JP2017105869A - Method for producing silicone rubber molding body and method for producing image formation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrences of volatile organic compounds and ultrafine particles.SOLUTION: A method for producing a silicone rubber molding body comprises step S1 for immersing a silicone rubber molding body in organic solvent A for treatment, and step S2 for immersing the silicone rubber molding body in organic solvent B different in solubility parameter from the organic solvent A for treatment.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a method for manufacturing a silicone rubber molded body, and more particularly to a method for manufacturing a silicone rubber molded body used for a silicone rubber roller of an image forming apparatus.

  By using a printer, a copier, a facsimile machine, or a combination of these, volatile organic compounds (VOC) such as low molecular weight siloxane and ultra fine particles (UFP) with a particle diameter of less than 100 nm are discharged. This has been pointed out in the past, and in recent years the amount of emission has been regulated.

Studies have been conducted to suppress the generation of volatile organic compounds.
For example, Patent Document 1 proposes reducing the low-molecular siloxane by vacuum heat treatment after molding silicone rubber, and also proposes solvent extraction before and after the vacuum heat treatment (claims 1, 8, paragraph 0012). -0014, 0022-0023, 0024-0025, etc.).
In Patent Document 2, a proposal is made to remove the cyclic dimethylpolysiloxane and low-molecular-weight dimethylpolysiloxane remaining in the silicone rubber product by immersing them in an organic solvent having a close solubility coefficient and a low boiling point and subjecting them to ultrasonic treatment. (See claim 1, page 4, lower right column, line 11 to end of same run, page 6, lower right column, line 13 to page 7, lower left column, line 6; see FIG. 3).
Patent Document 3 proposes that a silicone rubber molded body is immersed in an organic solvent having a solubility parameter of more than 9.3 and not more than 15.0 and a boiling point of not less than 50 ° C. and not more than 90 ° C. to reduce the low molecular weight of organopolysiloxane. (See claim 1, paragraphs 0008 to 0009, 0017 to 0019, etc.). In particular, in the technique of Patent Document 3, the technique of Patent Document 2 is used, and an organic solvent having a slightly higher solubility parameter than that of a silicone rubber molded body is used to reduce low-molecular siloxane while suppressing swelling of the molded body ( (See paragraph 0017 etc.).

JP-A-6-25431 JP-A-1-36627 JP 2005-139394 A

However, with the technique of Patent Document 1, it is difficult to completely remove low molecular weight siloxane only by vacuum heat treatment.
Regarding the technique of Patent Document 2, it is effective to remove the low-molecular siloxane on the surface of the roller by immersing in an organic solvent having a close solubility coefficient. However, this technology is insufficient to remove the low molecular siloxane remaining inside the silicone rubber, and the remaining low molecular siloxane is heated at the time of fixing and diffuses over time. The problem that becomes a source of generation of ultrafine particles is remarkable.
Regarding the technique of Patent Document 3, only an organic solvent having a relatively large solubility parameter and a slightly low compatibility with silicone rubber has a weak ability to dissolve low-molecular-weight siloxane and cannot exhibit a sufficient reduction effect.
Therefore, the main object of the present invention is to provide a method for producing a molded silicone rubber that can suppress the generation of volatile organic compounds and ultrafine particles.

In order to solve the above problems, according to the present invention,
Immersing the silicone rubber molding with the first organic solvent;
Immersing the silicone rubber molded body with a second organic solvent having a solubility parameter different from that of the first organic solvent;
A method for producing a silicone rubber molding is provided.

  According to the present invention, generation of volatile organic compounds and ultrafine particles can be suppressed.

1 is a diagram illustrating a schematic configuration of an image forming apparatus. It is a figure which shows schematic structure of a fixing roller (pressure roller). It is a flowchart which shows the manufacturing method of a silicone rubber molded object over time. It is a figure which shows one aspect | mode for applying a physical pressure to a silicone rubber molding. It is a figure which shows the other aspect for applying a physical pressure to a silicone rubber molding. It is a flowchart which shows the modification of the manufacturing method of a silicone rubber molding. 3 is a flowchart illustrating a method for manufacturing an image forming apparatus over time.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
In the following, “to” indicating a numerical range is used in a sense that upper and lower limits described before and after the numerical range are included in the numerical range.

[Image forming apparatus]
FIG. 1 shows a schematic configuration of a color tandem type image forming apparatus 100 according to a preferred embodiment of the present invention. This image forming apparatus is a multifunction machine having functions such as a scanner, a copy, and a printer, and is called an MFP (Multi Function Peripheral or Multi Function Printer).

