Injection molding raw material composition for cosmetic containers having improved color reproducibility and functional properties, and method for manufacturing cosmetic container using the same

Abstract

The present invention relates to an injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality, and a method for manufacturing a cosmetic container using the same. An injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality according to one embodiment of the technical concept of the present invention comprises, for every 100 parts by weight of base resin, 1.8 to 9.5 parts by weight of a color influence control type functional masterbatch, 1.2 to 7.2 parts by weight of a color difference correction type color masterbatch, and 0.08 to 2.4 parts by weight of an interface-fixing type dispersion stabilizer, wherein the color influence control type functional masterbatch is configured in the form of pellets in which a surface-modified composite functional powder is dispersed within a carrier resin, and the color difference correction type color masterbatch is configured to correct deviations in CIE Lab* color values ​​caused by the addition of the color influence control type functional masterbatch. By the above configuration, the injection molding raw material composition for cosmetic containers according to the present invention includes both a color influence control type functional masterbatch and a color difference correction type color masterbatch, thereby correcting deviations in lightness value (L*), red-green axis color value (a*), and yellow-blue axis color value (b*) caused by the functional powder. Accordingly, color reproducibility for the target color is improved even in injection molded products containing the functional powder, and the color difference value ΔE relative to the reference color of the final injection molded product can be managed to be 2.5 or less.

Description

Technology Field

[0001] The present invention relates to an injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality, and a method for manufacturing cosmetic containers using the same. More specifically, the invention relates to an injection molding raw material composition for manufacturing a container body, cap, one-touch cap, guide cap, lid, pad receiving container, dropper member, or injection molded part combined therewith of a cosmetic container. By applying a color influence control type functional masterbatch containing functional powder in a base resin together with a color difference correction type color masterbatch, the antibacterial properties, deodorizing properties, UV blocking properties, storage stability of contents, and color reproducibility of the cosmetic container after injection molding can be secured together. The invention relates to an injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality, and a method for manufacturing cosmetic containers using the same. Background Technology

[0003] Cosmetic containers are used as packaging materials that contain cosmetic contents and protect them from external contamination, oxygen, moisture, ultraviolet rays, and impact. These cosmetic containers serve as important factors in determining not only the storage stability of the contents but also the product's appearance design, color, gloss, texture, and brand identification. Accordingly, cosmetic containers are required to simultaneously provide protection of the contents, hygiene, ease of use, and appearance quality.

[0004] Generally, the container body, cap, lid, guide cap, one-touch cap, pad receiving container, and dropper component of a cosmetic container are manufactured by injection molding. As a base resin for injection molding, acrylonitrile-butadiene-styrene copolymer (ABS) may be used considering the appearance, colorability, and dimensional stability of the container body; polypropylene (PP) may be used for cap components requiring repeated opening and closing, fastening, and hinge returnability; and polyethylene terephthalate glycol (PETG) may be used for components requiring translucency or gloss.

[0005] Meanwhile, there has recently been an increasing demand to impart functionalities to cosmetic containers—such as antibacterial, deodorizing, UV protection, and storage stability—in addition to the simple function of holding contents. To this end, methods involving mixing inorganic functional powders, such as zinc oxide, zeolite, titanium dioxide, and silica, into injection molding raw materials are being considered. While these inorganic functional powders are useful in terms of antibacterial properties, UV protection, adsorption, or dispersion stability, if they are not uniformly dispersed within the base resin, they can cause particle aggregation, surface roughness, whitening, reduced gloss, and color staining.

[0006] In particular, since the color quality of the product's appearance is critical for cosmetic containers, the appearance quality deteriorates if a discrepancy arises between the target color and the actual color of the injection-molded product due to the addition of functional powders. White inorganic particles, such as zinc oxide and titanium dioxide, can increase the lightness value or decrease the saturation of the molded product, while porous inorganic particles, such as zeolites, can cause grayish-white turbidity or surface roughness. Furthermore, color deviations in the injection-molded product may repeatedly occur depending on the particle size, surface condition, refractive index, and dispersion state of the functional powder.

[0007] Conventionally, a method of simply mixing a color masterbatch with a base resin was primarily used to achieve the color of cosmetic containers. However, when functional powders are included, the inherent color, particle scattering properties, and non-uniform dispersion of the functional powders themselves affect color realization; consequently, it is difficult to reliably ensure color reproducibility for the target color using only a standard color masterbatch. Furthermore, directly adding functional powders in powder form can reduce dispersibility within the resin and increase surface defects and color deviations in the molded product.

[0008] Furthermore, in injection molding material compositions containing functional powders, compatibility with the type of base resin is also important. Since ABS, PP, and PETG differ in their resin structures and melt characteristics, applying the same functional powder or masterbatch uniformly may result in interfacial non-uniformity, layer separation, color staining, reduced gloss, or deterioration of mechanical properties. Therefore, it is necessary to appropriately match the base resin and carrier resin for cosmetic container parts with different required properties, such as the container body, cap, and translucent parts, and to simultaneously control the surface modification state of the functional powder and color correction conditions.

[0009] Accordingly, there is a need for a technology that goes beyond simply adding functional powder to injection molding raw materials; instead, it involves composing the functional powder into a surface-modified composite functional powder, manufacturing a functional masterbatch by dispersing it in a carrier resin identical to the base resin, and determining the formulation ratio of a color difference-correcting color masterbatch after quantitatively calculating the color deviation resulting from the addition of the functional masterbatch. Such technology is useful as an injection molding raw material composition and manufacturing method for simultaneously satisfying the functional expression and appearance color reproducibility of cosmetic containers. Prior art literature

[0011] Korean Registered Patent No. 10-1702087 (Registered January 25, 2017) Korean Registered Patent No. 10-2403888 (Registered May 26, 2022) Korean Registered Patent No. 10-2216835 (Registered February 10, 2021) The problem to be solved

[0012] The problem that the present invention aims to solve is to provide an injection molding raw material composition for cosmetic containers that includes a functional powder for imparting antibacterial, deodorizing, UV blocking, and contents storage stability, while also being capable of quantitatively correcting color deviations caused by the inherent color, particle refractive index, and dispersion state of the functional powder.

