JP6289203B2 - Mold release recovery resin composition and mold release recovery method using the same - Google Patents

Description

  The present invention relates to a mold release recovery resin composition and a mold release recovery method using the same.

  Conventionally, when molding a sealing molded product such as an integrated circuit using a thermosetting resin such as an epoxy resin, a silicone resin, a phenol resin, and a polyimide resin, if the molding is continued, a stain is generated on the inner surface of the mold. Even if the molding is continued as it is, there are many cases where the surface of the sealed molded product becomes dirty or the sealed molded product adheres to the mold surface and the molding work of the sealed molded product cannot be continued. It was. Therefore, it is necessary to periodically clean the mold surface, and the mold surface is cleaned by molding several mold cleaning compositions every time several hundred shots of the molded molded product are shot. .

Furthermore, in the molding of the sealed molded product, immediately after cleaning using the mold cleaning composition, the surface of the mold is clean, and therefore the sealed molded product tends to stick to the inner surface of the mold. In order to prevent the appearance of the sealed molded product from being deteriorated due to sticking of the molded product, the mold release recovery resin composition is molded on the mold inner surface after cleaning the mold. A method of imparting sex has been proposed. The sealed molded product that is molded after imparting releasability to the inner surface of the mold has a good appearance because the sealed molded product does not stick to the inner surface of the mold.
Usually, the molding conditions such as the mold temperature and the mold pressure in the molding of the mold release recovery resin composition are the same as the molding conditions using the mold cleaning composition performed before the mold release recovery operation. It is the same as the molding conditions using the sealed molded product performed after the mold release recovery operation.

  Such a mold release recovery resin composition is obtained by adding at least one of synthetic rubber and synthetic resin, a release agent and a vulcanizing agent, as described in Patent Document 1 and Patent Document 2. It has been known.

JP 2010-149358 A JP 2007-238731 A

However, the conventional mold release recovery resin composition has a problem that it is difficult to uniformly give the entire mold inner surface.
For example, the mold release recovery resin composition described in Patent Document 1 contains ethylene-propylene-terpolymer rubber and polyethylene wax or amide wax as a release agent. This composition lacks the hardness and strength of the composition itself, the composition flows excessively during the mold release recovery operation, the resin composition cannot be sufficiently filled in the mold, and even if the mold is pressed Since no pressure is uniformly applied to the composition, it is difficult to uniformly impart releasability to the entire inner surface of the mold.
Moreover, the mold release recovery resin composition described in Patent Document 2 includes an epoxy resin and carnauba wax as a release agent. This composition has poor compatibility between the epoxy resin and the carnauba wax, and the release agent is not sufficiently dispersed in the composition. When the mold release recovery operation is performed, the mold release is performed on the entire inner surface of the mold. It is difficult to impart the properties uniformly. Further, since the composition contains an epoxy resin, the composition itself has poor storage stability. For example, in a mold release recovery operation using a resin composition after 6 months have passed since manufacture, the inner surface of the mold There is a problem in that the performance of imparting releasability to the entire surface is reduced.

In general, the mold release recovery resin composition contains more mold release agent than the mold cleaning composition used before the mold release recovery operation.
By adding a large amount of a release agent to the conventional mold release recovery resin composition, it is possible to improve the release property imparted to the inner surface of the mold. However, the mold release recovery resin composition containing a large amount of such a mold release agent has a resin composition that is remarkably insufficient in strength and becomes brittle. When removing the composition, there is a problem that the resin composition breaks or the resin composition sticks to the inner surface of the mold, and the workability of taking out the resin composition is remarkably inferior, so it is not suitable for practical use.
The present inventor uses a synthetic rubber containing acrylonitrile having both excellent hardness and elasticity as the synthetic rubber included in the mold release recovery resin composition. It was thought that by allowing the fluid to flow without deficiency and uniformly pressurizing the entire surface of the inner surface of the mold, it was possible to uniformly impart releasability to the entire inner surface of the mold.
However, since the synthetic rubber containing acrylonitrile has a high polarity, there is a problem that the compatibility with a release agent such as a polyethylene wax having a low polarity, which has been conventionally used in a mold release recovery resin composition, is poor. . For this reason, the synthetic rubber containing acrylonitrile and the release agent cannot be uniformly dispersed in the resin composition, and in the mold release recovery work using this resin composition, the entire inner surface of the mold has a release property. It was difficult to apply uniformly.

