TWI428384B - Rubber-based compositions for mold cleaning - Google Patents

Description

Rubber compound for mold cleaning

The present invention relates to a rubber composition for cleaning a mold, and more particularly to a resin composition for cleaning a mold for removing dirt on a surface of a mold which is formed in a molding step of a curable resin, characterized in that: The resin is a specific unvulcanized rubber.

In the past, when a molded article such as an integrated circuit is molded by a thermosetting resin such as an epoxy resin, there are many cases where the inner surface of the mold is contaminated if it is molded for a long period of time, and if it continues in this state When the molding is continued, the surface of the sealed molded article may be contaminated, or the sealed molded article may adhere to the mold, and the forming operation may not proceed. Therefore, it is necessary to periodically clean the mold, and it is proposed to mold the mold cleaning resin in a number of times by molding the molding material several times, for example, in Japanese Patent Publication No. 52- Japanese Laid-Open Patent Publication No. 788 discloses a method of cleaning a mold by molding a resin composition for mold cleaning comprising an amine-based resin, an organic substrate, and/or an inorganic substrate and a release agent.

On the other hand, there has been proposed a method in which, when an unvulcanized rubber-based compound containing a cleaning component is used instead of the above-mentioned thermosetting melamine resin molding material, and vulcanized in a mold to vulcanize rubber, the mold is present on the surface of the mold. The oxidative degradation layer of the agent or the like is decomposed by the cleaning component and integrated with the vulcanized rubber, and then the vulcanized rubber is taken out from the mold, thereby cleaning the surface of the mold. In addition, as the unvulcanized rubber component, a rubber-based composition having a butadiene rubber/ethylene-propylene rubber component of 90/10 to 50/50 parts by weight has been proposed (for example, refer to Japanese Patent Laid-Open Publication No. SHO63-227308 Japanese Patent Laid-Open No. Hei 4-357007).

The cleaning material for the mold can be roughly classified into two types, a transfer type and a compression type, a melamine resin molding material for the transfer type, and a melamine resin molding material and a rubber type cleaning material for the compression type.

In recent years, with the increase in the size, thickness, and surface encapsulation of integrated circuits (abbreviated as IC.LSI), the shape and structure of molded products have been diversified. Therefore, manufacturers are seeking high semiconductor sealing materials. Mobility and environmental correspondence.

Therefore, the highly fluidized epoxy sealing material tends to cause clogging of the resin in the vent portion, and if such clogging occurs, the venting property is poor and the resin does not flow, so that it becomes unsatisfactory due to unfilling in the cavity portion. This makes continuous forming difficult. Therefore, in order to avoid such a situation, it is necessary to perform cleaning. However, in the case of the transfer type cleaning material, the resin does not flow normally due to the above reasons, and thus it is difficult to remove the resin blocked in the vent hole.

In order to eliminate the clogging of the vent hole as described above, the use of the condensed cleaning material, if the melamine resin molding material is used, the clogging of the vent hole portion is eliminated, but the pressure is not sufficiently applied in the vicinity of the outer periphery of the mold. The tendency of the outer peripheral portion of the molded article to become brittle is complicated by the work of removing the molded product after hardening from the mold. In the case where a rubber-based cleaning material is used in this manner, the cleaning material is cured in the same manner as a whole, and a sheet-like formed product can be produced, and the mold can be released from the mold, so that workability is improved. However, in terms of fluidity, the rubber-based cleaning material is inferior to the melamine-based resin molding material, so that the filling property in the cavity is poor, and the dirt such as the cavity angle is not removed.

In addition, in the case of a Plastic Dual Inline Package (hereinafter referred to as PDIP) or a Small Outline Integrated Circuit (hereinafter, a small outline integrated circuit, hereinafter abbreviated as SOIC), a mold for a small package is used. In the case of using a rubber-based cleaning material in a small package manufacturing mold having a small number of pins in a small package, the number of packages is increased, so that the molded article after curing is likely to be attached to the mold. When it is removed, there is a problem that the sheet-like formed product is broken, and the rubber-based cleaning material remains in the cavity of the cavity. If debris is generated in the molds, since the number of cavities is large, it takes a lot of time to remove the molded articles at the scrap portions.

In order to solve the above problems, it is advantageous in that workability (release property) and moldability are not caused by unfilled corners of the cavity, or because of elongation and high strength, it is not broken when the mold is demolded. Rubber-based cleaning materials such as chips.

Patent Document 1: Japanese Patent Publication No. Sho 52-788

Patent Document 2: Japanese Patent Laid-Open Publication No. SHO 63-227308

Patent Document 3: Japanese Patent Laid-Open No. Hei 04-357007

An object of the present invention is to provide a rubber-based cleaning material which is excellent in workability (release property) as described above, but which eliminates the disadvantages of conventional rubber-based cleaning materials which generate voids or chips without voids or breakage. Chips.

Further, an object of the present invention is to provide a rubber-based cleaning material which is excellent in workability (release property), but which not only eliminates voids or chips, but also does not generate voids, but has poor workability (release property). It is a disadvantage of the conventional rubber-based cleaning material which generates debris, and is not used in a small-sized package manufacturing mold such as a PDIP or SOIC, or a small-sized package manufacturing mold having a small number of pins in a small package. Will create voids or debris.

