JP3254249B2 - Method for bluing transparent resin molded products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for bluing a transparent resin molded product.

[0002]

2. Description of the Related Art At present, transparent resin molded products made of PP and visible from outside can be used frequently, such as storage boxes used for storing clothing items and the like. When molding this transparent resin molded product, a technique is used in which a very small amount of a blue pigment is mixed into the molded product, thereby increasing the apparent coolness, as is called so-called bluing. At the time of bluing, a small amount of blue pigment is added to the PP raw material in advance, and the mixture is kneaded with an extruder to produce pellets, and the pellets are used to form a molded product using a molding machine. As a result, a predetermined amount of blue pigment is mixed into the molded article, and it is possible to improve the apparent refreshing feeling.

[0003]

As described above, conventionally, when performing bluing, it is necessary to knead a blue pigment before molding. Moreover, when performing bluing, since the content of the blue pigment per product must be changed according to the thickness of the product, the mixing amount of the blue pigment is changed for each product to be molded, It is necessary to knead the pigment, and the process for performing blueing becomes complicated.

[0004] In the step of producing the pellets, the amount of pigment used is very small, and the degree of coloring of each production rod is large, and it is extremely difficult to maintain a constant quality. That is, since the pigment required for bluing is very small for one product, if the blue pigment is excessively mixed, a product with a refreshing feeling is rather formed and the blue pigment is formed. If too little is mixed, a product that does not have the required refreshing sensation is formed, and the actual yield of the product is reduced.

The present invention has been made in view of such a conventional problem, and does not involve the mixing of blue pigment in the pre-forming step, and furthermore, mixes an appropriate amount of blue pigment per product. It is an object of the present invention to provide a method for bluing a transparent resin molded product capable of molding a transparent resin molded product blued with good yield.

[0006]

In order to solve the above-mentioned problems, the present invention provides a method for forming a transparent resin molded article,
The amount of the liquid pigment that is set in advance for each shot
Into the heating screw of the injection molding machine
Then, after mixing with the resin melted in the heating screw,
The liquid pigment is configured to be injected into a mold ;
It consists of 5 to 97% by weight of surfactant and 3 to 5% by weight of pigment. Further, the pigment is an inorganic ultramarine blue pigment, and further, the liquid pigment is mixed with a liquid antistatic agent to form a mixed liquid, and the mixed liquid is injected into the heating screw. The liquid mixture is configured so that the liquid pigment is mixed in an amount of 5 to 15% by weight with respect to the antistatic agent, and the mixed liquid is injected in an amount of 0.1 to 0.5% by weight with respect to the molded article. It is configured as follows.

[0007]

In the above construction, the amount of the blue liquid pigment is a predetermined amount for each shot when the resin molded article is molded .
Into the heating screw of the injection molding machine
Mixed with the resin that is injected and melted in the heating screw
After the injection into the mold, it is not necessary to knead or blend the pigment in the molding resin in advance. Also,
By appropriately setting the injection amount, it is possible to inject an appropriate amount of pigment according to the thickness of the product. Here, when the pigment is an inorganic ultramarine blue dye, the bluing effect becomes remarkable. .

[0008] Further, a pigment is mixed with a liquid antistatic agent to form a mixed liquid, and the mixed liquid is formed in a heating screw at the time of molding .
By injecting the, small amounts of pigment can be uniformly mixed throughout the product, it occurs uniformly bluing effect throughout evenly product. The liquid mixture is obtained by mixing a liquid pigment with an antistatic agent in an amount of 5 to 15% by weight, and injecting the liquid mixture into a molded product in an amount of 0.1 to 0.5% by weight. According to this, the bluing effect is exhibited most appropriately.

[0009]

FIG. 1 is a process chart showing the steps of an embodiment to which the resin production method according to the present invention is applied. This embodiment comprises a charging step 1, a mixing step 2, and an injection step 3. I have. In the charging step 1, a liquid antistatic agent and a blue-based liquid pigment stored in a container by a predetermined amount (for example, 18 liters) are prepared, and the liquid antistatic agent prepared in the charging step 1 is prepared. And the blue liquid pigment are mixed at a predetermined ratio in the next mixing step 2.

On the other hand, in the injection step 3, an injection molding machine 7 is provided. The injection molding machine 7 includes a predetermined resin molded product,
For example, a mold 4 composed of a fixed side 5 and a movable side 6 that can form a clothes storage container, and a resin injection section 9 for injecting resin into the mold 4 are provided. In addition, the resin injection section 9 is provided with a heating cylinder screw 10 and a hopper 8 for accommodating granular resin raw material supplied into the heating cylinder screw 10, and between the hopper 8 and the heating cylinder screw 10. A colorant injection mechanism 11 is provided. Colorant injection mechanism portion 11, the pre-Symbol mixture has a mechanism capable of supplying the heating cylinder screw 10 amounts to have in every shot that is set in advance.

In this embodiment having the above-described structure, the liquid antistatic agent containing 18 liters and the blue liquid pigment carried in the charging step 1 are mixed with the liquid antistatic agent in the mixing step 2. After being mixed at a rate of 10%, the mixture is injected into the heating cylinder screw 10 from the colorant injection mechanism 11 in a predetermined amount for each shot, and After being mixed with the resin to be melted in the above, the mixture is injected into the mold 4.