  The present invention has been made in view of the above problems, and a mold release recovery resin composition capable of uniformly imparting release properties to the entire inner surface of the mold and a mold release recovery method using the same. The purpose is to provide.

Specific means for achieving the above object are as follows.
(1) A mold release recovery resin composition comprising a synthetic rubber containing acrylonitrile, a vulcanizing agent, and an unsaturated fatty acid amide.

(2) The mold release recovery resin composition according to (1), wherein the content of acrylonitrile in the synthetic rubber is 1% by mass or more and 50% by mass or less.

(3) The mold release recovery resin composition according to (1) or (2), wherein the unsaturated fatty acid amide is at least one selected from the group consisting of erucic acid amide, oleic acid amide, and nervonic acid amide. It is a thing.

(4) The mold separation according to any one of (1) to (3), wherein the content of the unsaturated fatty acid amide is from 1 part by weight to 50 parts by weight with respect to 100 parts by weight of the synthetic rubber. It is a resin composition for mold recovery.

(5) A mold release recovery method using the mold release recovery resin composition according to any one of (1) to (4).

  ADVANTAGE OF THE INVENTION According to this invention, the mold release recovery resin composition which can provide mold release property uniformly to the whole mold inner surface, and the mold release recovery method using the same can be provided.

  Hereinafter, specific embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and may be appropriately modified within the scope of the object of the present invention. Can do.

In this specification, the mold release recovery resin composition may be simply referred to as a resin composition.
In addition, the “entire surface of the inner surface of the mold” means the entire area in contact with an object to be molded such as a sealed molded object molded by the molding die.
Moreover, in this specification, the mold release recovery method using the mold release recovery resin composition may be referred to as mold release recovery work.
Furthermore, the numerical range indicated using “to” in this specification indicates a range including the numerical values described before and after “to” as the minimum value and the maximum value, respectively. Unless otherwise specified, the amount of each component in the composition is represented by the total amount of a plurality of types of substances when each component includes a plurality of types of substances.

  The mold release recovery resin composition of the present invention has removed dirt on the mold surface generated in the molding process of a sealing molded product selected from the group consisting of epoxy resin, silicone resin, phenol resin and polyimide resin. By forming later, mold release property can be uniformly imparted to the entire inner surface of the mold. Therefore, the sealed molded product molded after the resin composition of the present invention is molded does not stick to the mold, and the appearance is good.

(Resin composition for mold release recovery)
The mold release recovery resin composition of the present invention contains a synthetic rubber containing acrylonitrile, a vulcanizing agent, and an unsaturated fatty acid amide.
The reason why the resin composition of the present invention has the effect of imparting releasability uniformly to the entire inner surface of the mold is as follows.

When using a mold release recovery resin composition that has both low strength and elasticity of the resin composition itself, the resin composition will flow excessively during the mold release recovery operation, so the resin composition is sufficient for the mold. It is difficult to uniformly apply pressure to the resin composition even if the mold is pressurized. For this reason, it is difficult for a resin composition having both low strength and elasticity of the resin composition itself to uniformly impart releasability to the entire inner surface of the mold.
On the other hand, when the resin composition for mold release recovery, which has high strength and elasticity of the resin composition itself, is used, the resin composition is difficult to flow during the mold release recovery operation. It is difficult to uniformly provide mold releasability to the entire inner surface of the mold.
That is, in the mold release recovery operation, it is necessary to use a mold release recovery resin composition whose strength and elasticity are both in an appropriate range.
Further, when a mold release recovery resin composition in which the synthetic rubber and the release agent are not sufficiently compatible, the release agent is sufficiently dispersed in the mold release recovery resin composition. Therefore, the mold release is not uniformly applied to the inner surface of the mold during the mold release recovery operation.
The resin composition of the present invention includes a synthetic rubber containing acrylonitrile and a specific release agent, so that the strength and elasticity of the resin composition are both appropriate and the fluidity of the resin composition during mold release recovery work. Since the release agent is sufficiently dispersed in the mold release recovery resin composition because the synthetic rubber and the release agent contained in the resin composition are sufficiently compatible with each other, The mold releasability can be uniformly imparted to the entire inner surface of the mold.