[0013] In addition, the problem that the present invention aims to solve is to provide an injection molding raw material composition for cosmetic containers that can suppress aggregation, whitening, flow marks, gloss reduction, and surface roughness of functional powder in injection molded products by surface modifying a composite functional powder comprising silica-coated zinc oxide, alkylsilane-modified zeolite, alumina-silica composite-coated rutile-type titanium dioxide, and spherical silica spacers, and manufacturing a color-influence-controlled functional masterbatch by dispersing the same in a carrier resin of the same system as the base resin.

[0014] In addition, the problem that the present invention aims to solve is to provide a method for manufacturing a cosmetic container that can manage the color difference value ΔE relative to the reference color of the final injection molded product within a certain range by measuring the CIE Lab* color value of a functional reference specimen, calculating ΔL*, Δa*, Δb*, and ΔE with respect to a target color specimen, and then setting the combination and input amount of the correction pigment of the color difference correction type color masterbatch.

[0015] The various problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0017] In one embodiment of the technical concept of the present invention, an injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality is disclosed.

[0018] The above injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality comprises, for every 100 parts by weight of base resin, 1.8 to 9.5 parts by weight of a color influence control type functional masterbatch, 1.2 to 7.2 parts by weight of a color difference correction type color masterbatch, and 0.08 to 2.4 parts by weight of an interface-fixing type dispersion stabilizer, wherein the color influence control type functional masterbatch is configured in the form of pellets in which a surface-modified composite functional powder is dispersed within a carrier resin, and the color difference correction type color masterbatch is configured to correct deviations in CIE Lab* color values ​​caused by the addition of the color influence control type functional masterbatch.

[0019] The above base resin is selected from acrylonitrile-butadiene-styrene copolymer (ABS), polypropylene (PP), and polyethylene terephthalate glycol (PETG), and the carrier resin of the color influence control type functional masterbatch and the color difference correction type color masterbatch may be composed of a resin of the same system as the above base resin.

[0020] The above color influence control type functional masterbatch may comprise 18 to 42 parts by weight of a surface-modified composite functional powder, 1.5 to 6.0 parts by weight of an interfacial dispersant for the masterbatch, and the remainder of a carrier resin, wherein the total of the surface-modified composite functional powder, the interfacial dispersant for the masterbatch, and the carrier resin is 100 parts by weight.

[0021] The above surface-modified composite functional powder may include silica-coated zinc oxide, alkylsilane-modified zeolite, alumina-silica composite-coated rutile-type titanium dioxide, and spherical silica spacers.

[0022] The above surface-modified composite functional powder can be formed by sequentially performing a first silane treatment and a second wax treatment on the composite functional powder prior to surface modification.

[0023] The above 100 parts by weight of the composite functional powder before surface modification may include 26 to 36 parts by weight of silica-coated zinc oxide, 24 to 34 parts by weight of alkylsilane-modified zeolite, 20 to 30 parts by weight of alumina-silica composite-coated rutile-type titanium dioxide, and 8 to 16 parts by weight of spherical silica spacers.

[0024] The above first silane treatment can be performed using 0.35 to 1.25 parts by weight of a silane-based coupling agent per 100 parts by weight of the composite functional powder before surface modification.

[0025] The above secondary wax treatment can be performed using 0.45 to 1.80 parts by weight of polyethylene oxide wax per 100 parts by weight of composite functional powder before surface modification.

[0026] The average particle size D50 of the surface-modified composite functional powder may be 0.3 to 2.8 μm.

[0027] The color difference correction type color masterbatch described above comprises 10 to 36 parts by weight of a composite correction pigment, 1 to 6 parts by weight of a dispersant for the color masterbatch, and the remainder of a carrier resin, wherein the total of the composite correction pigment, the dispersant for the color masterbatch, and the carrier resin may be configured to be 100 parts by weight.

[0028] The above 100 parts by weight of the composite correction pigment may include 35 to 68 parts by weight of white correction pigment, 8 to 24 parts by weight of yellow correction pigment, 3 to 14 parts by weight of red correction pigment, 0.5 to 7 parts by weight of blue correction pigment, and 0.2 to 5 parts by weight of black correction pigment.

[0029] The above interface-fixed dispersion stabilizer comprises 30 to 65 parts by weight of polyethylene oxide wax and 35 to 70 parts by weight of maleic anhydride graft resin, wherein the total of the polyethylene oxide wax and maleic anhydride graft resin may be 100 parts by weight.

[0030] The above injection molding raw material composition comprises: an ABS-based container body composition comprising, per 100 parts by weight of ABS, 2.0 to 7.5 parts by weight of an ABS-based color influence control type functional masterbatch, 1.5 to 5.5 parts by weight of an ABS-based color difference correction type color masterbatch, and 0.10 to 1.8 parts by weight of an interface-fixing type dispersion stabilizer; and a PP-based cap part composition comprising, per 100 parts by weight of PP, 2.5 to 8.5 parts by weight of a PP-based color influence control type functional masterbatch, 2.8 to 6.8 parts by weight of a PP-based color difference correction type color masterbatch, 0.12 to 2.0 parts by weight of an interface-fixing type dispersion stabilizer, and 3.5 to 6.5 parts by weight of a polyolefin elastomer. It may be composed of any one of the following: a PETG-based translucent component composition comprising, for every 100 parts by weight of PETG, 1.8 to 4.8 parts by weight of a PETG-based color influence control type functional masterbatch, 1.2 to 3.8 parts by weight of a PETG-based color difference correction type color masterbatch, and 0.08 to 1.2 parts by weight of an interface-fixing type dispersion stabilizer.

[0031] In addition, another embodiment of the technical concept of the present invention discloses a method for manufacturing a cosmetic container with improved color reproducibility and functionality.

