TWI410316B - Mold cleaning and mold release resin for mold cleaning, mold cleaning and mold release recovery method - Google Patents

Abstract

A resin composition for cleaning molds and recovering the release properties of molds which can remove not only stains of a cavity, a runner and a gate but also stains of an air vent and a parting area of a mold and can impart release properties to the surface of a mold. The composition comprises a melamine resin, at least one metal soap type mold-releasing agent, and preferably mannitol and/or a mold-releasing agent other than metal soaps. The composition is a compression-type one which has both the ability to clean a mold and the ability to recover the release properties of a mold and thus dispenses with the release properties recovering step which was to be conducted after the completion of the mold cleaning step in the prior art.

Description

Resin composition for mold cleaning and mold release, mold cleaning and mold release recovery method

The present invention relates to a compression type mold cleaning and mold release recovery capable of removing dirt on a surface of a mold and providing mold release property on the surface of the mold, and having both cleanability and mold release property. A resin composition, and a mold cleaning and mold release recovery method using the resin composition.

When a sealing molded product such as an integrated circuit is formed by using a thermosetting resin such as an epoxy resin, if the molding time continues to be long, dirt may adhere to the inner surface of the mold, and if it continues to be formed in succession, it often results in The surface of the seal molded article has dirt adhering thereto, or the seal molded article adheres to the mold so that the forming operation cannot be continued. Therefore, since it is necessary to clean the mold regularly, it is proposed that the mold cleaning resin is molded at a plurality of injection ratios each time the molding material is subjected to shot molding for several times, and the mold is cleaned.

For example, in the case of forming a curable resin molding material (excluding an amine resin molding material), it is proposed to mold the surface of the mold by forming a material mainly composed of an amine resin. In the method, a resin composition for mold cleaning comprising an amine resin, an organic substrate, an inorganic substrate, and a release agent is disclosed.

In recent years, with the integration, thinning, and surface mounting of integrated circuits (abbreviated as IC (Integrated Circuit), LSI (Large Scale Integration)), molded products Shape, The diversification of the structure has been developed, and therefore, it is desired to achieve high fluidization of the semiconductor sealing material.

Therefore, when a highly fluidized epoxy sealing material is used, resin clogging tends to occur in the vent portion, and when such clogging occurs, air-bleeding becomes difficult, and the resin cannot flow, resulting in generation of resin. The cavity portion is unfilled and poorly formed, so that it is difficult to continuously form. Therefore, in order to avoid such a situation, it is necessary to perform cleaning. However, when the transfer type cleaning material is used, the resin does not flow normally due to the above reasons, and therefore it is difficult to remove the resin that is clogged in the vent hole.

On the other hand, after cleaning with the resin composition for mold cleaning, the surface of the mold can be cleaned, but conversely, there is also a problem that since the release agent on the surface of the mold is also removed, the mold is formed immediately after cleaning. The release property will become extremely poor. Therefore, after the resin composition for mold cleaning is used, it is necessary to mold the mold release-recovery resin composition to transfer the release agent in the mold release-recovery resin composition to the surface of the mold to restore the mold release property.

The mold is released from the resin composition, and the release agent is transferred to the surface of the mold to promptly recover the release property. Conventionally, as the mold release-recovery resin composition, for example, a component containing an epoxy resin, a phenol resin, a hardening accelerator, carnauba wax, and silica is used.

Similarly to the above, the mold release-recovery resin composition has a resin clogging in the vent hole portion, and the resin cannot flow into the entire vent hole, so that it is difficult to restore the vent hole portion.

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

As described above, the present invention solves the problem that resin clogging occurs in the vent hole portion due to high fluidization of the semiconductor sealing material, it is difficult to clean with the resin composition for mold cleaning due to clogging of the resin, and it is difficult to use the mold. The release resin composition is released to restore the mold release. Moreover, the present invention provides a resin composition for cleaning and mold release of a compression mold which has both cleanability and mold release recovery, which can easily perform cleaning or demolding recovery of a vent portion, and can be carried out in one step. The cleaning of the mold and the release of the mold are completed, and it is not necessary to clean the surface of the mold and then use the mold to release the resin composition to replenish the mold release component which is removed together with the dirt. Previous technical methods.

In order to solve the above problems, the present invention provides a resin composition for mold cleaning and mold release recovery, which is characterized in that it removes dirt on a mold surface and forms a mold when forming a curable resin molding material. The surface has a releasable resin composition and contains a melamine resin and contains at least one metal soap-based release agent.

The resin composition for mold cleaning and mold release recovery of the present invention preferably further contains a release agent other than mannitol or/metal soap.