(Synthetic rubber)
The synthetic rubber containing acrylonitrile that can be used in the resin composition of the present invention is a synthetic rubber containing acrylonitrile as a constituent unit. Examples of such a synthetic rubber include a copolymer of acrylonitrile and another monomer. Examples of such a copolymer include a copolymer of acrylonitrile and 1,3-butadiene.
In the present specification, a synthetic rubber containing acrylonitrile may be referred to as a nitrile rubber.
In general, nitrile rubber has a characteristic of high elasticity. Since the resin composition of the present invention contains nitrile rubber, it has sufficient elasticity, and the resin composition does not flow excessively during the mold release recovery operation, and can fill up the details inside the mold. The mold releasability can be uniformly imparted to the entire inner surface of the mold.
In general, nitrile rubber is characterized by high strength. Since the resin composition of the present invention contains nitrile rubber, the resin composition has sufficient strength, and has good characteristics in that workability when removing the resin composition from the mold during mold release recovery work is good.
In general, a mold release recovery resin composition containing a large amount of a release agent has a reduced strength.
If the mold release recovery resin composition has insufficient strength, the resin composition becomes brittle during the mold release recovery operation, causing cracks or the like, and the resin composition sticking to the inner surface of the mold Happens.
Since the resin composition of the present invention contains nitrile rubber, the resin composition itself has sufficient strength and elasticity even if it contains a large amount of unsaturated fatty acid amide as a release agent. Therefore, since the resin composition does not flow excessively during the mold release recovery operation and can be uniformly filled to the details inside the mold, the resin composition of the present invention has a release property on the entire surface of the mold inside. Can be applied uniformly.

The synthetic rubber containing acrylonitrile that can be used in the present invention may include synthetic rubbers other than nitrile rubber. By including a synthetic rubber other than nitrile rubber, the resin composition of the present invention makes it easy to adjust the strength and elasticity of the resin composition itself, and the mold release is achieved by the appropriate fluidity of the resin composition. The resin composition can be filled up to the details inside the mold during the recovery operation, and the mold releasability can be more uniformly imparted to the entire inner surface of the mold.
Synthetic rubbers other than nitrile rubber that can be used in the resin composition of the present invention include ethylene-propylene rubber, ethylene-propylene-diene rubber, butadiene rubber, natural rubber, silicone rubber, acrylic rubber, styrene rubber, isoprene rubber, and epichlorohydrin rubber. And hydrogenated nitrile rubber. In particular, butadiene rubber and styrene rubber can be preferably used because they have high compatibility with nitrile rubber and can maintain the strength of the resin composition.

The content of acrylonitrile in the synthetic rubber that can be used in the resin composition of the present invention is preferably 1% by mass to 50% by mass, more preferably 3% by mass to 48% by mass, and more preferably 5% by mass to 45% by mass. The following is more preferable.
In this specification, the content of acrylonitrile in the synthetic rubber means the content of components derived from acrylonitrile with respect to the total amount of the synthetic rubber included in the resin composition. For example, when the resin composition contains 5 parts by mass of a nitrile rubber whose component derived from acrylonitrile is 20% by mass and 95 parts by mass of butadiene rubber, the content of acrylonitrile is 1% by mass.
When the content of acrylonitrile in the synthetic rubber is 1% by mass or more, the strength of the resin composition of the present invention is sufficiently high, and the resin composition does not flow excessively during the mold release recovery operation, and the inside of the mold It is preferable that the pressure is uniformly applied to the entire surface, so that the resin composition can be filled up to the details inside the molding die, and the mold releasability can be more uniformly imparted to the entire surface inside the die. Furthermore, the synthetic rubber contained in the resin composition and the mold release agent are compatible with each other, so that the mold release agent is sufficiently dispersed in the mold release recovery resin composition, and the entire surface of the mold inside is released. Can be imparted more uniformly. Moreover, if it is 50 mass% or less, the elasticity of the resin composition is appropriate, the resin composition flows sufficiently during the mold release recovery operation, the resin composition fills the details inside the molding die, This is preferable because the mold releasability can be more uniformly imparted to the entire inner surface of the mold.

  The content of acrylonitrile in the synthetic rubber can be determined by measuring according to JIS K6384.

