developing toner from a photoconductor onto a recording medium and then measuring the amount of inorganic oxide on the recording medium by a sensor while moving or stopping the recording medium (2) On the recording medium After fixing the electrostatic latent image developing toner, detecting the amount of contamination of the fixing roll by the inorganic oxide

1. First Step (1) Sensor In the measuring device shown in FIGS. 1A and 1B, the type and configuration of the sensor used to measure the amount of inorganic oxide are not particularly limited, but for example, , Particle analyzer, UV analyzer, infrared analyzer,
A visible light analyzer, a fluorescent X-ray analyzer, a laser beam analyzer, etc. are mentioned. In particular, a fluorescent X-ray analysis including a fluorescent X-ray source 101, a vacuum pump 102, a sample chamber 103, a slit 104, a dispersive crystal 105, a detector 108, and a controller 109 as shown in FIG. When the apparatus 100 is used, not only the inorganic oxide attached to the surface of the recording medium but also the inorganic oxide that partially enters the recording medium can be measured quickly and accurately. Here, the sensor 6 of the measuring device shown in FIGS.
2 and 63, an X-ray fluorescence analyzer 1 as shown in FIG.
When 00 is used, the fluorescent X-ray intensity (kcps) attributed to the inorganic oxide on the recording medium before fixing is 0.005% with respect to the fluorescent X-ray intensity (kcps) of 100% of the inorganic oxide.
It is preferable to set the value within the range. The reason for this is that if the fluorescent X-ray intensity on the recording medium exceeds 0.005%, the fixing roll may be significantly contaminated and may be contaminated in a short time. However, if the fluorescent X-ray intensity (kcps) attributed to the inorganic oxide on the recording medium before fixing is excessively reduced, the actual printing efficiency may be significantly reduced.
Therefore, the fluorescent X-ray intensity (kcps) attributed to the inorganic oxide on the recording medium before fixing is 0.00001.
To 0.003% is more preferable, and a value within 0.00001 to 0.001% is further preferable. In measuring the fluorescent X-ray intensity of the inorganic oxide, it is preferable to supply power to the X-ray tube for generating X-rays at a voltage of 50 kV and a current of 50 mA, for example.

The relationship between the fluorescent X-ray intensity (%) attributed to the inorganic oxide on the recording medium and the contamination evaluation of the fixing roll will be described with reference to FIG. In FIG. 3, the horizontal axis shows the fluorescent X-ray intensity (%), and the vertical axis shows the numerical value of the contamination evaluation of the fixing roll. It should be noted that in quantifying the fouling property of the fixing roll, ◎ evaluation shown in Example 1 was set to 5 points, ∘ evaluation was set to 3 points, △ evaluation was set to 1 point, and × evaluation was set to 0 point. Is. As can be easily understood from the characteristic curve shown in FIG. 3, the higher the fluorescent X-ray intensity (%) attributed to the inorganic oxide on the recording medium, the more the contamination roll evaluation of the fixing roll tends to decrease. , 0.005%, there was a tendency that the evaluation of stain resistance of the fixing roll was significantly lowered. Conversely, if the fluorescent X-ray intensity (%) attributed to the inorganic oxide on the recording medium is a value within 0.005%, a relatively good evaluation of stain resistance of the fixing roll is obtained, and If the value is within 003%, a good fixing roll contamination evaluation is obtained,
Further, it has been found that when the value is within 0.001%, a remarkably good evaluation of stain resistance of the fixing roll can be obtained.

Further, when measuring the amount of inorganic oxide on the recording medium by the sensor, it is preferable to deduct and standardize the amount of inorganic oxide on the recording medium in a state where the toner for developing the electrostatic latent image is not transferred. That is, since the recording medium often contains an inorganic oxide such as titanium oxide in advance, the influence thereof is eliminated when the amount of the inorganic oxide on the recording medium is measured. More specifically, as shown in FIG. 4A, the recording medium 84 of a predetermined size is divided into two areas (A and B), and the electrostatic latent image developing toner is applied in the area A. Amount of inorganic oxide in the recording medium 81 without transfer (fluorescent X-ray intensity: A
1) is measured. Next, with the area A being masked, the electrostatic latent image developing toner 82 is transferred only to the area B,
In that state, the amount of inorganic oxide (fluorescent X-ray intensity: B1) in the non-printed portion of the B region is measured. Then, in comparison with the fluorescent X-ray intensity of the inorganic oxide alone, the amount of the inorganic oxide transferred from the photoconductor onto the recording medium 80 is accurately calculated from the fluorescent X-ray intensity of (B1-A1). .