The present invention solves the above problems by providing the rubber-based composition for mold cleaning of the following (1), (2), and (3).

(1) A rubber-based composition for cleaning a mold for removing dirt on a surface of a mold which is formed in a step of forming a curable resin, characterized in that the base resin is made of ethylene-propylene rubber and diced The blending ratio of the olefin rubber is set to 90/10 to 50/50 parts by weight of the unvulcanized rubber, and the elongation of the unvulcanized rubber after vulcanization and hardening is 80 to 800%, the tensile strength is 3 to 10 MPa, and the rubber hardness ( The hardness of the durometer is a range of values of 50 to 100 seconds at 90% of the vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of A60 to 95 and 175 °C. (Hereinafter, it is called the rubber composition for the first mold cleaning)

(2) A rubber-based composition for cleaning a mold for removing dirt on a surface of a mold which is formed in a step of forming a curable resin, characterized in that the base resin is made of ethylene-propylene rubber and diced The blending ratio of the olefin rubber is set to 90/10 to 50/50 parts by weight of the unvulcanized rubber, and the elongation of the unvulcanized rubber after vulcanization and hardening is 80 to 800%, the tensile strength is 3 to 10 MPa, and the rubber hardness ( The hardness of the durometer is a range of values of 200 to 400 seconds at a mold temperature of A60 to 95 and a mold temperature of 175 ° C (the appropriate vulcanization point) tc (90). (hereinafter, referred to as a second rubber composition for cleaning a mold)

(3) A rubber-based composition for cleaning a mold for removing dirt on a surface of a mold which is formed in a step of forming a curable resin, characterized in that the base resin is made of ethylene-propylene rubber and diced The blending ratio of the olefin rubber is set to 90/10 to 50/50 parts by weight of the unvulcanized rubber, and the unvulcanized rubber has an elongation ratio after vulcanization and hardening of 80 to 800%, a tensile strength of 3 to 10 MPa, and rubber. The hardness (hardness tester hardness) is a range of a value of 200 to 400 seconds at a mold temperature of A60 to 95 and a mold temperature of 175 ° C (the appropriate vulcanization point) tc (90) is 200 to 400 seconds, and the rubber combination for mold cleaning is used. The material contains at least one release agent. (hereinafter, referred to as a third rubber composition for cleaning a mold)

The rubber-based composition for cleaning the first, second, and third molds of the present invention is excellent in workability (release property), excellent in moldability and strength, and does not cause voids or chipping.

The rubber-based composition for cleaning the first, second, and third molds of the present invention is a rubber-based composition in which an unvulcanized rubber used as a base resin is cured in a range of 80 to 800% after stretching and stretching. The strength is 3~10MPa, the rubber hardness (hardness hardness) is A60~95, 90% vulcanization time (appropriate vulcanization point) at the mold temperature of 175°C, tc(90) is 50~100 seconds or 200~400 seconds. As a result, the vent hole portion is easily cleaned, and the workability (peelability) of the rubber-based cleaning material is maintained, and the moldability and strength are also excellent.

In addition, the rubber composition for cleaning a third mold of the present invention is suitable for use in a mold for small package manufacturing such as PDIP or SOIC, or in a small package by containing at least one release agent. A rubber composition which is clean, which is small, and which is particularly small in packaging manufacturing molds.

Hereinafter, the first rubber composition for mold cleaning of the present invention will be described in detail first.

The unvulcanized rubber used in the present invention is a mixture of an ethylene-propylene rubber and a butadiene rubber.

The ethylene-propylene rubber (hereinafter sometimes abbreviated as EPM) includes both ordinary ethylene-propylene rubber (EPM) and ethylene-propylene-diene rubber (hereinafter sometimes abbreviated as EPDM).

As the above EPM, it is preferred that the copolymerization ratio of ethylene to an α-olefin (especially propylene) is ethylene/α-olefin = 55/45 to 83/17 in terms of a molar ratio, and the Mona viscosity ML ₁₊₄ (100 ° C) is 5 to 300, especially preferably, the above copolymerization ratio is ethylene/α-olefin = 55/45 to 61/39 in terms of molar ratio, and Mengna viscosity ML ₁₊₄ (100 ° C) It is 36~44.

Further, the above EPDM is a terpolymer formed of ethylene, an α-olefin, a ring having a non-conjugated double bond, or an acyclic substance. Specifically, it is a terpolymer formed of ethylene, an α-olefin (especially propylene), and a polyolefin monomer.

Examples of the above polyene monomer include dicyclopentadiene; 5-cyclooctadiene; 1,7-cyclododecadiene; 1,5,9-cyclododecanetriene; 1,4 -cycloheptadiene; 1,4-cyclohexadiene; Diene Alkene; 2-methylpentadiene-1,4,1,5-hexadiene; 1,6-heptadiene; methyltetrahydroanthracene; 1,4-hexadiene. The copolymerization ratio of each of the above terpolymers is preferably from 30 to 80 mol% of ethylene, from 0.1 to 2 mol% of the monomer of the polyolefin, and the balance is α-olefin. More preferably, the ethylene is 30 to 60 mol%. Further, as the above-mentioned ternary copolymer EPDM, it is preferred to use a Mona viscosity ML ₁₊₄ (100 ° C) of 20 to 70.