The nitrile rubber that can be particularly preferably used in the resin composition of the present invention is a copolymer of acrylonitrile and butadiene. Such a copolymer is a low nitrile type having an acrylonitrile content of less than 25% by mass, a medium nitrile type of 25% by mass to 30% by mass, a medium / high nitrile type of 30% by mass to 35% by mass, and 35% by mass to Examples include a high nitrile type of 42% by mass and an extremely high nitrile type exceeding 42% by mass.
Since the kneadability at the time of preparation of the resin composition is excellent, a medium-high nitrile type nitrile rubber can be particularly suitably used for the resin composition of the present invention.

  The nitrile rubber that can be used for the resin composition of the present invention is a low nitrile type copolymer, product name N250SL manufactured by JSR; Product name N239SV, JSR product name NN220S, which is a high nitrile type, and JSR product name 215SL, which is an extremely high nitrile type.

(Vulcanizing agent)
The vulcanizing agent that can be used in the resin composition of the present invention is not particularly limited as long as it can crosslink synthetic rubber, and may not contain sulfur.
In this specification, vulcanization is a concept including both cross-linking of synthetic rubber using sulfur and cross-linking of synthetic rubber using peroxide.

The vulcanizing agent that can be suitably used for the resin composition of the present invention is an organic peroxide. When the resin composition of the present invention contains an organic peroxide, the inner surface of the mold does not corrode, and the synthetic rubber necessary for mold release is sufficiently advanced in a short time during the mold release recovery operation. The resin composition is preferable because it can be easily removed from the mold.
Organic peroxides that can be suitably used in the resin composition of the present invention include di-t-butyl peroxide, di-t-amyl peroxide, dicumyl peroxide, and 2,5-dimethyl-2,5- Dialkyl peroxides such as di- (t-butylperoxy) hexane, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) ) Perfluorocarbon, 2,2-bis (t-butylperoxy) octane, n-butyl 4,4-bis (t-butylperoxy) valerate and 2,2-bis (t-butylperoxy) butane Examples include oxyketals.
The vulcanizing agent that can be used in the resin composition of the present invention may be used alone or in combination of two or more according to the design of the resin composition.

  Examples of the vulcanizing agent that can be suitably used in the present invention include Park Mill D-40 manufactured by NOF Corporation, Perhexa 25B-40 manufactured by NOF Corporation, and the like.

  The content of the vulcanizing agent in the resin composition of the present invention is preferably 0.1 parts by mass or more and 6 parts by mass or less with respect to 100 parts by mass of the synthetic rubber included in the resin composition. More preferably, it is 2 parts by mass or more and 4 parts by mass or less. When the content of the vulcanizing agent is 0.1 parts by mass or more with respect to 100 parts by mass of the synthetic rubber, the vulcanization sufficiently proceeds during the mold release recovery operation using the resin composition, and the resin composition This is preferable because the material does not become brittle and the workability is good. Moreover, if content of a vulcanizing agent is 6 mass parts or less, since generation | occurrence | production of an odor can be suppressed at the time of mold release recovery work, it is preferable.

(Unsaturated fatty acid amide)
The unsaturated fatty acid amide that can be used in the resin composition of the present invention acts as a so-called mold release agent that imparts releasability to the inner surface of the mold.
An unsaturated fatty acid amide is an amide compound having a double bond or a triple bond in its molecular structure. Unsaturated fatty acid amides are generally characterized by a lower melting point than saturated fatty acid amides. Usually, the surface temperature of the mold during the mold release recovery operation is 90 ° C to 200 ° C. Therefore, in a mold release recovery operation using a resin composition containing an unsaturated fatty acid amide, the unsaturated fatty acid amide can be sufficiently melted in the resin composition. A resin composition containing an unsaturated fatty acid amide having a low melting point can provide a more uniform release property to the entire inner surface of the mold because the unsaturated fatty acid amide sufficiently melts during the mold release recovery operation. it can.

The unsaturated fatty acid amide that can be used in the resin composition of the present invention is preferably at least one selected from the group consisting of ω-9 unsaturated fatty acid amides such as erucic acid amide, oleic acid amide, and nervonic acid amide. .
The melting point of these unsaturated fatty acid amides is characterized by being lower than the melting point of saturated fatty acid amides having the same carbon number in the molecular structure. For example, the melting point of erucic acid amide, which is an unsaturated fatty acid amide having 22 carbon atoms, is 79 to 81 ° C., whereas the melting point of behenic acid amide, which is a saturated fatty acid amide having 22 carbon atoms, is 110 to 113 ° C. .