The resin composition for mold cleaning and mold release recovery of the invention has the dual effects of the mold cleaning effect and the mold release recovery effect, and can not only remove the dirt of the cavity, the runner and the gate, but also Remove the vent portion And a contaminant material of a parting area of the mold, in particular, a compression type resin composition which can easily perform cleaning and release of the vent portion, which does not need to be carried out previously including the resin composition for cleaning with a mold The mold cleaning operation and the mold release recovery operation by the mold release recovery resin composition are performed in such a troublesome two-step operation, and the mold cleaning and mold release recovery can be completed in one step.

Hereinafter, the resin composition for mold cleaning and mold release recovery of the present invention will be described in detail.

The melamine resin used in the present invention can be produced by a known method.

For example, an initial aqueous solution of the condensate is prepared by reacting formaldehyde with melamine in a molar ratio of 1:1 to 4:1, preferably 1.5:1 to 3:1, in an aqueous solution. The reaction can be carried out under the conditions of melamine crystal concentration of 20-60%, reaction temperature of 70-100 ° C and weak alkalinity, and the reaction is completed after 10 to 100 minutes. One part of the above formaldehyde may be substituted by an aliphatic aldehyde such as acetal or an aldehyde component other than formaldehyde.

The resin composition for mold cleaning and mold release recovery of the present invention contains a metal soap-based release agent in addition to the melamine resin.

Examples of the metal soap-based release agent include calcium stearate, zinc stearate, and zinc myristate. The amount of the metal soap-based release agent added is preferably 0.2 to 1.0 part by weight, more preferably 0.4 to 0.8 part by weight, per 100 parts by weight of the melamine resin. If the amount of the metal soap-based release agent is insufficient, the mold release property and cleanability are lowered, and if the metal soap system is When the amount of the release agent added is too large, the mold release property is good, but the cleanability is lowered.

The resin composition for mold cleaning and mold release recovery of the present invention preferably further contains mannitol in addition to the melamine resin and the metal soap release agent. By containing mannitol, it is possible to maintain the mold release property while reducing the heating fading.

As the mannitol, D-mannitol is preferred.

When mannitol is contained, it is preferred that the ratio of the metal soap-based release agent to the mannitol is from 90:10 to 30:70 by weight, particularly preferably from 80:20 to 40:60. If the proportion of mannitol is too large, the cleanability will be poor.

The amount of mannitol added is preferably 0.2 to 1.0 part by weight, more preferably 0.3 to 0.8 part by weight, per 100 parts by weight of the melamine resin. When the amount of mannitol added is insufficient, there is no additive effect, and if the amount of mannitol added is too large, the mold release property is good, but the cleanability is lowered.

Further, the resin composition for mold cleaning and mold release of the present invention is preferably a mold release agent other than the metal soap, in addition to the melamine resin and the metal soap release agent. By containing a mold release agent other than the metal soap, mold release property can be exhibited without being affected by the mold release component in the epoxy sealing material.

Examples of the release agent other than the metal soap include an ester-based release agent such as a montanic acid partially saponified ester or a polymer complex ester, and a synthetic wax such as a modified hydrocarbon wax or a mineral oil-based synthetic wax. Specifically, Licowax OP (partial saponification of montanic acid produced by Clariant Japan Co., Ltd.) can be suitably used. Ester), Loxiol G78 (polymer complex ester made by Cognis Japan Co., Ltd.), Licolub H-4 (modified hydrocarbon manufactured by Clariant Co., Ltd., Japan), and Loxiol VPN881 (manufactured by Nippon Corning Co., Ltd.) Commercial products such as mineral oil synthetic wax). The release agent other than the metal soap is preferably an ester-based release agent and a synthetic wax as exemplified above. When a release agent other than those listed herein is used, the cleanability may be deteriorated.

When a mold release agent other than the metal soap is contained, it is preferred that the ratio of the metal soap release agent to the mold release agent other than the metal soap is 90:10 to 30:70 by weight, particularly preferably It is 80:20~40:60. If the proportion of the release agent other than the metal soap is too large, the cleanability may be deteriorated.

The amount of the release agent other than the metal soap is preferably 0.02 to 0.7 parts by weight, more preferably 0.1 to 0.5 part by weight, per 100 parts by weight of the melamine resin. When the amount of the release agent other than the metal soap is insufficient, there is no additive effect, and if the amount of the release agent other than the metal soap is too large, the mold release property is good, but the cleanability is lowered.

