KR20160145125A - Husking roll - Google Patents

Abstract

An object of the present invention is to provide a release roll which is excellent in durability and which is difficult to swell during use and hardly discolored at the time of storage, and the release roll of the present invention comprises a core part, a rubber layer laminated on the outer circumferential surface of the core part Wherein the rubber layer comprises a cured product of a thermosetting urethane composition containing a polyol component, an isocyanate component and a crosslinking agent, the polyol component is a polyester polyol, and the isocyanate component is TDI and / or MDI, and the crosslinking agent is 1,4-butanediol and 1,4-bis (? -Hydroxyethoxy) benzene.

Description

Removal roll {HUSKING ROLL}

The present invention relates to a release roll.

The threshing machine for agriculture is equipped with a degreasing roll. In this release roll, two release rolls are used as a pair and release rolls are arranged so as to have a predetermined interval therebetween. In the pair of release rolls arranged as described above, the rice husks are detached by putting the rice (rice with rice husk) into the clearance between the release rolls while rotating the respective release rolls at different peripheral speeds, Can be separated.

As such a roll member, a roll member composed of a cylindrical core member and a rubber layer provided around the core member is generally used (see, for example, Patent Document 1).

The rubber layer is formed using a synthetic rubber such as nitrile rubber (NBR) or styrene butadiene rubber (SBR).

Japanese Patent Application Laid-Open No. 2001-029809

Since the release roll has the above-described configuration, the rubber layer gradually wears due to the detachment of the rice hull, and when the thickness of the rubber layer is reduced due to abrasion, performance as a release roll can not be exhibited. Therefore, when the thickness of the rubber layer reaches the set value, it is necessary to replace the release roll.

Here, the conventional release roll has a problem that the durability (abrasion resistance) of the rubber layer is insufficient and the release roll must be frequently replaced.

Further, as described above, in the deaerating unit, since the pair of release rolls are rotated and used at different main speeds, the release roll (main roll) on the side where the rotation speed is higher is shifted to the side It is worn out largely as compared with the release roll (sub-roll). For this reason, it is common to use the main roll and the sub roll two times or three times until the thickness of the rubber layer reaches the set value by abrasion. In the conventional release roll as described above, there has also been a problem that frequent replacement of the main roll and the subroll is required.

Therefore, the inventors of the present invention have conducted studies to provide a release roll having excellent durability, and have found that a release roll having a rubber layer made of polyurethane has excellent durability as compared with a release roll having a rubber layer made of NBR or SBR .

However, in a release roll having a rubber layer made of polyurethane, the rubber layer expands in accordance with the temperature rise of the rubber layer in use, making it impossible to maintain the clearance between the release rolls. Eventually, the release rolls come into contact with each other, (Circumferential speed difference). Further, as the calorific value is increased, the rubber layer made of polyurethane melts to deteriorate the detaching performance, and sometimes the rubber layer is damaged. Further, the rubber layer was discolored at the time of storage, and the appearance of the rubber layer sometimes caused deterioration of the release roll.

Therefore, the present inventors have repeatedly studied to complete a release roll having a rubber layer which is excellent in durability (abrasion resistance) and hardly swells at the time of use, and is hardly discolored at the time of storage.

The release roll of the present invention is a release roll having a core portion and a rubber layer laminated on the outer circumferential surface of the core portion,

Wherein the rubber layer comprises a cured product of a thermosetting urethane composition containing a polyol component, an isocyanate component and a crosslinking agent,

The polyol component is a polyester polyol,

The isocyanate component is TDI and / or MDI,

The crosslinking agent is characterized by being 1,4-butanediol and 1,4-bis (? -Hydroxyethoxy) benzene.

In the desorption roll, the isocyanate component is preferably MDI.

In the release roll, it is preferable that the rubber layer has a JIS-A hardness (hardness) at 20 캜 of from 85 째 to less than 99 째.

In the release roll, the rubber layer preferably has a DIN abrasion loss of 60 to 100 kPa.

In the release roll of the present invention, since the rubber layer is made of the cured product of the specific thermosetting urethane composition, the durability (abrasion resistance) is remarkably excellent and can be used over a long period of time.