As shown in FIG. 1, the image forming apparatus 100 includes an annular intermediate transfer belt 108 that moves in the circumferential direction and is wound around two rollers 102 and 106 at the approximate center in the main body casing 101.
Of the two rollers 102 and 106, one roller 102 is disposed on the left side in the figure, and the other roller 106 is disposed on the right side in the figure. The intermediate transfer belt 108 is supported by these rollers 102 and 106 and is driven to rotate in the arrow X direction.

  Below the intermediate transfer belt 108, image forming units 110Y, 110M, 110C, and 110K corresponding to yellow (Y), magenta (M), cyan (C), and black (K) toners in order from the left in the drawing. Are arranged side by side.

The image forming units 110Y, 110M, 110C, and 110K are configured in the same manner except for the difference in toner colors that they handle.
For example, the yellow image forming unit 110 </ b> Y includes a photosensitive drum 190, a charging device 191, an exposure device 192, a developing device 193 that performs development using toner, and a cleaner device 195. .
A primary transfer roller 194 is provided at a position facing the photosensitive drum 190 with the intermediate transfer belt 108 interposed therebetween.
At the time of image formation, the surface of the photosensitive drum 190 is first uniformly charged by the charging device 191, and then the surface of the photosensitive drum 190 is exposed by the exposure device 192 to form a latent image there. Next, the latent image on the surface of the photosensitive drum 190 is developed by the developing device 193 to become a toner image. This toner image is transferred to the intermediate transfer belt 108 by applying a voltage between the photosensitive drum 190 and the primary transfer roller 194. Transfer residual toner on the surface of the photosensitive drum 190 is cleaned by a cleaner device 195.

  As the intermediate transfer belt 108 moves in the arrow X direction, four color toner images are formed as an output image on the intermediate transfer belt 108 by the image forming units 110Y, 110M, 110C, and 110K.

On the left side of the intermediate transfer belt 108, a cleaning device 125 that removes residual toner from the surface of the intermediate transfer belt 108 and a toner collection box 126 that collects the toner removed by the cleaning device 125 are provided.
A secondary transfer roller 112 is provided on the right side of the intermediate transfer belt 108 with a conveyance path 124 for paper interposed therebetween. A transport roller 120 is provided in a position corresponding to the upstream side of the secondary transfer roller 112 in the transport path 124. An optical density sensor 115 for detecting a toner pattern on the intermediate transfer belt 108 is provided.

A fixing device 130 for fixing the toner to the sheet is provided at the upper right portion in the main body casing 101.
The fixing device 130 includes a pair of fixing rollers extending perpendicularly to the paper surface in FIG. One of the fixing rollers is a heating roller 132, and the other is a pressure roller 131.
The heating roller 132 is heated to a predetermined target temperature (for example, a fixing temperature in the range of 180 to 200 ° C.) by the heater 133. The pressure roller 131 is urged toward the heating roller 132 by a spring (not shown). Thereby, the pressure roller 131 and the heating roller 132 form a nip portion for fixing.
The sheet 90 on which the toner image has been transferred passes through the nip portion, whereby the toner image is fixed on the sheet 90. The temperatures of the pressure roller 131 and the heating roller 132 are detected by temperature sensors 135 and 136, respectively.

Under the main body casing 101, paper feed cassettes 116A and 116B for storing paper 90 are provided in two stages. FIG. 1 shows a state in which the sheet 90 is stored only in the sheet feeding cassette 116A.
Each of the paper feed cassettes 116A and 116B is provided with a paper feed roller 118 for feeding the paper and a paper feed sensor 117 for detecting the fed paper.

  In the main body casing 101, a control unit 200 including a CPU (Central Processing Unit) that controls the operation of the entire image forming apparatus is provided.

At the time of image formation, the paper 90 is fed one by one from the paper feed cassette 116A to the transport path 124 by the paper feed roller 118 under the control of the control unit 200. The sheet 90 sent to the transport path 124 is sent to the toner transfer position between the intermediate transfer belt 108 and the secondary transfer roller 112 by the transport roller 120 at a timing by the registration sensor 114.
On the other hand, as described above, the four color toner images are formed on the intermediate transfer belt 108 by the respective image forming units 110Y, 110M, 110C, and 110K, and are formed on the sheet 90 fed to the toner transfer position. The four color toner images on the transfer belt 108 are transferred by the secondary transfer roller 112.
The sheet 90 on which the toner image has been transferred is conveyed through a nip formed by the pressure roller 131 and the heating roller 132 of the fixing device 130 and is heated and pressurized. As a result, the toner image is fixed on the sheet 90.
Finally, the sheet 90 on which the toner image is fixed is discharged by a discharge roller 121 through a discharge path 127 to a discharge tray portion 122 provided on the upper surface of the main body casing 101.
Note that the image forming apparatus 100 is provided with a switchback conveyance path 128 for sending the paper sheet 90 to the toner transfer position again in the case of duplex printing.

