JPWO2009057479A1 - Rubber composition for mold cleaning - Google Patents

Abstract

In the rubber composition for mold cleaning for removing dirt on the mold surface generated in the molding process of the curable resin, the blending ratio of ethylene-propylene rubber and butadiene rubber is 90/10 to 10 as the base resin. An unvulcanized rubber set to 50/50 parts by weight, having an elongation of 80 to 800% after vulcanization and curing of the unvulcanized rubber, a tensile strength of 3 to 10 MPa, a rubber hardness (durometer hardness) S) is A60 to 95, 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C., and unvulcanized rubber having a value in the range of 50 to 100 seconds or 200 to 400 seconds is used. To do. When used for cleaning a small package manufacturing die having a deep cavity, such as PDIP or SOIC, or a small package manufacturing die having a small number of pins, among other small packages, tc (90) is It is preferable to include a release agent together with the unvulcanized rubber in the range of 200 to 400 seconds.

Description

  The present invention relates to a rubber composition for mold cleaning, and more particularly, as a base resin in a mold cleaning resin composition for removing dirt on a mold surface generated in a molding process of a curable resin. The present invention relates to a rubber composition for mold cleaning, characterized by using an unvulcanized rubber.

Conventionally, when molding a molded product such as an integrated circuit with a thermosetting resin such as an epoxy resin, if the molding is continued for a long time, the inner surface of the mold becomes soiled. In many cases, the molding operation cannot be continued because the surface becomes dirty or the sealed molding adheres to the mold. Therefore, it is necessary to periodically clean the mold, and a method of cleaning the mold by molding a mold cleaning resin at a rate of several shots every time hundreds of molding materials are molded has been proposed. Japanese Patent Publication No. 52-788 discloses a method of cleaning a mold by molding a resin composition for mold cleaning comprising an amino resin, an organic base material and / or an inorganic base material, and a release agent. Has been.
On the other hand, in place of the thermosetting melamine resin molding material, an unvulcanized rubber compound containing a cleaning component is used, which is present on the mold surface when vulcanized in a mold to form a vulcanized rubber. A method has been proposed in which an oxidatively deteriorated layer such as a release agent is decomposed by a cleaning component and integrated with a vulcanized rubber, and then the mold surface is cleaned by removing the vulcanized rubber from the mold. Further, as an unvulcanized rubber component, a rubber-based composition in which a butadiene rubber / ethylene-propylene rubber component is set to 90/10 to 50/50 parts by weight has also been proposed (for example, JP-A-63-227308, JP-A-4-357007).

Mold cleaning materials can be broadly divided into two types: transfer type and compression type. The transfer type uses melamine resin molding material, and the compression type uses melamine resin molding material and rubber cleaning. The material is used.
In recent years, with the integration, thinning, and surface mounting of integrated circuits and the like (abbreviated as IC / LSI), the shape and structure of molded products have been diversified. Fluidization and environmental measures are being planned.
For this reason, in the high fluidization type epoxy sealing material, resin clogging at the air vent part is likely to occur, and when these clogging occurs, the air does not escape well and the resin does not flow, so the cavity part is not filled. Since it becomes defective, continuous molding becomes difficult. Therefore, in order to avoid these situations, it is necessary to carry out cleaning. However, with the transfer type cleaning material, it is difficult to remove the resin clogged in the air vent because the resin does not flow normally for the reasons described above. It was.

  Compression type cleaning materials are used to eliminate such clogging of the air vents, but when melamine resin molding materials are used, clogging of the air vent part is eliminated, but the vicinity of the mold periphery is caused by the outflow of resin. Since the pressure is not sufficiently applied, the outer peripheral portion of the molded product tends to become brittle, and the work of removing the cured molded product from the mold is complicated. On the other hand, when a rubber-based cleaning material is used, the entire cleaning material is uniformly cured and can be released from the mold as a single sheet-like molded product, so that workability is improved. However, since the rubber-based cleaning material is worse than the melamine-based resin molding material in terms of fluidity, there is a problem that the filling property into the cavity is poor and dirt such as the cavity corner cannot be removed.

  In addition, the number of pins is small even in small package manufacturing molds such as Plastic Dual Inline Package (hereinafter abbreviated as PDIP) and Small Outline Integrated Circuit (hereinafter abbreviated as SOIC). When a rubber-based cleaning material is used in a small number of molds for manufacturing a package, since the number of packages is increased, a phenomenon that a molded product after curing sticks to the mold tends to occur. When removing this, there is a problem that the sheet-like molded product is broken and chipping occurs in which the rubber-based cleaning material remains in the cavity. When chipping occurs in these molds, since the number of cavities is large, it takes a lot of time to remove the molded product at the chipping location.