Further, in the above-described release roll, since thermal expansion is difficult even when the temperature of the rubber layer rises at the time of use, the clearance between the release rolls can be reliably maintained.

Further, the release rolls hardly discolor at the time of storage.

Fig. 1 (a) is a perspective view schematically showing an example of a release roll of the present invention, Fig. 1 (b) is a front view of a release roll shown in Fig. 1 .
2 is a schematic view for explaining a method of using the release roll of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The release roll of the present invention is a release roll having a core material portion and a rubber layer laminated on the outer circumferential surface of the core material portion, wherein the rubber layer is composed of a cured product of a thermosetting urethane composition containing a polyol component, an isocyanate component and a crosslinking agent. Here, the polyol component is a polyester polyol, and the isocyanate component is TDI and / or MDI, and the crosslinking agent is 1,4-butanediol and 1,4-bis (? -Hydroxyethoxy) benzene to be.

Fig. 1 (a) is a perspective view schematically showing an example of a release roll of the present invention, Fig. 1 (b) is a front view of the release roll shown in Fig. 1 (a), and Fig. 1 (c) is a sectional view taken along line A-A in Fig.

The release roll 10 shown in Figs. 1 (a) to 1 (c) comprises a core member 11 made of metal and a rubber layer 12 laminated on the outer circumferential surface of the core member 11.

The core material portion 11 is a cylindrical member provided with a mounting flange 11a for mounting the release roll 10 in the container in the decoiling.

A rubber layer 12 is formed on the entire outer peripheral surface of the core member 11 to have a uniform thickness.

The rubber layer 12 is a layer comprising a cured product of a specific thermosetting urethane composition containing a polyol component, an isocyanate component and a crosslinking agent.

Hereinafter, constituent members of the release roll of the present invention will be described.

The core part may be the same as the core part used in conventionally known release rolls. Examples of the material of the core portion include aluminum, stainless steel, iron, molybdenum, titanium, and the like.

Also, the shape and size of the core portion are not particularly limited, and may be suitably set in accordance with the specifications of the unhardening portion for mounting the release rolls and the JIS standard (JIS B 9214: rubber roll for unloading) similarly to the conventional product.

The rubber layer is composed of a cured product of a thermosetting urethane composition containing a polyol component, an isocyanate component and a crosslinking agent. The thermosetting urethane composition contains TDI and / or MDI as the isocyanate component. Therefore, the rubber layer is excellent in durability and hardly thermal expansion during use, and exhibits an excellent effect that it is hard to be discolored.

As the TDI (tolylene diisocyanate), conventionally known TDI can be used. In the TDI, the blending ratio of 2,4-TDI and 2,6-TDI (2,4-TDI / 2,6-TDI) is not particularly limited, but is preferably 65/35 to 80/20 (weight ratio). Examples of the TDI include T-80 (2,4-TDI / 2,6-TDI = 80/20), T-100 (2,4-TDI / 2,6- -65 (2,4-TDI / 2,6-TDI = 65/35).

Of course, various commercially available products may be used as the TDI.

The above-mentioned MDI (diphenylmethane diisocyanate or polymethylene polyphenylene polyisocyanate) is not particularly limited, and can be used regardless of the broadening of the molecular weight distribution. As the MDI, for example, pure MDI (4,4'-MDI), polymeric MDI and the like can be used.

Of course, various commercially available products may be used as the MDI.

The isocyanate group concentration in the thermosetting urethane composition is preferably 1.2 to 4.5% by weight.

If the isocyanate group concentration is less than 1.2% by weight, the abrasion resistance of the cured product may be deteriorated. On the other hand, when the concentration of the isocyanate group exceeds 4.5% by weight, the hardness of the cured product may become excessively high.

The isocyanate group concentration (% by weight) refers to the weight ratio of the isocyanate group contained in the total amount of the isocyanate component, the polyol component, and the crosslinking agent.

The polyol component is a polyester polyol. This is because a rubber layer having excellent abrasion resistance can be formed by a high intermolecular force expressed by a polyester polyol group having a high polarity.