Further, as shown in FIG. 4B, it is possible to prepare separate recording media 86 and 88 and measure the amount of the inorganic oxide transferred from the photoconductor onto the recording media. That is, in the recording medium 88 represented by A, the amount of inorganic oxide (fluorescent X
The line intensity: A1) is measured. Next, in another recording medium 86 represented by B, the amount of inorganic oxide (fluorescent X-ray intensity: B1) in the non-printed portion in the state where the electrostatic latent image developing toner 82 is transferred is measured. Then, the amount of the inorganic oxide transferred from the photoconductor onto the recording medium is accurately calculated from the fluorescent X-ray intensity of (B1-A1) in comparison with the fluorescent X-ray intensity of the inorganic oxide alone.

(2) Recording Medium Electrostatic Latent Image Developing Toner To measure the amount of inorganic oxide under actual printing conditions, a toner used in an electrophotographic method is used to transfer electrostatic latent image developing toner onto a recording medium. Is to be transferred. The details of the electrostatic latent image developing toner will be described later.

Transfer Conditions The transfer conditions of the toner for developing an electrostatic latent image from a photoconductor used in an electrophotographic method onto a recording medium are not particularly limited. For example, the surface potential of the photoconductor is 150.
It is preferable to set the value within the range of 500 V. The reason for this is that when the surface potential of the photoconductor becomes a value of less than 150 V, the transfer of the electrostatic latent image developing toner becomes insufficient,
This is because there is a case where the actual printing conditions are different from the actual printing conditions. on the other hand,
This is because when the surface potential of such a photoreceptor exceeds 300 V, the amount of the inorganic oxide transferred to the recording medium as a free substance of the externally added particles is significantly increased, which may cause remarkable contamination of the fixing roll. Therefore, the surface potential of the photoconductor is more preferably set to a value within the range of 180 to 400V, and further preferably set to a value within the range of 200 to 300V.

Here, the influence of the surface potential of the photoreceptor on the fluorescent X-ray intensity measured in the fluorescent X-ray measurement will be shown.
That is, the surface potential of the photoconductor is set to 250 V and 300 V, and the X-ray fluorescence analyzer 100 as shown in FIG.
Was used to measure the fluorescent X-ray intensity of each inorganic oxide contained in the recording medium. The results obtained are shown in Table 1.
As is clear from the results, in the measurement example of this inorganic oxide, it was confirmed that when the surface potential of the photoconductor was set to 250 V, about 60% of the fluorescent X-ray intensity was obtained when the surface potential was set to 300 V. Therefore, when measuring the fluorescent X-ray intensity of each inorganic oxide contained in the recording medium, the surface potential of the photoconductor is kept constant or the fluorescent X-ray intensity of the photoconductor is taken into consideration. It is preferable to modify the value. More specifically, by setting the surface potential of the photoconductor to ± 10%, the fouling property of the fixing roll can be accurately predicted, and by setting the surface potential of the photoconductor to ± 5%, the fixing roll is fixed. Can be more accurately predicted. On the other hand, the surface potential of the photoconductor is set to 250 V and 30
When the fluorescent X-ray intensity of each inorganic oxide is set to 0 V, and the measured value of the fluorescent X-ray intensity of 250 V is used as a reference, the measured value of the fluorescent X-ray intensity at 300 V is approximately 0.6 Multiply by the coefficient.

Table 1

Recording Medium The recording medium to which the toner for developing the electrostatic latent image is transferred is not particularly limited, and examples thereof include paper, coated paper, and plastic according to actual printing conditions. Further, the size thereof is not particularly limited, but B5, A5, B4, A4, B3, A3, B2, A2
It is preferable to use a standard product having the same size.
Further, it is preferable that the error ratio of the amount of the inorganic oxide (blank) in such a recording medium is a value within 10%. The reason for this is that by carrying out in this way, the influence of the inorganic oxides previously contained in the recording medium can be reduced, and the prediction of the staining property on the fixing roll becomes more accurate. That is, in normalizing and measuring the amount of inorganic oxides on the recording medium, not only when measuring the amount of inorganic oxides (blanks) contained in advance in the recording medium, but also the amount of inorganic oxides contained in advance in the recording medium (blank). This is because the amount of the inorganic oxide in the recording medium in the state where the toner for developing the electrostatic latent image is transferred can be accurately standardized by estimating without actually measuring.

