JPS63297005A - Porous mold and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a porous mold at low manufacture cost, while the time necessary for production is reduced by a method in which the mold is constituted of the filler in which the fine particles of metallic material or synthetic resin material are minutely packed and the matrix of thermosetting resin or reactive setting resin, and a plurality of vent holes are formed in the nonpacked part of the matrix. CONSTITUTION:A porous mold is constituted of the filler 8 in which the fine particles 8 composed of metallic material, inorganic material or synthetic resin material are minutely packed and the matrix 9 composed of thermosetting resin or reaction setting resin connecting the fine particles in nonpacking state. A plurality of vent holes 10 connecting the front surface of a porous form-body 11 to the rear surface thereof, are formed in the nonpacked part of the matrix 9. The plated layer 13 having a plural ity of vent holes 12 connected to the vent holes 10 is formed on the front surface of the porous form-body 11. The filler material and the matrix material are kneaded and agitated, and further diluted with organic solvent. A moded 15 is coated with said material, and then is dried and cured, thereby forming the porous form-body 11. From the rear surface of the porous form-body 11, gas is blown thereinto, whereby the front surface of the porous form-body 11 is plated.

Description

DETAILED DESCRIPTION OF THE INVENTION Purpose of the Invention (Field of Industrial Application) The present invention relates to a porous gas-permeable material used in synthetic resin molding such as vacuum molding, blow molding, injection molding, and reaction injection molding (RIM). It concerns molds and their manufacturing methods.

(Prior art) Conventional porous molds of this type include those made by punching a large number of ventilation holes in a mold formed by die-sinking, electroforming, 1I dense casting, etc. by laser machining, electrical discharge machining, etc.; There are various types, including those in which the ventilation holes themselves are formed by electroforming.

Among these, those using electroforming in particular require only about 20 days for electroforming, which has the advantage of shortening the delivery time compared to other porous molds made by die-sinking or the like.

(Problem to be solved by the invention) However, in recent years, as the trend towards high-mix, low-volume production has become stronger, demands for shorter delivery times and lower costs for molds have become stronger. by (
There were limits to meeting these demands (not only by die engraving but also by electroforming).

An object of the present invention is to provide a completely new porous type that can significantly shorten the time required for manufacturing and greatly reduce manufacturing costs.

Structure of the Invention (Means for Solving the Problems) The porous type of the first invention includes a filler in which fine particles made of a metal material, an inorganic material, or a synthetic resin material are packed in a nearly dense state, and fine particles of the filler. A matrix made of a thermosetting resin or a reactive hardening resin that bonds between the fine particles in an unfilled state, and a large number of air passages communicating from the front surface to the back surface of the porous body are formed in the unfilled portions of the matrix between the fine particles. It consists of a structure in which .

Further, the porous type manufacturing method of the second invention uses fine particles made of a metal material, an inorganic material, or a synthetic resin material as a filler material, and a liquid thermosetting resin or a reactive hardening resin as a matrix material. a mixing step of mixing and stirring; a diluting step of diluting this mixture with a proprietary solvent;
The method consists of a coating step in which the diluted mixture is applied to the model, and a forming step in which the applied mixture is dried and hardened to form a porous body.

(Function) In the first invention, the filler acts as a material that forms the porous body to a predetermined thickness, and the matrix acts to maintain the shape of the porous body by firmly bonding between the fine particles of the filler. do. Further, the large number of air passages formed between the fine particles makes the porous body porous and acts as holes through which gas for sucking the molded object flows.

In the second invention, the filler material and the matrix material are uniformly mixed in the mixing step, and the outer surface of the filler fine particles is thinly covered with the matrix material. Further, the viscosity of the mixture is reduced by the dilution step, making it easier to carry out the next coating step and allowing uniform coating. Also,
The coating process allows the shape of the model to be easily transferred to the porous body in an extremely short time. Then, in the forming process, the fine particles of the filler are bonded together by the matrix, and a ventilation path is formed.

(Example) Hereinafter, an example in which the present invention is embodied in a porous mold for vacuum forming a synthetic resin sheet will be described with reference to the drawings.

As shown in FIG. 2, the porous mold device 1 of this embodiment includes a porous mold 2, a support frame 3 for supporting the porous mold 2, and a support frame 3 that is airtightly attached to the bottom surface of the support frame 3. The bottom plate 4 is provided with a plug 4a to which a vacuum pump 19 is connected during vacuum forming.

The porous mold 2 is formed into a thin wall with a thickness of about 5 to 10 m, and has a recess 6 for shaping the synthetic resin sheet 5. Further, on the surface of the porous mold 2, a concavo-convex pattern 7 is formed for transferring the concave-convex pattern onto the surface of the synthetic resin sheet 5.

