JP5991997B2 - Mold cleaning resin composition - Google Patents

Description

  The present invention relates to a mold cleaning resin composition. More specifically, the present invention relates to a transfer-type mold cleaning resin composition that removes dirt on the inner surface of a molding die derived from a thermosetting resin composition.

  In the case of sealing molding using a sealing molding material containing a thermosetting resin composition, if sealing molding operations such as integrated circuits and LED elements are continued for a long period of time, stains derived from the sealing molding material are likely to occur. . Due to the occurrence of such dirt, there is a problem that the inside of the molding die becomes dirty. If such dirt is left in the mold, a problem occurs in which dirt adheres to the surface of a molded product such as an integrated circuit or an LED element. Therefore, when sealing molding is performed, it is required to remove dirt in the molding die. Specifically, in the case of sealing molding, it is desirable to mold the mold cleaning resin composition instead of the sealing molding material at a rate of several shots every time hundreds of shots are sealed. By molding the mold cleaning resin composition, it is possible to remove stains on the inner surface of the molding die.

  Such a mold cleaning resin composition has been conventionally proposed. For example, the resin composition for mold cleaning described in Patent Document 1 contains 10 to 70% by mass of an epoxy-modified melamine resin based on the total amount of the amino resin, and is obtained by molding at the time of mold cleaning. The hot toughness of the molded product is improved and the workability of mold cleaning is improved.

  In recent years, the shape and structure of sealing molding of integrated circuits, LED elements, and the like have been diversified and refined in order to cope with the high performance of devices used. Therefore, diversification and refinement are also required for the shape and structure of the molding die used in the sealing molding process. Such cleaning of the molding die is required to remove the dirt to every corner of the mold cavity including the corner portion where the dirt tends to remain.

  Patent Document 1 discloses a resin composition for mold cleaning in which a mineral powder having a maximum particle size of 180 μm or less and a particle size of 100 μm or more is 1% by mass with respect to the total amount of mineral powder. Things are listed. The resin composition for mold cleaning described in Patent Document 1 has an effect of improving the cleaning workability due to clogging in a narrow gate portion, because the resin composition for mold cleaning spreads every corner inside the gap. Yes. However, the effect is not sufficient and there is room for improvement. Furthermore, the mold cleaning resin composition described in Patent Document 1 has room for improvement in the removal performance of dirt in the mold.

  When the mold is cleaned, if a mold cleaning resin composition having a small filler is used, clogging of a narrow gate portion of the densified mold cavity can be suppressed. However, when the size of the filler is reduced, the physical polishing effect of the filler is reduced, and in particular, there is a problem in that the performance of removing dirt at the corner portion is lowered. Moreover, the mold cleaning resin composition in which the filler is reduced in size causes an excessive flow of the mold cleaning resin composition during cleaning. Therefore, there is a problem that the dirt cannot be sufficiently removed because the mold cleaning resin composition does not properly remain in the mold.

JP 2003-62835 A

  The present invention has been made in view of the above situation. That is, under the above circumstances, there is a need for a mold cleaning resin composition that can provide a good cleaning effect, for example, to a corner portion of a fine mold cavity, and has improved dirt removal performance. Yes.

The mold cleaning resin composition of the present invention is a mold cleaning resin composition containing a melamine-based resin, an inorganic filler, a curing catalyst, a salt of a saturated fatty acid and a metal,
The inorganic filler is spherical,
The maximum particle size of the inorganic filler is in the range of 1 μm to 70 μm,
The curing catalyst is at least one selected from myristic acid and stearic acid,
The salt of the saturated fatty acid and the metal is zinc myristate.

Further, the mold cleaning resin composition of the present invention, the inorganic filler, the standard deviation of the particle size is not more 7μm or less, and an average aspect ratio of grain size in the 1 to 1.2, aspect ratio standard An embodiment in which the deviation is 0.3 or less is preferable.