Here, 10 sheets of paper 85 as shown in FIG. 5 are prepared, and the amount of inorganic oxide (blank) previously contained in the recording medium is measured by using the fluorescent X-ray analyzer 100 as shown in FIG. did. That is, in one sheet of paper 85 shown in FIG. 5, an area A and an area B indicated by dotted lines are arbitrarily assumed, and the fluorescent X-ray analyzer 100 is used to record the recording medium (A
The fluorescent X-ray intensity (blank) of the inorganic oxide contained in the region and the region B) was measured. The obtained results are shown in Table 2. As is clear from the result, in this measurement example, the in-plane error ratio of the amount of the inorganic oxide contained in advance in the recording medium was about 4
It was confirmed to be as small as%. Therefore, by using a recording medium in which the error ratio of the amount of in-plane inorganic oxide is small in this way, it is possible to reduce the influence of the inorganic oxide contained in advance in the recording medium, and to more accurately predict the fusing roll contamination. Becomes

Table 2

(3) Inorganic oxide The inorganic oxide to be measured in the first embodiment is
Titanium oxide, silica, zirconium oxide, aluminum oxide, zinc oxide and the like may be used alone or in combination of two or more. Further, titanium oxide is roughly classified into titanium oxide having an anatase type crystal structure and titanium oxide having a rutile type crystal structure, and the position of the absorption peak of the fluorescent X-ray is slightly different due to the difference in crystal structure. Both can be targeted, although they may differ.

Here, the influence of the type of the inorganic oxide on the fluorescent X-ray intensity measured using the fluorescent X-ray analyzer is shown. That is, two types of titanium oxide (X150: single fluorescent X-ray intensity 70 kcps, X113: single fluorescent X-ray intensity 183 kcps) are prepared, and a fluorescent X-ray analyzer 100 as shown in FIG. The respective fluorescent X-ray intensities contained in were measured. The results obtained are shown in Table 3. As is clear from the results, in this measurement example of the inorganic oxide, it was confirmed that the fluorescent X-ray intensity was about 2.5 times higher when X113 was used than when X150 was used.
Therefore, by using a part or all of the inorganic oxide capable of obtaining such a high fluorescent X-ray intensity in the toner for developing an electrostatic latent image, it is possible to more accurately predict the contamination property on the fixing roll.

Table 3

2. Second Step (1) Fixing Roll The structure of the fixing roll used in the first embodiment is not particularly limited, but while having a proper elasticity,
Silicone rubber, chloroprene rubber, NB because it can be heated and has excellent creep resistance
A rubber roller made of R rubber or the like is preferable. Further, it is preferable that the surface of these rubber rollers is subjected to a peeling treatment made of a fluororesin or a silicone resin. Further, it is preferable to provide a contact or non-contact type cleaning member according to the purpose of cleaning the fixing roll.

(2) Detection As long as the contamination of the fixing roll can be accurately detected,
It is preferable that the detection device has the same structure as the sensor for measuring the amount of the inorganic oxide in the recording medium, but it is also preferable that the detection is performed directly by a different structure such as weight measurement or concentration measurement. Further, as shown in Examples described later, since it is extremely simple, a direct visual inspection of the fixing roll may be performed. Further, in detecting the contamination of the fixing roll, it is preferable to further include a step of measuring the amount of the inorganic oxide after fixing the electrostatic latent image developing toner on the recording medium by the fixing roll with a sensor. That is, in the first step, not only the amount of inorganic oxide on the recording medium on which the electrostatic latent image developing toner is transferred is measured, but also in the second step, the electrostatic latent image developing toner is used. By measuring the amount of the inorganic oxide on the recording medium in which the toner is fixed, the amount of the inorganic oxide attached to the fixing roll can be quantitatively grasped. Therefore, it is possible to quantitatively grasp the fouling property of the fusing roll from the amount of the inorganic oxide attached to the fusing roll, and the fouling property of the fusing roll and the recording medium in the state in which the electrostatic latent image developing toner is transferred. The correlation with the above inorganic oxide amount becomes more accurate. Therefore, the contamination of the fixing roll can be more accurately predicted from the amount of the inorganic oxide on the recording medium in the state where the toner for developing the electrostatic latent image is transferred, without performing the actual print confirmation.

3. Toner used in the first embodiment is a toner particle composed of, for example, a binder resin, a wax, a charge control agent, and a magnetic powder according to actual conditions, except that an inorganic oxide is excluded. It is preferable that they are added together. Less than,
Each component will be described separately.

