JPH08283454A - Composition for cleaning metallic mold - Google Patents

Abstract

PURPOSE: To obtain the subject composition, containing a high polymer material as a principal component and further a specific compound containing nitrogen therein, capable of sticking and integrating foulings on the surface of a metallic mold and effectively removing the foulings from the metallic mold and especially useful for cleaning the metallic mold for molding a biphenyl-based epoxy resin. CONSTITUTION: This composition contains (A) a high polymer material such as an ethylene-propylene rubber or its mixture with a butadiene rubber as a principal component and further (B) 1,8-diazabicyclo[5.4.0]undecene-7 of formula I or its salt or (C) 1,5-diazabicyclo[4.3.0]nonene-5 of formula II or its salt therein. Furthermore, the component (B) or (C) is preferably contained in an amount of preferably 2-18 pts.wt., especially preferably 5-15 pts.wt. based on 100 pts.wt. component (A).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for cleaning a mold such as a mold for a thermosetting resin molding material, which has been contaminated by repeating molding operations of a resin composition for semiconductor molding. It relates to a composition.

[0002]

2. Description of the Related Art At the time of molding a thermosetting resin molding material using a molding die, a mold release agent contained in the thermosetting resin molding material exudes to the surface of the mold and exhibits a mold releasing action. To do.
If such a molding process is repeated, the mold releasability of the molded product is deteriorated and the appearance is deteriorated. The reason for this is that the release agent contained in the above-mentioned molding material exudes to the surface of the mold and gradually deteriorates while being successively laminated on the surface of the mold by repeating the molding process, and the effect as the release agent is lost. It is thought that this is because a pollutant layer is formed. In order to solve such a problem, the work of cleaning the mold is performed when a contaminant layer, which is a deteriorated layer of the release agent, is formed. For example, conventionally, a thermosetting melamine resin molding material was placed in the mold and molded and cured, and contaminants on the mold surface were integrated with the molded product, and a molded product in which the contaminants were integrated was prepared. It is practiced to clean the surface of the mold by removing it from the mold. However, in such a cleaning method, formalin is produced as a by-product as a condensate of the thermosetting melamine resin molding material and an odor is generated, and since it is difficult to remove this molding product and it takes a long time, the working environment is significantly high. This deteriorates the cleaning workability.

Therefore, recently, when an unvulcanized rubber compound is used in place of the thermosetting melamine resin molding material, the compound is vulcanized in a mold to form a vulcanized rubber, which is then converted into a vulcanized rubber. In addition, the contaminants on the mold surface are integrated with the vulcanized rubber,
Then, a method of cleaning the surface of the mold by removing the vulcanized rubber from the mold has been proposed and partially implemented.

[0004]

However, the above-mentioned thermosetting resin molding materials differ in composition depending on the required properties, and there are many types, and the state of mold contamination and the components of contaminants which occur due to repeated molding. It is used for various purposes. Among them, the mold contaminants when molding is repeated using a molding material containing a biphenyl epoxy resin as the main component, the baking on the mold surface is bad, so use the above unvulcanized rubber compound. However, there is a problem that it cannot be completely removed by such a conventional cleaning method.

The present invention has been made in view of such circumstances, and an object thereof is to provide a mold cleaning composition having an excellent cleaning effect on a semiconductor molding mold.

[0006]

In order to achieve the above object, the mold cleaning composition of the present invention comprises a polymer material as a main component and at least one of the following components (A) and (B). Is included. (A) 1,8-diazabicyclo (5,4,0) undecene-7 and / or a salt thereof. (B) 1,5-diazabicyclo (4,3,0) nonene-
5 and / or at least one of its salts.