Further, as the butadiene rubber (hereinafter abbreviated as BR), a high cis structure having a content of a cis 1,4 bond of 90% by weight or more is preferably used, and a Mona viscosity ML ₁₊₄ (100 ° C) is 20~60, especially 30~45.

Further, the ratio of the ethylene-propylene rubber to the butadiene rubber is from 90/10 to 50/50 parts by weight, preferably from 80/20 to 60/40 parts by weight.

When the ethylene-propylene rubber is blended in an amount of more than 90 parts by weight, the mold release property is deteriorated, and the cleaning operation time becomes long, which is not preferable. When the butadiene rubber is blended in an amount of more than 50 parts by weight, the mold release property is improved, but the molded product after vulcanization becomes hard and brittle, so that chipping is liable to occur, which is not preferable.

The unvulcanized rubber has an elongation after vulcanization and hardening of 80 to 800%, preferably 100 to 300%. When the elongation is 80% or less, the formability is deteriorated, which is not preferable.

The unvulcanized rubber has a tensile strength after vulcanization and hardening of 3 to 10 MPa, preferably 5 to 8 MPa. When the tensile strength is 3 MPa or less, chipping is likely to occur, which is not preferable.

The rubber hardness (hardness hardness) after the vulcanization of the unvulcanized rubber is A60 to 95, preferably A70 to 90. If the rubber hardness is out of this range, it is liable to generate chips or voids, which is not preferable.

The unvulcanized rubber has a 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C of 50 to 100 seconds, preferably 70 to 100 seconds. If the value of tc (90) is within this range, the vulcanization rate is not too fast, and the resin can be filled into the corners of the cavity, and cleaning can be performed without causing problems such as adhesion. Moreover, compared with the conventional rubber-based cleaning material, the cleaning can be performed in an efficient hardening time, thereby reducing the overall cleaning time.

The rubber-based composition of the present invention may contain a filler, a cleaning agent, a cleaning aid, a vulcanizing agent, a vulcanization aid, a vulcanization accelerator, a vulcanization accelerating aid, etc., in addition to the above-mentioned unvulcanized rubber.

Examples of the filler (reinforcing agent) include cerium oxide, aluminum oxide, calcium carbonate, aluminum hydroxide, and titanium oxide. The amount of the filler to be used is preferably from 10 to 70 parts by weight, more preferably from 30 to 60 parts by weight, per 100 parts by weight of the unvulcanized rubber.

Examples of the cleaning agent include amines such as monoethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, and N,N-di-n-butylethanolamine; ethylene glycol dimethyl ether and diethylene glycol dimethyl glycol; a glycol ether such as ether or triethylene glycol dimethyl ether; an imidazole and an imidazoline. The amount of the cleaning agent used is preferably 5 to 50 parts by weight, more preferably 5 to 30 parts by weight, per 100 parts by weight of the unvulcanized rubber. In addition to this, a cleaning aid such as a surfactant can be used.

As the vulcanizing agent, for example, di-tert-butyl peroxide, di-third amyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di-(third a diallyl peroxide-based organic peroxide such as butyl peroxy)-hexane; for example, 1,1-bis(t-butylperoxy) 3,3,5-trimethylcyclohexane, 1 , 1-bis(t-butylperoxy)cyclohexane, 2,2-bis(t-butylperoxy)octane, 4,4-bis(t-butylperoxy)-n-butyl valerate And a peroxy ketal organic peroxide such as 2,2-bis(t-butylperoxy)butane. In general, peroxy ketals have a longer half-life than diallyl peroxides, which can be used alone depending on the design of the composition, and can be used in combination with shorter ones. To adjust the vulcanization rate. The amount of the vulcanizing agent used is preferably from 1 to 6 parts by weight, more preferably from 2 to 4 parts by weight, per 100 parts by weight of the unvulcanized rubber. In addition to this, a vulcanization aid such as an acrylic monomer or sulfur can be used.

Examples of the vulcanization accelerator include an anthracene system such as diphenylguanidine or triphenylsulfonium; for example, an aldehyde-amine system or an aldehyde-amine system such as a formaldehyde-p-toluidine condensate or an acetaldehyde-aniline reactant; for example, a 2-mercapto group; As the thiazole system such as benzothiazole or dibenzothiazyl disulfide, a vulcanization accelerating aid such as magnesium oxide, lead oxide or lime can be used.

In addition to the formulations, the rubber-based composition of the present invention may be used in combination as needed: for example, red dan, iron blue, iron black, ultramarine blue, carbon black, zinc lanthanum, titanium yellow, cobalt blue, Hansa yellow, quinquin. An inorganic or organic pigment such as acridinone; for example, a metal soap-based lubricant such as zinc stearate, zinc myristate, aluminum stearate or calcium stearate; for example, butyl stearate, butyl laurate, A fatty acid ester-based lubricant such as stearyl stearate; for example, a guanamine-based lubricant such as ethylenebisstearamide, cumylamine, ceramide, stearylamine or behenamide.