Examples of the polyester polyol include those obtained by reacting a dicarboxylic acid and a glycol in accordance with a conventional method.

Examples of the dicarboxylic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and 2,6-naphthalenedicarboxylic acid, aliphatic dicarboxylic acids such as adipic acid, azelaic acid and sebacic acid, Oxycarboxylic acids such as oxybenzoic acid, and ester-forming derivatives thereof.

Of these, adipic acid is preferable, and adipic acid is particularly preferable when 1,4-butanediol is used as a glycol or a crosslinking agent. Since the C atom arrangement in adipic acid is the same quaternary arrangement as 1,4-butanediol, it is excellent in crystallization of orientation and has a crystallized structure, thereby exhibiting a strong intermolecular force. In addition, adipic acid is economical because it is inexpensive.

The dicarboxylic acid may be used alone, or two or more dicarboxylic acids may be used in combination.

Examples of the glycol include aliphatic glycols such as ethylene glycol, 1,4-butanediol, diethylene glycol, neopentyl glycol, 3-methyl-1,5-pentanediol, 1,9-nonanediol and triethylene glycol Cyclohexanedimethanol and the like, aromatic diols such as p-xylenediol, polyoxyethylene glycols such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol, and the like.

As the glycol, aliphatic glycols are preferable, and ethylene glycol and 1,4-butanediol are more preferable. It is inexpensive and suitable for forming a rubber layer having a JIS-A hardness of about 90 °.

The polyester polyol which is a reaction product of dicarboxylic acid and glycol has a linear structure, but may be a branched polyester using a tri- or higher-ester-forming component.

These glycols may be used alone or in combination of two or more.

As the polyester polyol, a polyethylene adipate-based polyester polyol, a polybutylene adipate-based polyester polyol, and a polyethylene butylene adipate-based polyester polyol are particularly preferable. It has a molecular structure suitable for forming a rubber layer having a JIS-A hardness of about 90 °, and is inexpensive.

The polyol preferably has a number average molecular weight of 1000 to 3000. If the number average molecular weight is less than 1000, the rubber layer may not exhibit satisfactory rubber elasticity and may have high rigidity. On the other hand, if the number average molecular weight exceeds 3000, a satisfactory rubber strength can not be imparted to the rubber layer, and an excessively flexible rubber layer may be obtained.

The number average molecular weight is a measured value in terms of polystyrene by GPC (gel permeation chromatography) measurement.

The crosslinking agent is 1,4-butanediol (1,4-BD), and 1,4-bis (? -Hydroxyethoxy) benzene (BHEB).

By using 1,4-BD and BHEB in combination as a crosslinking agent, the abrasion resistance of the rubber layer can be improved.

Further, when the crosslinking agent is 1,4-BD and BHEB, it is easy to develop appropriate rubber hardness and rubber stiffness in the rubber layer. Further, the thermosetting urethane composition containing 1,4-BD and BHEB as a crosslinking agent can be molded into a hand mold, because the pot life is comparatively long.

The thermosetting urethane composition preferably contains a silicone oil.

The rubber layer made of a cured product of a thermosetting urethane composition containing a silicone oil has a low coefficient of friction and a long service life. Further, when the rubber layer is provided, the sound (moving sound) at the time of detachment becomes small. When the rubber layer is provided, the surface of the release roll (the surface of the rubber layer) is surrounded by the silicone oil by the bleeding of the silicone oil, so that the water resistance (including during storage) is improved.

The silicone oil is not particularly limited and, for example, polydimethylsiloxane and its modified product can be used.

The viscosity of the silicone oil is preferably 20 to 1000 mPa · s (cps).

When the viscosity of the silicone oil is less than 20 mPa · s, the amount of the silicone oil to be bled may become excessively large. On the other hand, if it exceeds 1000 mPa · s, the dispersibility may be lowered or bleeding may not be caused.

In the thermosetting urethane composition, the content of the silicone oil is preferably 0.3 to 5% by weight, more preferably 0.5 to 3% by weight based on the total amount of the isocyanate component, the polyol component and the crosslinking agent.