Therefore, after the mold 4 is cooled,
In the molded article to be taken out, since the antistatic agent is mixed together with the pigment, not only the antistatic effect can be obtained, but also the bluing effect by mixing the blue pigment can be obtained. In other words, by injecting the mixture containing the blue pigment from the colorant injection mechanism 11 in this way, a product having a bluing effect can be formed. There is no need to blend for incorporation or mixing.

The transparent resin molded product has a thickness of 1.5 mm to 3.0 mm depending on the size and application.
By adjusting the colorant injection mechanism 11 and changing the injection amount of the mixed liquid, it is possible to inject an appropriate amount of pigment so as to obtain a required bluing effect in the product. Therefore, the molding efficiency of the molded article having the bluing effect can be increased, and the manufacturing cost of the molded article can be reduced. In addition, in the liquid mixture, the liquid pigment is diluted 10-fold and injected into the product, so that the accuracy of measuring the injection amount is improved, and a very small amount of the pigment is evenly distributed throughout the product, and is uniformly distributed in each part of the product. A great bluing effect can be obtained.

Embodiment 1 Next, a more specific embodiment actually performed by the inventor will be described. In this example, a liquid pigment containing 97% by weight of a surfactant and 3% by weight of a pigment was used. The pigment is an inorganic ultramarine blue pigment. The liquid antistatic agent used was polyoxyethylene alkylamine. Then, in the mixing step 2, the antistatic agent and the liquid pigment were mixed by a pump at a ratio of 10: 1.

As the mold 4, a mold having a cavity capable of forming a 1.7 mm thick storage box used for storing clothing and the like is used. ) Using a Cisco Novo system, 0.3 wt% of the above mixed solution was injected into the product together with the PP raw material from the resin injection section 9. As a result, the product had a bluing effect in which the transparency was uniform in each part, and the antistatic effect was uniform throughout.

Embodiment 2 In Embodiment 2, the same liquid pigment and liquid antistatic agent and colorant injection mechanism 11 as in Embodiment 1 described above were used. The one having a cavity capable of forming a 2.7 mm storage box was used. Then, for each shot, 0.2% by weight of the mixture was injected into the product. As a result, the product had a bluing effect and an antistatic effect with uniform transparency. In other words, when the thickness of the product is thick as in Example 2, by lowering the blending ratio of the mixed solution to the product, the decrease in the transparency due to the excessive incorporation of the blue pigment is prevented, An appropriate bluing effect was obtained.
Therefore, it has been found that an appropriate bluing effect can be obtained by changing the injection amount of the mixture according to the thickness of the product without changing the mixing ratio of the mixture.

[0017]

As described above, the present invention provides a transparent resin
When molding a molded product, apply a blue liquid pigment every shot
Injection molding machine with a preset amount
Into the heating screw and melt in the heating screw.
After mixing with the resin to be melted, the mixture was injected into a mold . Therefore, when adding a bluing effect to a transparent resin molded product, it is not necessary to knead or blend a blue pigment prior to molding, and according to the wall thickness of the product, the amount of blue pigment per product It is also possible to freely change the content, and therefore, it is possible to simplify the process of performing bluing. In addition, pigments can be applied
Evenly spreads throughout the body, uniform bruin throughout the product
The effect can be obtained.

Further, since the amount of blue material mixed per product is uniform for each product, a product in which the blue pigment is excessively mixed and the transparency is impaired, or a product in which the blue pigment is mixed in too little is required. A product that does not provide a refreshing feeling of the product is not formed, an appropriate bluing effect is obtained for each product, and the product yield can be improved. In addition, the use of an inorganic ultramarine blue pigment as a pigment makes the bluing effect remarkable, and by injecting a liquid mixture of a liquid antistatic agent and a liquid pigment into a molded article, a very small amount can be obtained. The pigment of the formula is precisely and metered in, and is evenly distributed throughout the product.
A uniform bluing effect can be obtained for the entire product.

[Brief description of the drawings]

FIG. 1 is a process diagram showing a process of manufacturing a resin molded product having an antistatic effect according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Input process 2 Mixing process 3 Injection process 4 Die 7 Injection molding machine 9 Resin injection part 11 Colorant injection mechanism part

Claims (6)

(57) [Claims] 1. A blue-based liquid when molding a transparent resin molded article.
The amount of body pigment that is set in advance for each shot
Inject into the heating screw of the injection molding machine,
After mixing with the resin that melts in the heating screw, the mold
A bluing method for a transparent resin molded product, wherein the bluing is performed. 2. The method of claim 1, wherein the liquid pigment comprises 95 to 97% by weight of a surfactant and 3 to 5% by weight of a pigment. 3. The method for bluing a transparent resin molded product according to claim 2, wherein the pigment is an inorganic ultramarine blue pigment. 4. A mixed liquid is formed by mixing the liquid pigment with a liquid antistatic agent, and the mixed liquid is mixed in the heating screw.
2. A method for bluing a transparent resin molded product according to claim 1, wherein 5. The method for bluing a transparent resin molded product according to claim 4 , wherein the mixed liquid contains 5 to 15% by weight of a liquid pigment based on an antistatic agent. 6. The method of claim 5 the mixture according, brewing method of the transparent resin molded article characterized by injecting 0.1 to 0.5 wt% with respect to formed molded article.