(1) Binder Resin The type of binder resin used in the toner used in the first embodiment is not particularly limited, but for example,
Styrene resin, acrylic resin, styrene-acrylic copolymer, polyethylene resin, polypropylene resin, vinyl chloride resin, polyester resin, polyamide resin, polyurethane resin, polyvinyl alcohol resin, vinyl ether resin, It is preferable to use a thermoplastic resin such as an N-vinyl resin or a styrene-butadiene resin.

The binder resin preferably has two weight average molecular weight peaks (a low molecular weight peak and a high molecular weight peak). Specifically, the low molecular weight peak is in the range of 3,000 to 20,000, and the other high molecular weight peak is 300,000 to 1,
It is preferably in the range of 50,000 and Mw / Mn of 10 or more. When the weight average molecular weight peak is within such a range, the toner can be easily fixed and the offset resistance can be improved.
The weight average molecular weight of the binder resin is determined by measuring the elution time from the column using a molecular weight measuring device (GPC) and comparing it with a calibration curve prepared in advance using a standard polystyrene resin. be able to.

In the binder resin, the softening point is preferably set to a value within the range of 110 to 150 ° C.,
It is more preferable to set the value within the range of 120 to 140 ° C. This is because the binder resin has a softening point of 11
This is because if the temperature is lower than 0 ° C., the obtained toners may be fused with each other and storage stability may be deteriorated. On the other hand, if the softening point of the binder resin exceeds 150 ° C., the fixability of the toner may be poor. The glass transition point (Tg) of the binder resin is preferably in the range of 55 to 70 ° C, more preferably 58 to 68 ° C. The reason for this is that if the glass transition point of the binder resin is less than 55 ° C., the obtained toner particles may be fused to each other and storage stability may decrease. On the other hand, if the glass transition point of the binder resin exceeds 70 ° C., the fixability of the toner may be poor. The softening point and glass transition point of the binder resin can be obtained from the endothermic peak position and the change point of the specific heat using a differential scanning calorimeter (DSC).

(2) Waxes In addition, it is preferable to add waxes in order to obtain the effect of fixing property and offset property in the toner. The type of such waxes is not particularly limited, but for example, polyethylene wax,
Examples thereof include polypropylene wax, fluorine-based wax, Fischer-Tropsch wax, paraffin wax, ester wax, montan wax, rice wax and the like, which may be used alone or in combination of two or more. When Fischer-Tropsch wax is used, it is more preferable that its weight average molecular weight is 1000 or more and that it has an endothermic bottom peak by DSC in the range of 100 to 120 ° C. As such a Fischer-Tropsch wax, Sazol wax C1 (high molecular weight grade by crystallization of H1 available from Sazol Co., endothermic bottom peak: 106.5) is used.
C), Sazol wax C105 (purified product of C1 by fractionation method, endothermic bottom peak: 102.1 ° C.), Sazol wax SPRAY (fine particles of C105, endothermic bottom peak: 102.1 ° C.) and the like. .

The amount of waxes added is not particularly limited, but for example, the total amount of toner is 1
The amount of waxes added is 1 to 5 when it is set to 00% by weight.
A value within the range of wt% is preferable. If the amount of waxes added is less than 1% by weight, offset to the reading head and image smearing tend not to be effectively prevented, while the amount of waxes added is 5% by weight.
If it exceeds, the toners will be fused to each other, and the storage stability tends to decrease.

(3) Charge control agent Further, in the toner, the charge level and the charge rising characteristic (an index of whether or not the toner is charged to a constant charge level in a short time).
It is preferable to add a charge control agent from the viewpoint that the property is remarkably improved and characteristics such as excellent durability and stability are obtained.
The type of such a charge control agent is not particularly limited, but for example, positive charge such as nigrosine, a quaternary ammonium salt compound, a resin type charge control agent in which an amine compound is bound to a resin, or the like is used. It is preferable to use a charge control agent having a property.

When the total amount of toner is 100% by weight, the amount of charge control agent added is 1.5 to 15% by weight.
It is preferable that the value is within the range. If the amount of the charge control agent added is less than 1.5% by weight, it becomes difficult to impart stable charging characteristics to the toner, and the image density tends to be low and the durability tends to be low. In addition, poor dispersion tends to occur, causing so-called fog, and the contamination of the photoconductor tends to become severe. On the other hand, if the addition amount of the charge control agent exceeds 15% by weight, environmental resistance,
In particular, poor charging and image failure under high temperature and high humidity tend to cause defects such as contamination of the photoconductor.