When the content of the silicone oil is less than 0.3% by weight, the effect of blending the silicone oil may not be obtained sufficiently. On the other hand, if it exceeds 5% by weight, the surface of the rubber layer may become sticky, and the hardness and physical properties of the rubber layer may deteriorate.

The thermosetting urethane composition may further contain additives such as a chain extender, a reaction aid such as a crosslinking accelerator and a crosslinking retarder, a hydrolysis inhibitor, a reinforcing material such as an inorganic fiber or an inorganic filler, a colorant, a light stabilizer, a heat stabilizer, An antifungal agent, a flame retardant, a filler (extender), and the like, if necessary.

The rubber layer (cured product of the thermosetting urethane composition) preferably has a JIS-A hardness at 20 占 폚 of 85 占 or more. When the JIS-A hardness is less than 85 °, the rubber layer is excessively flexible, so that the abrasion resistance may be lowered.

The JIS-A hardness is more preferably 88 DEG or more, and more preferably 90 DEG or more.

On the other hand, the JIS-A hardness of the rubber layer at 20 캜 is preferably less than 99 °. If it exceeds 99 °, the rice may be broken at the time of detachment, and there is a fear that the occurrence rate of so-called roughness increases.

The JIS-A hardness of the rubber layer is preferably about 88 to 92 DEG when the rice to be defoliated is relatively soft japonica rice. When the rice to be unloaded is relatively hard indikami or the like, it is preferably about 92 to 96 DEG.

The JIS-A hardness can be measured in accordance with JIS K 6253 (with a measurement temperature of 20 ° C).

The "rubber layer" in the present invention corresponds to the "rubber part" in JIS B 9124.

The rubber layer (cured product of the thermosetting urethane composition) preferably has a peak temperature (Tg) of tan δ of 10 ° C or less. This is because the rubber elasticity is exhibited at a temperature of 30 to 50 ° C which is the temperature of the rubber layer at the time of use.

The rubber layer (cured product of the thermosetting urethane composition) preferably has a DIN abrasion loss of 60 to 100 kPa.

When the DIN abrasion loss is less than 60 kPa, the incidence of burning may increase at the time of detachment. On the other hand, if the weight loss of DIN exceeds 100 psi, the durability of the rubber layer becomes insufficient.

The DIN abrasion loss can be measured in accordance with the DIN abrasion test of JIS K 6264.

The thickness of the rubber layer is not particularly limited, and it may be suitably set in accordance with the specification of the unhooking period in which the release roll is mounted and the JIS standard (JIS B 9214).

The thickness of the rubber layer (indicated by T in Fig. 1 (b)) refers to a value that is one half of the difference between the outer diameter and the inner diameter of the rubber layer when it is used.

In the release roll of the present invention, in order to further improve the adhesion between the core part and the rubber layer, a primer layer and / or an adhesive layer may be formed between the core part and the rubber layer, May be carried out.

The adhesive can be formed, for example, by using a phenol-based adhesive or the like.

The primer layer can be formed using, for example, urethane, polyester, silane, polyamide, phenol primer, silane coupling agent, or the like.

As the surface treatment, for example, a roughened surface may be formed. The roughened surface may be formed by, for example, blast treatment, grinding treatment, etching treatment, plating treatment, polishing treatment, oxidation treatment or the like.

It is preferable that the relief roll has a roundness of 0.5 mm or less on the cut surface (cut surface perpendicular to the rotation axis in use). When the roundness is more than 0.5 mm, the deviation of the distance between the release rolls becomes large at the time of use, so that the removal rate may be lowered or the incidence of blistering may increase.

Next, the production method of the release roll of the present invention will be described.

The release roll can be produced, for example, by the following steps (1) and (2).

(1) First, core parts are produced. The core portion can be manufactured by a conventionally known method and can be manufactured by, for example, aluminum die casting.

Thereafter, an adhesive layer and / or a primer layer is formed on the outer circumferential surface of the core material portion, or the outer circumferential surface of the core material portion is subjected to surface treatment, if necessary.