Next, the second rubber composition for cleaning a mold of the present invention will be described.

The second mold cleaning rubber composition of the present invention has a 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C which is used as a base resin, and is 200 to 400 seconds. It is preferably the same as the rubber composition of the first mold cleaning of the present invention, other than the unvulcanized rubber of 250 to 350 seconds.

The adjustment of the value of the above tc (90) can be appropriately adjusted depending on the type or amount of the diene, the kind or amount of the peroxide, the kind or amount of the vulcanization accelerator, the kind or amount of the co-crosslinking agent, and the like.

If the value of the unvulcanized rubber tc (90) is in the range of 200 to 400 seconds, the vulcanization rate is not too fast, and the rubber-based composition slowly follows the shape of the mold during the mold clamping, so that the resin can be filled to the corner of the cavity. Nothing creates gaps. Further, cleaning can be performed without causing problems such as adhesion due to unfilling or void generation.

Next, the third rubber composition for mold cleaning of the present invention will be described.

The rubber composition for mold cleaning according to the present invention is formed by including at least one release agent in the rubber composition for cleaning a second mold of the present invention.

Examples of the release agent include a metal soap-based release agent, a fatty acid ester-based release agent, a synthetic wax, and a fatty acid amide-based release agent.

Examples of the metal soap-based release agent include calcium stearate, zinc stearate, and zinc myristate. Examples of the fatty acid ester-based release agent, synthetic wax, and fatty acid amide-based release agent include: Licowax OP (manufactured by Clariant Japan Co., Ltd., partially saponified montanic acid ester), and Loxiol G-78 (Cognis Japan Co., Ltd.) Manufacture, polymer complex ester), Licolub H-4 (manufactured by Clariant Japan Co., Ltd., modified hydrocarbon), Loxiol VPN881 (manufactured by Cognis Japan Co., Ltd., mineral oil synthetic wax), Fatty Amide S (Kaowang Co., Ltd.) Manufactured, fatty acid decylamine), Kao Wax EB-P (manufactured by Kao Co., Ltd., fatty acid guanamine), Alflow HT-50 (manufactured by Nippon Oil & Fat Co., Ltd., fatty acid guanamine).

The release agent is preferably formulated in an amount of from 3 to 15 parts by weight, preferably from 5 to 10 parts by weight, based on 100 parts by weight of the unvulcanized rubber.

If the amount of the release agent is insufficient, in a small package having a deep cavity cavity such as PDIP or SOIC, the number of cavities disposed on the mold is increased in a particularly small package manufacturing mold having a small number of pins, and thus the mold is used. The release property is relatively lowered. When the amount of the releasing agent is too large, the mold release property is good, but the cleanability is deteriorated, which is not preferable.

The method for producing the rubber composition for cleaning the first and second molds of the present invention is not particularly limited, and a known method can be employed. For example, EPM and BR raw materials are put into a jacketed press kneader, and kneading is started, and while the temperature of a suitable raw material is observed, mixing is continued until the mixed raw material of EPM and BR becomes a rice cake. Further, when the temperature of the mixed raw material reaches 70 to 100 ° C, white carbon, an amino alcohol-based compound, a cyclic guanamine compound, a processing oil, a nonionic surfactant, stearic acid, or the like is added, and the number of kneading is added. minute. Then, the organic peroxide, the sulfur, and the like are added, and the mixture is quickly dispersed, taken out, and formed into a suitable shape such as a sheet shape as necessary to prepare a rubber composition for mold cleaning of the present invention.

In the preparation method of the rubber composition for cleaning a third mold of the present invention, for example, in the method for producing a rubber composition for cleaning a second mold of the present invention, the release agent is added to the EPM together with other additives. BR can be mixed in the raw materials.

As the kneading means, in addition to the above-described pressurizing type kneader, for example, a Banbury mixer, a roll mill, or the like can be mentioned.

The form of the first, second, and third mold cleaning rubber compositions of the present invention is not particularly limited, and if the kneaded resin composition is not rapidly cooled, vulcanization is promoted by preheating during kneading, and thus it is impossible to In the form of the rubber composition for mold cleaning of the present invention, it is preferably in the form of a sheet which can be easily cooled in a short period of time.

Example

The present invention will be described in more detail below by way of examples and the like, and the present invention is not limited by the examples and the like.

experiment method

The test methods for evaluation of various physical properties described in the examples and the comparative examples are as follows.

[elongation and tensile strength]

The measurement was carried out in accordance with the measurement method of tensile strength and elongation at the time of cutting in JIS K6251.

<Production conditions of test piece>

The unvulcanized sample was molded using a 37T automatic press under the conditions of a mold temperature of 175 ° C, a molding pressure of 10 MPa (measured pressure), and a molding time of 5 minutes. The formed test piece had a sheet shape of 80 × 160 × 2 mm, and was punched with a No. 3 dumbbell to prepare a test piece for measurement.

[Rubber hardness]

The measurement was carried out by a method according to JIS K6253 "Test method for hardness of vulcanized rubber and thermoplastic rubber".