  Examples of the unsaturated fatty acid amide that can be suitably used in the resin composition of the present invention include Alfro P10 manufactured by NOF Corporation and Alfro E10 manufactured by NOF Corporation.

  The content of the unsaturated fatty acid amide that can be used in the resin composition of the present invention is preferably 1 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the synthetic rubber included in the resin composition. More preferably, it is 40 parts by mass or less. If the content of the unsaturated fatty acid amide is 1 part by mass or more, the amount of the release agent is sufficient, so that the release property to the entire inner surface of the mold can be sufficiently imparted. Further, if it is 50 parts by mass or less, the resin composition does not have sufficient strength and elasticity, the resin composition does not flow excessively during the mold release recovery operation, and is uniform in the resin composition when the mold is pressed. Since the pressure is applied to the resin composition and the resin composition fills the details inside the mold, it is preferable because the mold releasability can be more uniformly imparted to the entire surface of the mold.

In the synthetic rubber and unsaturated fatty acid amide that can be contained in the resin composition, when the difference in these solubility parameters is small, the compatibility between the synthetic rubber and the release agent is good.
A preferable range of the solubility parameter of the nitrile rubber that can be used in the resin composition of the present invention is 8.7 to 10.8. Moreover, the preferable range of the solubility parameter of the unsaturated fatty acid amide which the resin composition of this invention can contain is 9.5-10.
The resin composition of the present invention has a small difference in solubility parameter between the nitrile rubber and the release agent contained in the resin composition, and the nitrile rubber and the release agent are sufficiently compatible with each other. Is sufficiently dispersed, and the mold releasability can be uniformly imparted to the entire inner surface of the mold.
The synthetic rubber used in the conventional mold release recovery resin composition has a solubility parameter of about 7.9 for ethylene-propylene rubber and about 8.4 for butadiene rubber. In addition, the solubility parameter of polyethylene wax, which is a mold release agent used in a conventional mold release recovery resin composition, is about 8.0. When a mold release recovery resin composition containing nitrile rubber and polyethylene wax is prepared, the difference in solubility parameter is large, so these cannot be sufficiently compatible with each other. Dispersion becomes insufficient, and it is difficult to impart release properties uniformly to the entire inner surface of the mold during the mold release recovery operation.

  The resin composition of this invention can use together mold release agents other than the said unsaturated fatty acid amide as needed. Examples of the release agent other than the unsaturated fatty acid amide that can be used in the present invention include LICOWAX PED521, which is a polyolefin type release agent.

(Other ingredients)
The resin composition of the present invention preferably contains an inorganic filler in order to obtain the strength of the resin composition. The inorganic filler is not particularly limited, and can be appropriately selected from inorganic fillers suitably used for ordinary mold release recovery resin compositions.
Examples of the inorganic filler that can be used in the present invention include silica, alumina, calcium carbonate, aluminum hydroxide, and titanium oxide. In particular, it is preferable to use silica and titanium oxide for the resin composition because the resin composition does not damage the mold surface during the mold release recovery operation.

The particle size of the inorganic filler that can be used in the present invention is not particularly limited, but the mold release property can be uniformly distributed over the entire inner surface of the mold by sufficiently flowing the resin composition during the mold release recovery operation. Since it can provide, it is preferable that it is the range of 0.1 micrometer-20 micrometers, and it is more preferable that it is the range of 5 micrometers-18 micrometers.
The particle diameter is a volume average particle diameter measured with a Coulter counter (manufactured by Beckman Coulter) using an aperture diameter of 70 μm.

  The resin composition of the present invention preferably contains the inorganic filler in a range of 10 parts by mass to 100 parts by mass with respect to 100 parts by mass of the synthetic rubber included in the resin composition, and is 30 parts by mass to 60 parts by mass. It is more preferable to include within a range. If it is 10 parts by mass or more, the strength of the resin composition becomes appropriate, the resin composition does not flow excessively during the mold release recovery work, and the interior of the mold is sufficiently filled up to the details inside the mold. It is preferable because release properties can be more uniformly imparted to the entire surface. Further, if it is 100 parts by mass or less, the elasticity of the resin composition becomes appropriate, the resin composition flows sufficiently during the mold release recovery work, and the resin composition fills the details inside the mold. It is preferable because release properties can be more uniformly imparted to the entire inner surface.