[0007]

That is, the present inventors have made a series of cleaning products for effectively removing contaminants on the mold surface formed by repeating molding using a molding material containing a biphenyl epoxy resin as a main component. Repeated research. As a result, as a cleaning agent, 1,8-diazabicyclo (5,4,4)
0) Undecene-7 (hereinafter referred to as “DBU”) and at least one of salts thereof [(A) component], 1,5-diazabicyclo (4,3,0) nonene-5 (hereinafter referred to as “DBN”) and salts thereof. When the mold surface is cleaned using a mold cleaning composition containing a specific substance of at least one of the above (Component (B)), contaminants on the mold surface form the mold cleaning composition. They have reached the present invention by finding that they can be integrated with a product and that contaminants can be effectively removed from the mold. In particular, when a rubber material such as ethylene-propylene rubber or a mixture of ethylene-propylene rubber and butadiene rubber is used as the base polymer material containing the above-mentioned detergent, a bad odor generated during heating is reduced and a work environment is improved. Therefore, it has been found that it is particularly preferable because the effect of becoming advantageous is obtained.

Next, the present invention will be described in detail.

The mold cleaning composition of the present invention can be obtained by using a base polymer material and a specific cleaning agent.

As the polymer material, various rubber materials,
Resin materials and the like can be mentioned. The above-mentioned rubber material is not particularly limited, but among them, ethylene-propylene rubber (hereinafter referred to as “EPR”) is preferable from the viewpoint of working environment.
) Or a mixture of this EPR and butadiene rubber (hereinafter referred to as “BR”) is preferably used. The mixing ratio (x / y) of EPR (x) and BR (y) in the mixture of EPR and BR is x /
It is preferable to set y in the range of 100/0 to 20/80. In particular, when both EPR and BR are used in combination, the preferable mixing ratio is in the range of x / y = 30/70 to 40/60. That is, in the mixture ratio of both, EP
If R is less than 20 (EPR is more than 80), the strength of the molded product is lowered when removing the rubber molded product during the molding work, and problems such as tearing occur and removal work from the mold becomes difficult. This is because there is a tendency. The above E
For PR, ethylene-propylene-diene rubber (EPD
It is also meant to include M).

The specific detergent contained in the polymer material includes at least one of DBU and its salt (component A), at least one of DBN and its salt (component B), and the above-mentioned components A and B. A mixture is used.

DBU as the above-mentioned component A and DBU in the salt thereof are superbasic substances represented by the following chemical formula (1).

[0013]

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The DBU salt is represented by the following general formula (2).

[0015]

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In the above general formula (2), X represents an inorganic acid residue or an organic acid residue, and typical examples of the DBU salt are DBU formate, DBU orthophthalate and DU.
Organic acid salts of DBU such as octyl acid salt of BU, phenol salt of DBU, and p-toluenesulfonic acid salt of DBU can be used. The content of at least one of the DBU and its salt (component A) is preferably set to 2 to 18 parts with respect to 100 parts by weight of the polymer material (hereinafter abbreviated as “part”), and particularly preferably. 5 to 15 parts. That is, if the content of the A component is too small, such as less than 2 parts, the detergency of the mold decreases, and conversely, if it exceeds 18 parts, the A component excessively exudes to the mold surface and the mold surface is contaminated. This is because there is a tendency to cause

Further, DBN as the B component and DBN in the salt thereof are represented by the following chemical formula (3).

[0018]

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The above DBN salt is represented by the following general formula (4).

[0020]

[Chemical 4]

In the above general formula (4), X represents an inorganic acid residue or an organic acid residue, and typical examples of the DBN salt include DBN formate, DBN orthophthalate, and DN.
Examples thereof include organic acid salts of DBN such as octyl acid salt of BN, phenol salt of DBN, p-toluenesulfonic acid salt of DBN. And, the content of at least one of the DBN and its salt (component B) is the same as in the case of the component A.
It is preferably set to 2 to 18 parts, and particularly preferably 5 to 15 parts, relative to 100 parts of the polymer material. That is, if the content of the B component is too small, such as less than 2 parts, the detergency of the mold decreases, and conversely, if it exceeds 18 parts, the B component excessively exudes on the mold surface and the mold surface is contaminated. This is because there is a tendency to cause

In addition to the above-mentioned components, the mold cleaning composition of the present invention may optionally contain a reinforcing agent such as silica powder,
Vulcanizing agents such as organic peroxides, vulcanizing aids such as imidazole,
Other additives such as pigments can be appropriately mixed.