Three pieces of test pieces of 80 × 160 × 2 mm obtained under the conditions of the above test piece were superposed, and the hardness of the durometer was measured using a durometer of a type conforming to rubber hardness.

[vulcanization speed]

The 90% vulcanization time (appropriate vulcanization point) tc (90) was measured at a mold temperature of 175 ° C according to JIS K6300-2 "Method for Determining Vulcanization Characteristics by Vibration Vulcanization Tester".

[Cleaning test]

Using a commercially available biphenyl-based epoxy resin molding material (manufactured by Sumitomo Bakelite Co., Ltd., EME-7351T), the mold was formed by molding 500 times in a mold of PDIP-14L (8-can-48 cavity). It is contaminated. Using the contaminated mold, the mold cleaning resin composition was repeatedly formed until the surface of the mold was cleaned, thereby being evaluated. In Examples 9 to 12, evaluation was carried out using a mold of PDIP-8L (8 cans - 96 cavity).

Example 1 (The first rubber composition for mold cleaning of the present invention)

Add 1050g of EPDM raw material to the 3000ml jacketed pressurizing kneader [Menner viscosity ML ₁₊₄ (100 °C) is 23], and 450g of BR raw material [Menna viscosity ML ₁₊₄ ( 100 ° C) is 42 and the 1,4 cis bond content is 95% by weight], and the mixture is pressurized and kneaded for about 3 minutes while cooling, and the mixed raw material of EPDM and BR is in the form of a cake, and the temperature thereof is about 80 ° C. Then, 150 g (10 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) of monoethanolamine and 75 g (5 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) were added. a stearic acid-based surfactant, 15 g (1 part by weight based on 100 parts by weight of a mixed raw material of EPDM and BR), 750 g (50 parts based on 100 parts by weight of a mixed raw material of EPDM and BR) 5 parts by weight of white carbon, 75 g (5 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR), 75 g (5 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) The titanium oxide and 75 g of zinc oxide (5 parts by weight based on 100 parts by weight of the mixed raw material of EPDM and BR) were kneaded for about 3 minutes. Finally, 48 g (3.2 parts by weight based on 100 parts by weight of the mixed raw material of EPDM and BR) of 1,1-bis(t-butylperoxy)cyclohexane was added, and kneading was continued for about 1 minute. The temperature of the kneaded material during this period was adjusted to not exceed 100 °C. The kneaded material obtained was quickly passed through a pressure roll, processed into a sheet shape, and cooled to 25 ° C or lower to obtain a sheet-like mold cleaning rubber composition A having a thickness of 6 mm.

The characteristic values and the cleanability test results of the obtained rubber-based composition A for sheet mold cleaning are shown in Table 1. According to the test results, it was found that the rubber composition A for sheet mold cleaning showed good cleanability.

Example 2 (The first rubber composition for mold cleaning of the present invention)

In Example 1, the blending amount of the base resin was changed to 900 g of EPDM raw material [Menner viscosity ML ₁₊₄ (100 ° C) was 23] and 600 g of BR raw material [Menner viscosity ML _l+4 (100) In the same manner, a sheet-like mold cleaning rubber composition B having a thickness of 6 mm was obtained in the same manner as in the case of the case where the concentration of the cis bond was 95% by weight.

The property values and the cleaning test results of the obtained rubber-based composition B for sheet mold cleaning are shown in Table 1. According to the test results, it was found that the rubber composition B for sheet mold cleaning exhibited good cleanability.

Example 3 (The first rubber composition for mold cleaning of the present invention)

In Example 1, 450 g (30 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) of (±)-1-amino-2-propanol was used instead of 150 g (relative to 100 weight). A sheet-like mold cleaning rubber composition C having a thickness of 6 mm was obtained in the same manner as in the above, except that 10 parts by weight of the monoethanolamine of the mixed raw material of the EPDM and the BR was used.

Table 1 shows the characteristic values and the cleaning test results of the obtained rubber-based composition C for sheet mold cleaning. According to the test results, it was found that the rubber composition C for sheet mold cleaning exhibited good cleanability.

Example 4 (The first rubber composition for mold cleaning of the present invention)

In Example 1, the base resin was changed to 825 g of EPDM raw material [Menner viscosity ML ₁₊₄ (100 ° C) was 23] and 675 g of BR raw material [Menner viscosity ML ₁₊₄ (100 ° C) was 35 and 1,4 cis bond content is 95% by weight], and the amount of white carbon is changed from 750 g (50 parts by weight to 100 parts by weight of the mixed raw material of EPDM and BR) to 450 g ( A sheet-like mold cleaning rubber composition D having a thickness of 6 mm was obtained in the same manner as in the above, except that it was 30 parts by weight based on 100 parts by weight of the mixed raw material of the EPDM and the BR.

The property values and the cleaning test results of the obtained rubber-based composition D for sheet mold cleaning are shown in Table 1. According to the test results, it was found that the rubber composition D for sheet mold cleaning showed good cleanability.