  In order to solve the above problems, workability (releasability) and moldability are excellent and there is no unfilling at the corner of the cavity, and there is a phenomenon such as chipping at the time of mold release due to elongation and high strength. There is a need for rubber-based cleaning materials that do not occur.

Japanese Patent Publication No.52-788 JP-A-63-227308 JP 04-357007 A

As described above, the present invention eliminates the drawbacks of conventional rubber-based cleaning materials that cause voids and chipping, but has good workability (releasability), and does not cause voids or chipping. It is an issue to provide.
In addition, the present invention is a conventional rubber system that has good workability (releasability) but does not generate voids or chipping, or does not generate voids but has poor workability (releasability) and chipping. In addition to eliminating defects in cleaning materials, voids and chipping can be achieved even in small package manufacturing molds with deep cavities such as PDIP and SOIC, and even in small package manufacturing molds with a small number of pins. It is an object of the present invention to provide a rubber-based cleaning material that does not generate water.

This invention solves the said subject by providing the rubber-type composition for metal mold | die cleaning of following (1), (2) and (3).
(1) In the mold cleaning resin composition for removing dirt on the mold surface generated in the molding step of the curable resin, the blending ratio of ethylene-propylene rubber and butadiene rubber as the base resin is 90 / Using unvulcanized rubber set to 10-50 / 50 parts by weight, and the unvulcanized rubber has an elongation of 80 to 800% after vulcanization and curing, and a tensile strength of 3 to 10 MPa, A metal having a rubber hardness (durometer hardness) of A60 to 95 and a 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C. in a range of 50 to 100 seconds. Rubber composition for mold cleaning. (Hereinafter referred to as the first mold cleaning rubber-based composition)
(2) In the mold cleaning resin composition for removing dirt on the mold surface generated in the molding step of the curable resin, the blending ratio of ethylene-propylene rubber and butadiene rubber as the base resin is 90 / Using unvulcanized rubber set to 10-50 / 50 parts by weight, and the unvulcanized rubber has an elongation of 80 to 800% after vulcanization and curing, and a tensile strength of 3 to 10 MPa, Metal having a rubber hardness (durometer hardness) of A60 to 95 and a 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C. in a range of 200 to 400 seconds Rubber composition for mold cleaning. (Hereinafter referred to as the second rubber cleaning composition for mold cleaning)
(3) In the mold cleaning resin composition for removing dirt on the mold surface generated in the molding step of the curable resin, the blending ratio of ethylene-propylene rubber and butadiene rubber as the base resin is 90 / Using unvulcanized rubber set to 10-50 / 50 parts by weight, and the unvulcanized rubber has an elongation of 80 to 800% after vulcanization and curing, and a tensile strength of 3 to 10 MPa, It is an unvulcanized rubber having a rubber hardness (durometer hardness) of A60 to 95 and a 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C. within a range of 200 to 400 seconds. And the rubber-type composition for metal mold | die cleaning characterized by containing at least 1 sort (s) of mold release agent. (Hereinafter referred to as the third rubber cleaning composition for mold cleaning)
The rubber compositions for cleaning the first, second and third molds of the present invention are excellent not only in workability (mold release property) but also in moldability and strength, and consequently no generation of voids and chipping. is there.

In the first, second and third mold cleaning rubber-based compositions of the present invention, the unvulcanized rubber used as the base resin has an elongation of 80 to 800% after vulcanization and curing, and a tensile strength. 3 to 10 MPa, rubber hardness (durometer hardness) A60 to 95, 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C., a value of 50 to 100 seconds or 200 to 400 seconds As a result, the air vent part can be easily cleaned, and the rubber-based composition has excellent moldability and strength while maintaining the workability (peelability) characteristic of rubber-based cleaning materials. It is a thing.
In addition, the third mold cleaning rubber composition of the present invention contains at least one mold release agent, so that a small mold for manufacturing a package having a deep cavity such as PDIP or SOIC, Among small packages, the rubber composition is suitable for cleaning a mold for manufacturing a small package with a small number of pins.

Hereinafter, first, the first rubber cleaning composition for mold cleaning of the present invention will be described in detail.
The unvulcanized rubber used in the present invention is a mixture of ethylene-propylene rubber and butadiene rubber.
Ethylene-propylene rubber (hereinafter sometimes abbreviated as EPM) is intended to include both ordinary ethylene-propylene rubber (EPM) and ethylene-propylene-diene rubber (hereinafter sometimes abbreviated as EPDM). is there.

As said EPM, the copolymerization ratio of ethylene and α-olefin (particularly propylene) is ethylene / α-olefin = 55/45 to 83/17 in molar ratio, and Mooney viscosity ML _{1 + 4} (100 ° C.) is 5 to 300. In particular, the copolymerization ratio is such that the molar ratio ethylene / α-olefin = 55/45 to 61/39 and the Mooney viscosity ML _{1 + 4} (100 ° C.) is 36 to 44.

