KR20090073492A - Metal adhesive moulding method and the product made by the method - Google Patents

Abstract

A metal adhesive molding method and a product made by the method are provided to obtain a rigid metal-attached molded product by using an adhesive to join a molded resin material to a metal material. A metal adhesive molding method comprises a step of inserting a metal material in an injection mold after coating the metal surface with an adhesive, and a step of injecting a mixture of synthetic resin 50~90wt.% and glass fiber 10~50wt.% directly onto the metal surface. The adhesive is composed of polyamide 70~80wt.%, petroleum resin 10~20wt.%, mineral oil 2~7wt.%, and amino silane 3~7wt.%.

Description

Metal Bonding Molding Method and Metal Bonding Molding {METAL ADHESIVE MOULDING METHOD AND THE PRODUCT MADE BY THE METHOD}

The present invention relates to a metal adhesive molding method and a metal adhesive molding using an adhesive, and more particularly to a metal adhesive molding method and a metal adhesive molding that can suppress the tendency of separation between the metal and the resin during injection.

Conventionally, when combining a metal made of a material such as stainless steel (SUS) or aluminum (Al) and a resin made of a material such as polycarbonate (PC), the insert injection method was used a lot, but due to the heterogeneity of the material to be joined It was often separated after the process.

In order to prevent this, there is disclosed a double bonding method for joining a metal and a resin injection molding using a heat-sealed tape, and the schematic configuration thereof will be described in order with reference to FIG. 1.

① First, the metal is molded into a predetermined shape by forming through a press or cutting through a lathe.

(2) Then, prepare a heat sealing tape.

③ Next, a resin injection product of a predetermined shape is prepared through general injection.

④ Attach the heat sealing tape to the formed metal.

(5) Finally, the resin injection molded product is brought into contact with the heat-sealed tape, and then heat-welded.

However, in such a case, the adhesive force to the metal of the resin injection may be increased, but there is a problem in that the number of processes, manpower, and costs accordingly increase due to the use of heat-sealed tape.

In addition, when the shape of the metal base material is somewhat complicated, it is also difficult to apply the heat-sealing tape uniformly.

The present invention has been made to solve the above-described problems, an object of the present invention is to provide a metal adhesive molding method and a metal adhesive molding that can be firmly bonded to the resin injection molding to a metal of a predetermined shape in a simple process.

In order to achieve the above object, the metal adhesive molding method according to the present invention,

After inserting into the injection mold with the adhesive applied to the surface of the metal, the mixture of 50 ~ 90wt% synthetic resin and 10 ~ 50wt% glass fiber is directly injected to the surface of the metal coated with the adhesive It is characterized by.

Here, the adhesive is characterized in that consisting of 70 to 80wt% polyamide, 10 to 20wt% petroleum resin, 2 to 7wt% mineral oil, 3 to 7wt% amino silane.

And, the metal is characterized in that any one selected from stainless steel (SUS), aluminum (Al), titanium (Ti), magnesium (Mg), zinc (Zn).

In addition, the synthetic resin is characterized in that any one selected from polycarbonate (PC), acrylic, ABS and PPA (Polyphthalamide).

In addition, the adhesive is dried at room temperature for 20 minutes or more after application, and characterized in that the injection in a state maintained for 20 to 40 minutes at a temperature of 100 ~ 120 ℃.

Moreover, the coating thickness of the said adhesive is characterized by being in the range of 40-80 micrometers.

In addition, as the injection conditions, the temperature of the injection cylinder is in the range of 280 ~ 300 ℃, the injection cylinder 58 ~ 65kgf / cm ² , characterized in that the mold temperature 65 ~ 95 ℃ and cooling holding time 8 seconds or more.

On the other hand, the present invention is a metal adhesive molding comprising a surface of a metal and a mixture of synthetic resin-glass fiber attached by an adhesive, characterized in that made by the above-mentioned metal adhesive molding method.

According to the present invention having the configuration described above, there is an advantage that the resin injection molded product can be firmly bonded to the metal having a predetermined shape by the adhesive, thereby obtaining a rigid metal bonded molding.

In addition, according to the present invention, the process is simple compared to the conventional has the advantage of reducing the number of processes and manpower and the cost accordingly.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

As shown in Figure 1, the metal adhesive molding method using the adhesive according to the present invention, by first forming a metal to be combined with the resin and then applying the adhesive liquid to the metal, and then inserting the applied metal into the injection mold It consists of direct injection.