(4) Magnetic Powder In the toner, known magnetic powder can be dispersed in the toner to form a magnetic toner. The preferred magnetic powder is a metal or alloy exhibiting ferromagnetism such as ferrite, magnetite, iron, cobalt, nickel, etc., or a compound containing these ferromagnetic elements, or an appropriate heat treatment containing no ferromagnetic elements. An alloy or the like which exhibits ferromagnetism can be given. The average particle size of the magnetic powder is preferably in the range of 0.1 to 1 μm, more preferably in the range of 0.1 to 0.5 μm. The reason is that the magnetic powder having such an average particle size is easy to handle, but can be uniformly dispersed in the toner binder in the form of fine powder. Further, it is preferable that the surface of the magnetic powder is surface-treated with a surface treatment agent such as a titanium coupling agent or a silane coupling agent. This is because such surface treatment can improve the hygroscopicity and dispersibility of the magnetic powder.

(5) Externally added particle toner includes titanium oxide, silica, zirconium oxide,
It is preferable to add externally added particles such as aluminum oxide and zinc oxide. Further, it is also preferable that these externally added particles are surface-treated with colloidal silica, hydrophobic silica or the like for the purpose of improving the fluidity and storage stability of the toner. In addition, in the toner, the release rate of the inorganic oxide measured by using a particle analyzer is 10.0%.
It is preferable that the value is within the range. The reason for this is that if the liberation rate exceeds 10.0%, the amount of the inorganic oxide present alone increases, and is not held on the toner surface. Therefore, the inorganic oxide is likely to be developed on the photoreceptor, and as a result, the amount of the inorganic oxide on the recording medium before fixing may increase. Also,
The addition amount of the externally added particles is preferably set to a value within the range of 0.5 to 15% by weight based on the total amount. The reason for this is
This is because if the added amount of the externally added particles is less than 0.5% by weight, the effect of improving the charging property and the flow property of the toner may not be exhibited, while the added amount of the externally added particles is 15% or less. This is because if the content exceeds 5% by weight, the liberated externally added particles may easily contaminate the fixing roll. Therefore, the amount of the externally added particles added is more preferably within the range of 1 to 10% by weight, and even more preferably within the range of 2 to 7% by weight, based on the total amount.

On the other hand, in order to suppress or prevent the contamination of the fixing roll, it is preferable to reduce the liberation rate of the externally added particles. That is, if the externally added particles are not detached from the toner particles and remain attached, the fixing roll is less likely to be contaminated. Here, the relationship between the fluorescent X-ray intensity (%) attributed to the inorganic oxide on the recording medium and the liberation rate of the externally added particles will be described with reference to FIG. Figure 6
Shows the fluorescent X-ray intensity (%) on the horizontal axis, and shows the liberation rate of externally added particles on the vertical axis.
As can be easily understood from the characteristic curve shown in FIG. 6, the higher the fluorescent X-ray intensity (%) attributed to the inorganic oxide on the recording medium, the higher the liberation rate of the externally added particles, which is almost the same. It is understood that there is a proportional correlation. Conversely,
It is understood that if the liberation rate of the externally added particles is low, the fluorescent X-ray intensity (%) attributed to the inorganic oxide on the recording medium is also low, and the fouling property of the fixing roll is low, which is good. .

(6) Average Particle Size Although the average particle size of the toner is not particularly limited, it is preferably set to a value within the range of 5 to 12 μm, for example. The reason is that the average particle size of the toner is 5 μm.
This is because when the value is less than 1, the charging property and the flow property of the toner may be deteriorated, and further, the liberation rate of the externally added particles may be increased. On the other hand, when the average particle size of the toner exceeds 12 μm, This is because the liquidity of may decrease. Therefore, the average particle diameter of the toner is 6 to 11 μm.
It is more preferable to set the value within the range of 7 to 10 μm
It is more preferable to set the value within the range.

[Second Embodiment] A second embodiment is an inorganic oxide measuring apparatus equipped with a photoconductor used for electrophotography and a fixing roll, for developing an electrostatic latent image from the photoconductor. A drive unit for moving the recording medium on which the toner is transferred, and a first unit for measuring the amount of inorganic oxide on the recording medium.
Of the inorganic latent image, the fixing unit for fixing the electrostatic latent image developing toner on the recording medium, and the detecting unit for detecting the amount of the inorganic oxide on the fixing roll. It is an oxide measuring device. Hereinafter, the contents already described in the first embodiment will be omitted, and different points will be described as the second embodiment.