[0032] The above method for manufacturing a cosmetic container with improved color reproducibility and functionality comprises: a resin selection and drying step (S100) in which a base resin of ABS, PP, or PETG is selected and dried according to the part to be manufactured; a powder surface modification step (S200) in which a surface-modified composite functional powder is manufactured by sequentially performing a first silane treatment and a second wax treatment on a composite functional powder comprising silica-coated zinc oxide, alkylsilane-modified zeolite, alumina-silica composite-coated rutile-type titanium dioxide, and spherical silica spacers; and a functional masterbatch manufacturing step (S300) in which a color-influence-controlled functional masterbatch is manufactured by melt-kneading the surface-modified composite functional powder with a carrier resin and an interfacial dispersant for the masterbatch. A color difference calculation step (S400) for measuring the lightness value (L*), red-green axis color value (a*), and yellow-blue axis color value (b*) of a functional reference specimen including the base resin and the color influence control type functional masterbatch, and calculating ΔL*, Δa*, Δb*, and color difference value ΔE relative to a target color specimen; a correction masterbatch setting step (S500) for setting the correction pigment combination and input amount of the color difference correction type color masterbatch according to the ΔL*, Δa*, Δb*, and ΔE calculated in the color difference calculation step (S400); a raw material mixing step (S600) for manufacturing an injection molding raw material by mixing the base resin, the color influence control type functional masterbatch, the color difference correction type color masterbatch, and an interface-fixing dispersion stabilizer; and a pelletizing step (S700) for manufacturing injection molding pellets by melt-kneading and cutting the injection molding raw material. The method includes an injection step (S800) for manufacturing a cosmetic container by injection molding the above injection pellets; and an inspection step (S900) for inspecting the color reproducibility, appearance quality, and functionality of the cosmetic container.

[0033] The above color difference value ΔE is ΔE=[(ΔL*) 2 + (Δa*) 2+ (Δb*) 2 ] 1 / 2 It is calculated by, and the correction masterbatch setting step (S500) may be a step of setting the correction pigment combination or input amount of the color difference correction type color masterbatch so that the color difference value ΔE relative to the reference color of the final injection molded product is 2.5 or less.

[0034] Specific details of other embodiments are included in the detailed description. Effects of the invention

[0036] The injection molding raw material composition for cosmetic containers according to the present invention includes both a color influence control type functional masterbatch and a color difference correction type color masterbatch, so that deviations in lightness value (L*), red-green axis color value (a*), and yellow-blue axis color value (b*) caused by the functional powder can be corrected. Accordingly, color reproducibility for the target color is improved even in injection molded products containing the functional powder, and the color difference value ΔE relative to the reference color of the final injection molded product can be managed to be 2.5 or less.

[0037] In addition, the present invention uses a composite functional powder comprising silica-coated zinc oxide, alkylsilane-modified zeolite, alumina-silica composite-coated rutile-type titanium dioxide, and spherical silica spacers, and performs a primary silane treatment and a secondary wax treatment on the entire composite functional powder, thereby improving the interfacial affinity and dispersion stability of inorganic functional particles. Accordingly, whitening, pigment clumping, re-aggregation of functional powder, flow marks, gloss reduction, and surface roughness of injection-molded products can be suppressed.

[0038] In addition, the present invention separately applies an ABS-based composition for the container body, a PP-based composition for the cap part, and a PETG-based composition for the translucent part, and applies a carrier resin of the same system as each base resin and a maleic anhydride graft resin, thereby ensuring moldability, interfacial stability, and appearance quality corresponding to the resin characteristics of each part. In particular, by applying a polyolefin elastomer to the PP-based cap part, a cosmetic container with improved repeatability, hinge recovery, fastening feel, and shock absorption can be manufactured.

[0039] It will be fully understood that embodiments of the technical concept of the present invention may provide various effects not specifically mentioned. Brief explanation of the drawing

[0041] FIG. 1 is a flowchart illustrating a method for manufacturing a cosmetic container using an injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality according to one embodiment of the technical concept of the present invention. Specific details for implementing the invention

[0042] The advantages and features of the present invention, and the methods for achieving them, will become clear by referring to the embodiments described in detail below. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosed content is thorough and complete, and to ensure that the spirit of the present invention is sufficiently conveyed to those skilled in the art.

[0043] The terms used in this application are used merely to describe specific embodiments and are not intended to limit the invention. The singular expression includes the plural expression unless the context clearly indicates otherwise.

[0044] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application.

[0046] Hereinafter, a preferred embodiment of an injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality according to one embodiment of the technical concept of the present invention will be described in detail.

[0048] The present invention is characterized by the technical feature of controlling the surface state, dispersion state, and mixing ratio of color correction components of a functional powder in conjunction within an injection molding raw material composition for cosmetic containers, thereby ensuring the functionality, appearance uniformity, and color reproducibility of the cosmetic container after injection molding.

[0049] The present invention relates to an injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality, and a method for manufacturing cosmetic containers using the same. More specifically, the present invention relates to an injection molding raw material composition for manufacturing a container body, cap, one-touch cap, guide cap, lid, pad receiving container, dropper member, or injection molded part combined therewith of a cosmetic container, comprising a base resin, a color influence control type functional masterbatch, a color difference correction type color masterbatch, and an interface-fixing type dispersion stabilizer.

[0050] The injection molding raw material composition for cosmetic containers according to the present invention has a configuration that quantitatively calculates a color change value generated by the input of a functional powder and sets the mixing ratio of a color difference correction type color masterbatch based on the calculated color change value. Specifically, the present invention prepares a color influence control type functional masterbatch by surface-modifying a functional powder and dispersing it in a carrier resin, measures the CIE Lab* color value of a functional reference specimen into which the color influence control type functional masterbatch is input into a base resin, and sets the combination of correction pigments and the input amount of the color difference correction type color masterbatch according to the difference between the measured value and the target color value.

[0051] In the present invention, "color reproducibility" refers to the characteristic that, when cosmetic containers having the same target color are repeatedly injection molded, the external color of an injection-molded product remains within a certain range from the reference color or target color, even with differences in the input of functional powder, the type of base resin, the thickness of the molded product, the injection temperature, and mold conditions. The color reproducibility is evaluated based on CIE Lab* color values, and the color difference value ΔE relative to the reference color of the final injection-molded product is maintained at 2.5 or less. Preferably, the color difference value ΔE is 2.0 or less, and more preferably 1.5 or less. Here, the color difference value ΔE is ΔE=[(ΔL*) 2 + (Δa*) 2 + (Δb*) 2 ] 1 / 2 It is produced by.