The EPDM is a terpolymer composed of ethylene, α-olefin, and a cyclic or non-cyclic product having a nonconjugated double bond. More specifically, it is a terpolymer composed of ethylene, an α-olefin (particularly propylene), and a polyene monomer.
Examples of the polyene monomer include dicyclopentadiene, 5-cyclooctadiene, 1,7-cyclododecadiene, 1,5,9-cyclododecatriene, 1,4-cycloheptadiene, 1,4-cyclohexadiene, norbornadiene. Methylene norbornene, 2-methylpentadiene-1,4,1,5-hexadiene, 1,6-heptadiene, methyl-tetrahydroindene, 1,4-hexadiene and the like. The copolymerization ratio of each monomer in such a terpolymer is preferably 30 to 80 mol% for ethylene, 0.1 to 2 mol% for the polyene monomer, and the remainder being α-olefin. More preferably, ethylene is 30 to 60 mol%. And as EPDM which is the said terpolymer, it is preferable to use that whose Mooney viscosity ML1 _{+ 4} (100 degreeC) is 20-70.

The butadiene rubber (hereinafter sometimes abbreviated as BR) has a high cis structure in which the content of cis 1,4 bonds is 90% by weight or more, and has a Mooney viscosity ML _{1 + 4} (100 ° C.) of 20-60. In particular, those of 30 to 45 are preferably used.

And the compounding ratio of the said ethylene-propylene rubber and butadiene rubber is 90 / 10-50 / 50 weight part by weight ratio, Preferably it is 80 / 20-60 / 40 weight part.
When the ethylene-propylene rubber is blended in an amount exceeding 90 parts by weight, the mold releasability deteriorates and the cleaning operation time becomes long, which is not preferable. When the butadiene rubber exceeds 50 parts by weight, the mold releasability is improved, but the molded product after vulcanization is hard and brittle, so that chipping is likely to occur, which is not preferable.

The unvulcanized rubber has an elongation percentage after vulcanization and curing of 80 to 800%, preferably 100 to 300%. An elongation of 80% or less is not preferable because moldability deteriorates.
The unvulcanized rubber has a tensile strength after vulcanization and curing of 3 to 10 MPa, preferably 5 to 8 MPa. If the tensile strength is 3 MPa or less, chipping occurs, which is not preferable.
The unvulcanized rubber has a rubber hardness (durometer hardness) of A60 to 95, preferably A70 to 90 after vulcanization and curing. If the rubber hardness deviates from this range, chipping and voids are generated, which is not preferable.
The unvulcanized rubber has a 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C. for 50 to 100 seconds, preferably 70 to 100 seconds. If the value of tc (90) is within this range, the vulcanization rate will not be too fast and the resin can be filled to every corner of the cavity, so cleaning is performed without causing problems such as sticking. I can do it. In addition, since cleaning can be performed with a more efficient curing time compared to conventional rubber-based cleaning materials, the total cleaning time can be reduced.

  The rubber-based composition of the present invention contains a filler, a cleaning agent, a cleaning aid, a vulcanizing agent, a vulcanization aid, a vulcanization accelerator, a vulcanization acceleration aid, etc. in addition to the unvulcanized rubber. can do.

Examples of the filler (reinforcing agent) include silica, alumina, calcium carbonate, aluminum hydroxide, and titanium oxide. The amount of the filler used is preferably 10 to 70 parts by weight, more preferably 30 to 60 parts by weight with respect to 100 parts by weight of the unvulcanized rubber.
Examples of the cleaning agent include amines such as monoethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N, N-di-n-butylethanolamine, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, etc. Glycol ethers, imidazoles and imidazolines. The amount of the cleaning agent used is preferably 5 to 50 parts by weight, more preferably 5 to 30 parts by weight with respect to 100 parts by weight of the unvulcanized rubber. In addition, a cleaning aid such as a surfactant can be used.

  Examples of the vulcanizing agent include di-t-butyl peroxide, di-t-amyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di- (t-butylperoxy) -hexane. Diallyl peroxide organic peroxides such as 1,1-bis (t-butylperoxy) 3,3,5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, 2, Peroxyketals such as 2-bis (t-butylperoxy) octane, n-butyl-4,4-bis (t-butylperoxy) valerate, 2,2-bis (t-butylperoxy) butane Oxides. In general, peroxyketals have a longer half-life compared to diallyl peroxides, but these may be used alone in combination with the design of the composition, and those with a longer half-life and shorter You may adjust a vulcanization speed together. The amount of the vulcanizing agent used is preferably 1 to 6 parts by weight, more preferably 2 to 4 parts by weight with respect to 100 parts by weight of the unvulcanized rubber. In addition, vulcanization aids such as acrylic acid monomers and sulfur can be used.