[Fixing roller (pressure roller)]
As described above, the pressure roller 131 constitutes one of the fixing rollers, and here is a silicone rubber roller.
As shown in FIG. 2, the pressure roller 131 is mainly composed of a cylindrical silicone rubber molded body 10.
The silicone rubber molding 10 includes a cylindrical metal core 12, a solid rubber layer 14 provided so as to cover the outer peripheral surface of the metal core 12, and sponge rubber provided so as to cover the outer peripheral surface of the solid rubber layer 14. It has a three-layer structure with the layer 16. The solid rubber layer 14 and the sponge rubber layer 16 are made of silicone rubber. Here, a roller main body (a three-layer structure of the core metal 12, the solid rubber layer 14, and the sponge rubber layer 16) including this is molded into a silicone rubber. The name is 10. The silicone rubber molded body 10 is an example of a silicone rubber molded body according to the present invention.

The cored bar 12 is made of a metal material such as aluminum, iron, or SUS.
The thickness of the cored bar 12 is about 0.1 to 5 mm here, but is more preferably about 0.1 to 1.5 mm in view of weight reduction and warm-up time.
The diameter of the cored bar 12 is set to about 10 to 50 mm here.

The solid rubber layer 14 and the sponge rubber layer 16 are made of silicone rubber as described above.
Silicone rubber has heat resistance to the fixing temperature and elasticity to ensure the size of the area where the paper 90 is pressed (the length of the nip portion).
The solid rubber layer 14 is a solid hard layer. The thickness of the solid rubber layer 14 is preferably in the range of 5 to 10 mm, and is set to about 7 to 8 mm here.
On the other hand, the sponge rubber layer 16 is a sponge-like soft layer containing an infinite number of microballoons. The thickness of the sponge rubber layer 16 is desirably in the range of 5 to 100 μm, and is set to about 80 to 90 μm here.

[Manufacturing method of silicone rubber molding]
Then, the manufacturing method of the silicone rubber molding 10 is demonstrated.
This manufacturing method is basically a method of cleaning the silicone rubber molded body 10 immediately after the solid rubber layer 14 and the sponge rubber layer 16 are formed on the core metal 10, and is the final manufacturing process of the silicone rubber molded body 10. This assumes processing performed in stages.

As shown in FIG. 3, the manufacturing method of the silicone rubber molded body 10 is mainly
(I) Step S1 of immersing the silicone rubber molded body 10 with the organic solvent A;
(Ii) Step S2 of immersing the silicone rubber molded body 10 with an organic solvent B having a solubility parameter different from that of the organic solvent A.

(1) About organic solvents A and B The organic solvents A and B preferably satisfy the following conditions in order to efficiently wash and reduce the content of low-molecular siloxane.
That is, the solubility parameter of silicone rubber is around 7.3 to 7.6.
It is preferable that the solubility parameter of the organic solvent A is closer to the solubility parameter of the organic solvent B than the solubility parameter of the organic solvent A, and the solubility parameter of the organic solvent B is away from the solubility parameter of the organic solvent A.
Specifically, the difference in solubility parameter between silicone rubber and organic solvent A is 0 or more and less than 2.0, and the difference in solubility parameter between silicone rubber and organic solvent B is 2.0 or more and less than 7.3. More preferably, the difference in solubility parameter between the organic solvent A and the organic solvent B is 0.1 or more and 5.4 or less.