1. The drive unit is a unit for moving the recording medium on which the electrostatic latent image developing toner is transferred from the photoconductor toward the detection unit, and is composed of a drive roll, a belt conveyor, or the like. Preferably there is. For example, in the inorganic oxide measuring apparatus shown in FIG. 1, the driving roll 68 is the main constituent element of the driving unit. Further, when the contact pressure of the drive roll 68 or the like on the photoconductor becomes excessively high, the amount of toner for developing the electrostatic latent image transferred from the photoconductor may change. Therefore, the contact pressure is preferably such that the recording medium can be stably fed at a constant speed.

2. Sensor part The sensor part is a part for measuring the amount of inorganic oxide on the recording medium before fixing, and is preferably composed of, for example, a fluorescent X-ray analyzer or its probe.
The number of such fluorescent X-ray analyzers or their probes is not particularly limited, but at least one or more, more preferably, a value within the range of 2 to 5 is preferable.

The amount of the inorganic oxide on the recording medium is shown in FIG.
As shown in (a) and (b), it is preferable to measure with sensors 62 and 63 provided on one side or both sides of the recording medium 60. For example, as shown in FIG. 1A, when the measurement is performed by the sensor 62 provided on one side of the recording medium 60, there is an advantage that there are less restrictions on the arrangement of the sensor and the measuring method. On the other hand, as shown in FIG. 1B, when the measurement is performed by the plurality of sensors 62 and 63 provided on both sides of the recording medium 60, the amount of the inorganic oxide on the recording medium 60 can be measured from both sides. It is possible to measure more quickly and accurately.

Further, a sensor (may be a probe)
As shown in FIGS. 1 (a) and 1 (b), it is preferable that the installation position is between the photoconductor 66 and the fixing rolls 70 and 72, and the installation position is movable. That is, the line W shown in FIGS. 1 (a) and 1 (b)
It is preferable to move the sensors 62 and 63 in the horizontal direction within the range. With this configuration, the photoconductor 6
Even when the size and the arrangement of the fixing roller 70 and the fixing rolls 70 and 72 are changed, or when the moving speed of the recording medium 60 is changed, the movable sensors 62 and 63 allow the inorganic oxidation on the recording medium 60. This is because the physical quantity can be measured quickly and accurately. Further, if the sensors 62 and 63 can also be moved in synchronization with the moving speed of the recording medium 60, the amount of the inorganic oxide on the recording medium 60 can be measured more accurately. Note that the distance (W) between the photoconductor 66 and the fixing rolls 70 and 72 is set to a value within a range of 1 to 500 cm so that measurement, installation of the sensor, and movement of the sensor can be facilitated by the sensor. Is preferable, the value within the range of 5 to 300 cm is more preferable, and the value within the range of 20 to 100 cm is more preferable. Although not shown, it is preferable that a driving device for the sensor unit is provided so that the position of the sensor unit can be moved. For example, a rail may be arranged along the moving path of the recording medium, and a table with a bearing for fixing the sensor may be arranged on the rail.

3. Fixing Unit The fixing unit is a unit for heating and pressing the electrostatic latent image developing toner transferred on the recording medium to fix the toner on the recording medium. For example, it is preferable that the fixing unit mainly includes the rubber roller as described above.
Further, when the fixing unit is excessively contaminated, the correlation between the amount of inorganic oxide measured by the sensor unit and the fouling property of the fixing roller may be broken. Therefore, a cleaning unit may be provided in the fixing unit. preferable. As an example, in the inorganic oxide measuring apparatus shown in FIG. 1, a contact type cleaning blade 74 is provided.

[0051]

The present invention will be described in more detail based on the following examples. Needless to say, the following description exemplifies the present invention, and the scope of the present invention is not limited to the following description without any particular reason.