The resin composition of the present invention can further contain additives such as a vulcanization aid, a vulcanization accelerator, and a vulcanization acceleration aid as necessary.
A vulcanization aid is an additive used in combination with a vulcanizing agent to improve the reaction rate of the vulcanization reaction.
A vulcanization accelerator is an additive that is used in combination with a vulcanizing agent to significantly accelerate the vulcanization reaction rate, shorten the vulcanization time, lower the vulcanization temperature, and further reduce the amount of vulcanizing agent added. is there.
A vulcanization acceleration aid is an additive that improves the vulcanization acceleration effect by its chemical action when used in combination with a vulcanization accelerator.
Examples of the vulcanization aid that can be suitably used in the resin composition of the present invention include acrylic acid monomers and sulfur.
Further, vulcanization accelerators include guanidines such as diphenylguanidine and triphenylguanidine, aldehyde-amines such as formaldehyde-paratoluidine condensate, acetaldehyde-aniline reactants, and aldehyde-ammonia, 2-mercaptobenzothiazole, dibenzo. Examples include thiazoles such as thiazyl disulfide.
Furthermore, examples of the vulcanization acceleration aid include magnesia, resurge, lime and the like.

  The resin composition of the present invention contains inorganic or organic pigments such as petals, bitumen, iron black, ultramarine, carbon black, lithopone, titanium yellow, cobalt blue, Hansa yellow, quinacridone red, as necessary. Can do.

  The resin composition of the present invention can further contain a solvent such as a lubricant, a plasticizer, a tackifier, a foaming agent, a scorch inhibitor, water and various organic solvents, if necessary. These are appropriately selected according to the shape of the mold and the physical properties of the sealed molded product.

The preparation method of the resin composition of this invention is not specifically limited, A well-known method is employable.
The resin composition of the present invention can be prepared, for example, by the following method.
A synthetic rubber containing acrylonitrile, a vulcanizing agent, an unsaturated fatty acid amide, and various additives are placed in a pressure type kneader with a jacket and kneaded to obtain a kneaded product. Subsequently, the obtained kneaded material is prepared into a sheet by passing it through a pressure roll.
In addition, it can replace with the said pressure type kneader and a Banbury mixer, a roll mixer, etc. can be used.
Moreover, the shape of the resin composition of this invention can be suitably selected according to the metal mold | die to be used other than a sheet form.
Furthermore, when preparing the resin composition of this invention in a sheet form, this thickness is although it does not specifically limit, The range of 3 mm-10 mm can be illustrated.

(Use)
The resin composition of the present invention can impart releasability to the inner surface of the mold after removing the dirt on the inner surface of the mold with the mold cleaning composition. The encapsulated molded product molded after the mold release recovery operation using the resin composition of the present invention does not stick to the inner surface of the mold, and there is no molding defect, poor appearance, or the like.
Examples of the molding die in the present invention include an optical member sealing die, a semiconductor material sealing die, and a rubber molding die. Specifically, a sealing mold for a light emitting diode (LED), a sealing mold for a semiconductor package, a rubber packing molding mold, a thermosetting resin component molding mold, and the like can be given. Molding molds suitable for mold release recovery work using the resin composition of the present invention are LED sealing molds, semiconductor package sealing molds, and the like.

  The kind of resin used for the sealing molded product is not particularly limited, and examples thereof include epoxy resin, melamine resin, urea resin, silicone resin, phenol resin, and polyimide.

  The resin composition of the present invention can be applied to any mold release recovery method of transfer type and compression type. Since the workability can be improved and the mold release recovery work time can be shortened, the resin composition of the present invention is preferably applied to a compression type.

  The mold temperature at the time of mold release recovery work using the resin composition of the present invention is each of the molded moldings molded at the time of mold cleaning before the mold release recovery work and after the mold release recovery work. It is appropriately selected according to the physical properties. In the sealed molded product, when the resin to be molded is an epoxy resin, an example of the mold temperature is about 170 ° C.

(Release method of mold release)
The mold release recovery method of the present invention includes a step of placing the mold release recovery resin composition of the present invention on the inner surface of a molding die (hereinafter also referred to as “placement step”), And a step of heating the mold provided with the mold release recovery resin composition (hereinafter also referred to as “heating step”). The mold release recovery method may have other steps as necessary.