The “solubility parameter (SP value)” is an index indicating the polarity of a substance, and is a value indicating an affinity between substances.
The closer the solubility parameter between the low-molecular siloxane and the organic solvent is, the easier the organic solvent enters between the molecules of the low-molecular siloxane, and the easier the extraction of the low-molecular siloxane and the higher the cleaning effect.
The solubility parameter of low molecular siloxane is about 7.3 to 7.6.
In contrast, when the difference in solubility parameter between the low molecular siloxane and the organic solvent A is less than 2.0 and the solubility parameter of the organic solvent A is close to the solubility parameter of the low molecular siloxane, the volume expansion coefficient is large and the cleaning effect is enhanced. Further, when heated to the vicinity of the boiling point, the solubility of the low molecular siloxane also increases, and the cleaning effect is further enhanced.
Examples of the organic solvent A that satisfies such conditions include n-hexane, n-octane, cyclohexane, ethyl acetate, benzene, toluene, xylene, methyl ethyl ketone, and chloroform.
As the organic solvent A, n-hexane, cyclohexane, toluene, and xylene are preferably used, and n-hexane and toluene are preferable because they are easy to handle.
The organic solvent A may be used alone, or two or more kinds may be mixed and used.

The difference in solubility parameter between the low molecular siloxane and the organic solvent B is preferably 2.0 or more and less than 7.3.
The use of the organic solvent B is for the purpose of diffusing and washing the organic solvent A in which the low-molecular-weight siloxane is dissolved from the inside of the silicone rubber, and the organic solvent B is a solvent that is easily miscible with the organic solvent A and easily volatilizes. Is preferred.
Examples of the organic solvent B include isopropyl alcohol, methanol, ethanol, acetone, and methylene chloride.
The organic solvent B may be used alone, or two or more kinds may be mixed and used.
If the organic solvent B remains in the silicone rubber, a stable image cannot be produced when the silicone rubber molding 10 is used as a component of the image forming apparatus 100, and unevenness may occur. Preferably it is low. Therefore, the boiling point of the organic solvent A is preferably 35 ° C. or higher and 140 ° C. or lower, and the boiling point of the organic solvent B is preferably 35 ° C. or higher and 80 ° C. or lower.

(2) About immersion treatment process S1, S2 Preferably, in immersion treatment process S1, S2, the process of immersion treatment process S1 is performed first, and the process of immersion treatment process S2 is performed after that.
Particularly in the immersion treatment step S1, when the silicone rubber molded body 10 is immersed in the organic solvent A, the silicone rubber molded body 10 absorbs the organic solvent A and swells.
In such a case, it is effective that the absorption amount of the organic solvent A is 20 to 200% of the unit weight of the silicone rubber molded body 10 before the immersion treatment, preferably 30 to 200%, more preferably 40 to 200%. Is more effective.
That is, in the immersion treatment step S1, when the weight change of the silicone molded body 10 before and after the immersion treatment with the organic solvent A is measured, the weight of the silicone rubber molded body 10 after the immersion treatment is the same as that before the immersion treatment. It is effective to perform the dipping treatment so that the weight is 120 to 300%, preferably 130 to 300%, more preferably 140 to 300%, based on the weight of the silicone rubber molded body 10.
It should be noted that the immersion treatment steps S1 and S2 may be replaced after each other, or the immersion treatment step S2 may be performed first, followed by the immersion treatment step S1.

Although the immersion time (cleaning time) in the organic solvents A and B depends on the thickness of the solid rubber layer 14 and the sponge rubber layer 16 of the silicone rubber molding 10, it is preferable to immerse for 30 to 60 minutes.
It is more desirable to perform a rinsing step with new organic solvents A and B after washing.
In addition, it is desirable to perform a drying process in order to remove the organic solvents A and B remaining in the silicone rubber after washing or after the rinsing process, whether or not the rinsing process is performed. The drying step is preferably performed in an environment of 50 to 130 ° C. for 10 minutes to 3 hours, depending on the thickness of the solid rubber layer 14 and the sponge rubber layer 16 of the silicone rubber molded body 10.

(3) Heat treatment In the immersion treatment steps S1 and S2, the organic solvents A and B may be heated depending on the situation.
For example, when the immersion treatment is desired to be performed in a short time or when a higher cleaning effect is required, the organic solvents A and B may be heated.
The range of the heating temperature is desirably room temperature or higher and lower than the boiling point of the organic solvents A and B.
The heat treatment is preferably executed in both the immersion treatment steps S1 and S2, but may be executed only in the immersion treatment step S1, or may be executed only in the immersion treatment step S2.