  Examples of the vulcanization accelerator include guanidines such as diphenylguanidine and triphenylguanidine, for example, aldehyde-amines such as formaldehyde-paratoluidine condensate, acetaldehyde-aniline reactant, and aldehyde-ammonia, such as 2- Examples thereof include thiazoles such as mercaptobenzothiazole and dibenzothiazyl disulfide, and vulcanization accelerating aids such as magnesia, risurge and lime can be used.

  In addition to these blends, the rubber composition of the present invention, if necessary, for example, petals, bitumen, iron black, ultramarine, carbon black, lithopone, titanium yellow, cobalt blue, Hansa yellow, quinacridone red, etc. Inorganic or organic pigments; for example, metal soap lubricants such as zinc stearate, zinc myristate, aluminum stearate, calcium stearate, for example, fatty acid ester lubricants such as butyl stearate, butyl laurate, stearyl stearate, Amide lubricants such as ethylene bisstearamide, erucic acid amide, oleic acid amide, stearic acid amide, and behenic acid amide can be used in combination.

Next, the second rubber cleaning composition for mold cleaning according to the present invention will be described.
In the second rubber cleaning composition of the present invention, the unvulcanized rubber used as the base resin has a 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C. Except for the point that it is an unvulcanized rubber for 200 to 400 seconds, preferably 250 to 350 seconds, it is the same as the first rubber cleaning composition for mold cleaning of the present invention.
The adjustment of the value of tc (90) can be appropriately adjusted depending on the type and amount of diene, the type and amount of peroxide, the type and amount of vulcanization accelerator, the type and amount of co-crosslinking agent, and the like.

  If the value of tc (90) of the unvulcanized rubber is in the range of 200 to 400 seconds, the vulcanization speed will not be too fast, and the rubber composition will gently follow the mold shape during mold clamping. Therefore, the resin can be filled to the corners of the cavity without generating voids. Further, the cleaning can be performed without causing problems such as sticking caused by unfilling or voids.

Next, the third mold cleaning rubber-based composition of the present invention will be described.
The third mold cleaning rubber-based composition of the present invention is obtained by adding at least one release agent to the second mold cleaning rubber-based composition of the present invention.

Examples of the release agent include metal soap release agents, fatty acid ester release agents, synthetic waxes, and fatty acid amide release agents.
Examples of the metal soap release agent include calcium stearate, zinc stearate, zinc myristate and the like. Examples of fatty acid ester release agents, synthetic waxes, and fatty acid amide release agents include Rico wax OP (Montannic acid partially saponified ester manufactured by Clariant Japan Co., Ltd.), Roxyol G-78 (polymer compound ester manufactured by Cognis Japan Co., Ltd.) ), Recolve H-4 (modified hydrocarbon manufactured by Clariant Japan Co., Ltd.), Roxyol VPN881 (mineral oil-based synthetic wax manufactured by Cognis Japan Co., Ltd.), fatty acid amide S (fatty acid amide manufactured by Kao Corporation), Kao wax EB-P (Kao) (Fatty Acid Amide, Inc.), Alfro HT-50 (Nippon Yushi Co., Ltd. Fatty Acid Amide) and the like can be exemplified.
These release agents are preferably blended in an amount of 3 to 15 parts by weight, preferably 5 to 10 parts by weight, based on 100 parts by weight of unvulcanized rubber.
When the amount of the release agent is insufficient, even in a small package with a deep cavity such as PDIP or SOIC, the number of cavities arranged on the mold is large especially in a small package manufacturing mold with a small number of pins. Therefore, mold releasability is relatively lowered. If the amount of the release agent is too large, the mold releasability is good, but the cleaning property is poor, which is not preferable.

  It does not specifically limit as a preparation method of the rubber system composition for the 1st and 2nd metal mold | die cleaning of this invention, A well-known method is employable. For example, EPM and BR dough are put into a pressure kneader with a jacket and kneading is started, and kneading is continued while observing the temperature of the dough appropriately until the mixed dough of EPM and BR becomes mochi. Then, when the temperature of the mixed dough reaches 70 to 100 ° C., white carbon, amino alcohol compound, cyclic amide compound, process oil, nonionic surfactant, stearic acid, etc. are added and kneaded for several minutes. To do. Next, an organic peroxide, sulfur and the like are added and dispersed quickly, and then taken out, and if necessary, molded into an appropriate shape such as a sheet, for example, to obtain the rubber composition for mold cleaning of the present invention.

  The third mold cleaning rubber composition of the present invention can be prepared, for example, in the above-described second mold cleaning rubber composition preparation method of the present invention by mixing EPM and BR with other materials. What is necessary is just to add the said mold release agent with this additive.

  Examples of the kneading means include a Banbury mixer, a roll mixer and the like in addition to the pressure type kneader.