[Example 1] 1. Preparation of Toner (1) Preparation of Toner Particles Styrene / acrylic resin, polyethylene wax, charge control agent, and magnetic powder were melt-kneaded in a twin-screw extruder so as to have the following mixing ratio, and the mixture was prepared. Obtained. The total amount of styrene / acrylic resin, polyethylene wax, and charge control agent was 100 parts by weight. Next, after cooling the obtained mixture, a pulverizing step and a classifying step were performed to obtain toner particles having an average particle diameter of 7 μm. Styrene / acrylic resin 96 parts by weight Polyethylene wax 3 parts by weight Charge control agent 1 part by weight Magnetic powder 40 parts by weight

(2) Addition of Externally Added Particles With respect to 100 parts by weight of the obtained toner particles, titanium oxide and silica particles (SiO ₂ ) are added as externally added particles in the following mixing ratio.
And, respectively. Then, the mixture was further mixed to deposit titanium oxide or the like on the surface to prepare a toner. Toner particles 100 parts by weight Titanium oxide 1 part by weight Silica particles (SiO ₂ ) 0.5 parts by weight

2. Evaluation of Toner The obtained toner is constituted as a magnetic one-component developer, and a
-Page printer made by Kyocera equipped with Si photoconductor (FS-18
The contamination of the fixing roll was evaluated using the photoreceptor of (00) and the fixing roll.

(1) Measurement of the amount of inorganic oxide on the recording medium As shown in Table 4, the inorganic oxide on the recording medium before fixing was changed by changing the liberation rate and type of the inorganic oxide in the toner or the charging potential of the photoconductor. Fluorescent X-ray intensity (kcp) attributed to oxide
The ratio of s) was changed. That is, with the fluorescent X-ray analyzer, the fluorescent X-ray intensity (kcps) of titanium oxide alone
X-ray intensity (kcp) attributed to the inorganic oxide on the recording medium before fixing in each toner when
s) was measured. It should be noted that FIG. 7A shows a measurement chart of the fluorescent X-ray intensity of the recording medium before transferring the toner, and FIG. 7B shows the fluorescent X-ray intensity of the recording medium after transferring the toner. The measurement chart of is shown. On each chart, the horizontal axis shows the peak angle, and the corresponding fluorescent X-ray intensity (kcps) is shown. The height of the peak at a peak angle of 86.12 degrees corresponds to the amount of inorganic oxide.
The difference between the peak intensities shown in (a) and FIG. 7 (b) is
The amount of inorganic oxide in the non-printed portion of the recording medium after transferring the toner is shown.

(2) Evaluation of Contamination Property on Fixing Roll Toners having different release rates of inorganic oxides and the like are constituted as magnetic one-component developers, and a page printer (FS-1800) manufactured by Kyocera equipped with a-Si photoconductor is used. , Normal environment (20 ℃,
At 65% RH), a continuous printing test of 3,000 sheets was performed. After that, the fixing roll was visually observed, and the contamination property of the fixing roll was evaluated. A: No contamination of the fixing roll is observed. A: Slight contamination of the fixing roll is recognized. Δ: Slight contamination of the fixing roll is observed. X: Remarkable fusing roll contamination is observed.

(3) Release Rate of Inorganic Oxide In addition, a particle analyzer PT-100 (manufactured by Yokogawa Electric Co., Ltd.) was used to select some of the obtained toners to determine the release rate of inorganic oxide. It was measured. The results obtained are shown in Table 4. Here, the liberation rate of the inorganic oxide is defined as the total titanium count number counted as titanium oxide is A,
When the asynchronous titanium count number counted by titanium oxide alone is B, it can be calculated from the following calculation formula. Release rate (%) = (B / A) × 100

Table 4

[0059]

According to the method for measuring an inorganic oxide and the apparatus for measuring an inorganic oxide using the same according to the present invention, even if the actual printing state of the toner for developing an electrostatic latent image is equivalent to that on the recording medium. It has become possible to rapidly and accurately measure the above inorganic oxides. Therefore, based on the measurement results, by controlling the type of the external additive processing agent for the electrostatic latent image developing toner and the surface potential of the photoconductor in the direction of suppressing the amount of inorganic oxides on the recording medium, It has become possible to effectively prevent contamination of the fixing roller for a long period of time without using a cleaning member substantially. Further, according to the inorganic oxide measuring method of the present invention and the inorganic oxide measuring apparatus using the same, based on the obtained measurement results, there is little contamination on the fixing roller, and the fixing performance is long-term. It has become possible to contribute to the development of electrostatic latent image developing toner that can be stabilized.

[0060]

[Brief description of drawings]

FIG. 1 is a diagram provided for explaining an inorganic oxide measuring apparatus of the present invention.

FIG. 2 is a diagram showing an example of a fluorescent X-ray analyzer.

FIG. 3 is a characteristic diagram showing the relationship between the fluorescent X-ray intensity (%) representing the amount of inorganic oxide on the recording medium in the electrostatic latent image developing toner and the evaluation result of the fixing roll.

FIG. 4 is a diagram provided for explaining a method for measuring an inorganic oxide of the present invention.