[0052] In the present invention, "functionality" refers to a property that improves the hygiene, storage stability, protection, and deodorizing properties of a cosmetic container, along with the realization of the exterior color of the cosmetic container. The above functionality includes antibacterial properties, deodorizing properties, UV blocking properties, and storage stability of the contents.

[0054] The injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality according to the present invention comprises, with respect to 100 parts by weight of base resin, 1.8 to 9.5 parts by weight of a color influence control type functional masterbatch, 1.2 to 7.2 parts by weight of a color difference correction type color masterbatch, and 0.08 to 2.4 parts by weight of an interface-fixing type dispersion stabilizer.

[0056] The above base resin, color influence control type functional masterbatch, color difference correction type color masterbatch, and interface-fixing dispersion stabilizer are interconnected to simultaneously achieve interface stabilization of the functional powder, correction of color deviation, appearance uniformity during repeated injection, and the expression of functionality of the cosmetic container.

[0058] If the above-mentioned color-influence-controlling functional masterbatch is included in an amount of less than 1.8 parts by weight per 100 parts by weight of base resin, the expression of antibacterial, deodorizing, or UV blocking properties is reduced. Conversely, if the above-mentioned color-influence-controlling functional masterbatch is included in an amount exceeding 9.5 parts by weight, the color correction limit is exceeded due to the inherent color, particle refractive index, and dispersion state of the functional powder, or whitening, reduced gloss, flow marks, or surface roughness of the injection-molded product increases.

[0060] If the above color difference correction type color masterbatch is included in an amount of less than 1.2 parts by weight per 100 parts by weight of base resin, the deviations in lightness value (L*), red-green axis color value (a*), and yellow-blue axis color value (b*) caused by the color influence control type functional masterbatch are not sufficiently corrected. Conversely, if the above color difference correction type color masterbatch is included in an amount exceeding 7.2 parts by weight, the pigment concentration becomes excessive, leading to pigment aggregation, weld line emphasis, reduced gloss, or reduced mechanical properties.

[0062] If the above interface-fixing dispersion stabilizer is included in an amount of less than 0.08 parts by weight per 100 parts by weight of base resin, the interfacial stabilization between the functional powder and the color correction pigment is insufficient, resulting in color stains, pigment clumping, or re-aggregation of the functional powder. Conversely, if the above interface-fixing dispersion stabilizer is included in an amount exceeding 2.4 parts by weight, bleeding, uneven gloss, or surface contamination occurs on the surface of the injection-molded product.

[0064] The above base resin is classified and applied as a first base resin for the container body, a second base resin for the cap component, and a third base resin for the translucent component, depending on the type of component of the cosmetic container to be manufactured.

[0065] The first base resin above is a resin for ensuring the appearance gloss, colorability, dimensional stability, and impact resistance of the container body, and is composed of an acrylonitrile-butadiene-styrene copolymer (ABS).

[0066] The above second base resin is a resin for ensuring the repeated opening and closing, hinge restoring ability, and fastening ability of a cap, one-touch cap, guide cap, or lid, and is made of polypropylene (PP).

[0067] The above third base resin is a resin for ensuring transparency, surface gloss, and content visibility of container parts requiring a translucent or glossy appearance, and is composed of polyethylene terephthalate glycol (PETG).

[0069] The above-mentioned color-influence-controlling functional masterbatch is configured to impart antibacterial, deodorizing, UV-blocking, and contents storage stability to cosmetic containers. The above-mentioned color-influence-controlling functional masterbatch comprises a carrier resin, a surface-modified composite functional powder, and an interface dispersant for the masterbatch.

[0070] The above-described color influence-controlling functional masterbatch is provided in the form of pellets in which a surface-modified composite functional powder is dispersed within a carrier resin. Accordingly, local aggregation of the functional powder is suppressed, and color changes caused by the inherent color of the functional powder and the particle dispersion state are quantitatively corrected in a subsequent color difference correction step.

[0072] The above carrier resin is composed of a resin of the same system as the base resin of the final injection-molded product. An ABS-based carrier resin is used for the color-influence control functional masterbatch for ABS-based container bodies, a PP-based carrier resin is used for the color-influence control functional masterbatch for PP-based cap parts, and a PETG-based carrier resin is used for the color-influence control functional masterbatch for PETG-based translucent parts. By composing the carrier resin of the same system as the final base resin in this way, interfacial non-uniformity, layer separation, interfacial whitening, color staining, and injection surface defects between the color-influence control functional masterbatch and the base resin are suppressed.

[0074] The above color influence control type functional masterbatch comprises 18 to 42 parts by weight of a surface-modified composite functional powder, 1.5 to 6.0 parts by weight of an interfacial dispersant for the masterbatch, and the remainder of a carrier resin, wherein the total of the surface-modified composite functional powder, the interfacial dispersant for the masterbatch, and the carrier resin is 100 parts by weight.

[0075] If the above surface-modified composite functional powder is included in an amount of less than 18 parts by weight, the antibacterial, deodorizing, or UV blocking properties of the final injection-molded product are reduced. Conversely, if the above surface-modified composite functional powder is included in an amount exceeding 42 parts by weight, powder aggregation, increased extrusion torque, roughening of the pellet surface, and increased color deviation occur during masterbatch manufacturing.

[0076] The above-mentioned interfacial dispersant for the masterbatch is a component that disperses the surface-modified composite functional powder within the carrier resin. The above-mentioned interfacial dispersant for the masterbatch comprises one or more selected from ethylene bis stearamide (EBS), zinc stearate, calcium stearate, and polyethylene wax. Preferably, the above-mentioned interfacial dispersant for the masterbatch comprises both ethylene bis stearamide and zinc stearate. The ethylene bis stearamide improves the wettability of the composite functional powder during melt mixing, and the zinc stearate suppresses local aggregation of the inorganic powder to homogenize the powder distribution within the pellet.