  Further, the mold cleaning resin composition of the present invention is preferably a transfer type mold cleaning resin composition used in a transfer molding machine. That is, the mold cleaning resin composition of the present invention is suitably used for transfer molding.

  According to the present invention, the shape of the inorganic filler is specified, and the range of the particle diameter is specified, and the corner of the fine mold cavity is obtained by using a specific curing catalyst, a specific saturated fatty acid, and a metal salt. A mold cleaning resin composition having a good cleaning effect up to the portion and improved dirt removal performance is provided.

Hereinafter, embodiments of the resin composition for mold cleaning of the present invention will be described.
The resin composition for mold cleaning of the present invention comprises at least a melamine resin, a spherical inorganic filler having a maximum particle size of 1 μm to 70 μm, a curing catalyst selected from myristic acid and stearic acid, a saturated fatty acid, And zinc myristate which is a salt with metal. The resin composition for mold cleaning of the present invention may be configured using other components as necessary.

-Melamine resin-
The mold cleaning resin composition of the present invention contains at least one melamine-based resin.
The melamine resin refers to a melamine resin, a melamine-phenol cocondensate, or a melamine-urea cocondensate.

  The melamine resin is a condensate of triazines and aldehydes. Examples of triazines include melamine, benzoguanamine, and acetoguanamine. Examples of aldehydes include formaldehyde, paraformaldehyde, and acetaldehyde.

  The melamine-phenol cocondensate is a cocondensate of triazines, phenols and aldehydes. Examples of phenols include phenol, cresol, xylenol, ethylphenol, and butylphenol.

  The melamine-urea cocondensate is a cocondensate of triazines, ureas, and aldehydes.

  The resin composition for mold cleaning of the present invention is not limited to the melamine resin, and other resin compositions, for example, alkyd resins, polyester resins, acrylic resins, epoxy resins, and rubbers, as long as the effects of the present invention are not impaired. Can be included.

  Since the resin composition for mold cleaning of the present invention contains a melamine resin, it exhibits excellent cleaning properties against dirt on the inner surface of the molding mold. The reason for this is not necessarily clear, but the methylol group of melamine resin has high polarity, and it is generated during molding and is a stain derived from a sealing molding material that adheres to the inner surface of the molding die (that is, a thermosetting resin composition). And the mold cleaning resin composition of the present invention can act, so that the mold cleaning resin composition containing a melamine resin has excellent performance. I think to show. Further, since the melamine-based resin is thermally stable, it is considered that excellent cleaning properties are stably exhibited even in the vicinity of 160 to 190 ° C., which is a temperature at the time of cleaning the mold.

-Inorganic filler-
The resin composition for mold cleaning of the present invention contains at least one spherical inorganic filler having a maximum particle size of 1 μm to 70 μm.

  The inorganic filler used in the present invention has a spherical shape. Spherical shape means that the average aspect ratio of the particle size of the inorganic filler described later is 1 to 1.5. In addition to perfect spheres, spheres that can be regarded as spheres such as cross-sectional ellipses with non-uniform cross-sectional diameters. A substantially spherical shape that is close to the shape is also included.

The average aspect ratio of the particle size of the inorganic filler is preferably 1 to 1.2. Therefore, the mold cleaning resin composition of the present invention can maintain the fluidity of the mold cleaning resin composition during cleaning. Furthermore, the resin composition for mold cleaning of the present invention is expected to have a good cleaning effect up to the corner portion of the densified mold cavity, and further suppresses wear and damage to the inner surface of the mold and the gate portion. Can do.
When the average aspect ratio of the particle size of the inorganic filler is 1.5 or less, the mold cleaning resin composition can maintain the fluidity of the mold cleaning resin composition at the time of cleaning. Good cleaning performance can be ensured up to the corner of the mold cavity. In addition, wear and damage to the inner surface of the molding die and the gate portion can be suppressed.