  The forms of the first, second and third mold cleaning rubber-based compositions of the present invention are not particularly limited, but the kneaded resin composition can be vulcanized by preheating during kneading unless it is cooled quickly. Since it is promoted and stable performance cannot be obtained, the rubber composition for mold cleaning of the present invention is preferably in the form of a sheet that can be easily cooled in a short time.

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Test Method Test methods for evaluating various physical properties described in Examples and Comparative Examples are as follows.
[Elongation rate and tensile strength]
Measured in accordance with the measurement method of tensile strength and elongation at break in JIS K6251.
<Test specimen preparation conditions>
Using a 37T automatic press, an unvulcanized sample is molded at a mold temperature of 175 ° C., a molding pressure of 10 MPa (gauge pressure), and a molding time of 5 minutes. The size of the molded specimen was 80 × 160 × 2 mm, and this was punched out with a No. 3 dumbbell to obtain a test specimen for measurement.

[Rubber hardness]
It is measured by a method in accordance with JIS K6253 “Method for testing hardness of vulcanized rubber and thermoplastic rubber”.
Three 80 × 160 × 2 mm test pieces obtained under the test piece preparation conditions described above were stacked, and the durometer hardness was measured using a durometer of a type corresponding to the rubber hardness.

[Vulcanization speed]
Measure 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C using a method based on JIS K6300-2 “How to determine vulcanization characteristics using a vibration vulcanization tester” did.

[Cleanability test]
Using a commercially available biphenyl-based epoxy resin molding material (EME-7351T manufactured by Sumitomo Bakelite Co., Ltd.), the mold was soiled by molding 500 shots with a PDIP-14L (8 pot-48 cavity) mold. Evaluation was performed by repeatedly molding the mold cleaning resin composition using the soiled mold until the mold surface was cleaned cleanly. In Examples 9 to 12, evaluation was performed using a PDIP-8L (8 pot-96 cavity) mold.

Example 1 (first rubber cleaning composition for mold cleaning of the present invention)
1050 g of EPDM fabric [Mooney viscosity ML _{1 + 4} (100 ° C. 23)] in a 3000 ml jacketed pressure kneader and BR fabric [Mooney viscosity ML _{1 + 4} (100 ° C.) 42, 1,4 cis bond content 95% by weight When 450 g was added and pressure-kneaded for about 3 minutes while cooling, the EPDM and BR mixed dough became sticky and its temperature was about 80 ° C. Next, 150 g of monoethanolamine (10 parts by weight with respect to 100 parts by weight of EPDM and BR mixed dough), 75 g of polyoxyalkylene decyl ether surfactant (5 parts by weight), 15 g of stearic acid (1 part by weight), White carbon 750 g (50 parts by weight), calcium carbonate 75 g (5 parts by weight), titanium oxide 75 g (5 parts by weight) and zinc oxide 75 g (5 parts by weight) were added and kneaded for about 3 minutes. Finally, 48 g (3.2 parts by weight) of 1,1-bis (t-butylperoxy) cyclohexane was added and 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 rubber composition A for sheet-shaped mold cleaning having a thickness of 6 mm.
Table 1 shows the characteristic values and the cleaning property test results of the obtained rubber composition A for cleaning a sheet-like mold. As can be seen from the test results, the rubber composition A for sheet-shaped mold cleaning showed good cleaning properties.

Example 2 (first rubber cleaning composition for mold cleaning of the present invention)
In Example 1, the blending amount of the base resin was EPDM fabric [Mooney viscosity ML _{1 + 4} (100 ° C.) 23] 900 g and BR fabric [Mooney viscosity ML _{1 + 4} (100 ° C.) 42, 1,4 cis bond content 95% by weight] Except for changing to 600 g, a rubber composition B for sheet-shaped mold cleaning having a thickness of 6 mm was obtained in the same manner.
Table 1 shows the characteristic values and the cleaning property test results of the obtained rubber composition B for cleaning a sheet-like mold. As can be seen from the test results, the rubber composition B for sheet-shaped mold cleaning showed good cleaning properties.

Example 3 (first mold cleaning rubber-based composition of the present invention)
In Example 1, instead of 150 g of monoethanolamine (10 parts by weight with respect to 100 parts by weight of EPDM and BR mixed dough), 450 g of (±) -1-amino-2-propanol (EPDM and BR mixed dough 100) A rubber composition C for sheet-shaped mold cleaning having a thickness of 6 mm was obtained in the same manner except that 30 parts by weight) was used.
Table 1 shows the characteristic values and the cleaning property test results of the obtained rubber composition C for cleaning a sheet-like mold. As can be seen from the test results, the rubber composition C for sheet-shaped mold cleaning showed good cleaning properties.