(2) Next, a rubber layer is formed around the core portion. Here, after the core member is placed in the cylindrical mold, the above-mentioned thermosetting urethane composition is injected into the gap between the outer peripheral surface of the core member and the inner wall surface of the mold. Thereafter, the thermosetting urethane composition is cured under predetermined conditions to form a rubber layer.

The curing conditions of the thermosetting urethane composition are not particularly limited and may be suitably set according to the composition of the thermosetting urethane composition. As the curing condition, a condition of heating at 100 to 160 ° C for 30 to 90 minutes may be employed.

After the curing treatment is performed under the above conditions and the cured product is demolded from the mold, post-curing may be performed at a temperature of, for example, 100 to 160 DEG C for 3 to 48 hours.

By using such a method, a rubber layer is laminated on the outer circumferential surface of the core material portion, thereby making it possible to produce a rubber roll having a rubber layer having a uniform density throughout.

The thermosetting urethane composition used in the present invention is that the progress of curing after preparation is comparatively gentle.

In the manufacturing method of the release roll, the surface of the rubber layer may be formed by grinding if necessary. Of course, it is not necessary to perform the grinding process while demolding from the mold.

Next, a method of using the release roll of the present invention will be described.

2 is a schematic view for explaining a method of using the release roll of the present invention.

The release roll of the present invention is used as a set of two release rolls and is mounted on a conventionally known rubber roll type release unit.

That is, as shown in Fig. 2, a pair of release rolls 10A and 10B are mounted in parallel so as to have a predetermined interval L, and the release rolls 10A and 10B are rotated in opposite directions to each other, (The rotation speed Va of the release roll 10A is equal to the rotation speed Vb of the release roll 10B). Then, when the rice 1 is put between the release rolls 10A and 10B in this state, the rice chips are detached from the rice 1 by the difference in speed between the release roll 10A and the release roll 10B.

The distance L between the clearance between the release roll 10A and the release roll 10B at the time of using the release roll and the rotation speed (main speed) Va (Va) of the release roll 10A and release roll 10B , And Vb are not particularly limited and may be suitably set according to various conditions such as the specifications of the deaerating unit, the type of rice to be introduced, the drying rate, the processing speed, and the deaeration rate.

Example

Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited to the following examples.

1. Preparation of thermosetting urethane composition

(Preparation example 1)

100 parts by weight of an urethane prepolymer (SANFREN P6814, manufactured by SANYO Chemical Industry Co., Ltd.) containing MDI as an isocyanate component and polyethylene adipate ester diol (PEA) as a polyol component, 100 parts by weight of silicone oil (SH- , 0.02 parts by weight of a yellow pigment (ZA Yellow # 200, manufactured by Mikuni Kagaku Kabushiki Kaisha) and 0.02 parts by weight of a white pigment (ZA White # 2200, manufactured by Mikuni Kagaku Kogyo Co., Ltd.) Mixed with a stirrer. Next, 1.59 parts by weight of 1,4-butanediol (BASF Japan Co.) and 10.50 parts by weight of BHEB (manufactured by Mitsui Chemicals, Inc.) were further mixed to the obtained mixture to prepare a thermosetting urethane composition A.

(Preparation example 2)

(ZA Yellow # 200) and 0.02 part by weight of a white pigment (ZA White # 2200) were mixed with a stirrer. Next, 1.59 parts by weight of 1,4-butanediol (BASF Japan Co.) and 10.50 parts by weight of BHEB (manufactured by Mitsui Chemicals, Inc.) were further mixed to the obtained mixture to prepare a thermosetting urethane composition B.

(Preparation Example 3)

A thermosetting urethane composition C was prepared in the same manner as in Preparation Example 2 except that the amount of 1,4-butanediol was changed to 6.56 parts by weight and BHEB was not mixed.

(Preparation example 4)

A thermosetting urethane composition D was prepared in the same manner as in Preparation Example 2 except that 1,4-butanediol was not mixed and the mixing amount of BHEB was changed to 14.37 parts by weight.

(Preparation Example 5)

A thermosetting urethane composition E was prepared in the same manner as in Preparation Example 1 except that the mixing amount of 1,4-butanediol was changed to 6.56 parts by weight and BHEB was not mixed.