(Placement process)
The placing process is a process of placing the mold release recovery resin composition of the present invention on the inner surface of the mold. The method for placing the resin composition of the present invention on the inner surface of the molding die is not particularly limited, and a known method can be employed. Specifically, it can be performed by a known method such as a compression molding method or a transfer molding method.
When placing the resin composition of the present invention on the inner surface of the mold, even if it is placed so as to cover a part of the surface of the mold cavity portion, it is placed so as to cover the entire surface. However, it is more preferable to place the composition so as to cover the entire surface because the mold releasability can be more uniformly imparted to the entire inner surface of the mold.

(Heating process)
The heating step is a step of heating the mold release recovery resin composition of the present invention placed on the inner surface of the mold. In the heating step, the resin composition of the present invention is pressurized by applying pressure to the molding die with heating, and fills the details inside the molding die.
The heating method and heating conditions (temperature, time, number of times, pressure, etc.) are not particularly limited. For example, the mold cleaning composition used before the placing step and the sealing molded product molded after the heating step are used. Known methods and conditions can be appropriately selected according to the type of resin and the type of the resin composition for mold release recovery of the present invention.

In the heating process, for example, from the viewpoint of simplicity, it is preferable to perform the mold release recovery operation under the same conditions as the molding conditions performed before and after the placing process.
The temperature of the mold in the heating step is preferably 90 ° C to 200 ° C, more preferably 160 ° C to 190 ° C, and further preferably 170 ° C to 180 ° C.

  The heating time is not particularly limited as long as the mold release recovery resin composition is sufficiently vulcanized and evenly spread over the entire inner surface of the mold, but it is 150 seconds to 500 seconds. It is preferable that it is 180 seconds to 360 seconds. If the heating time is 150 seconds or longer, the vulcanization of the resin composition proceeds sufficiently, and the resin composition can be prevented from sticking to the inner mold surface during the mold release recovery operation. Moreover, if it is 500 seconds or less, workability | operativity of a mold release recovery operation | work will become favorable.

  The placing process and the heating process may be repeated a plurality of times. The number of repetitions of the placing step and the heating step (hereinafter also referred to as “the number of shots”) is preferably 1 to 5 times, and more preferably 1 to 2 times.

(Other processes)
The mold release recovery method of the present invention may be provided with other steps as necessary. Examples of other processes include a preheating process and a pre-pressurizing process.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples as long as the gist thereof is not exceeded. Unless otherwise specified, “part” and “%” are based on mass.

(Resin composition for mold release recovery)
[Example 1]
In a 3000 ml jacketed pressure kneader, 254 g of nitrile rubber (N239SV, manufactured by JSR Corporation, acrylonitrile content 34 mass% in nitrile rubber) and 1016 g of butadiene rubber (trade name: JSR BR01, manufactured by JSR Corporation) The mixture was added and kneaded under pressure for about 3 minutes while cooling. The temperature of the mixed dough was about 80 ° C. Subsequently, 127 g of erucic acid amide (manufactured by NOF Corporation, product name: Alfro P-10), 254 g of polyethylene wax (manufactured by Clariant Co., Ltd., product name: LICOWAX PED521), silica (manufactured by Tosoh Silica Co., Ltd.) Product name: Nipsil LP) 508 g, titanium oxide (manufactured by Ishihara Sangyo Co., Ltd., product name: CR-80) 63.5 g, carbon black (manufactured by Mitsubishi Chemical Corporation, product name Dia Black SA) 2.3 g, stearic acid as lubricant 12.7 g was added and kneaded for about 3 minutes. Finally, 2.54 g of 2,5-dimethyl-2,5-di (t-butylperoxy) hexane (manufactured by NOF Corporation, trade name: Perhexa 25B-40, purity 40%) was added as a vulcanizing agent and continued. It kneaded for about 1 minute. During this period, the temperature of the kneaded product was adjusted so as not to exceed 100 ° C. The obtained kneaded material was quickly passed through a pressure roll, processed into a sheet shape, and cooled to 25 ° C. or lower to obtain a sheet-shaped mold release recovery resin composition having a thickness of 6 mm.

(Examples 2 to 12, Comparative Examples 1 to 5)
Except for the formulation shown in Table 1, the resin composition for mold release recovery of each Example and each Comparative Example was obtained in the same manner as the resin composition of Example 1.