Example 4 (first rubber cleaning composition for mold cleaning of the present invention)
In Example 1, the base resin was EPDM fabric [Mooney viscosity ML _{1 + 4} (100 ° C.) 23] 825 g and BR fabric [Mooney viscosity ML _{1 + 4} (100 ° C.) 35, 1,4 cis bond content 95% by weight. The amount of white carbon is changed from 750 g (50 parts by weight to 100 parts by weight of EPDM and BR mixed dough) to 450 g (30 parts by weight to 100 parts by weight of EPDM and BR mixed dough). A rubber composition D for sheet-shaped mold cleaning having a thickness of 6 mm was obtained in the same manner except that the weight was changed to (parts by weight).
Table 1 shows the characteristic values and cleaning property test results of the obtained rubber composition D for cleaning a sheet-like mold. As can be seen from the test results, the rubber composition D for sheet-shaped mold cleaning showed good cleaning properties.

Comparative Example 1
In Example 1, the base resin was blended in an EPDM fabric [of Mooney viscosity ML _{1 + 4} (100 ° C.) 23] 600 g and a BR fabric [Mooney viscosity ML _{1 + 4} (100 ° C.) 42, 1,4 cis bond content 95% by weight] A rubber composition E for sheet-shaped mold cleaning having a thickness of 6 mm was obtained in the same manner except that the weight was changed to 900 g.
Table 1 shows the characteristic values and the cleaning property test results of the obtained rubber composition E for cleaning a sheet-like mold. As can be seen from the test results, unfilled cavities and chipping of the mold occurred, requiring a lot of cleaning work time. Also, the cleaning property is poor, and a large number of shots are required until the cleaning is completed.

Example 5 (second rubber mold cleaning composition of the present invention)
In Example 1, instead of 48 g of 1,1-bis (t-butylperoxy) cyclohexane (3.2 parts by weight based on 100 parts by weight of EPDM and BR mixed dough), 48 g of dicumyl peroxide (EPDM and A rubber system for cleaning a sheet-like mold having a thickness of 6 mm was used in the same manner except that the kneaded material temperature was adjusted not to exceed 110 ° C. using 3.2 parts by weight of BR mixed dough. Composition F was obtained.
Table 2 shows the characteristic values and cleaning property test results of the obtained rubber composition F for cleaning a sheet-like mold. As can be seen from the test results, the rubber composition F for cleaning a sheet-like mold showed good moldability and cleanability.

Example 6 (second mold cleaning rubber composition of the present invention)
In Example 5, the blending amount of the base resin was EPDM fabric [Mooney viscosity ML _{1 + 4} (100 ° C.) 23] 900 g and BR fabric [Mooney viscosity ML _{1 + 4} (100 ° C.) 42, 1,4 cis bond content 95% by weight] Except for changing to 600 g, a rubber composition G for sheet-shaped mold cleaning having a thickness of 6 mm was obtained in the same manner.
Table 2 shows the characteristic values and the cleaning property test results of the obtained rubber composition G for cleaning a sheet-like mold. As can be seen from the test results, the rubber composition G for sheet-shaped mold cleaning showed good moldability and cleanability.

Example 7 (second rubber mold cleaning composition of the present invention)
In Example 5, instead of 150 g of monoethanolamine (10 parts by weight with respect to 100 parts by weight of EPDM and BR mixed dough), 300 g of (±) -1-amino-2-propanol (EPDM and BR mixed dough 100) 20 parts by weight), and instead of 48 g of dicumyl peroxide (3.2 parts by weight), 28 g of dicumyl peroxide (1.9 parts by weight) and n-butyl 4,4- A rubber composition H for sheet mold cleaning having a thickness of 6 mm was obtained in the same manner except that 20 g (1.3 parts by weight) of bis (t-butylperoxy) valerate was used.
Table 2 shows the characteristic values and the cleaning property test results of the obtained rubber composition H for cleaning a sheet-like mold. As can be seen from the test results, the rubber composition H for cleaning a sheet-like mold showed good moldability and cleanability.

Example 8 (second rubber mold cleaning composition of the present invention)
In Example 5, instead of the BR dough Mooney viscosity _{ML 1 + 4 (100 ℃)} 42,1,4 cis-bond content of 95 wt% of one] 450 g, BR dough Mooney viscosity _{ML 1 + 4 (100 ℃)} 35,1 , 4 cis bond content: 95% by weight], and instead of 48 g of dicumyl peroxide (3.2 parts by weight with respect to 100 parts by weight of EPDM and BR mixed dough), 1,1 -Bis (t-Butylperoxy) Sheet-like mold with a thickness of 6 mm in the same manner except that it was changed to 13 g of cyclohexane (0.9 parts by weight) and 35 g of dicumyl peroxide (2.3 parts by weight). A rubber composition I for cleaning was obtained.
Table 2 shows the characteristic values and the cleaning property test results of the obtained rubber composition I for cleaning a sheet-like mold. As can be seen from the test results, the rubber composition I for cleaning a sheet-like mold showed good moldability and cleanability.