In the present invention, the aspect ratio of the particle size of the inorganic filler is determined as follows.
That is, the aspect ratio of the particle size of the inorganic filler can be obtained using an electron microscope in the same manner as the method for obtaining the particle size described later. Here, the major axis (X) of one inorganic filler and the minor axis (Y) orthogonal to the major axis (X) are each measured five times. From the measured value obtained, the aspect ratio of the particle diameter of one inorganic filler is determined by the following formula. However, the major axis (X) ≧ the minor axis (Y).
Aspect ratio of particle size = (average value of five measured values of X) / (average value of five measured values of Y)
And said aspect ratio was measured about each of 150 inorganic fillers, the average of the obtained measured value was calculated | required, and it was set as the aspect ratio of the particle | grains of an inorganic filler.

  According to the definition in the present invention, when the major axis (X) and the minor axis (Y) are equal, the aspect ratio of the particle size is 1. In the definition in the present invention, the aspect ratio of the particle size does not take a value less than 1. The shape of the inorganic filler is spherical, but the closer the spherical shape is, the closer the particle diameter aspect ratio is to 1. Even if the image of the inorganic filler in the electron microscope has a square shape, the aspect ratio of the particle size is 1, but the inorganic filler used in the present invention has a spherical shape (including a substantially spherical shape). In the present invention, when the aspect ratio of the particle size is close to 1, it indicates that it is close to a sphere.

  In the present invention, the average aspect ratio of the particle size of the inorganic filler is an average value of the aspect ratios of 150 inorganic fillers measured by the above method. In addition, the standard deviation of the aspect ratio of the inorganic filler described later is the standard deviation of the aspect ratio of the particle diameters of 150 inorganic fillers measured by the above method.

  The inorganic filler is, for example, one or more selected from the group consisting of silicon carbide, silicon oxide (silica), titanium carbide, titanium oxide, boron carbide, boron oxide, aluminum oxide, magnesium oxide, and calcium oxide. These inorganic fillers may be used alone or in combination.

  The inorganic filler in the present invention is preferably silicon oxide (silica) or titanium oxide, and particularly preferably silicon oxide. Although depending on the material and condition of the mold, as the inorganic filler used in the present invention, silicon oxide (silica) and titanium oxide are suitable in hardness, and the inner surface of the mold and the gate part are worn and damaged. It is preferable in that it can be suppressed. The inventor of the present invention considers that the inorganic filler is removed by physically polishing dirt on the surface of the mold when the densified mold cavity is cleaned. Further, silicon oxide (silica) and titanium oxide are preferable because they are thermally stable even in the vicinity of 160 to 190 ° C. when the mold is cleaned.

In the mold cleaning resin composition of the present invention, it is desirable that the standard deviation of the aspect ratio of the inorganic filler is 0.3 or less. Since the mold cleaning resin composition of the present invention has a standard deviation of the particle diameter aspect ratio of the inorganic filler of 0.3 or less, the fluidity of the mold cleaning resin composition is easily maintained during cleaning. Further, it becomes easy to obtain cleaning properties up to the corner of the mold cavity, and it is possible to further suppress wear and damage to the inner surface of the molding die and the gate portion.
Especially, as standard deviation of the aspect ratio of an inorganic filler, 0.15-0.3 is more preferable.

  In the above description, the “densified mold cavity” means that the arrangement of the cavities with respect to the entire molding die surface is densely and optimally arranged by reducing the size of the cavity. The fine mold cavity has a gate portion narrower than the conventional one due to the miniaturization of the cavity, and its narrowest is 100 μm.