As shown in FIG. 3, the porous type 2 has a filler 8 which is almost densely packed with fine particles 8a made of a metal material, an inorganic material, or a synthetic resin material, and a space between the fine particles 8a of the filler 8 is not filled. It is formed from a matrix 9 made of a thermosetting resin or a reaction-curing resin that binds to the porous mold 2, and further, in the areas between the fine particles 8a where the matrix 9 is not filled, the porous mold 2 is finely detoured from the front surface to the back surface. A porous air-permeable main body 11 in which a large number of communicating air passages 10 are formed; Breathable porous plating layer 1
It is composed of 3.

The filler 8 includes ■aluminum, magnesium,
Metal materials such as titanium, nickel, copper, zinc, iron, other metals, their alloys, and composite materials of these and inorganic materials, aluminum oxide, silicon oxide, stabilized zirconia, silicon nitride, silicon carbide Inorganic materials such as ceramics and glass, or ■phenol resin, epoxy resin, etc.
Fine particles 8a made of a synthetic resin material such as a composite resin filled with glass fiber or the like are used alternatively or in combination.

In this embodiment, aluminum fine particles 8a are used.

The average particle diameter of the fine particles 8a is not particularly limited, but is generally preferably 50 μm to 200 μm. 50μm
If it is smaller, the air passage 10 becomes narrower and the air permeability decreases,
This is because if it is larger than 200 μm, irregularities due to the fine particles 8a will appear on the surface of the synthetic resin sheet 5 to be vacuum formed, which may deteriorate the appearance. When forming the uneven pattern 7 on the surface of the porous mold 2 as in this embodiment, 50μ
It is preferable to use fine particles 8a having a small particle size of about m.

Furthermore, if the fine particles 8a contain a reinforcing material such as ceramic fiber, carbon fiber, or metal fiber with an aspect ratio of 15% to 20% as the filler 8, the reinforcing material will increase the bonding force between the fillers 8. , the strength of the porous type 2 is improved.

Further, for the matrix 9, a thermosetting resin such as a phenol resin, a reaction curing resin such as an epoxy resin, or a urethane resin is used. In this embodiment, epoxy resin is used.

The mixing ratio of the filler 8 and the matrix 9 is not particularly limited as it depends on the type and particle size of each material, but
Generally, a weight ratio of 5:1 to 20:1 is preferred. If the amount of filler 8 is less than this range, the spaces between the fine particles 88 of the filler 8 may be filled with matrix 9, reducing air permeability.On the other hand, if the amount of filler 8 is too large, the bonding force between the fine particles 8a may be weakened. This is because the strength of the porous type 2 decreases. In this embodiment, this weight ratio is 10:1.

As the material for the plating layer 13, nickel, cobalt, copper, silver, nickel-phosphorus, nickel-boron, cobalt-phosphorus, etc. are used when electroless plating is used. especially,
The latter three are preferred because they have excellent corrosion resistance and wear resistance. Furthermore, in the case of vapor phase plating, almost all metals and alloys can be used. In this embodiment, electroless plating of nickel-phosphorus is used.

In the above porous type 2, the filler 8 is
The matrix 9 acts as a material for forming the filler 8 to a predetermined thickness, and the matrix 9 acts to firmly bond the fine particles 8a of the filler 8 to maintain the shape of the porous mold 2. In addition, a large number of air passages 10 formed between the fine particles 8a make the porous mold 2 breathable and act as holes through which air for sucking the molded object (here, the synthetic resin sheet 5) flows. do.

Next, a method for manufacturing the porous mold 2 will be explained step by step.

■ First, as shown in FIG.
A liquid thermosetting resin or a reactive hardening resin (here, epoxy resin) as a material is mixed at a predetermined mixing ratio (here, 10:1) in the mixing container 14 and stirred (mixing step). Through this mixing step, the filler material and the matrix material are mixed uniformly, and the outer surface of the fine particles 8a of the filler 8 is thinly covered with the matrix material.

(2) Next, as shown in FIG. 5, the mixture of filler material and matrix material is diluted with an organic solvent 18 (dilution step). Alcohols, aromatic hydrocarbons, etc. are used as the organic solvent 18. This dilution step lowers the viscosity of the mixture, making it easier to carry out the next coating step, and enabling uniform coating.

(2) Next, as shown in FIG. 6, the diluted mixture is applied to the model 15 by a spray coating method (coating step). This model 15 is, of course, formed to have the same shape as the synthetic resin sheet 5 after shaping, and has an uneven pattern 15a on its surface for providing the uneven pattern 7 on the porous mold 2. Through this coating process, the shape of the model 15 is changed to the porous type 2.
can be copied easily and in a very short time.

(2) Next, the applied mixture is dried and hardened to form the porous mold main body 11, and this is released from the model 15 (forming step, not shown). Through this formation process, as shown in FIG. 3, the fine particles 8a of the filler 8 are bonded together by the matrix 9, and the air passages 10 are formed, so that the porous body 11 with air permeability is formed in a short time. It is formed.