[0078] The above surface-modified composite functional powder includes silica-coated zinc oxide, alkylsilane-modified zeolite, alumina-silica composite-coated rutile-type titanium dioxide, and spherical silica spacers.

[0079] The above silica-coated zinc oxide is a particle in which a silica coating layer is formed on the surface of a zinc oxide particle, and is a component that imparts antibacterial and UV blocking properties. The silica coating layer is a layer that reduces direct exposure of the zinc oxide particles, suppresses aggregation between zinc oxide particles, and improves dispersion stability within a carrier resin. The above silica-coated zinc oxide may be composed of particles in which a silica layer is formed on the surface of the zinc oxide by contacting zinc oxide powder with a silica precursor comprising sodium silicate, tetraethyl orthosilicate, or colloidal silica. The silica coating layer may be formed in an amount of 1 to 12 parts by weight per 100 parts by weight of zinc oxide.

[0080] The above alkylsilane-modified zeolite is a particle in which an alkylsilane-based organic group is introduced to the surface of the zeolite particle, and is a component that adsorbs odor components or volatile components through a porous adsorption structure. The above alkylsilane-modified zeolite may be composed of a zeolite in which a silane compound having an alkyl group having 8 to 18 carbon atoms is introduced to the surface of the zeolite. Specifically, the above alkylsilane-modified zeolite may be a zeolite surface-modified with one or more alkylsilane compounds selected from octyltrimethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane, and octadecyltrimethoxysilane. The above alkylsilane compound may be used in an amount of 0.5 to 5.0 parts by weight per 100 parts by weight of the zeolite. Accordingly, the interfacial affinity with the resin is improved while maintaining the porous adsorption structure of the zeolite, and gray stains, particle aggregation, and surface roughness caused by the zeolite particles are suppressed.

[0081] The above alumina-silica composite coated rutile-type titanium dioxide is a particle in which a composite coating layer containing alumina and silica is formed on the surface of a rutile-type titanium dioxide particle, and is a component that imparts ultraviolet scattering properties and protection of contents. The above alumina-silica composite coating layer is a layer that mitigates the surface activity of the titanium dioxide particle, improves dispersion stability within the carrier resin, and mitigates the decrease in color saturation caused by excessive whitening of the titanium dioxide. The above alumina-silica composite coated rutile-type titanium dioxide may be composed of a particle in which an alumina-silica composite coating layer is formed on the surface by contacting a rutile-type titanium dioxide particle with an aluminum salt and a silica precursor. The above aluminum salt may be one or more selected from aluminum sulfate, aluminum nitrate, or sodium aluminate. The above silica precursor may be one or more selected from sodium silicate, tetraethyl orthosilicate, or colloidal silica. The above alumina-silica composite coating layer can be formed in an amount of 2 to 15 parts by weight per 100 parts by weight of rutile-type titanium dioxide.

[0082] The spherical silica spacer is a component that is interposed between inorganic functional particles as spherical or substantially spherical amorphous silica particles to suppress re-aggregation between particles and improve surface uniformity and gloss stability of injection-molded products. The spherical silica spacer may be precipitated silica, fused silica, or spherical silica produced by the sol-gel method. The spherical silica spacer may have an average particle size D50 of 0.3 to 2.5 μm, and maintains the inter-particle spacing within the composite functional powder to improve the dispersibility of the functional powder and suppress flow marks and roughness on the surface of the injection-molded product.

[0083] Here, the coating or modification of the silica-coated zinc oxide, alkylsilane-modified zeolite, and alumina-silica composite-coated rutile-type titanium dioxide refers to a pre-surface treatment formed in advance on the individual functional particles themselves. On the other hand, the first silane treatment and the second wax treatment of the powder surface modification step (S200) described later are post-treatments additionally performed on the entire composite functional powder formed by quantitatively mixing the individual functional particles. Therefore, the pre-surface treatment of the individual functional particles and the additional surface modification of the entire composite functional powder are distinguished from each other.

[0085] The above 100 parts by weight of the composite functional powder before surface modification comprises 26 to 36 parts by weight of silica-coated zinc oxide, 24 to 34 parts by weight of alkylsilane-modified zeolite, 20 to 30 parts by weight of alumina-silica composite-coated rutile-type titanium dioxide, and 8 to 16 parts by weight of spherical silica spacers, and is adjusted so that the total of each component is 100 parts by weight. The above surface-modified composite functional powder refers to a powder obtained by sequentially performing a first silane treatment and a second wax treatment on the above composite functional powder before surface modification.

[0086] If the above silica-coated zinc oxide is less than 26 parts by weight, the expression of antibacterial and UV blocking properties is reduced, and if it exceeds 36 parts by weight, the decrease in saturation of the target color due to increased whiteness increases. If the above alkylsilane-modified zeolite is less than 24 parts by weight, the adsorption of odor components and volatile components is reduced, and if it exceeds 34 parts by weight, an increase in grayish-white turbidity and a decrease in gloss occur. If the above alumina-silica composite-coated rutile-type titanium dioxide is less than 20 parts by weight, UV scattering properties and content protection properties are reduced, and if it exceeds 30 parts by weight, whitening and a decrease in color clarity occur. If the above spherical silica spacer is less than 8 parts by weight, the dispersion stabilization effect of the composite functional powder is reduced, and if it exceeds 16 parts by weight, surface roughness or a decrease in gloss of the injection-molded product occurs.

[0087] The above surface-modified composite functional powder is adjusted so that the average particle size D50 is 0.3 to 2.8 μm. If the average particle size D50 is less than 0.3 μm, the cohesive force between particles increases, resulting in reduced uniform dispersion within the color-influence-controlling functional masterbatch. Conversely, if the average particle size D50 exceeds 2.8 μm, fine protrusions, flow marks, or reduced gloss occur on the surface of the injection-molded product.