(4) Ultrasonic Treatment In the immersion treatment steps S <b> 1 and S <b> 2, ultrasonic waves may be oscillated with respect to the silicone rubber molded body 10.
The oscillation time of the ultrasonic wave can be appropriately selected depending on the thickness and shape of the solid rubber layer 14 and the sponge rubber layer 16 of the silicone rubber molded body 10. For example, if a silicone rubber product having an average thickness exceeding 3 mm is swelled as described above, the oscillation time of the ultrasonic wave is more than 15 minutes. If a silicone rubber product having an average thickness of 3 mm or less is swelled as described above, the ultrasonic oscillation time is preferably 5 to 15 minutes, more preferably 5 to 10 minutes. By adjusting the ultrasonic wave oscillation time to such a range, the productivity can be uneven, or the low molecular weight siloxane can be removed to a desired residual amount.
The ultrasonic oscillation device is not particularly limited, but for example, the device described in Patent Document 2 can be suitably used. The frequency of the ultrasonic wave is not particularly limited, but usually about 40 kHz is employed industrially.
The ultrasonic oscillation process is preferably executed in both the immersion treatment steps S1 and S2, but may be executed only in the immersion treatment step S1, or may be executed only in the immersion treatment step S2.

In the immersion treatment steps S1 and S2, ultrasonic waves may be oscillated with respect to the silicone rubber molded body 10 while heating the organic solvents A and B, and the heating treatment and the ultrasonic oscillation treatment may be performed simultaneously. .
Even in such a case, the heat treatment and the ultrasonic oscillation treatment are preferably performed in both the immersion treatment steps S1 and S2, but may be performed only in the immersion treatment step S1, or only in the immersion treatment step S2. May be.

(5) Physical Pressure In the immersion treatment step S2, physical pressure may be applied to the silicone rubber molded body 10. The physical pressure is applied to the molded silicone rubber 10 immersed in the organic solvent B and pulled up from the organic solvent B.
For example, as shown in FIG. 4, the silicone rubber molded body 10 is forcibly passed through a metal squeezing ring 20 having a slightly smaller diameter, and physical pressure is applied to the silicone rubber molded body 10. As shown in FIG. 5, physical pressure may be applied to the silicone rubber molded body 10 by rotating the pressure roller 30 while being pressed against the silicone rubber molded body 10.

(6) About repetition of immersion treatment process S1, S2 In the manufacturing method of the silicone rubber molding 10, you may repeat immersion treatment process S1, S2 several times alternately.
That is, as shown in FIG. 6, the immersion treatment steps S1 and S2 may be set as one set (set S3) and the set S3 may be repeated two or more sets.
In the set S3, any of the immersion treatment steps S1 and S2 may be executed first, but in the sets S3, the immersion treatment steps S1 and S2 should be matched in advance. S1->S2->S1->...>S2->S1-> S2, or S2->S1->S2->...->S1->S2-> S1.
It is preferable that the immersion treatment steps S1 and S2 using the organic solvents A and B having a low boiling point between the organic solvent A and the organic solvent B are the final steps. This is because it is easy to remove the organic solvents A and B, and promptly proceeds to the next step (manufacture of the pressure roller 131 and installation in the image forming apparatus 100, see FIG. 7).

(7) About vacuum heating process As shown in FIG. 6, after repeating immersion process S1 and S2 several times alternately, you may provide process S4 which heats and drys the silicone rubber molding 10 under vacuum pressure reduction.
In the vacuum heat treatment S4, for example, a device such as a vacuum oven is used.
Although the vacuum heating conditions are not particularly limited, it is preferable that the degree of vacuum is 10 mmHg or less, the heating temperature is 100 to 250 ° C., and the treatment time is 1 to 25 hours.
The vacuum heating step S4 may not be performed after the repetition of the set S3, and may be provided after the immersion treatment steps S1 and S2 in FIG.

[Method for Manufacturing Image Forming Apparatus]
Next, a method for manufacturing the image forming apparatus 100 will be described.
This manufacturing method is basically a method in which the pressure roller 131 is manufactured using the cleaned silicone rubber molded body 10 and installed in the image forming apparatus 100, and the final assembly of the image forming apparatus 100 is performed. Is assumed.

As shown in FIG. 7, the manufacturing method of the image forming apparatus 100 is mainly as follows.
(I) Step S10 of manufacturing the pressure roller 131 using the silicone rubber molded body 10 manufactured by the method of FIGS.
(Ii) a step S20 of setting the pressure roller 131 at a predetermined position of the image forming apparatus 100.
In particular, in the manufacturing step S10 of the pressure roller 131, the surface of the silicone rubber molded body 10 may be polished or the silicone rubber molded body 10 may be cut into a predetermined length.