The blending amount of the above-mentioned other additives is the polymer material 1
With respect to 00 parts, it is preferable to set 40 to 50 parts for the reinforcing agent, 1 to 3 parts for the vulcanizing agent, and 5 to 15 parts for the vulcanization aid.

A particularly preferable combination of the respective components which are the raw materials of the mold cleaning composition of the present invention is a combination of EPR and BR as the polymer materials from the viewpoint of improving the cleaning property.
Is a combination of a DBU formate or a DBN formate as a cleaning agent, and a reinforcing agent, a vulcanizing agent and a vulcanization aid are added thereto.

The mold cleaning composition of the present invention is obtained as follows. That is, a base polymer material and at least one of DBU and its salt (component A),
It can be obtained by mixing at least one of DBN and its salt (component B) alone or both, and further mixing these with other additives and kneading them with a kneader. The mold-cleaning composition thus obtained is used, for example, by forming the mold-cleaning composition into a sheet using a rolling roll or the like. When used as this sheet-shaped molding material, the thickness of the sheet is set to 3 to 10 mm.

Then, the mold is cleaned by loading the mold cleaning composition formed into a sheet into the mold. For example, when the base polymer material is a rubber material, the above-mentioned sheet is in an unvulcanized state, and the sheet is loaded into a mold and vulcanized by heating so that contaminants are attached to and integrated with the sheet. Next, the vulcanized sheet is taken out of the mold to clean the mold.

The cleaning of the mold is considered to be performed by the following mechanism. That is, at the time of heat vulcanization, the components A and B, which are the cleaning agents in the rubber composition, exude to the mold surface and swell contaminants adhering to the mold surface. This facilitates peeling and removal of contaminants from the mold surface. Then, the contaminants peeled from the surface of the mold are adhered to and integrated with the vulcanized sheet, and the sheet is taken out from the mold, whereby the contaminants on the surface of the mold are removed and the mold is washed.

Next, since the mold cleaned with the mold cleaning composition of the present invention is free of contaminants and returns to the initial mold surface, it is usually a thermosetting resin molding material. When molding, a mold release agent must be applied to the surface of the mold in advance. For example, when molding a molding material containing polyethylene wax as a mold release agent, the same polyethylene wax may be applied. preferable. And
As a method of applying the polyethylene wax to the surface of the mold, it is preferable to use an unvulcanized rubber composition containing polyethylene wax prepared and formed into a sheet. Then, the sheet made of the unvulcanized rubber composition containing the polyethylene wax is loaded into the mold and heated as in the above-mentioned cleaning step, so that the contained polyethylene wax is applied to the surface of the mold. It is considered that this is because the polyethylene wax in the unvulcanized rubber composition melts during heat vulcanization and exudes to the mold surface to form a uniform release agent film on the surface. The content of the polyethylene wax is preferably set to 15 to 35 parts, and particularly preferably 20 to 30 parts, based on 100 parts of the rubber material in the unvulcanized rubber composition. That is, when the content of polyethylene wax is less than 15 parts, a sufficient releasing effect is not exerted, and when it exceeds 35 parts, it is excessively applied to the surface of the mold and molding is performed using the mold after washing and regeneration. This is because when a product is formed, the appearance of the molded product tends to deteriorate.

Next, examples will be described together with comparative examples.

An example in which at least one of DBU and its salt (component A) is used as a cleaning agent will be described.

[0031]

Examples 1 to 10 The components shown in Tables 1 and 2 below were mixed in the proportions shown in the same table and kneaded with a kneader. Then, this was molded into a sheet having a thickness of 5 mm by using a rolling roll to obtain a target mold cleaning composition.

[0032]

[Table 1]

[0033]

[Table 2]

An example in which at least one of DBN and its salt (component B) is used as a detergent will be described.