The maximum particle size of the inorganic filler used in the present invention is 1 μm to 70 μm. In the resin composition for mold cleaning of the present invention, since the maximum particle size of the inorganic filler contained is in the range of 1 μm to 70 μm, a good cleaning effect can be obtained up to the corner portion of the densified mold cavity. . Here, the maximum particle size being 1 μm or more means that the inorganic filler has a shape that physically acts on the mold surface dirt. On the other hand, when the maximum particle diameter exceeds 70 μm, the particles of the inorganic filler are easily clogged in the cavity portion, the fluidity is lowered, and as a result, the cleaning effect is lowered.
Among them, the maximum particle size of the inorganic filler is more preferably 10 μm to 50 μm, particularly preferably 20 μm to 45 μm, and most preferably 45 μm.

The average particle size of the inorganic filler used in the present invention is desirably 4 μm to 10 μm. The inventor of the present invention believes that the inorganic filler having a remarkably small average particle size has a small mass and surface area, and therefore it is difficult to exhibit the cleaning performance of the mold cavity. In the mold cleaning resin composition of the present invention, when the average particle size of the inorganic filler is 4 μm or more, the cleaning property of the entire molding die is further obtained. In addition, when the average particle size of the inorganic filler is 10 μm or less, the cleaning properties up to the corner portion of the densified mold cavity can be further obtained. Furthermore, when the average particle size of the inorganic filler in the present invention is 10 μm or less, it is possible to further suppress wear and damage to the inner surface of the molding die and the gate portion.
Especially, as an average particle diameter of an inorganic filler, 5 micrometers-8 micrometers are more preferable.

The standard deviation of the particle size of the inorganic filler used in the present invention is desirably 7 μm or less. In the resin composition for mold cleaning of the present invention, when the standard deviation of the particle size of the inorganic filler is 7 μm or less, the fluidity of the resin composition for mold cleaning can be maintained at the time of cleaning. More cleanability up to the corners is obtained.
Especially, as a standard deviation of the particle size of an inorganic filler, 1 micrometer-7 micrometers are more preferable.

In the present invention, the particle size of the inorganic filler is determined as follows.
That is, using an electron microscope (product name: JSM-5510, manufactured by JEOL Ltd.), the inorganic filler is photographed at 1500 times so that approximately 30 inorganic fillers are included in one field of view. The diameters of the inorganic fillers in each of the five fields were measured. Subsequently, the major axis (X) of the inorganic filler and the minor axis (Y) orthogonal to the major axis (X) were measured, and the average value of five measurements was obtained. For a total of 150 inorganic fillers, X and Y are measured, the particle size of one inorganic filler is determined by the following formula, and the particle size (calculated value) of 150 inorganic fillers is averaged, The particle size of the inorganic filler was determined.
Particle size = ((average value of five measured values of X) + (average value of five measured values of Y)) / 2

  In the present invention, the average particle diameter is an average value of the particle diameters of 150 inorganic fillers measured by the above method. Moreover, the standard deviation of a particle size is a standard deviation of the particle size of 150 inorganic fillers measured by said method.

  The inorganic filler that can be suitably used in the present invention is, for example, amorphous spherical silica, and specifically, a product name manufactured by Nippon Steel & Sumikin Materials Co., Ltd. Micron Corporation (Nippon Steel Materials Co., Ltd. Micron Corporation). “S440-4”, “HS-202”, “HS-204”, “UF-320” and the like.

-Curing catalyst-
The resin composition for mold cleaning of the present invention contains at least one selected from myristic acid and stearic acid as a curing catalyst.
When the inorganic filler having a spherical shape (including a substantially spherical shape) and a maximum particle diameter of 1 μm to 70 μm is used for the mold cleaning resin composition, the mold cleaning resin cavity is made finer. When cleaning the mold, the flow of the mold cleaning resin composition becomes excessive, and the mold cleaning resin composition does not stay properly in the mold. By using myristic acid and / or stearic acid as a curing catalyst, the inventors of the present invention can prevent the flow of the mold cleaning resin composition from becoming excessive when the fine mold cavity is cleaned. I found out.
Therefore, the mold cleaning resin composition of the present invention can clean the corners of the fine mold cavity and remove the dirt by appropriately retaining the mold cleaning resin composition in the mold. Performance is also improved.