FIG. 5 is a diagram provided for explaining a recording medium in the method for measuring an inorganic oxide of the present invention.

FIG. 6 is a characteristic showing the relationship between the fluorescent X-ray intensity (%) representing the amount of inorganic oxide on the recording medium in the electrostatic latent image developing toner and the liberation rate of externally added particles in the electrostatic latent image developing toner. It is a figure.

FIG. 7A is a measurement chart of fluorescent X-ray intensity of an inorganic oxide in a recording medium before transfer of toner.
(B) is a measurement chart of the fluorescent X-ray intensity of the inorganic oxide in the recording medium after the toner is transferred.

FIG. 8 is a diagram provided for explaining the internal structure of the printer.

[0061]

[Explanation of symbols]

1: Image forming apparatus 2: Polygon mirror 5: Optical transmission mechanism 7: Upper door 9: Photoreceptor 10: Developing device 31: Toner container 32: developing roller 33: Supply roller 39: Toner sensor 47: Display 60: recording medium 66: Photoreceptor in inorganic oxide measuring device 68: Driving roll for measuring device of inorganic oxide 62, 63: sensor 70, 72: fixing roll 74: Cleaning blade 101: X-ray fluorescence source in X-ray fluorescence analyzer 108: Detector in X-ray fluorescence analyzer

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yukinori Nakayama             704 No. Matabei, Noshino, Tamaki Town, Tokai District, Mie Prefecture             19 Kyocera Corporation Mie Factory Tamaki Block             Within F term (reference) 2G001 AA01 BA04 CA01 FA02 FA09                       GA09 GA11 JA02 KA01 LA20                       NA20                 2H005 AA08 CB07 CB13 EA10                 2H033 BA60 BB01 CA01                 2H134 QA01

Claims (10)

[Claims] 1. A method for measuring an inorganic oxide using a photoconductor used in an electrophotographic method and a fixing roll, wherein after the electrostatic latent image developing toner is transferred from the photoconductor onto a recording medium, the recording is performed. A step of measuring the amount of inorganic oxides on the recording medium with a sensor while moving or stopping the medium, and after fixing the electrostatic latent image developing toner on the recording medium, detecting the amount of contamination of the fixing roll by the inorganic oxides. Process,
A method for measuring an inorganic oxide, which comprises: 2. The inorganic material according to claim 1, further comprising the step of measuring the amount of inorganic oxide after fixing the electrostatic latent image developing toner on a recording medium with a fixing roll by a sensor. Oxide measurement method. 3. The method for measuring an inorganic oxide according to claim 1, wherein the amount of the inorganic oxide on the recording medium is measured by a sensor using fluorescent X-rays. 4. The amount of the inorganic oxide on the recording medium is set to a value within 0.005% when the measured value when the simple substance of the inorganic oxide is measured is 100%. The method for measuring an inorganic oxide according to claim 1. 5. The free substance of inorganic oxide externally added to the electrostatic latent image developing toner is measured as the inorganic oxide on the recording medium. The method for measuring an inorganic oxide according to the item 1. 6. An inorganic oxide externally added to the toner for developing an electrostatic latent image has a fluorescent X-ray intensity of 50 to 50 measured by itself.
The method for measuring an inorganic oxide according to claim 5, wherein the inorganic oxide has a value within a range of 500 kcps. 7. When measuring the amount of inorganic oxide on the recording medium, the amount of inorganic oxide on the recording medium in a state where the toner for developing an electrostatic latent image is not transferred is subtracted and standardized. 7. The method for measuring an inorganic oxide according to any one of 1 to 6. 8. The error ratio of the amount of inorganic oxide in the recording medium in a state where the toner for developing the electrostatic latent image is not transferred is 1.
The method for measuring the inorganic oxide according to claim 1, wherein the value is within 0%. 9. The surface potential of the photoreceptor when transferring the electrostatic latent image developing toner onto a recording medium is set to a value within a range of 150 to 300V. The method for measuring an inorganic oxide according to the item 1. 10. In an inorganic oxide measuring device provided with a photoconductor used for electrophotography and a fixing roll, the recording medium in which the electrostatic latent image developing toner is transferred from the photoconductor is moved. A drive unit, a sensor unit for measuring the amount of inorganic oxides on the recording medium, a fixing roll for fixing the toner for electrostatic latent image development on the recording medium, and the amount of inorganic oxides on the fixing roll. And a detector for the purpose of measuring the inorganic oxide.