[0089] The surface-modified composite functional powder is a powder obtained by mixing the individual functional particles and then sequentially performing a first silane treatment and a second wax treatment on the entire composite functional powder. The first silane treatment is a treatment in which a silane-based coupling agent is brought into contact with the surface of the composite functional powder to react with or adsorb hydroxyl groups on the surface of inorganic particles, and the second wax treatment is a treatment in which polyethylene oxide wax is attached to or coated on the surface of the composite functional powder that has undergone the first silane treatment.

[0090] The above first silane treatment is intended to improve interfacial affinity between the composite functional powder and the carrier resin, and the above second wax treatment is intended to suppress inter-particle friction, re-aggregation, and increase in extrusion torque of the composite functional powder during melt mixing.

[0091] The above silane-based coupling agent may include one or more selected from 3-glycidoxypropyltrimethoxysilane, 3-aminopropyltriethoxysilane, vinyltrimethoxysilane, and 3-methacryloxypropyltrimethoxysilane. Preferably, 3-glycidoxypropyltrimethoxysilane or 3-aminopropyltriethoxysilane is used when applied to an ABS-based or PETG-based carrier resin, and vinyltrimethoxysilane or 3-methacryloxypropyltrimethoxysilane is used when applied to a PP-based carrier resin.

[0092] The above silane-based coupling agent is used in an amount of 0.35 to 1.25 parts by weight per 100 parts by weight of the composite functional powder before surface modification. If the above silane-based coupling agent is used in an amount less than 0.35 parts by weight, the interfacial affinity between the inorganic particles and the carrier resin decreases, and if it is used in an amount exceeding 1.25 parts by weight, gas generation or surface contamination increases during injection molding.

[0093] The above polyethylene oxide wax may be composed of polyethylene oxide wax having an acid value of 10 to 35 mgKOH / g and a softening point of 95 to 125℃. The above polyethylene oxide wax is used in an amount of 0.45 to 1.80 parts by weight per 100 parts by weight of the composite functional powder prior to surface modification. If the above polyethylene oxide wax is used in an amount less than 0.45 parts by weight, the effect of inhibiting particle re-aggregation during melt mixing is reduced, and if it is used in an amount exceeding 1.80 parts by weight, bleeding or uneven gloss occurs on the surface of the molded product.

[0095] The above color difference correction type color masterbatch is configured to correct color deviations caused by the addition of a color influence control type functional masterbatch and to achieve the target color of a cosmetic container. The above color difference correction type color masterbatch includes a carrier resin, a composite correction pigment, and a dispersant for the color masterbatch.

[0096] The carrier resin of the above color difference correction type color masterbatch is composed of a resin of the same system as the final base resin. An ABS-based color difference correction type color masterbatch is used for ABS-based parts, a PP-based color difference correction type color masterbatch is used for PP-based parts, and a PETG-based color difference correction type color masterbatch is used for PETG-based parts. By composing the carrier resin of the color difference correction type color masterbatch to be of the same system as the final base resin in this way, the dispersibility of the color correction pigment is improved, and color stains and surface defects caused by the incorporation of heterogeneous resins are suppressed.

[0097] The color difference correction type color masterbatch comprises 10 to 36 parts by weight of a composite correction pigment, 1 to 6 parts by weight of a dispersant for the color masterbatch, and the remainder of a carrier resin, wherein the total of the composite correction pigment, the dispersant for the color masterbatch, and the carrier resin is 100 parts by weight.

[0099] The above-mentioned dispersant for the color masterbatch may include one or more selected from polyethylene wax, ethylenebisstearamide, zinc stearate, and polymer pigment dispersant. The above-mentioned polymer pigment dispersant may be composed of a resin-type dispersant in which a dispersing functional group including a carboxyl group, a maleic anhydride group, or an amine group is introduced into a polyolefin-based main chain or a styrene-based main chain.

[0100] The above composite correction pigment includes all of the white correction pigment, yellow correction pigment, red correction pigment, blue correction pigment, and black correction pigment. The above composite correction pigment is a combination for correcting simultaneous changes in lightness value (L*), red-green axis color value (a*), and yellow-blue axis color value (b*) caused by the input of a color influence-controlling functional masterbatch.

[0101] The above 100 parts by weight of the composite correction pigment comprises 35 to 68 parts by weight of white correction pigment, 8 to 24 parts by weight of yellow correction pigment, 3 to 14 parts by weight of red correction pigment, 0.5 to 7 parts by weight of blue correction pigment, and 0.2 to 5 parts by weight of black correction pigment, and is adjusted so that the total of each component is 100 parts by weight.

[0102] The above white correction pigment includes rutile-type titanium dioxide. The above yellow correction pigment includes an iron oxide-based yellow pigment, and the above red correction pigment includes an iron oxide-based red pigment. The above blue correction pigment includes a phthalocyanine-based blue pigment, and the above black correction pigment includes a carbon black-based black pigment. Specifically, the above yellow correction pigment may include CI Pigment Yellow 42, the above red correction pigment may include CI Pigment Red 101, the above blue correction pigment may include CI Pigment Blue 15:3, and the above black correction pigment may include CI Pigment Black 7.

[0103] The above white correction pigment controls turbidity and lightness deviations caused by the functional powder. The above yellow correction pigment and red correction pigment correct the yellow axis and red axis of the target color. The above blue correction pigment corrects the blue axis deviation resulting from the increase in whiteness of the functional powder. The above black correction pigment corrects excessive lightness increase and saturation decrease.

[0105] The composition of the color difference correction type color masterbatch is determined by comparing the color value and the target color value after the addition of the color influence control type functional masterbatch. Specifically, a functional reference specimen is first prepared by mixing only the base resin and the color influence control type functional masterbatch, and the lightness value (L*), red-green axis color value (a*), and yellow-blue axis color value (b*) of the functional reference specimen are measured. Subsequently, ΔL*, Δa*, Δb*, and ΔE are calculated by comparing them with the lightness value (L*), red-green axis color value (a*), and yellow-blue axis color value (b*) of the target color specimen. The mixing ratios of the white correction pigment, yellow correction pigment, red correction pigment, blue correction pigment, and black correction pigment are adjusted according to the sign and magnitude of the calculated ΔL*, Δa*, and Δb*. The amount of the color difference correction type color masterbatch added to the final injection molded product is set so that the ΔE relative to the reference color is 2.5 or less.