In the resin composition for mold cleaning and mold release recovery of the present invention, in order to improve the cleaning effect, it is preferred to contain pulp. As the pulp, grass pulp, bamboo pulp, wood pulp (conifer pulp, hardwood pulp), or the like, or any of chemical pulp and mechanical pulp can be used.

Preferably, the melamine resin which is an essential component of the resin composition for mold cleaning and mold release recovery of the present invention is immersed in the form of the pulp (resin impregnated pulp), and the pulp is present in the present invention. The resin composition for mold cleaning and mold release recovery. The resin impregnated pulp can be obtained by immersing the pulp in a melamine-formaldehyde resin aqueous solution. Prepared by drying. Further, part or all of the above pulp may be replaced with powdered pulp, whereby the fluidity can be further improved.

The size of the above pulp is not particularly limited, but is usually from 5 to 1,000 μm, preferably from about 10 to 200 μm. Further, the content of the above pulp is usually 5 to 70 parts by weight, preferably 20 to 60 parts by weight, per 100 parts by weight of the melamine resin. If the content of the pulp is less than 5 parts by weight, there is no additive effect; if it exceeds 70 parts by weight, the fluidity is deteriorated, and it is not possible to fill the respective corners of the mold, so that dirt remains on the mold, which is not preferable.

It is preferable that the resin composition for mold cleaning and mold release recovery of the present invention further contains a curing catalyst. Examples of the curing catalyst include organic acids such as phthalic anhydride, oxalic acid, sulfamic acid, and p-toluenesulfonic acid, and inorganic acids such as hydrochloric acid and sulfuric acid, such as triethylamine, triethanolamine, and β-dimethylamine ethanol. a salt such as 2-methyl-2-amino-1-propanol. The amount of the curing catalyst to be added is usually 1.5 parts by weight or less and 0.05 part by weight or more, preferably 1 part by weight or less and 0.1 part by weight or more based on 100 parts by weight of the melamine resin.

It is preferable that the resin composition for mold cleaning and mold release of the present invention contains at least one selected from the group consisting of the above-mentioned pulp and a curing catalyst.

Further, in the resin composition for mold cleaning and mold release recovery of the present invention, a coloring agent such as a pigment, a fibrous filler other than pulp, a filler having a low hardness and a small particle diameter, and the like can be appropriately added.

When preparing the resin composition for mold cleaning and mold release recovery of the present invention, it is possible to use a melamine resin, a metal soap release agent, a release agent other than mannitol or metal soap, and other additives such as pulp. mixing And any method of making it.

For example, a kneader, a belt type mixer, a Henschel mixer, a ball mill, a drum mixer, a stone mill, a roller machine, etc. are mentioned.

The curable resin molding material which can be used for cleaning and releasing the mold for the mold cleaning and the mold release-recovering resin composition of the present invention is, for example, an epoxy resin molding material or a phenol resin molding material. Preferably, it is an epoxy resin molding material, and particularly preferably an epoxy resin molding material for semiconductor packaging. Further, the resin composition for mold cleaning and mold release of the present invention can be used in any mold used for automatic molding of the curable resin molding material, but it is usually used for a mold composed of iron, chromium or the like. The effect is better.

The mold for cleaning the mold and the mold release for mold release of the present invention are molded by a mold, whereby the dirt on the surface of the mold can be removed and the surface of the mold can be released. The molding conditions of the resin composition for mold cleaning and mold release recovery of the present invention are preferably a mold temperature of 160 to 190 ° C, a molding pressure of 10 to 20 MPa, and a curing time of 2 to 3 minutes.

Example

Hereinafter, the present invention will be described in detail by way of examples and the like, but the invention is not limited by the examples and the like.

(Manufacturing Example 1)

Using a well-known method, 480 parts by weight of melamine and 520 parts by weight of formalin (37% aqueous solution) and 350 parts by weight of water are subjected to a heat reaction to prepare a melamine-formaldehyde resin, and 257 weights are added to the obtained aqueous melamine resin solution. The pulp is mixed and then reduced The mixture was dried by pressure to obtain a melamine-formaldehyde resin powder (melamine resin impregnated pulp) mixed with pulp having a resin content of about 72%.

(Manufacturing Example 2)

The aqueous melamine resin solution (solid content: about 60% by weight) obtained in Production Example 1 was dried by a spray dryer at a temperature of about 200 ° C, whereby a powdery melamine resin was obtained.