  The content of myristic acid and stearic acid used in the present invention is preferably 0.1 part by mass to 3.0 parts by mass, and 0.5 parts by mass with respect to 100 parts by mass of the melamine resin. 2.0 parts by mass is more preferable, and 1.0 to 2.0 parts by mass is particularly preferable. When the content of myristic acid is 0.1 parts by mass or more, the mold cleaning resin composition of the present invention is easily cured at the time of cleaning, and finer mold cavity dirt is better removed. . Moreover, it is more excellent in the storage stability of the resin composition for metal mold | die cleaning of this invention as the said myristic acid is 3.0 mass parts or less.

-Salts of saturated fatty acids and metals-
The resin composition for mold cleaning of the present invention contains zinc myristate as a salt of a saturated fatty acid and a metal. The inventor of the present invention believes that when a fine mold cavity is cleaned, a salt of a saturated fatty acid and a metal acts on the dirt, and for example, the dirt swells to facilitate separation from the surface of the mold. . That is, the inventor of the present invention selectively uses zinc myristate as a salt of a saturated fatty acid and a metal, so that the resin composition for cleaning a mold of the present invention can be used for cleaning a densified mold cavity. It was found that the flow of the is prevented from becoming excessive.

The melting point of zinc myristate is 123 ° C to 130 ° C. Moreover, the temperature at the time of the cleaning of the metal mold cavity which uses the sealing molding material containing a thermosetting resin composition is 160 to 190 degreeC normally.
The inventor of the present invention shows that the zinc myristate contained in the mold cleaning resin composition of the present invention exhibits appropriate fluidity in the range of 160 ° C. to 190 ° C. which is the cleaning work environment temperature. The flow of the mold cleaning resin composition is considered to be in a range suitable for cleaning.
Therefore, the mold cleaning resin composition of the present invention can clean the corners of the fine mold cavity and remove dirt by appropriately maintaining the mold cleaning resin composition in the mold. Performance is improved.

  As content of zinc myristate used as a salt of a saturated fatty acid and a metal, 0.1 part by mass to 3.0 parts by mass is preferable with respect to 100 parts by mass of the melamine resin, and 0.5 parts by mass to 2.0 parts by mass is more preferable, and 1.0 to 2.0 parts by mass is particularly preferable. When the content of zinc myristate is 0.1 parts by mass or more, the mold cleaning resin composition of the present invention is easily cured at the time of cleaning, and dirt in the fine mold cavity is satisfactorily removed. . Moreover, since content of zinc myristate is 3.0 mass parts or less, since the flow of the resin composition for metal mold | die cleaning of this invention does not become excess, it is preferable.

-Other additives-
The mold cleaning resin composition of the present invention may further contain other additives. Examples of other additives include colorants, antioxidants, lubricants, and the like.
Examples of the lubricant include, for example, fatty acid amide type lubricants, specifically, saturated or unsaturated monoamide type lubricants such as lauric acid amide, myristic acid amide, erucic acid amide, oleic acid amide, stearic acid amide, methylene bis stearic acid amide, ethylene Examples thereof include saturated or unsaturated bisamide type lubricants such as bisstearic acid amide and ethylene bisoleic acid amide.

  The resin composition for mold cleaning according to the present invention is used to remove dirt derived from a sealing molding material containing a thermosetting resin composition typified by epoxy resin, silicone resin, phenol resin, and polyimide resin. Suitable for removing from the surface.

  The mold cleaning resin composition of the present invention is prepared by almost uniformly mixing a melamine resin, an inorganic filler, a curing catalyst, a salt of a saturated fatty acid and a metal, and, if necessary, other additives. be able to. Examples of the method for mixing almost uniformly include a method using a kneader, a ribbon blender, a Henschel mixer, a ball mill, a roll kneading machine, a raking machine, a tumbler, and the like.