Comparative example 1

In Example 1, the blending amount of the base resin was changed to 600 g of EPDM raw material [Menner viscosity ML ₁₊₄ (100 ° C) was 23] and 900 g of BR raw material [Menner viscosity ML ₁₊₄ (100) In the same manner, a rubber composition E for sheet-like mold cleaning having a thickness of 6 mm was obtained in the same manner as in the case of the case where the concentration of the cis bond was 95% by weight.

The characteristic values and the cleanability test results of the obtained rubber-based composition E for sheet mold cleaning are shown in Table 1. According to the test results, it has been found that a large amount of cleaning work time is required to cause unfilling or cutting of the mold in the cavity portion. Moreover, the cleanliness is also poor, and there must be more forming times before cleaning.

Benchmark of evaluation of formability

○: The rate of unfilled production is less than 3%

△: The rate of unfilling is 3% or more and less than 10%.

×: The rate of unfilled is 10% or more

Evaluation criteria for mold release

○: The generation rate of debris is less than 3%

△: The rate of generation of debris is 3% or more and less than 10%.

×: The generation rate of debris is 10% or more

Example 5 (The second rubber composition for mold cleaning of the present invention)

In Example 1, 48 g (3.2 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) of dicumyl peroxide was used instead of 48 g (relative to 100 parts by weight of the mixture of EPDM and BR). The raw material was 3.2 parts by weight of 1,1-bis(t-butylperoxy)cyclohexane, and the temperature of the kneaded material was adjusted to not more than 110 ° C, and otherwise, a thickness of 6 mm was obtained in the same manner. The rubber-based composition F for sheet mold cleaning.

Table 2 shows the characteristic values and the cleaning test results of the obtained rubber-based composition F for sheet mold cleaning. According to the test results, it was found that the rubber composition F for sheet mold cleaning exhibited good moldability and cleanability.

Example 6 (The second rubber composition for mold cleaning of the present invention)

In Example 5, the amount of the base resin was changed to 900 g of EPDM raw material [Menner viscosity ML ₁₊₄ (100 ° C) was 23] and 600 g of BR raw material [Menner viscosity ML ₁₊₄ (100) In the same manner, a sheet-like mold cleaning rubber composition G having a thickness of 6 mm was obtained in the same manner as in the case of the case where the content of the compound was 42% and the cis bond content was 95% by weight.

Table 2 shows the characteristic values and the cleaning test results of the obtained rubber-based composition G for sheet mold cleaning. According to the test results, it was found that the rubber composition G for sheet mold cleaning exhibited good moldability and cleanability.

Example 7 (The second rubber composition for mold cleaning of the present invention)

In Example 5, 300 g (20 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) of (±)-1-amino-2-propanol was used instead of 150 g (relative to 100 weight). a mixture of EPDM and BR in an amount of 10 parts by weight of monoethanolamine, and 28 g (1.9 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) of dicumyl peroxide and 20 g ( Instead of 48 g (as opposed to 100 parts by weight of EPDM), relative to 100 parts by weight of the mixed raw material of EPDM and BR, 1.3 parts by weight of 4,4-bis(t-butylperoxy)-n-butyl valerate. A sheet-like mold cleaning rubber composition H having a thickness of 6 mm was obtained in the same manner except that 3.2 parts by weight of dicumyl peroxide was used as the mixed raw material of BR.

Table 2 shows the characteristic values and the cleaning test results of the obtained rubber-based composition H for sheet mold cleaning. According to the test results, it was found that the rubber composition H for sheet mold cleaning exhibited good moldability and cleanability.

Example 8 (The second rubber composition for mold cleaning of the present invention)

In Example 5, 450 g of BR raw material [Menner viscosity ML ₁₊₄ (100 ° C) was 42 and 1,4 cis bond content was 95% by weight] was changed to 450 g of BR raw material [Menner viscosity] ML ₁₊₄ (100 ° C) is 35 and the 1,4 cis bond content is 95% by weight], and 48 g (3.2 parts by weight based on 100 parts by weight of the mixed raw material of EPDM and BR) Dicumyl peroxide was changed to 13 g (0.9 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) of 1,1-bis(t-butylperoxy)cyclohexane and 35 g (relative to A sheet-like mold cleaning rubber composition I having a thickness of 6 mm was obtained in the same manner as in the same manner, except that the mixture of the raw materials of EPDM and BR was 2.3 parts by weight of dicumyl peroxide.

Table 2 shows the characteristic values and the cleaning test results of the obtained rubber-based composition I for sheet mold cleaning. According to the test results, it was found that the rubber composition I for sheet mold cleaning exhibited good moldability and cleanability.

Comparative example 2

In Example 5, the amount of the base resin was changed to 600 g of EPDM raw material [Menner viscosity ML ₁₊₄ (100 ° C) was 23] and 900 g of BR raw material [Menner viscosity ML ₁₊₄ (100) In the same manner, a sheet-like mold cleaning rubber composition J having a thickness of 6 mm was obtained in the same manner as in the case of the case where the temperature was at least 42 and the 1,4 cis bond content was 95% by weight.

Table 2 shows the characteristic values and the cleaning test results of the obtained rubber-based composition J for sheet mold cleaning. According to the test results, it has been found that a large amount of cleaning work time is required to produce unfilled or cut molds in the cavity portion. Moreover, the cleanliness is also poor, and there must be more forming times before cleaning.