[Example 1]

Using a ball mill, 1000 parts by weight of a melamine-formaldehyde resin powder mixed with pulp having a resin content of about 72%, 0.5 parts by weight of phthalic anhydride, and 6.0 parts by weight of zinc stearate were used. By mixing, the resin composition A for mold cleaning and mold release recovery was obtained. The mold cleanability and mold release property of the obtained resin composition A were evaluated by the following test methods. The results are shown in Table 1. As shown in Table 1, the resin composition A exhibited excellent mold cleanability. Further, when the epoxy resin sealing material is formed without using the resin composition for mold release recovery after the mold cleaning by the resin composition A, the mold release property exhibited at this time is not inferior to that of the previous mold. The mold release property when the resin composition for mold release is released.

[Embodiment 2]

Using a ball mill, 1000 parts by weight of a melamine-formaldehyde resin powder mixed with pulp having a resin content of about 72% obtained in Production Example 1, 30 parts by weight of a powdery melamine resin obtained in Production Example 2, and 30 parts by weight a portion of the powdered pulp, 0.5 parts by weight of phthalic anhydride, 2.5 parts by weight of zinc stearate, and 3.5 parts by weight of calcium stearate, Resin composition B for mold cleaning and mold release. The mold cleanability and mold release property of the obtained resin composition B were evaluated in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, the resin composition B exerted excellent mold cleanability. Further, when the epoxy resin sealing material is formed without using the resin composition for mold release recovery after the mold cleaning by the resin composition B, the mold release property exhibited at this time is not inferior to that of the previous mold. The mold release property when the resin composition for mold release is released.

[testing method]

For the cleanability test, a commercially available biphenyl-based epoxy resin molding material (EME-7351T manufactured by Sumitomo Bakelite Co., Ltd.) was used, and a mold of TQFP (Thin Quad Flat Pack) was used. 500 shots were formed to form a dirt of the mold. The evaluation was carried out by using the mold to which the existing dirt adhered, and repeatedly molding the resin composition for mold cleaning and mold release, until the surface of the mold was cleaned.

Reply release end of the test after the cleaning test, the commercially available biphenyl-based epoxy resin molding material (manufactured by Sumitomo Bakelite Co., EME-7351T) continuous molding test, whereby the mold releasability confirmed. Further, the mold composition for mold cleaning and mold release recovery which was inferior in mold cleanability and which was not cleaned was not subjected to the mold release recovery test.

[Example 3]

Using a ball mill, 1000 parts by weight of the melamine-formaldehyde resin powder mixed with pulp having a resin content of about 72%, 0.5 parts by weight of phthalic anhydride, and 3.0 parts by weight of zinc stearate obtained in Production Example 1 were used. And 2.0 parts by weight of D-mannitol were mixed, whereby a resin composition C for mold cleaning and mold release recovery was obtained. The mold cleanability and mold release property of the obtained resin composition C were evaluated in the same manner as in Example 1. The results are disclosed in Table 2. As shown in Table 2, the resin composition C exhibited excellent mold cleanability. Further, when the epoxy resin sealing material is molded without using the resin composition for mold release recovery after the mold cleaning by the resin composition C, the mold release property exhibited at this time is not inferior to that of the previous mold. The mold release property when the resin composition for mold release is released.

[Example 4]

Using a ball mill, 1000 parts by weight of a melamine-formaldehyde resin powder mixed with pulp having a resin content of about 72%, 0.5 part by weight of phthalic anhydride, and 1.5 parts by weight of zinc stearate obtained in Production Example 1 were used. And 3.0 parts by weight of D-mannitol were mixed, whereby a resin composition D for mold cleaning and mold release recovery was obtained. The mold cleanability and mold release property of the obtained resin composition D were evaluated in the same manner as in Example 1. its The results are disclosed in Table 2. As shown in Table 2, the resin composition D exhibited excellent mold cleanability. Further, when the epoxy resin sealing material is molded without using the resin composition for mold release recovery after the mold cleaning by the resin composition D, the mold release property exhibited at this time is not inferior to that of the previous mold. The mold release property when the resin composition for mold release is released.

[Example 5]

Using a ball mill, 1000 parts by weight of a melamine-formaldehyde resin powder mixed with pulp having a resin content of about 72%, 0.5 parts by weight of phthalic anhydride, and 2.5 parts by weight of zinc stearate obtained in Production Example 1 were used. And 3.5 parts by weight of Licowax OP (a partially saponified ester of montanic acid manufactured by Clariant Co., Ltd., Japan) was mixed, whereby a resin composition E for mold cleaning and mold release recovery was obtained. The mold cleanability and mold release property of the obtained resin composition E were evaluated in the same manner as in Example 1. The results are disclosed in Table 3. As shown in Table 3, the resin composition E exhibited excellent mold cleanability. Further, when the epoxy resin sealing material is molded without using the resin composition for mold release recovery after the mold cleaning by the resin composition E, the mold release property exhibited at this time is not inferior to that of the previous mold. The mold release property when the resin composition for mold release is released.