Comparative Example 2
In Example 5, the base resin was blended in an EPDM fabric [of Mooney viscosity ML _{1 + 4} (100 ° C.) 23] 600 g and a BR fabric [Mooney viscosity ML _{1 + 4} (100 ° C.) 42, 1,4 cis bond content 95% by weight] A rubber composition J for sheet-shaped mold cleaning having a thickness of 6 mm was obtained in the same manner except that the weight was changed to 900 g.
Table 2 shows the characteristic values and cleaning test results of the obtained rubber composition J for cleaning a sheet-shaped mold. As can be seen from the test results, unfilled cavities and chipping of the mold occurred, requiring a lot of cleaning work time. Also, the cleaning property is poor, and a large number of shots are required until the cleaning is completed.

Example 9 (Third Mold Cleaning Rubber-Based Composition of the Present Invention)
1050 g of EPDM fabric [Mooney viscosity ML _{1 + 4} (100 ° C. 23)] in a 3000 ml jacketed pressure kneader and BR fabric [Mooney viscosity ML _{1 + 4} (100 ° C.) 42, 1,4 cis bond content 95% by weight When 450 g was added and pressure-kneaded for about 3 minutes while cooling, the EPDM and BR mixed dough became sticky and its temperature was about 80 ° C. Next, 150 g of monoethanolamine (10 parts by weight with respect to 100 parts by weight of EPDM and BR mixed dough), 75 g of polyoxyalkylene decyl ether surfactant (5 parts by weight), 15 g of stearic acid (1 part by weight), White carbon 650g (43 parts by weight), calcium carbonate 75g (5 parts by weight), titanium oxide 75g (5 parts by weight), zinc oxide 75g (5 parts by weight), Roxyol G-78 (manufactured by Cognis Japan Co., Ltd.) 75 g (5 parts by weight) of the polymer composite ester) and 75 g (5 parts by weight) of Recolb H-4 (modified hydrocarbon manufactured by Clariant Japan KK) were added and kneaded for about 3 minutes. Finally, 48 g (3.2 parts by weight) of dicumyl peroxide was added and the mixture was kneaded for about 1 minute. During this period, the temperature of the kneaded product was adjusted so as not to exceed 110 ° C. The obtained kneaded material was quickly passed through a pressure roll, processed into a sheet shape, and cooled to 25 ° C. or less to obtain a rubber composition K for sheet-shaped mold cleaning having a thickness of 6 mm.
Table 3 shows the characteristic values and the cleaning property test results of the obtained rubber composition K for cleaning a sheet-like mold. As can be seen from the test results, the rubber composition K for cleaning a sheet-like mold showed good moldability and cleanability.

Example 10 (Third Mold Cleaning Rubber-Based Composition of the Present Invention)
In Example 9, instead of EPDM fabric [those Mooney viscosity _{ML 1 + 4 (100 ℃)} 23], EPDM fabric [those Mooney viscosity _{ML 1 + 4 (100 ℃)} 8] with 900 g, BR dough Mooney viscosity ML _{1 + 4} (100 ° C. 42, 1,4 cis bond content 95% by weight) of 600 g and roxiol G-78 of 30 g (2 parts by weight per 100 parts by weight of EPDM and BR mixed dough) ), Recolum H-4 was changed to 15 g (1 part by weight), and a new 6 mm thick sheet mold was cleaned except that 15 g zinc stearate (1 part by weight) was newly added. A rubber-based composition L was obtained.
Table 3 shows the characteristic values and cleaning property test results of the obtained rubber composition L for cleaning a sheet-like mold. As can be seen from the test results, the rubber composition L for cleaning a sheet-like mold showed good moldability and cleanability.

Example 11
In Example 9, the amount of white carbon was changed to 700 g (47 parts by weight with respect to 100 parts by weight of EPDM and BR mixed dough), and the amount of roxiol G-78 was changed to 45 g (3 parts by weight). Instead of using 75 g (5 parts by weight) of H-4, 30 g (2 parts by weight) of fatty acid amide S (Fatty Acid Amide manufactured by Kao Corporation) was added, and 75 g of zinc stearate (5 parts by weight) was newly added. , Except that 48 g (3.2 parts by weight) of 2,5-dimethyl-2,5-di-t-butylperoxyhexane was used instead of 48 g (3.2 parts by weight) of dicumyl peroxide. Thus, a rubber-based composition M for cleaning a sheet-like mold having a thickness of 6 mm was obtained.
Table 3 shows the characteristic values and the cleaning property test results of the obtained rubber composition M for cleaning a sheet-like mold. As can be seen from the test results, the rubber composition M for cleaning a sheet-like mold showed good moldability and cleanability.