  The mold cleaning resin composition of the present invention is suitable for a transfer type mold cleaning resin composition used in a transfer molding machine.

  The resin composition for mold cleaning of the present invention is usually processed into a tablet shape and is usually used for cleaning work in a molding die. Specifically, after arranging the lead frame on the mold, the tablet-shaped mold cleaning resin composition is inserted into the pot portion, and after the mold is clamped, it is pushed away with a plunger. At this time, the resin flows from the gate portion into the mold cavity from the pot portion through the runner portion. The cleaning operation is performed by opening the mold after a predetermined molding time has elapsed, and removing the molded product including the mold cleaning resin composition and dirt integrated with the lead frame.

  The resin composition for mold cleaning of the present invention is suitably used for removing dirt in a molding die in a sealing molding operation such as an integrated circuit. The material of the molding die is, for example, iron or chrome. The inside of the molding die is usually plated. By repeating the sealing molding operation and the cleaning operation of the surface inside the molding die, micron-sized scratches are generated in the molding die, and the die is worn. Occurrence of such scratches and wear causes a lack of a plated surface in the molding die and a rough surface state. Due to the occurrence of internal flaws, the lack of plating surface on the inner surface of the molding die and the rough surface condition, the molding die suffers from deterioration of moldability and releasability during sealing molding work and poor surface appearance. Occur. Thereby, the malfunction which the cleaning workability | operativity in a shaping die loses further generate | occur | produces. In the resin composition for mold cleaning according to the present invention, by appropriately selecting the maximum particle size of the spherical (including substantially spherical) inorganic filler, it is possible to suppress damage in the molding die during cleaning.

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

Example 1
As the melamine-based resin, 21.3 parts by mass of a melamine-phenol cocondensate and 50 parts by mass of a melamine resin prepared by pulverizing a product obtained by heating and reacting by a known method and then drying under reduced pressure, and an amorphous filler as an inorganic filler Quality spherical silica (product name: S440-4, Nippon Steel & Sumikin Materials Co., Ltd., Micron Co., Ltd. (Inorganic filler manufactured by Nippon Steel Materials Co., Ltd.)) 20 parts by mass, and organic filler, hardwood pulp 7.8 0.5 parts by mass of zinc myristic acid as a salt of saturated fatty acid and metal, and 0.05 parts by mass of myristic acid as a curing catalyst were added to a ball mill and pulverized. Thereafter, stearamide as a lubricant was added by 0.35 parts by mass with a Nauter mixer. In this way, a mold cleaning resin composition was prepared.

  When the inorganic filler was observed with an electron microscope, the average aspect ratio of the particle size of S440-4 was 1.16 (spherical). Moreover, the average aspect ratio of any particle size of other inorganic fillers described later used in the examples was a sphere in the range of 1 to 1.5.

Table 1 below summarizes the composition and amount (parts by mass) of the mold cleaning resin composition prepared in Example 1, the average particle size, the maximum particle size, and the average aspect ratio of the inorganic filler.
The standard deviation of the particle size of the inorganic filler was 7 μm, and the standard deviation of the aspect ratio of the inorganic filler was 0.23.

  Moreover, cleaning property was evaluated by the test method shown below with respect to the produced resin composition for mold cleaning. The produced mold cleaning resin composition is a transfer type.

−Cleanability−
An automatic molding machine using a QFP (Quad Flat Package) mold was prepared, and 400 shots were performed at a mold temperature of 175 ° C. using a commercially available epoxy resin molding material EME-G700L (manufactured by Sumitomo Bakelite Co., Ltd.). Molding was performed, and stains were developed on the surface inside the molding die. Using this mold, a cleaning operation was performed by repeatedly molding the mold cleaning resin composition prepared above until the dirt on the inner surface could be removed. The mold cleaning resin composition was repeatedly molded at a mold temperature of 175 ° C. in the same manner as the molding of the epoxy resin molding material.
The gate portion of the mold cavity used for the evaluation had a width of 800 μm and a height of 300 μm. Further, the gate portion of this mold cavity was 100 μm at the narrowest portion.