[Embodiment 6]

Using a ball mill, 1000 parts by weight of a melamine-formaldehyde resin powder mixed with pulp having a resin content of about 72%, 0.5 parts by weight of phthalic anhydride, and 2.5 parts by weight of zinc stearate obtained in Production Example 1 were used. The resin composition F for mold cleaning and mold release recovery was obtained by mixing 1.0 parts by weight of Loxiol G78 (polymer complex ester manufactured by Nippon Corning Co., Ltd.). The mold cleanability and mold release property of the obtained resin composition F were evaluated in the same manner as in Example 1. The results are disclosed in Table 3. As shown in Table 3, the resin composition F exhibited excellent mold cleanability. Further, when the epoxy resin sealing material is formed without using the resin composition for mold release recovery after the mold cleaning by the resin composition F, the mold release property exhibited at this time is not inferior to that of the previous mold. The mold release property when the resin composition for mold release is released.

[Embodiment 7]

Using a ball mill, 1000 parts by weight of a melamine-formaldehyde resin powder mixed with pulp having a resin content of about 72% obtained in Production Example 1, 30 parts by weight of a powdery melamine resin obtained in Production Example 2, and 30 parts by weight a portion of the powdered pulp, 0.5 parts by weight of phthalic anhydride, 2.5 parts by weight of zinc stearate, and 3.5 parts by weight of Licolub H-4 (modified hydrocarbon manufactured by Clariant Co., Ltd., Japan) are mixed. Resin composition G for mold cleaning and mold release. The mold cleanability and mold release property of the obtained resin composition G were evaluated in the same manner as in Example 1. The results are disclosed in Table 3. As shown in Table 3, the resin composition G exhibited excellent mold cleanability. Moreover, after the mold cleaning by the resin composition G, the epoxy resin sealing material is used without using the mold release-recovering resin composition. When the material is formed, the mold release property exhibited at this time is not inferior to that of the previous mold release resin composition for mold release recovery.

[Embodiment 8]

Using a ball mill, 1000 parts by weight of a melamine-formaldehyde resin powder mixed with pulp having a resin content of about 72% obtained in Production Example 1, 30 parts by weight of a powdery melamine resin obtained in Production Example 2, and 30 parts by weight a portion of the powdered pulp, 0.5 parts by weight of phthalic anhydride, 2.5 parts by weight of zinc stearate, and 3.0 parts by weight of Loxol VPN 881 (mineral oil-based synthetic wax made by Nippon Corning Co., Ltd.) are mixed. Resin composition H for mold cleaning and mold release. The mold cleanability and mold release property of the obtained resin composition H were evaluated in the same manner as in Example 1. The results are disclosed in Table 3. As shown in Table 3, the resin composition H exhibited excellent mold cleanability. Moreover, when the epoxy sealing material is formed without using the resin composition for mold release recovery after the mold cleaning by the resin composition H, the mold release property exhibited at this time is not inferior to that of the previous mold. The mold release property when the resin composition for mold release is released.

Industrial availability

Resin group for mold cleaning and mold release recovery by using the present invention The compound can remove the obvious dirt at the cavity portion, the vent hole portion and the like due to the high functionalization of the epoxy sealing resin and the high functionalization of the semiconductor element in recent years, and it is not necessary to clean the mold as before. After the end, the mold release operation must be carried out to make the mold release. Therefore, it is possible to reduce the troublesome operation of one of the series of mold cleaning operations and the mold release recovery operation, thereby shortening the operation time. Moreover, it is not necessary to use a member such as a lead frame or a dummy frame necessary for transfer molding, and thus it is also possible to reduce the costs associated with a series of mold cleaning operations and mold release recovery operations.

Claims (4)

A resin composition for mold cleaning and mold release recovery, which is characterized in that, when forming a curable resin molding material, dirt on a surface of a mold is removed and mold surface is released, and the resin composition contains A melamine resin and containing at least one metal soap-based release agent, further containing mannitol. The resin composition for mold cleaning and mold release recovery according to claim 1, wherein the mannitol is D-mannitol. The resin composition for mold cleaning and mold release recovery according to claim 1 or 2, wherein the content ratio of the metal soap-based release agent to the mannitol is 90:10 to 30:70 by weight. A mold cleaning and mold release recovery method using the resin composition for mold cleaning and mold release recovery according to any one of claims 1 to 3.