Evaluation criteria for voids

○: The generation rate of voids is less than 3%

△: The generation rate of the void is 3% or more and less than 10%.

×: The generation rate of the void is 10% or more

Example 9 (The third rubber composition for mold cleaning of the present invention)

Add 1050g of EPDM raw material to the 3000ml jacketed pressurizing kneader [Menner viscosity ML ₁₊₄ (100 °C) is 23], and 450g of BR raw material [Menna viscosity ML ₁₊₄ ( 100 ° C) is 42 and the 1,4 cis bond content is 95% by weight], and the mixture is pressurized and kneaded for about 3 minutes while cooling, and the mixed raw material of EPDM and BR is in the form of a cake, and the temperature thereof is about 80 ° C. Then, 150 g (10 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) of monoethanolamine and 75 g (5 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) were added. a stearic acid-based surfactant, 15 g (1 part by weight based on 100 parts by weight of a mixed raw material of EPDM and BR), 650 g (compared to 100 parts by weight of a mixed raw material of EPDM and BR) 5 parts by weight of white carbon, 75 g (5 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR), 75 g (5 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) And titanium oxide, 75 g (5 parts by weight based on 100 parts by weight of the mixed raw material of EPDM and BR), and 75 g (5 parts by weight based on 100 parts by weight of the mixed raw material of EPDM and BR) Loxiol G-78 (polymer complex ester manufactured by Cognis Japan Co., Ltd.) and 75 g (5 parts by weight relative to 100 parts by weight of a mixed raw material of EPDM and BR) Licolub H-4 (Clariant Japan Co., Ltd.) The modified hydrocarbon produced) was kneaded for about 3 minutes. Finally, 48 g (3.2 parts by weight based on 100 parts by weight of the mixed raw material of EPDM and BR) of dicumyl peroxide was added, and kneading was continued for about 1 minute. The temperature of the kneaded material during this period was adjusted to not exceed 110 °C. The kneaded material obtained was quickly passed through a pressure roll, processed into a sheet shape, and cooled to 25 ° C or lower to obtain a sheet-like mold cleaning rubber composition K having a thickness of 6 mm.

The characteristic values of the obtained rubber-based composition K for sheet mold cleaning and the results of the cleaning test are shown in Table 3. According to the test results, it was found that the rubber composition K for sheet mold cleaning exhibited good moldability and cleanability.

Example 10 (The third rubber composition for mold cleaning of the present invention)

In Example 9, 900 g of EPDM raw material [Menner viscosity ML ₁₊₄ (100 ° C) was 8] was used instead of EPDM raw material [Menner viscosity ML ₁₊₄ (100 ° C) was 23], and The blending amount of the BR raw material [Menner viscosity ML ₁₊₄ (100 ° C) was 42 and the 1,4 cis bond content was 95% by weight] was changed to 600 g, and the amount of the Loxiol G-78 was changed to 30 g. (2 parts by weight based on 100 parts by weight of the mixed raw material of EPDM and BR), and the amount of Licolub H-4 is changed to 15 g (1 part by weight with respect to 100 parts by weight of the mixed raw material of EPDM and BR) In addition, 15 g of zinc stearate is added in a manner similar to 100 parts by weight of a mixed raw material of EPDM and BR, and a rubber mold combination for sheet mold cleaning having a thickness of 6 mm is obtained in the same manner. L.

Table 3 shows the characteristic values and the cleaning test results of the obtained rubber-based composition L for sheet mold cleaning. According to the test results, it was found that the rubber composition L for sheet mold cleaning exhibited 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 the mixed raw material of EPDM and BR), and the amount of the Loxiol G-78 was changed to 45 g (relative to 100). Fatty Amide S (manufactured by Kao Co., Ltd., fatty acid 醯, 30 parts by weight of the mixed raw material of EPDM and BR), using 30 g (2 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) Instead of using 75 g (5 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR), Licolub H-4, and then newly adding 75 g (relative to 100 parts by weight of the mixed raw material of EPDM and BR) 5 parts by weight of zinc stearate, and 48 g (3.2 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) of 2,5-dimethyl-2,5-di 3rd A bismuth peroxide was used instead of 48 g (3.2 parts by weight based on 100 parts by weight of the mixed raw material of EPDM and BR), and a sheet having a thickness of 6 mm was obtained in the same manner. Rubber-based composition M for mold cleaning.

The characteristic values of the obtained rubber-based composition M for sheet mold cleaning and the results of the cleaning test are shown in Table 3. According to the test results, it was found that the rubber composition M for sheet mold cleaning exhibited good moldability and cleanability.