[0106] The above color values ​​are measured using a colorimeter and under standard light source D65 and 10-degree observer conditions. The functional reference specimen and the target color specimen are manufactured as plate-shaped specimens having the same thickness and the same surface condition for measurement. Accordingly, the error in calculating color deviation due to differences in molded product thickness, surface roughness, or measurement conditions is reduced.

[0108] The above interface-fixing dispersion stabilizer is configured to improve interfacial affinity and dispersion stability between a base resin, a color influence control type functional masterbatch, and a color difference correction type color masterbatch. The above interface-fixing dispersion stabilizer comprises polyethylene oxide wax and maleic anhydride graft resin.

[0109] The above polyethylene oxide wax is a component that reduces inter-particle friction during melt mixing of functional powder and corrective pigment and improves the dispersibility of functional powder and corrective pigment within the resin. The above polyethylene oxide wax may be composed of polyethylene oxide wax having an acid value of 10 to 35 mgKOH / g and a softening point of 95 to 125℃.

[0110] The above maleic anhydride graft resin is a component that improves interfacial affinity between inorganic functional powder, corrective pigment, and base resin. The above maleic anhydride graft resin is selected according to the type of base resin. Specifically, maleic anhydride grafted polypropylene is applied to PP-based injection molding raw material compositions, maleic anhydride grafted styrene-based resin or maleic anhydride grafted ABS-based resin is applied to ABS-based injection molding raw material compositions, and maleic anhydride grafted polyester-based resin or maleic anhydride grafted acrylic-based resin having polyester compatibility may be applied to PETG-based injection molding raw material compositions.

[0111] The maleic anhydride graft resin may be a resin having a maleic anhydride graft rate of 0.3 to 3.0 weight%. If the maleic anhydride graft rate is less than 0.3 weight%, the effect of improving interfacial affinity between the inorganic functional powder and the base resin may be reduced, and if it exceeds 3.0 weight%, the fluidity of the resin may decrease, the surface hardness may change, or the surface defects of the injection molded product may increase.

[0113] The above-described interface-fixing dispersion stabilizer comprises 30 to 65 parts by weight of polyethylene oxide wax and 35 to 70 parts by weight of maleic anhydride graft resin, wherein the total of the polyethylene oxide wax and the maleic anhydride graft resin is 100 parts by weight. If the polyethylene oxide wax is less than 30 parts by weight, the effect of improving dispersibility during melt mixing is reduced, and if it exceeds 65 parts by weight, bleeding or non-uniform gloss occurs on the surface of the injection-molded product. If the maleic anhydride graft resin is less than 35 parts by weight, the interfacial affinity between the inorganic functional powder and the base resin is reduced, and if it exceeds 70 parts by weight, a decrease in resin fluidity or a change in surface hardness occurs.

[0115] The injection molding raw material composition of the present invention is classified into a first injection molding raw material composition, a second injection molding raw material composition, and a third injection molding raw material composition according to the parts of the cosmetic container.

[0116] The first injection molding raw material composition is a composition for an ABS-based container body. The first injection molding raw material composition comprises, with respect to 100 parts by weight of ABS, 2.0 to 7.5 parts by weight of an ABS-based color influence control type functional masterbatch, 1.5 to 5.5 parts by weight of an ABS-based color difference correction type color masterbatch, and 0.10 to 1.8 parts by weight of an interface-fixing type dispersion stabilizer. The first injection molding raw material composition is configured to simultaneously ensure the appearance gloss, color reproducibility, antibacterial properties, deodorizing properties, and storage stability of the contents of the container body.

[0118] The second injection molding raw material composition is a composition for PP-based caps, one-touch caps, guide caps, or lids. The second injection molding raw material composition comprises, with respect to 100 parts by weight of PP, 2.5 to 8.5 parts by weight of a PP-based color influence control type functional masterbatch, 2.8 to 6.8 parts by weight of a PP-based color difference correction type color masterbatch, 0.12 to 2.0 parts by weight of an interface-fixing type dispersion stabilizer, and 3.5 to 6.5 parts by weight of a polyolefin elastomer (POE).

[0119] The above polyolefin elastomer is a component that provides the repetitive opening and closing ability, hinge restorability, fastening feel, and shock absorption of the PP-based cap component. The above polyolefin elastomer may be an ethylene-α-olefin copolymer comprising ethylene and an α-olefin having 3 to 8 carbon atoms. The above α-olefin may be one or more selected from propylene, 1-butene, 1-hexene, and 1-octene.

[0120] The above polyolefin elastomer may have a density of 0.850 to 0.900 g / cm³ and a Melt Flow Index (MFI) of 0.5 to 20 g / 10 min under conditions of 190°C and 2.16 kg. Within the above density and melt flow index ranges, elastic recovery, injection fluidity, and fastening stability of the PP-based cap component are simultaneously ensured.

[0121] If the above polyolefin elastomer is included in an amount of less than 3.5 parts by weight per 100 parts by weight of PP, the elasticity and hinge recovery of the repeated opening and closing part are reduced, and if it is included in an amount exceeding 6.5 parts by weight, the dimensional stability, fastening strength, and surface hardness of the cap are reduced.

[0123] The third injection molding raw material composition is a PETG-based composition for translucent or glossy container parts. The third injection molding raw material composition comprises, with respect to 100 parts by weight of PETG, 1.8 to 4.8 parts by weight of a PETG-based color influence control type functional masterbatch, 1.2 to 3.8 parts by weight of a PETG-based color difference correction type color masterbatch, and 0.08 to 1.2 parts by weight of an interface-fixing type dispersion stabilizer. The third injection molding raw material composition is configured to ensure UV blocking properties and contents storage stability while maintaining translucency or glossiness.