(Preparation example 6)

100 parts by weight of polyethylene adipate ester diol (PEA) (Bulkorran 2000MM, manufactured by Sumitomo Bayer Urethane Co., Ltd.), 25 parts by weight of NDI (Desmodur 15, Sumitomo Bayer Urethane Co., Ltd.) ), 0.02 part by weight of yellow pigment (ZA Yellow # 200) and 0.02 part by weight of white pigment (ZA White # 2200) were mixed with a stirrer. Next, 5.0 parts by weight of 1,4-butanediol (BASF Japan Co.) was further mixed with the obtained mixture to prepare a thermosetting urethane composition F. [

2. Preparation and Evaluation of Dispersion Roll (1)

(Example 1)

In this embodiment, a degreasing roll of the type: large 60 was produced.

First, a core portion of the shape shown in Fig. 1 was cast by aluminum die casting.

Next, in the cylindrical mold, the core portion was provided such that the distance between the outer circumferential surface of the core portion and the inner circumferential surface of the mold was substantially equally spaced over the entire circumference.

Thereafter, the thermosetting urethane composition A is injected into the gap between the outer circumferential surface of the core part and the inner circumferential surface of the mold, and is cured under the following conditions. The outer diameter and the width are adjusted by cutting, and a rubber layer is laminated on the outer circumferential surface of the core part Was prepared.

(Curing condition)

The temperature of the thermosetting urethane composition A at the time of injection was set at 105 캜 and the mold temperature was set at 130 캜 for 60 minutes.

Thereafter, the mold was demolded and subjected to post-curing at 110 DEG C for 24 hours.

(Example 2)

A release roll was produced in the same manner as in Example 1 except that the thermosetting urethane composition B was used instead of the thermosetting urethane composition A. [

(Comparative Example 1)

A release roll was produced in the same manner as in Example 1 except that the thermosetting urethane composition C was used instead of the thermosetting urethane composition A.

(Comparative Example 2)

A release roll was produced in the same manner as in Example 1 except that the thermosetting urethane composition A was used instead of the thermosetting urethane composition D.

(Comparative Example 3)

A release roll was produced in the same manner as in Example 1 except that the thermosetting urethane composition E was used instead of the thermosetting urethane composition A.

(Comparative Example 4)

Disengagement rolls were produced in the same manner as in Example 1 except that the thermosetting urethane composition F was used instead of the thermosetting urethane composition A and was cured under the following conditions.

(Curing condition)

The temperature of the thermosetting urethane composition F at the time of injection was set at 125 占 폚 and the mold temperature was set at 130 占 폚 for 60 minutes.

Thereafter, the mold was demolded and subjected to post-curing at 110 DEG C for 24 hours.

(Comparative Example 5)

The release roll (white roll, integrated type 60 type) of the product of Bando Kagakusha was used as the release roll of this comparative example. Further, the white roll is a release roll having a rubber layer containing SBR as a main component.

(Comparative Example 6)

The release roll (red roll, integrated type 60 type) of the product of Bando Kagakusha was used as the release roll of this comparative example. The red roll is a release roll having a rubber layer containing SBR as a main component.

(evaluation)

(1) Relationship between size and temperature of the release roll

The release rolls of Examples and Comparative Examples were allowed to stand for 2 hours at respective temperatures of 20 占 폚, 45 占 폚 and 70 占 폚, and then the thickness of one side of each release roll was measured.

Here, the 2-hour standing at 45 캜 and 70 캜 was carried out by keeping in an oven set at each temperature for 2 hours.

In the measurement of the thickness of one side, the dimensions from the inner surface of the core portion to the surface of the rubber layer were measured at three points using a digital nose of 20 cm, and the average value was taken as one side thickness.

In each of the release rolls, the ratio of the one side thickness measured at 20 占 폚 to the one side thickness at 45 占 폚 and 70 占 폚 relative to the one side thickness at 20 占 폚 was calculated as "100". The results are shown in Table 1.

(2) JIS-A hardness

The JIS-A hardness of the rubber layer formed on the release rolls of Examples and Comparative Examples was measured according to JIS K 6253. However, the measurement temperature was 20 占 폚, and the measurement part was set at three places. The results are shown in Table 1.