Example 12

In Example 10, 600 g of BR raw material [Menner viscosity ML ₁₊₄ (100 ° C) was 42 and 1,4 cis bond content was 95% by weight] was changed to 600 g of BR raw material [Menner viscosity] ML ₁₊₄ (100 ° C) is 35 and the 1,4 cis bond content is 95% by weight], and 650 g (43 parts by weight based on 100 parts by weight of the mixed raw material of EPDM and BR) The white carbon is changed to 700 g (47 parts by weight with respect to 100 parts by weight of the mixed raw material of EPDM and BR) of white carbon, and 30 g (2 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) The zinc stearate is changed to 5 g (5 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) of zinc stearate, and 30 g (compared to 100 parts by weight of the mixed raw material of EPDM and BR) Moxiol G-78 in parts by weight was changed to 60 g (4 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR) of Loxiol G-78, and 48 g was used (relative to 100 parts by weight of EPDM and BR) The raw material was mixed with 3.2 parts by weight of bis(t-butylperoxy)-m-diisopropylbenzene instead of 48 g (3.2 parts by weight relative to 100 parts by weight of the mixed raw material of EPDM and BR). Diisopropylbenzene, in addition to this In addition, in the same manner to obtain a sheet having a thickness of 6mm of the mold cleaning the rubber-based composition N.

Table 3 shows the characteristic values and the cleaning test results of the obtained rubber-based composition N for sheet mold cleaning. According to the test results, it was found that the rubber composition N for sheet mold cleaning exhibited good moldability and cleanability.

Industrial availability

As described above, the rubber-based composition for mold cleaning using an unvulcanized rubber is used, and the blending ratio of the unvulcanized rubber-based ethylene-propylene rubber to the butadiene rubber is set to 90/10 to 50/50 parts by weight, and The elongation after vulcanization hardening is 80-800%, the tensile strength is 3~10 MPa, the rubber hardness (hardness hardness) is shown as A60-95, 90% vulcanization time at 175 °C mold temperature (appropriate cure point) ) tc (90) is displayed as a value of 50 to 100 seconds or 200 to 400 seconds; thereby the workability (peelability) is good, and no debris or voids are generated, and the cavity or the runner or the gate can be easily removed. Dirt and easy removal of dirt from vents or mold sections.

In the rubber-based composition for cleaning a mold of the present invention, the third rubber composition for cleaning a mold of the present invention is preferably used for a mold for manufacturing a small-sized package such as PDIP or SOIC. Or the cleaning of a particularly small package manufacturing mold with a small number of pins in a small package.

Claims (8)

A rubber-based composition for cleaning a mold for removing dirt on a surface of a mold which is formed in a step of forming a curable resin, characterized in that the base resin is made of ethylene-propylene rubber and butadiene rubber. The blending ratio is set to 90/10 to 50/50 parts by weight of the unvulcanized rubber, and the elongation of the unvulcanized rubber after vulcanization and hardening is 80 to 800%, the tensile strength is 3 to 10 MPa, and the rubber hardness (hardness hardness) ) is A60~95, and the 90% vulcanization time (appropriate vulcanization point) tc (90) at a mold temperature of 175 ° C is in the range of 50 to 100 seconds; the butadiene rubber has a cis 1,4 bond A high cis structure having a content of 90% by weight or more. A rubber-based composition for cleaning a mold for removing dirt on a surface of a mold which is formed in a step of forming a curable resin, characterized in that the base resin is made of ethylene-propylene rubber and butadiene rubber. The blending ratio is set to 90/10 to 50/50 parts by weight of the unvulcanized rubber, and the elongation of the unvulcanized rubber after vulcanization and hardening is 80 to 800%, the tensile strength is 3 to 10 MPa, and the rubber hardness (hardness meter) Hardness) is A60~95, and 90% vulcanization time (appropriate vulcanization point) tc(90) at a mold temperature of 175 °C is in the range of 200 to 400 seconds; butadiene rubber has cis 1,4 bond The content is a high cis structure of 90% by weight or more. A rubber-based composition for cleaning a mold for removing dirt on a surface of a mold which is formed in a step of forming a curable resin, characterized in that the base resin is made of ethylene-propylene rubber and butadiene rubber. Tune The ratio is set to 90/10~50/50 parts by weight of unvulcanized rubber, and the unvulcanized rubber has an elongation ratio after vulcanization and hardening of 80 to 800%, a tensile strength of 3 to 10 MPa, and a rubber hardness (hardness hardness) a mold having a 90% vulcanization time (suitable vulcanization point) tc (90) at a mold temperature of 760 ° C and a value of 200 to 400 seconds, and the rubber composition for mold cleaning contains at least 1 A release agent; a butadiene rubber having a high cis structure having a cis 1,4 bond content of 90% by weight or more. The rubber-based composition for mold cleaning according to claim 3, wherein the ratio of the base resin to the release agent is from 3 to 15 parts by weight based on 100 parts by weight of the base resin. The rubber composition for mold cleaning according to any one of claims 1 to 4, wherein the blending ratio of the ethylene-propylene rubber to the butadiene rubber is set to 80/20 to 60/40 parts by weight. The rubber-based composition for mold cleaning according to any one of claims 1 to 4, which is of a compression type. The rubber composition for mold cleaning according to any one of claims 1 to 4, further comprising at least at least a filler, a cleaning agent, a cleaning aid, a vulcanizing agent, a vulcanization aid, a vulcanization accelerator, and a vulcanization accelerating aid 1 species. A mold cleaning method using the rubber-based composition for mold cleaning according to any one of claims 1 to 4.