Example 12
In Example 10, instead of 600 g of BR dough [Mooney viscosity ML _{1 + 4} (100 ° C.) 42, 1,4 cis bond content 95% by weight] 600 g, BR dough [Mooney viscosity ML _{1 + 4} (100 ° C.) 35, 1 , 4-cis bond content 95% by weight] is changed to 600 g, and 700 g (47 parts by weight) instead of 650 g of white carbon (43 parts by weight), and 30 g of zinc stearate (2 parts by weight). Instead of 75 g (5 parts by weight), Roxyol G-78 30 g (2 parts by weight) instead of 60 g (4 parts by weight), Dicumyl peroxide 48 g (3.2 parts by weight) In the same manner, except that 48 g (3.2 parts by weight) of di (t-butylperoxy) -m-diisopropylbenzene was used, a rubber composition N for sheet-shaped mold cleaning having a thickness of 6 mm was obtained. .
Table 3 shows the characteristic values and the cleaning property test results of the obtained rubber composition N for cleaning a sheet-like mold. As can be seen from the test results, the rubber composition N for cleaning a sheet-like mold showed good moldability and cleanability.

  As described above, the blending ratio of the ethylene-propylene rubber and the butadiene rubber is an unvulcanized rubber set to 90/10 to 50/50 parts by weight, and the elongation after vulcanization curing is 80 to 800%, tensile strength of 3 to 10 MPa, rubber hardness (durometer hardness) of A60 to 95, 90% vulcanization time (appropriate vulcanization point) at mold temperature of 175 ° C. tC (90) of 50 to 100 seconds or 200 By using a rubber composition for mold cleaning using unvulcanized rubber showing a value of up to 400 seconds, workability (peelability) is good, there is no generation of chipping or voids, cavity, runner, gate In addition to dirt, it was possible to easily remove dirt from the air vent and mold parting area.

  Among the rubber compositions for mold cleaning of the present invention, in particular, the third rubber composition for mold cleaning of the present invention contains a mold release agent, so that a cavity such as PDIP or SOIC has a cavity. It is suitable for the cleaning of deep and small package manufacturing molds, and particularly small package manufacturing molds having a small number of pins among small packages.

Claims (8)

  In the mold cleaning resin composition for removing mold surface contamination generated in the molding step of the curable resin, the blending ratio of ethylene-propylene rubber and butadiene rubber as the base resin is 90 / 10-50. / Unweighted rubber set at 50 parts by weight is used, and the unvulcanized rubber has an elongation rate of 80 to 800% after vulcanization and curing, a tensile strength of 3 to 10 MPa, rubber hardness ( Durometer hardness: A60-95, 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C. is in the range of 50-100 seconds. Rubber composition.   In the mold cleaning resin composition for removing mold surface contamination generated in the molding step of the curable resin, the blending ratio of ethylene-propylene rubber and butadiene rubber as the base resin is 90 / 10-50. / Unweighted rubber set at 50 parts by weight is used, and the unvulcanized rubber has an elongation rate of 80 to 800% after vulcanization and curing, a tensile strength of 3 to 10 MPa, rubber hardness ( Durometer hardness) is A60 to 95, 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C. is in the range of 200 to 400 seconds. Rubber composition.   In the mold cleaning resin composition for removing mold surface contamination generated in the molding step of the curable resin, the blending ratio of ethylene-propylene rubber and butadiene rubber as the base resin is 90 / 10-50. / Unweighted rubber set at 50 parts by weight is used, and the unvulcanized rubber has an elongation rate of 80 to 800% after vulcanization and curing, a tensile strength of 3 to 10 MPa, rubber hardness ( Durometer hardness) is A60 to 95, 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C., and an unvulcanized rubber having a value in the range of 200 to 400 seconds; A rubber composition for mold cleaning, comprising at least one release agent.   The rubber for mold cleaning according to claim 3, wherein the blending ratio of the base resin and the release agent is 3 to 15 parts by weight with respect to 100 parts by weight of the base resin. System composition.   The rubber composition for mold cleaning according to any one of claims 1 to 4, wherein a blending ratio of the ethylene-propylene rubber and butadiene rubber is set to 80/20 to 60/40 parts by weight. object.   The rubber composition for mold cleaning according to any one of claims 1 to 5, which is a compression type.   Furthermore, any one of Claims 1-6 containing at least 1 sort (s) of a filler, a cleaning agent, a cleaning auxiliary agent, a vulcanizing agent, a vulcanization auxiliary agent, a vulcanization accelerator, and a vulcanization acceleration auxiliary agent. The rubber composition for mold cleaning as described in 2.   A mold cleaning method using the rubber composition for mold cleaning according to any one of claims 1 to 7.