(3) DIN abrasion loss

The DIN abrasion loss of the rubber layer formed on the release rolls of Examples and Comparative Examples was evaluated.

The evaluation of the DIN abrasion loss was made by separately preparing a test piece (16 mm in diameter × 6 mm in thickness) having the same composition as that of the rubber layer and using the test piece in accordance with JIS K 6264, A method) and an addition force of a test piece: 10 N. The results are shown in Table 1.

(4) Peak temperature (Tg) of tan?

The peak temperatures (Tg) of the tan delta of the rubber layers formed in the release rolls of Examples 1 and 2 and Comparative Examples 4 to 6 were evaluated.

The evaluation of the peak temperature of tan delta was made by separately preparing a test piece (3 mm wide x 40 mm long x 1 mm thick) having the same composition as that of the rubber layer and using a Leopectol-DVE-V4 (manufactured by Rheology) And the 10 Hz sine wave tensile excitation was measured at a temperature range of 60 to 100 ° C. The temperature at which the loss coefficient tan? Represents the maximum value is defined as the peak temperature of tan?.

(5) Change in color tone (presence or absence of discoloration)

The change in color tone of the rubber layer formed on the release rolls of Examples and Comparative Examples was evaluated.

A test piece (size: 200 mm in length x 70 mm in width x 2 mm in thickness) having the same composition as that of the rubber layer was separately prepared and evaluated by using a Sunshine Weather Meter (Sunshine Weather Meter S80 manufactured by Suga Shikeki Co., Ltd.) ), The test piece was exposed for 120 hours under the conditions specified in the accelerated weathering resistance test of JIS K 6732, and then the change in color tone was observed. The results are shown in Table 1.

As shown in Table 1, the release roll of the present invention having a rubber layer composed of a cured product of a specific thermosetting urethane composition is hardly swollen at the time of use and has dimensional stability equivalent to that of a commercially available product that has already been established in the market have.

It has also become clear that the abrasion resistance of the rubber layer is improved by using 1,4-BD and BHEB in combination as a crosslinking agent.

It has also become clear that the release roll of the present invention does not discolor during storage.

3. Fabrication and evaluation of strip roll (2)

(Example 3)

In the present embodiment, a deburring roll of the type: large 100 was produced.

Herein, except that the shape and dimensions were changed, a release roll was produced using the same method as in Example 1. [

(Example 4)

A release roll was produced in the same manner as in Example 3 except that the thermosetting urethane composition B was used instead of the thermosetting urethane composition A.

(Comparative Example 7)

A release roll was produced in the same manner as in Example 3 except that the thermosetting urethane composition C was used instead of the thermosetting urethane composition A.

(Comparative Example 8)

A release roll (white roll, integrated type 100 type) of a product of Bando Kagakusha was used as a release roll of this comparative example.

(evaluation)

(6) Performance evaluation of degreasing roll

In the following three facilities, the relationship between the amount of debris and the amount of wear of the rubber layer was evaluated.

In Toyooka Country Elevator, we conducted a listening survey on the past performance regarding the service life of the commercial release roll.

(6-1) Evaluation of release rolls prepared in Examples 3 and 4

Tajima Agricultural Cooperative Association, and Toyooka Country Elevator.

The shaving machine was a product of Satake Sha, type: HA10NC (introduced in 2004).

Rice, item: rice, moisture (based on brown rice) 14.3 ~ 14.8%, the temperature of the rice was 5 ~ 15 ℃.

The processing speed was about 4.6 tons / hour.

The removal rate in the case of using the release roll of Example 3 was 78%, and the removal rate in the case of using the release roll of Example 4 was 79%.

In this evaluation, about 300 tons of rice were treated, and the abrasion amount of the rubber layer of the release roll at that time was measured. At this time, the amount of abrasion was calculated by taking the thickness of the rubber layer remaining on the end face of each of the pair of release rolls (main roll and boule roll) so as to be a difference from the thickness of the initial rubber layer (25 mm). The results are shown in Table 2.