According to the above embodiment, in the immersion treatment step S1, the silicone rubber molded body 10 is immersed and swollen with the organic solvent A having a solubility parameter close to that of the silicone rubber, and remains on the surface of the silicone rubber molded body 10. The low molecular weight siloxane is removed.
In the immersion treatment step S2, the silicone rubber molding 10 is shrunk with an organic solvent B having a solubility parameter away from the silicone rubber, and the low molecular siloxane remaining inside the silicone rubber molding 10 is physically squeezed and removed. ing.
In this embodiment, the action on the silicone rubber molded body 10 is slightly different in each of the immersion treatment steps S1 and S2, and the low molecular siloxane is removed from both the surface and the inside of the silicone molded body 10.
Such an action can suppress the generation of volatile organic compounds and ultrafine particles.
In such a case, volatile organic compounds and ultrafine particles drifting inside the image forming apparatus 100 are also reduced, and generation of coarse particles that grow from the volatile organic compound can be suppressed, and as a result, occurrence of image contamination can be prevented. Can do.

In the conventional method, a method of cleaning with an organic solvent having a solubility parameter close to that of silicone rubber (see Patent Document 2), a method of cleaning with an organic solvent having a solubility parameter that is different from that of silicone rubber, and the silicone rubber does not swell (Patent Document 2) Document 3) has been proposed.
With the former method alone, since the solubility parameter is close between the silicone rubber and the organic solvent, the cleaning effect is high. However, when the concentration of the low molecular weight siloxane that dissolves in the organic solvent reaches saturation, it cannot be further cleaned. With the former method alone, even if this is repeated and washed with a fresh organic solvent constantly, the silicone rubber does not deform (swell and shrink), so the organic solvent does not move smoothly, and the silicone rubber does not move inside. The remaining low-molecular siloxane cannot be dissolved. On the other hand, even with the latter method alone, since the solubility parameter is different between the silicone rubber and the organic solvent, the cleaning effect is low and a sufficient cleaning effect cannot be obtained.

In this regard, according to the present embodiment, the organic solvent A that has permeated and swelled into the silicone rubber is squeezed by physical deformation by shrinking the silicone rubber using the organic solvent B that does not swell the silicone rubber. The low molecular weight siloxane remaining inside the silicone rubber is also washed away.
In addition, if the organic solvent A is newly washed with a high cleaning efficiency, the organic rubber A can always be washed by infiltrating the inside of the silicone rubber, and the low-molecular siloxane remaining in the silicone rubber can be further removed. It can be washed out well, and if the physical pressure is positively applied to the silicone rubber swollen with the organic solvent A and the organic solvent A is squeezed out, it can be washed better.

(1) Preparation of Sample (1.1) Preparation of Silicone Rubber Molded Body Two-part room temperature curable silicone rubber (trade name: KE1602, manufactured by Shin-Etsu Chemical Co., Ltd.) is added to 100 parts by weight of a curing agent (trade name: Cat.1602). , Manufactured by Shin-Etsu Chemical Co., Ltd.) was added and mixed well with a stirrer to obtain silicone rubber mixture C.
15 parts by weight of expanded Expandel 461 was added to the silicone rubber mixture C and mixed with a stirrer for 30 minutes to obtain a silicone rubber mixture D. The EXPANSEL 461 is a microballoon manufactured by Kema Nobel, whose outer shell is a copolymer of vinylidene chloride and acrylonitrile, and melts at 110 ° C. The unexpanded sphere was 10 to 16 μm. Here, the spheroid was heated at 100 ° C. for 10 minutes to form an expanded microballoon having a sphere of 40 to 60 μm.

Separately from the preparation of the silicone rubber mixtures C and D, an adhesive is applied to an aluminum core (length 370 mm, diameter 25 mm) so that the core is centered on a paper tube 15 mm thicker than the core. And a bottom lid was installed.
Thereafter, between the paper tube and the cored bar, the silicone rubber mixture C (not containing the microballoon) was poured and allowed to stand overnight at room temperature to complete the curing. Thereafter, the paper tube was removed and a solid rubber layer was formed.
Thereafter, a silicone rubber mixture D (including microballoons) is applied to the solid rubber layer to a thickness of 100 μm and left to stand for a whole day, and then the surface is polished with a polishing machine, so that about 40-60 μm microballoons are innumerable. A sponge rubber layer embedded in was formed.
By such treatment, a silicone rubber molded body (copier roll, rubber layer surface length 340 mm, see FIG. 2) having a two-layer structure in which the outer layer is sponge rubber and the inner layer is solid rubber was obtained. The hardness of this silicone rubber molding was 55 degrees with an Asuka C-type hardness meter.