In the evaluation of cleaning performance, paying particular attention to whether the gate part and corner part of the mold cavity can be cleaned, the removal of dirt at the corner part of the mold cavity and the gate part and corner part of the mold cavity are cleaned. This was done by determining the number of shots necessary to do this. The cleaning performance is better as the number of shots is smaller. Table 1 summarizes the evaluation results of the examples and comparative examples.
The removal of dirt at the corner was evaluated by visually confirming the presence or absence of dirt at the corner of the mold cavity. In the evaluation, the resin composition for mold cleaning passed well through the gate part of the mold cavity, and “A” was defined as “A” when there was no dirt or good with little dirt. The incoming one was judged as “B”.
In addition, when evaluating the number of shots required to clean the gate and corner of the mold cavity, the number of shots is recorded when the number of completed shots is 10 times or less, and dirt is removed even after 10 times of cleaning. When it was not possible, it was determined as “NG”.

(Example 2)
In Example 1, except that myristic acid used as the curing catalyst was replaced with stearic acid, a resin composition for mold cleaning was prepared and the cleaning property was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

(Examples 3 to 5)
A resin composition for mold cleaning was prepared in the same manner as in Example 1 except that the inorganic filler was changed as shown in Table 1 below, and the cleaning property was evaluated. The evaluation results are shown in Table 1.

(Comparative Example 1)
In Example 1, except that benzoic acid was used as the curing catalyst, a mold cleaning resin composition was prepared and the cleaning property was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

(Comparative Example 2)
In Example 1, except that zinc stearate was used as a salt of a saturated fatty acid and a metal, a mold cleaning resin composition was prepared and the cleaning property was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

(Comparative Example 3)
In Example 1, a resin composition for mold cleaning was used in the same manner as in Example 1 except that crystalline silica (product name: R-1) manufactured by Yamamori Civil Engineering Co., Ltd. was used as the inorganic filler. A product was prepared and the cleaning property was evaluated. The evaluation results are shown in Table 1.
The inorganic filler used in Comparative Example 3 has the particle size and aspect ratio shown in Table 1, and the shape of the inorganic filler was indeterminate when confirmed using an electron microscope. It was.

(Comparative Example 4)
In Example 1, a resin composition for mold cleaning was used in the same manner as in Example 1 except that crystalline silica (product name: pure meteorite powder) manufactured by Seto Ceramics Co., Ltd. was used as the inorganic filler. Were prepared and the cleaning property was evaluated. The evaluation results are shown in Table 1.
In addition, the inorganic filler used in Comparative Example 4 has a particle size and an aspect ratio shown in Table 1.

(Comparative Example 5)
A resin composition for mold cleaning was prepared in the same manner as in Example 1 except that the inorganic filler was changed as shown in Table 1 below, and the cleaning property was evaluated. The evaluation results are shown in Table 1.

The details of the inorganic filler in Table 1 are as follows.
S440-4: Amorphous spherical silica manufactured by Nippon Steel & Sumikin Materials Co., Ltd. Micron (Nippon Steel Materials Co., Ltd.) HS-202: Nippon Steel & Sumikin Materials Co., Ltd. Micron (Nippon Steel Materials Co., Ltd. Micron) ) Amorphous spherical silica manufactured by R-1: Crystalline silica manufactured by Yamamori Civil Engineering Co., Ltd. HS-302: Amorphous manufactured by Nippon Steel & Sumikin Materials Co., Ltd. Micron (Nippon Steel Materials Co., Ltd. Micron) Spherical silica UF-320: amorphous spherical silica manufactured by Tokuyama Corporation HS-204: amorphous spherical silica manufactured by Nippon Steel & Sumikin Materials Co., Ltd. (Micron Corporation) Powder: Crystalline silica manufactured by Seto Ceramics Co., Ltd.