[0035]

[Examples 11 to 22] The components shown in Tables 3 to 4 below were mixed in the proportions shown in the same table and kneaded by a kneader. Then,
This was molded into a sheet having a thickness of 5 mm using a rolling roll to obtain a target mold cleaning composition.

[0036]

[Table 3]

[0037]

[Table 4]

A comparative example will be described.

[0039]

[Comparative Examples 1 and 2] The components shown in Table 5 below were mixed in the proportions shown in the same table and kneaded with a kneader. Then, this was molded into a sheet having a thickness of 5 mm by using a rolling roll to obtain a target mold cleaning composition.

[0040]

[Table 5]

The surface of the sheet-shaped mold cleaning composition of the example product and the comparative product thus obtained was contaminated by repeated molding of the molding resin composition using the biphenyl epoxy resin. Sandwiched between the molded molds,
After heat vulcanization at 5 ° C. for 5 minutes, it was taken out from the mold and the removability of contaminants was visually confirmed and evaluated. Further, the thermosetting melamine resin (Comparative Example 2) was molded by transfer molding.
After heat curing at 5 ° C. for 3 minutes, it was taken out from the mold, and the removability of contaminants was visually confirmed and evaluated in the same manner. And
In the evaluation, those in which the contaminants were completely removed were evaluated as good, and those in which the contaminants were not completely removed were evaluated as bad. The results are shown in Tables 6 to 7 below.

[0042]

[Table 6]

[0043]

[Table 7]

From the results shown in Tables 6 to 7 above, the comparative example product had a poor mold cleaning property, and the contaminants were not sufficiently removed. On the other hand, in all the example products, it was confirmed that the contaminants formed on the surface of the mold were transferred and adhered to the surface of the sheet-shaped mold cleaning composition taken out from the mold, It was also confirmed that the surface of the mold was washed sufficiently.

Further, a sheet-like mold release recovery composition (based on a mixture of BR and EPR) containing polyethylene wax was sandwiched between the molds cleaned by the above-mentioned example product and comparative example product, and heated. Sulfurization (175 ° C. × 3 minutes) was performed and the mold release agent was applied to the mold surface. Then, transfer molding was normally carried out using a molding resin composition containing a polyethylene wax prepared by using a biphenyl epoxy resin in a mold coated with a release agent. Then, the appearance of the obtained molded product was visually evaluated. In the evaluation, the obtained molded articles having good appearance were evaluated as good, and those having poor appearance (having surface unevenness) were evaluated as poor. The results are shown in Tables 8 to 9 below.

[0046]

[Table 8]

[0047]

[Table 9]

From the results shown in Tables 8 to 9 above, the appearance of all the molded articles obtained by the die in which the surface of the die was sufficiently cleaned using the example articles was good.

[0049]

INDUSTRIAL APPLICABILITY As described above, the mold cleaning composition of the present invention uses, as a cleaning agent, at least one of DBU and its salt (component A) and at least one of DBN and its salt (component B). One or both are contained. Therefore, when the mold surface is cleaned using the mold cleaning composition of the present invention, contaminants on the mold surface adhere to and are integrated with the mold cleaning composition, resulting in contamination from the mold. Effectively removed. Therefore, the molded product formed by using the mold cleaned with the mold cleaning composition of the present invention can have excellent appearance. In particular, the mold cleaning composition of the present invention is useful for cleaning a mold that is molded using a molding material containing a biphenyl epoxy resin as a main component, which is widely used in recent years as a semiconductor sealing material.

Claims (3)

[Claims] 1. A polymer material as a main component, comprising the following (A):
A mold cleaning composition comprising at least one of a component and a component (B). (A) 1,8-diazabicyclo (5,4,0) undecene-7 and / or a salt thereof. (B) 1,5-diazabicyclo (4,3,0) nonene-
5 and / or at least one of its salts. 2. The polymer material is a rubber material.
The mold cleaning composition as described above. 3. The mold cleaning composition according to claim 2, wherein the rubber material is ethylene-propylene rubber or a mixture of ethylene-propylene rubber and butadiene rubber.