■ Next, as shown in FIG. 1, the support frame 3 and the bottom plate 4 are attached to the formed porous mold main body 11 in an airtight manner, and the periphery of the porous mold main body 11 is sealed with a storage wall member 16. surround. Then, a compressed air pump (not shown) is connected to the plug 4a of the bottom plate 4 to compress air on the back side of the porous type main body 11, and countless fine particles 8a are lined up on the surface of the porous type main body 11.
The surface side of the porous body 11 is filled with an electroless plating solution 17 for nickel-phosphorus plating while blowing out air through the air passages 10 between the two (plating process). Therefore, the electroless plating solution 17 hardly leaks to the back surface of the porous main body 11.

As a result, nickel-phosphorus adheres to the surface of the porous body 11 by chemical reduction to form a uniform plating layer 13, and the outlet of the air passage 10 from which air is blown is not plated, leaving the air hole 12 is formed. This plating process easily forms an effective plating layer 13 that is hard, has excellent durability, and does not block the ventilation passages 10 because it has the ventilation holes 12. In addition, plating layer 13
Since a part of the filler 8 enters between the fine particles 8a of the filler 8 on the surface, the bonding force between the fine particles 8a increases.

(2) The porous mold device 1 is completed by attaching the support frame 3 and the bottom plate 4 to the porous mold 2 manufactured as described above.

According to the porous mold 2 configured as described above and the manufacturing method thereof, manufacturing becomes easy and the time required for the manufacturing can be significantly shortened. For example, if the conventional electroforming method takes 20 days (although it is quite fast), the present porous type 2 can be manufactured in about 3 days, making it possible to significantly shorten the delivery time.

In addition, according to this porous type 2, manufacturing costs, which account for most of the product costs, can be significantly reduced.
An inexpensive porous type 2 can be provided. As described above, the present invention is extremely useful in meeting the industry's demands for shorter delivery times and lower costs.

Furthermore, since the porous mold 2 of this embodiment has the plating layer 13 on its surface, the surface has excellent wear resistance and is highly durable.

It should be noted that the present invention is not limited to the configuration of the above-mentioned embodiments, and may be modified and embodied as desired without departing from the spirit of the invention, for example, as described below.

(1) The plating layer 13 (and its plating process) in the porous type 2 can also be omitted.

In this case, the durability is lower than when the plating layer 13 is present, but it can be used as a porous type for prototyping or small-scale production, for example.

(2) The plating layer 13 can also be formed by vapor phase plating such as vacuum evaporation or sputtering. In this case as well, plating is performed while blowing gas from the back surface of the porous type main body 11 to the front surface.

(3) The present invention is applicable not only to porous molds for vacuum forming, but also to
It can also be embodied in porous molds for blow molding, injection molding, reaction injection molding (RIM), and other various moldings.

Effects of the Invention As detailed above, the present invention has excellent effects in that it is easy to manufacture, can shorten the manufacturing time, and can provide an inexpensive porous mold with a short delivery time.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view showing the plating process of an embodiment of the present invention, FIG. 2 is a sectional view showing the entire porous type device, and FIG. 3 is a partially enlarged sectional view of the same porous type.
FIG. 4 is a cross-sectional view showing the mixing step, FIG. 5 is a cross-sectional view showing the dilution step, and FIG. 6 is a perspective view showing the coating step. 2...Porous type, 8...Filler, 8a...Fine particles, 9...Matrix, 10...Air passage, 1
1...Porous type main body, 12...Vent hole, 13...
・Plating layer, 15...Model.

Claims (1)

[Claims] 1. Filler (8) filled with fine particles (8a) made of a metal material, an inorganic material, or a synthetic resin material in a substantially dense state
and a matrix (9) made of a thermosetting resin or a reactive hardening resin that bonds the fine particles (8a) of the filler (8) in an unfilled state, and the fine particles (8a)
A porous type in which a large number of air passages (10) communicating from the front surface to the back surface of the porous body (11) are formed in the unfilled portion of the matrix (9) in between. 2. According to claim 1, a plating layer (13) having a large number of ventilation holes (12) communicating with the ventilation path (10) is formed on the surface of the porous main body (11). Porous type as described. 3. The average particle size of the filler (8) is 50 μm to 200 μm.
The porous type according to claim 1, which has a diameter of μm. 4. The porous type according to claim 1, wherein the filler (8) contains a reinforcing material having an aspect ratio of 15% to 20% or more. 5. The porous type according to claim 1, wherein the mixing ratio of the filler (8) and the matrix (9) is 5:1 to 20:1 by weight. 6. A mixing step of mixing and stirring fine particles (8a) made of a metal material, an inorganic material, or a synthetic resin material as a filler material and a liquid thermosetting resin or a reaction curable resin as a matrix material; a dilution step of diluting the mixture of filler material and matrix material with an organic solvent; a coating step of applying the diluted mixture to the model (15); and a porous body (11) by drying and hardening the applied mixture. A method for manufacturing a porous mold comprising a forming step of forming a porous mold. 7. The forming step includes forming a porous body (11
7. The method of manufacturing a porous mold according to claim 6, which includes a plating step of plating the surface of the porous body (11) while blowing gas from the back surface to the front surface of the porous mold body (11).