In this case, the metal may be stainless steel (SUS), aluminum, or the like, and the metal may be formed by a general molding method such as press forming, cutting, or casting.

In addition, in the embodiment of the present invention, a polycarbonate (PC) -glass fiber mixture is used as the mixture of the synthetic resin-glass fiber injected on the surface of the metal.

Since polycarbonate as a synthetic resin has a large shrinkage rate, when used alone, a gap is generated between the corner of the product and the metal after injection. In particular, when the thickness of the metal is thin, a phenomenon in which the metal is bent due to attraction force when shrinking the polycarbonate occurs. In addition, since the polycarbonate has a property that pores disappear when quenched at a high temperature, it is limited to the adhesive strength with the metal by the adhesive described later.

Therefore, the inclusion of a predetermined amount of glass fiber can compensate for the disadvantages in the injection of the aforementioned polycarbonate.

That is, because the glass fiber itself is a material with a very small shrinkage rate, when it is mixed with the synthetic resin and injected, there is no gap between the joining metals and even when a thin metal is used, warpage does not occur.

In addition, the glass fiber is cured while a certain gap occurs in the synthetic resin because the glass component contains a certain amount of the glass component, so that it can be tangled with the adhesive described later in the curing process to achieve a predetermined adhesive strength. In addition, when glass fiber is included, durability is superior to that of the synthetic resin itself, and since the particles are larger than pure synthetic resin, the occurrence of BURR is relatively low and easy to be injected during injection.

Synthetic resin in the mixture of the synthetic resin-glass fiber is preferably contained 50 to 90wt%, 10 to 50wt% glass fiber.

If the glass fiber is less than 10wt%, the above-described synthetic resin complementary effects are not sufficiently produced, and various disadvantages continue to occur. That is, the shrinkage rate is still large, causing a gap between the edge of the product and the metal, and warping occurs when applied to a thin metal.

On the other hand, when the glass fiber exceeds 50%, the life of the injection cylinder cylinder is shortened due to the glass fiber particles, the injection flowability is lowered, and the flexibility of the synthetic resin is lost easily broken. In addition, when high pressure and temperature are applied to improve injection flowability, there is a disadvantage in that economic efficiency is low.

The adhesive is composed of 70 to 80 wt% of polyamide, 10 to 20 wt% of petroleum resin, 2 to 7 wt% of mineral oil, and 3 to 7 wt% of amino silane.

First, the polyamide induces adhesion as a base resin, enables adhesion to a wide range of surfaces, and facilitates adhesion of heterogeneous surfaces (SUS + PC, Al + PE, etc.) having a large surface energy difference. If the polyamide is less than 70wt%, the effect is not sufficient, and if it exceeds 80wt%, there is no further effect increase, so the composition ratio of 70 to 80wt% is preferable.

Next, petroleum resin serves as a tackifying resin to lower the melting temperature of the adhesive and to provide a functional group in some cases, thereby improving the initial wetting and adhesion strength and controlling the solidification time. do. If the petroleum resin is less than 10wt%, the above-mentioned effect does not appear, and if it exceeds 20wt%, the result is that only the relative content of polyamide is reduced without further improving the effect, so that the composition ratio is 10 to 20wt%. Here, wettability refers to a property in which an adhesive is entangled while being spread on a surface of a plastic injection molded product.

The petroleum resin is an oil produced as a by-product of petroleum refining or petrochemical processes, and generically refers to plastics polymerized by various methods, containing olefins or diolefins as raw materials.

Next, the mineral oil is a plasticizer, which performs a lubrication role of the mixed resin to even out the flowability and distribution of the mixture and prevent the mixture from biasing a part of the product. If the content is less than 2wt%, there is a problem such as disturbing the flow of the resin and twisting the final product, if the content exceeds 7wt%, the fluidity is excessive and the resin overflows from the mold during the injection process.

In addition, the amino silane is an adhesive promoter (hardener) or the like, and serves to improve adhesion between the base metal of the metal and the resin and to improve the wetting between the resin and the inorganic material. Since amino silane can change the adhesion, curing time and mechanical strength greatly depending on the amount of usage, it is necessary to pay attention to the usage. 3 to 7 wt% is preferable as a composition ratio that can satisfactorily satisfy these properties. Do.