  As shown in Table 1, the mold cleaning resin composition of the present invention was able to satisfactorily clean up to the corners of the densified mold cavity and improved the dirt removal performance.

  Moreover, as shown in Table 1, the resin composition for mold cleaning of Examples 1 to 5 includes a melamine resin, an inorganic filler having a spherical shape and a maximum particle size of 1 μm to 70 μm, and myristic acid or a curing catalyst. Since stearic acid and zinc myristic acid as a salt of saturated fatty acid and metal are included, the narrowest part of the gate part can be cleaned well to the corner part with a mold of 100 μm, and the number of cleaning completed shots is 4 Excellent dirt removal performance that can be done only once. Furthermore, when the mold surface after cleaning was observed, the mold cleaning resin compositions of Examples 1 to 5 did not damage the mold surface.

  On the other hand, since the mold cleaning resin composition of Comparative Example 1 contains benzoic acid as a curing catalyst, the flow of the mold cleaning resin composition was excessive, and the number of shots for cleaning completion increased. Therefore, the dirt removal performance was inferior to that of Example 1.

  The mold cleaning resin composition of Comparative Example 2 contained zinc stearate as a salt of a saturated fatty acid and a metal, so that the flow of the mold cleaning resin composition was excessive and the number of shots for cleaning completion increased. Therefore, the dirt removal performance was inferior to that of Example 1.

  In the resin composition for mold cleaning of Comparative Example 3, since the maximum particle size of the inorganic filler is 352 μm and is indefinite, the corner of the mold cavity cannot be cleaned, and the mold dirt removal performance Was also inferior.

  In the mold cleaning resin composition of Comparative Example 4, since the maximum particle size of the inorganic filler is 100 μm, even if the flow of the mold cleaning resin composition is appropriate, the corner of the mold cavity is cleaned. It was difficult. In addition, the mold removal performance was inferior.

  In the mold cleaning resin composition of Comparative Example 5, the maximum particle size of the inorganic filler is 75 μm, and there is a tendency that the particles tend to be clogged with each other, and good fluidity cannot be secured. The part could not be cleaned well. Therefore, the dirt removal performance of the mold was also inferior.

  As shown in the above Examples and Comparative Examples, when the maximum particle size of the inorganic filler is 1 μm to 70 μm, the mold cleaning is performed by appropriately selecting the curing catalyst and the salt of the saturated fatty acid and the metal. The flow at the time of cleaning with the resin composition can be controlled, and a good cleaning effect is exhibited up to the corner portion of the densified mold cavity. In addition, the mold cleaning resin composition remained properly in the mold, and the performance of removing dirt in the mold was improved.

  The mold cleaning resin composition of the present invention is a mold cleaning resin composition that removes dirt on a mold surface derived from a thermosetting resin composition, and is suitably used for transfer molding in a transfer mold molding machine. .

The disclosure of Japanese application 2012-011544 is incorporated herein by reference in its entirety.
All documents, patent applications, and technical standards mentioned in this specification are to the same extent as if each individual document, patent application, and technical standard were specifically and individually described to be incorporated by reference, Incorporated herein by reference.

Claims (3)

  Gold containing a melamine-based resin, a spherical inorganic filler having a maximum particle size of 1 μm to 70 μm, a curing catalyst selected from myristic acid and stearic acid, and zinc myristate that is a salt of a saturated fatty acid and a metal Resin composition for mold cleaning. Wherein the inorganic filler is a standard deviation of the particle size is not more 7μm or less, gold according to claim 1, wherein the average aspect ratio of grain size in the 1 to 1.2, the standard deviation of the aspect ratio of 0.3 or less Resin composition for mold cleaning.   The resin composition for mold cleaning according to claim 1 or 2, which is used in a transfer molding machine.