(1.2) Comparative Examples 1-3
The organic solvent shown in Table 1 was put in a container, and the silicone rubber molding was immersed in the organic solvent for 30 minutes.

(1.3) Examples 1 to 14
The organic solvent of Table 1 and Table 2 is put into a container, and the silicone rubber molding is immersed in the organic solvent for 30 minutes (immersion treatment step S1), and then the organic solvent is replaced and the silicone rubber molding is immersed in the organic solvent for 30 minutes. Then, the silicone rubber molded body after immersion was placed in a constant temperature bath at 100 ° C. and dried for 1 hour (immersion treatment step S2).
In Tables 1 and 2, the organic solvent described before “/” in the column of the type of organic solvent is the organic solvent used in the previous immersion treatment step S1, and the organic solvent described after “/” It is the organic solvent used in the immersion treatment step S2.

Particularly in Examples 8 and 10 to 14, the organic solvent was heated at the temperature shown in Table 2 in both the immersion treatment steps S1 and S2.
In Examples 9 to 14, in both the immersion treatment steps S1 and S2, the organic solvent was put into a sharp ultrasonic cleaner (UT-204: 27cm × 33cm × 28cm) and covered with a silicone rubber molded body. Was immersed in an organic solvent for 30 minutes, and ultrasonic waves were oscillated for 30 minutes.
In Examples 10 to 14, in the immersion treatment step S2, the immersed silicone rubber molding is forcibly passed through a squeezing ring having an inner diameter of 40 mm, and an excess organic solvent is squeezed out from the silicone rubber molding, and then the silicone rubber molding is performed. The body was placed in a constant temperature bath at 100 ° C. and dried for 1 hour.
In Examples 11 to 14, the immersion treatment steps S1 and S2 were set as one set (set S3), and the set S3 was repeated three times.
In Examples 12 to 14, after the set S3 was repeated three times, the silicone rubber molded body was placed in a vacuum dryer (ADP-300 type manufactured by Yamato Scientific Co., Ltd.), heated at 1.33 kPa, 100 ° C. for 1 hour, and vacuumed. Dried.

(2) samples of the evaluation image forming apparatus fixing roller (Konica Minolta bizhub C754) (pressure roller) reclassified into silicone rubber moldings sample prepared above, which was placed in a stainless steel chamber of volume 1 m ³ The chamber was set to ventilate 67 L / min. After the chamber was ventilated for about 1 hour, a printing operation was performed for 10 minutes, and volatile organic compounds and ultrafine particles discharged from the apparatus during the printing operation were sampled. A toner having a volume average particle diameter of 8 μm was used.

(2.1) Volatile organic compound The Tenax tube (Tenax: registered trademark) captures air in the chamber at a suction speed of 100 mL / min, and continues for about 2 hours after the printing operation is stopped. Sampling. The volatile organic compound collected from the Tenax tube was desorbed with a heat desorption apparatus, and the amount of the volatile organic compound desorbed with a gas chromatograph mass spectrometer (GC-MS) was measured. The total amount of volatile organic compounds discharged from the apparatus (TVOC) was calculated by the calculation formula for the emission rate of Blue Angel Mark (standard of BAM (German Federal Research Institute for Materials)). The case where it is 100 mg / h or more is regarded as a practically problematic level.

(2.2) Total number of ultrafine particles Ultrafine particles G discharged into the chamber were continuously measured with a fine particle measuring instrument (model CPC3007) manufactured by TSI. The total number of ultrafine particles having a particle diameter in the range of 10 to 1000 nm observed from the start of printing to the time corresponding to 3 ventilation after the end of printing was measured. The case of 1 × 10 ⁷ pieces / mL or more is regarded as a practically problematic level.

(2.3) Number of image stains After printing 100,000 sheets, the image stains that can be observed like spots when the solid images were output on J paper (A4) were counted. A case where the image contamination per sheet is 100 or more is regarded as a practically problematic level.

(3) Summary As shown in Table 3, from the comparison between Comparative Examples 1 to 3 and Examples 1 to 14, good results were obtained in Examples 1 to 14.
From these results, it is understood that immersion treatment with two kinds of organic solvents having different solubility parameters is useful for suppressing the generation of volatile organic compounds and ultrafine particles.