After applying the adhesive is dried at room temperature for 20 minutes or more and maintained for 20 to 40 minutes at a temperature of 100 ~ 120 ℃ it can exhibit the maximum adhesive strength. This is because if the adhesive curing temperature is too low or the curing time is too short, the adhesive may drop out or overflow. If the curing temperature is too high or the curing time is too long, premature curing or some curing before injection may occur, resulting in weak adhesive strength. to be. In addition, when the room temperature drying time is short, bubbles are generated in the adhesive, resulting in poor adhesion.

Moreover, it is preferable that the application | coating thickness of the said adhesive exists in the range of 40-80 micrometers. If the coating thickness is too small, the part that does not come into contact with the resin partially occurs during the injection process at high temperature, the adhesive strength is lowered. If the coating thickness is too thick, the adhesive falls off and overflows from the mold to reduce the adhesive strength or included in the mixture This can be adversely affected.

The adhesive is prepared by conventional mixing. That is, all four components described above are put into a container and then mixed and manufactured by stirring with a general stirrer. In addition, the adhesive may be stored in a sealed container at room temperature.

The adhesive used in the present invention is a thermosetting resin, and when a temperature of 100 ° C. or more is applied to the applied adhesive, the adhesive is cured to maintain strong adhesion with the metal.

In addition, the adhesive in the present invention remains cured for approximately 10 days after application to the metal. That is, if the injection within 10 days after coating can be obtained an injection molding having a predetermined adhesive strength.

Therefore, when the adhesive is applied to the metal base material, dried and then packaged and injected within 10 days, a predetermined adhesive force can be exhibited.

The adhesive force measurement of the adhesive is performed by measuring the force (or pressure) required to separate the synthetic resin-glass fiber mixture and the metal base material which have been injected by using a vacuum nozzle.

On the other hand, it is preferable that the temperature of a cylinder exists in the range of 280-300 degreeC so that resin may have appropriate fluidity at the time of injection. That is, if the temperature is too low, it hardens quickly and hardens before molding. If the temperature is too high, the adhesive melts and falls off from the base material, thereby adversely affecting the quality of the injected product.

In addition, the pressure of the injection cylinder is preferably in the range of 58 ~ 65kgf / cm ² . If the pressure of the injection cylinder is too small, the shape of the injection molded product is not completely molded and the adhesive strength is weak, if too large, the adhesive overflow occurs.

The metal bonding molding method may be a mold temperature of 65 to 95 ° C. and a cooling holding time of 8 to 20 seconds. This is because, if the mold temperature is too low, the problem of injection unmolding that hardens before the molding is completed occurs. If the mold temperature is too high, the adhesion between the base material and the resin is weakened because the adhesive material is dropped or overflowed. In addition, if the cooling holding time is too short, there is a problem of deformation before the mixture of the synthetic resin-glass fiber is hardened, and if it is too long, the productivity decreases. In other words, the cooling holding time may be set to 8 seconds or more, regardless of the productivity.

The injection liquid of the resin-glass fiber mixture may be filled into the mold in the range of approximately 1.5 to 3 seconds.

Example  One

[Table 1] below shows the results of testing the adhesion by combining a mixture of polycarbonate (PC) -glass fiber to a stainless steel (SUS) base material, but different components of the adhesive. All conditions except the composition of the adhesive in the test were kept the same.

In the table, # 1 and # 2 represent examples of the present invention, and # 3 to # 10 represent comparative examples.

In the case of the present invention # 1 and # 2 was excellent adhesion and no other disadvantages.

However, in the case of basic resins lacking or excessive # 3 and # 4, the adhesive did not exhibit uniform adhesion to the SUS and PC-glass fiber mixtures, and the adhesive remained as impurities in the mixture upon desorption.

In addition, in the case of insufficient petroleum resin or excessive # 5 and # 6, the wettability of the adhesive against SUS is not sufficient, so that the adhesive force is not uniformly realized on the mixture of SUS and PC-glass fiber, and the adhesive is impurity in the mixture when desorption. It remained as.

In addition, in case of # 7 lacking mineral oil, it was difficult to apply uniformly because the fluidity of the coating was not good due to the lack of the plasticizer for diffusing the adhesive, and thus the workability was not good.