[Evaluation]
About the mold release recovery resin composition obtained as described above, the uniformity of mold release imparting to the entire inner surface of the mold, the strength of the resin composition, and the mold release recovery operation as follows Later, the workability when removing the resin composition from the molding die was evaluated. The evaluation results are shown in Table 1. All the evaluations were performed under conditions where the internal surface temperature of the molding die was 175 ° C. In addition, the unit in each composition shown in Table 1 is a mass part, and "-" in a table | surface shows having not mix | blended.

[Evaluation test for uniformity of mold release]
PDIP-14L (8) provided with a plunger with a tip made of cemented carbide at the tip, using a commercially available biphenyl-based epoxy resin molding material (trade name: EME-7351T, manufactured by Sumitomo Bakelite Co., Ltd.) as the sealing molding. 500 shots of compression molding was performed with a pot-48 cavity mold. After performing 500 shots of molding of the sealed molded product, it was visually confirmed that dirt was generated on the inner surface of the mold.
Next, the mold was repeatedly compression molded at 175 ° C. using a mold cleaning composition (trade name: Nicaret RCC ID grade, manufactured by Nippon Carbide Industries Co., Ltd.) to remove dirt on the inner surface of the mold.
Then, mold release was imparted to the mold inner surface by compression molding at 175 ° C. using the mold release recovery resin composition.
Next, the biphenyl-based epoxy resin molding material is molded, and the mold release recovery resin composition is released by visually confirming the surface of the sealing molded product first performed after the mold release recovery operation. The homogeneity of the imparting property was evaluated. The surface of the sealed molded product was evaluated as good when there was no gloss unevenness, and when the surface was uneven, it was evaluated as impossible.

[Evaluation test of strength of resin composition]
The strength of the resin composition was evaluated as follows. After the mold release recovery work, the resin composition was removed from the mold. Next, evaluation was performed by holding both ends in the longitudinal direction of the removed resin composition with both hands and bending it 180 degrees. Resin composition is excellent when it is not broken, and some cracks are generated in the bent part, but it is good that it can be bent 180 degrees, it can be bent 180 degrees, but it can be deeply cracked, resin composition Those that could not be bent 180 degrees, such as cracked objects, were evaluated as impossible.
In addition, the magnitude | size of the resin composition which evaluates the intensity | strength of a resin composition is about 17.5 cm x 4.0 cm, and thickness is about 0.3 cm.

[Evaluation test of workability during removal from the molding die]
The workability at the time of removing the resin composition from the molding die was evaluated as follows. After mold release recovery work, the mold release recovery resin composition has no cracks and does not stick to the upper and lower surfaces of the mold, so excellent workability is excellent, and the resin composition cracks. Or, it may stick to the upper and lower surfaces of the molding die, but the one with a small degree is good, the workability is slightly reduced, but the acceptable one is acceptable, the resin composition cracks significantly, or the upper and lower surfaces of the molding die It was necessary to clean the mold again for sticking to the surface, and it was evaluated that it was impossible to remarkably deteriorate the release workability.

From the results shown in Table 1, all of the mold release recovery resin compositions according to the embodiments of the present invention were able to uniformly impart release properties to the entire inner surface of the mold. Moreover, the surface of the sealing molded product (epoxy resin molding material) molded immediately after the mold release recovery operation had no gloss unevenness and had a good appearance. Further, the mold release recovery resin composition of the present invention has high strength, and the mold release recovery operation does not crack the resin composition and does not stick to the upper and lower surfaces of the mold. The workability when removing from the mold was also good.
On the other hand, the mold release recovery resin composition according to the comparative example is not practical because the mold release property on the entire inner surface of the mold is uneven or the workability of the mold release recovery work is extremely poor. At least one defect that is not suitable is shown.

  The mold release recovery resin composition of the present invention is used after removing dirt on the inner surface of the mold generated in the molding process of the sealed molded product, so that the mold release property is uniform over the entire inner surface of the mold. Can be granted.

Claims (3)

Unsaturated fatty acid having a content of 1 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the synthetic rubber, the vulcanizing agent, and the synthetic rubber having an acrylonitrile content of 1 to 50% by mass. A mold release recovery resin composition comprising an amide.   The mold release recovery resin composition according to claim 1, wherein the unsaturated fatty acid amide is at least one selected from the group consisting of erucic acid amide, oleic acid amide, and nervonic acid amide. Mold release recovery method using a mold release recovery resin composition according to any one of claims 1-2.