In Table 2, the abrasion amount in front of and in front of the main roll refers to the amount of abrasion measured on the cross section positioned in front when the release roll was mounted on the ungroove, Refers to the amount of wear measured on the cross section located on the inner side when mounted.

On the basis of the measurement result of the abrasion amount, the anticipated limit abrasion amount (the expected value of the weight of the detachable rice) when the abrasion roll was used up to the service life (until the thickness of the rubber layer became 5 mm) was calculated . The results are shown in Table 2.

The predicted limit depletion amount was calculated by calculating the average value (average wear amount) of the four wafers measured by the above-described method, and calculating the average wear amount (A) and the actual treated rice weight (B) (1).

Estimated limit depletion = weight of rice (B) ÷ [average wear (A) / 20] (1)

In addition, as a result of the listening inspection in the Toyoka country elevator, it has become clear that the lifetime (marginal dehydration amount) of the release roll (white roll, integrated type 100 type) of the product of Bando Kagakusha is roughly 300 to 400 tons.

(6-2) Evaluation of release roll prepared in Comparative Example 7

Tajima agricultural cooperative, Izu-shi Country elevator evaluated.

The degaussing machine was manufactured by Satsuke Kabushiki Kaisha, type: HPS100HEA (introduced in 1999). In addition, rice was at 14.5 ~ 16.3% moisture content (based on brown rice) and at a temperature of 15 ~ 28 ℃ for rice hinoki.

The processing speed was about 2.5 tons / hour.

The removal rate in Comparative Example 7 was 79%.

In this evaluation, about 220 tons of rice was treated, and the wear amount of the rubber layer of the release roll at that time was measured. The results are shown in Table 2.

Based on the measurement result of the abrasion amount, the anticipated limit removal amount was calculated. The calculation results are shown in Table 2.

The method of measuring the amount of wear and the method of calculating the expected limit depletion amount are the same as those in the above (6-1).

(6-3) Evaluation of release roll prepared in Comparative Example 8

Hyogo Minami Agricultural Cooperative, Inami Country Elevator.

The degaussing machine was a product of Satake Sha, type: HPS100HEA (introduced in 1999).

Rice, Item: Hinohikari and Kinuhikari, water content (based on brown rice): 14.3% (Hinohikari), 14.1% (Kinuhikari).

The processing speed was set at about 2.0 tons / hour.

The removal rate in the case of using the release roll of Comparative Example 8 was about the same as that in the case of using the conventional release roll.

In this evaluation, about 350 tons of rice was treated, and the abrasion amount of the rubber layer of the release roll at that time was measured. The results are shown in Table 2.

Based on the measurement result of the abrasion amount, the anticipated limit removal amount was calculated. The calculation results are shown in Table 2.

The method of measuring the amount of wear and the method of calculating the expected limit depletion amount are the same as those in the above (6-1). In Comparative Example 8, however, the amount of wear was measured only in front of the main roll and in the front of the roll.

As shown in Table 2, the release roll of the present invention having a rubber layer made of a cured product of a specific thermosetting urethane composition can be used over a long period of time because of its excellent durability, and the replacement frequency of the release roll can be reduced.

It has also become clear that when the thermosetting urethane composition contains silicone oil, durability is improved.

10, 10A, 10B:
11:
11a: Mounting flange
12: Rubber layer

Claims (4)

A release roll comprising a core part and a rubber layer laminated on the outer circumferential surface of the core part,
Wherein the rubber layer comprises a cured product of a thermosetting urethane composition containing a polyol component, an isocyanate component and a crosslinking agent,
Wherein the polyol component is a polyester polyol,
The isocyanate component is TDI and / or MDI,
Wherein the cross-linking agent is 1,4-butanediol and 1,4-bis (? -Hydroxyethoxy) benzene. The method according to claim 1,
Wherein the isocyanate component is MDI. 3. The method according to claim 1 or 2,
Wherein the rubber layer has a JIS-A hardness (hardness) of at least 85 ° and less than 99 ° at 20 ° C. 4. The method according to any one of claims 1 to 3,
Wherein the rubber layer has a DIN abrasion loss of 60 to 100 kPa.

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