In addition, in the case of # 8 excessive mineral oil, there are many plasticizers to diffuse the adhesive, so the fluidity of the coating is excessive, the adhesive overflows, the adhesive leaks during injection, resulting in poor workability.

In addition, in case of # 9 lacking an aminosilane as a curing agent, the secondary injection operation was not possible because it was not cured and remained in a liquid state.

In addition, in case of excessive # 10 of the aminosilane, which is a curing agent, the injection hardened the adhesive already to some extent, so that the holding force of SUS and the mixture of PC-glass fibers decreased relatively. Accordingly, a phenomenon in which the adhesive fell off while detaching occurred.

Example  2

Table 2 below shows the injection of a mixture of polycarbonate-glass fibers into stainless steel, but the adhesive having a composition of 75 wt% polyamide, 15 wt% petroleum resin, 5 wt% mineral oil, and 5 wt% amino silane was injected according to the eight conditions of use. The test results are shown.

Here, except for # 1, the rest corresponds to a comparative example.

As shown in Table 2, when the adhesive according to the conditions of the present invention is applied, the adhesive force is maintained, but most of the disadvantages appear when the conditions are out of the condition. Disadvantage was shown through the test example, but there was also the case where the predetermined adhesive force was maintained (# 6 condition).

Example  3

Table 3 below, injecting a mixture of polycarbonate-glass fiber to stainless steel, but the adhesive having a composition of 75wt% polyamide, 15wt% petroleum resin, 5wt% mineral oil, 5wt% amino silane according to the seven injection molding conditions The result of the injection test is shown.

Here, except the # 1 test, the rest is a comparative example.

As shown in Table 3, when the adhesive according to the injection conditions of the present invention is applied, the adhesive strength is maintained and does not appear, but most of the disadvantages appear when out of the conditions. Disadvantages were shown through the test examples, but there were also cases where the predetermined adhesive strength was maintained (# 3, # 5 conditions). However, in the case of # 3, the adhesive overflowed, and in the case of # 5, the cooling time is long, and thus there is a problem in that productivity decreases.

The above embodiment relates to the combination of SUS and PC-glass fiber mixture, but any one of Al, Ti, Mg, Zn, and Ni may be selected as the metal, and acrylic, ABS, or PPA (Polyphthalamide) may be selected as the synthetic resin. Similar results were obtained in the case.

1 is a process chart showing an example of a conventional metal adhesive molding method.

2 is a process chart showing a metal adhesive molding method using an adhesive according to the present invention.

Claims (8)

After inserting into the injection mold in the state where the adhesive is applied to the surface of the metal, the mixture of 50 ~ 90wt% synthetic resin and 10 ~ 50wt% glass fiber is characterized in that the direct injection on the surface of the metal coated with the adhesive Metal adhesive molding method using an adhesive. The method of claim 1, The adhesive is a metal adhesive molding method using an adhesive, characterized in that consisting of polyamide 70 ~ 80wt%, petroleum resin 10 ~ 20wt%, mineral oil 2 ~ 7wt%, amino silane 3 ~ 7wt%. The method of claim 1, The metal is a metal adhesive molding method using an adhesive, characterized in that any one selected from stainless steel (SUS), aluminum (Al), titanium (Ti), magnesium (Mg), zinc (Zn). The method of claim 1, The synthetic resin is a metal adhesive molding method using an adhesive, characterized in that any one selected from polycarbonate (PC), acrylic, ABS and PPA. The method according to any one of claims 1 to 4, The adhesive is a metal adhesive molding method using an adhesive, characterized in that the injection is dried at room temperature for at least 20 minutes after application, and maintained for 20 to 40 minutes at a temperature of 100 ~ 120 ℃. The method of claim 5, Coating thickness of the adhesive is a metal adhesive molding method using an adhesive, characterized in that in the range of 40 ~ 80㎛. The method according to any one of claims 1 to 4, Injection cylinder temperature is 280 ~ 300 ℃, injection cylinder pressure is in the range of 58 ~ 65kgf / cm ² , the metal adhesive molding method using an adhesive, characterized in that the mold temperature 65 ~ 95 ℃ and cooling holding time 8 seconds or more. . A metal adhesive molding comprising a surface of a metal and a mixture of a resin-glass fiber attached by an adhesive, the metal being produced by the metal adhesive molding method according to any one of claims 1 to 4. Adhesive moldings.

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