In particular, from comparison between Example 1 and Examples 2 to 14, it is useful to dip the silicone rubber with an organic solvent having a solubility parameter first, and then dip treatment with an organic solvent having a different solubility parameter. I know that there is.
From a comparison between Example 2 and Examples 3 to 14, it can be seen that it is useful for the silicone rubber to have a difference in solubility parameter of the organic solvent within a certain range.
From a comparison between Example 3 and Examples 4 to 14, it can be seen that it is useful that the difference in solubility parameter between organic solvents is within a certain range.
From a comparison between Example 4 and Examples 5 to 14, it is useful that the boiling point of the organic solvent is within a certain range.
From the results of Examples 8 to 9, it can be seen that it is useful to perform a heat treatment during the immersion treatment or an ultrasonic oscillation treatment.
From the results of Example 10, it can be seen that it is useful to apply physical pressure.
From the results of Example 11, it can be seen that it is useful to repeat the dipping treatment.
From the results of Examples 12 to 14, it can be seen that it is useful to perform a vacuum heat treatment after the immersion treatment.

10 Silicone rubber molding 12 Core metal 14 Solid rubber layer 16 Sponge rubber layer 131 Pressure roller

Claims (12)

Immersing the silicone rubber molding with the first organic solvent;
Immersing the silicone rubber molded body with a second organic solvent having a solubility parameter different from that of the first organic solvent;
A method for producing a molded silicone rubber product. In the manufacturing method of the silicone rubber molding of Claim 1,
For the solubility parameter of silicone rubber,
The solubility parameter of the first organic solvent is closer to the solubility parameter of the second organic solvent;
A method for producing a silicone rubber molding, wherein the solubility parameter of the second organic solvent is separated from the solubility parameter of the first organic solvent. In the manufacturing method of the silicone rubber molding of Claim 1 or 2,
The difference in solubility parameter between the silicone rubber and the first organic solvent is from 0 to less than 2.0;
The method for producing a molded silicone rubber, wherein the difference in solubility parameter between the silicone rubber and the second organic solvent is 2.0 or more and less than 7.3. In the manufacturing method of the silicone rubber molding as described in any one of Claims 1-3,
The method for producing a molded silicone rubber product, wherein a difference in solubility parameter between the first organic solvent and the second organic solvent is 0.1 or more and 5.4 or less. In the manufacturing method of the silicone rubber molding as described in any one of Claims 1-4,
The boiling point of the first organic solvent is 35 ° C. or more and 140 ° C. or less,
A method for producing a molded silicone rubber, wherein the second organic solvent has a boiling point of 35 ° C. or higher and 80 ° C. or lower. In the manufacturing method of the silicone rubber molding as described in any one of Claims 1-5,
In at least one of the step of immersing with the first organic solvent and the step of immersing with the second organic solvent, at least one of the first organic solvent or the second organic solvent is heated. A method for producing a molded silicone rubber product. In the manufacturing method of the silicone rubber molding as described in any one of Claims 1-5,
Silicone rubber molding characterized in that ultrasonic waves are oscillated with respect to a silicone rubber molding in at least one of the step of immersing with the first organic solvent and the step of immersing with the second organic solvent. Body manufacturing method. In the manufacturing method of the silicone rubber molding as described in any one of Claims 1-5,
In at least one of the step of immersing with the first organic solvent and the step of immersing with the second organic solvent, at least one of the first organic solvent or the second organic solvent is heated. On the other hand, a method for producing a silicone rubber molding, comprising oscillating ultrasonic waves to the silicone rubber molding. In the manufacturing method of the silicone rubber molding as described in any one of Claims 1-8,
In the step of immersing with the second organic solvent, a physical pressure is applied to the silicone rubber molded body. In the manufacturing method of the silicone rubber molding as described in any one of Claims 1-9,
A method for producing a silicone rubber molded article, wherein the step of immersing with the first organic solvent and the step of immersing with the second organic solvent are alternately repeated a plurality of times. In the manufacturing method of the silicone rubber molding of Claim 10,
And a step of alternately heating the step of immersing with the first organic solvent and the step of immersing with the second organic solvent a plurality of times, and then heating and drying the silicone rubber molded body under vacuum and reduced pressure. A method for producing a molded silicone rubber product. In a manufacturing method of an image forming apparatus including a silicone rubber roller,
A step of producing the roller using a silicone rubber molded body produced by the method according to any one of claims 1 to 11,
Installing the manufactured roller at a predetermined position of the image forming apparatus;
A method for manufacturing an image forming apparatus, comprising:

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