[0124] A cosmetic container manufactured using the above injection molding raw material composition is formed as a single-layer injection molding structure. The single-layer injection molding structure is a structure in which a color influence-controlling functional component and a color difference-correcting color component are uniformly dispersed within the injection molding raw material composition. Accordingly, the functional component and the color correction component are distributed together in the thickness direction and the surface direction of the molded product, thereby maintaining the external color, surface quality, and functionality of the cosmetic container.

[0126] Hereinafter, with reference to the attached drawings, a method for manufacturing a cosmetic container using an injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality according to one embodiment of the technical concept of the present invention will be described in detail with preferred embodiments.

[0128] FIG. 1 is a flowchart illustrating a method for manufacturing a cosmetic container using an injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality according to one embodiment of the technical concept of the present invention.

[0130] Referring to FIG. 1, a method for manufacturing a cosmetic container using an injection molding raw material composition for a cosmetic container with improved color reproducibility and functionality according to one embodiment of the technical concept of the present invention comprises a resin selection and drying step (S100), a powder surface modification step (S200), a functional masterbatch manufacturing step (S300), a color difference calculation step (S400), a correction masterbatch setting step (S500), a raw material mixing step (S600), a pelletizing step (S700), an injection step (S800), and an inspection step (S900).

[0132] 1. Resin selection and drying step (S100)

[0133] The resin selection and drying step (S100) above is a step of selecting one of ABS, PP, or PETG as a base resin based on the type of part, required appearance, repetitive opening and closing properties, transparency, and molding shrinkage characteristics of the cosmetic container to be manufactured, and drying the selected base resin.

[0134] When manufacturing the container body, ABS is selected considering appearance gloss, colorability, dimensional stability, and impact resistance. When manufacturing caps, one-touch caps, guide caps, or lids, PP is selected considering repeatability, hinge returnability, and fastening properties. When manufacturing translucent or glossy container parts, PETG is selected considering transparency, surface gloss, and content visibility.

[0135] The above ABS is dried at 75 to 90°C for 2 to 4 hours. The above PP is dried at 60 to 80°C for 1 to 3 hours. The above PETG is dried at 65 to 80°C for 3 to 6 hours. The drying is intended to reduce residual moisture in the base resin to suppress bubbles, silver streaks, surface defects, and color non-uniformity that occur during melt mixing or injection molding. After drying, the base resin is stored in a sealed container or fed into a hopper that maintains a dry state and supplied to a subsequent mixing step.

[0137] 2. Powder surface modification step (S200)

[0138] The above powder surface modification step (S200) is a step of quantitatively mixing silica-coated zinc oxide, alkylsilane-modified zeolite, alumina-silica composite-coated rutile-type titanium dioxide, and spherical silica spacers, and sequentially performing a first silane treatment and a second wax treatment on the entire quantitatively mixed composite functional powder.

[0139] The above composite functional powder is prepared by quantitatively adding 26 to 36 parts by weight of silica-coated zinc oxide, 24 to 34 parts by weight of alkylsilane-modified zeolite, 20 to 30 parts by weight of alumina-silica composite-coated rutile-type titanium dioxide, and 8 to 16 parts by weight of spherical silica spacers. Each of the above components is adjusted so that the total is 100 parts by weight.

[0140] The above-mentioned quantitatively added powder is introduced into a dry mixer and pre-mixed for 5 to 30 minutes. Afterward, the pre-mixed composite functional powder is pre-dried at 85 to 115°C. The pre-drying is intended to reduce the adsorbed moisture on the surface of the inorganic powder to increase the surface reactivity of the silane coupling agent and to suppress the generation of moisture-derived bubbles or silver streaks during subsequent melt mixing.

[0141] A silane-based coupling agent is first added to the above-mentioned pre-dried composite functional powder. The silane-based coupling agent comprises one or more selected from 3-glycidoxypropyltrimethoxysilane, 3-aminopropyltriethoxysilane, vinyltrimethoxysilane, and 3-methacryloxypropyltrimethoxysilane. The silane-based coupling agent is used in an amount of 0.35 to 1.25 parts by weight per 100 parts by weight of the composite functional powder prior to surface modification.

[0142] The above silane-based coupling agent may be sprayed in a diluted state in ethanol, isopropanol, or a mixed solvent thereof. The composite functional powder sprayed with the above silane-based coupling agent is mixed at 60 to 100°C for 10 to 60 minutes to undergo a primary silane treatment. The above primary silane treatment is a treatment that improves the interfacial affinity between the composite functional powder and the carrier resin by causing the hydroxyl groups on the surface of the inorganic particles to react with or be adsorbed by the silane-based coupling agent.

[0143] Polyethylene oxide wax is secondarily added to the above primary silane-treated composite functional powder. The above polyethylene oxide wax may consist of polyethylene oxide wax having an acid value of 10 to 35 mgKOH / g and a softening point of 95 to 125℃. The above polyethylene oxide wax is used in an amount of 0.45 to 1.80 parts by weight per 100 parts by weight of the composite functional powder before surface modification.

[0144] The above polyethylene oxide wax can be introduced in a heated molten state or in a powder state, and is mixed at 90 to 130°C for 10 to 40 minutes to undergo a secondary wax treatment. The secondary wax treatment is a treatment that imparts lubricity and dispersibility to the surface of the composite functional powder, thereby suppressing inter-particle friction, re-aggregation, and an increase in extrusion torque during subsequent masterbatch manufacturing.

[0145] The above two-stage surface-modified composite functional powder is cooled and then subjected to a sieving or crushing process to adjust the average particle size D50 to 0.3 to 2.8 μm. By adjusting the average particle size D50 to the above range, the dispersibility, surface smoothness, and color correction properties of the functional powder are ensured.

[0147] 3. Functional masterbatch manufacturing step (S300)

[0148] The above functional masterbatch manufacturing step (S300) is a step of melt-kneading the above 2-step surface-modified composite functional powder together with a carrier resin and an interfacial dispersant for the masterbatch, and cooling and cutting the extruded product to manufacture a color-influence-controlled functional masterbatch in the form of pellets.

[0149] The above color influence control type functional masterbatch comprises 18 to 42 parts by weight of a surface-modifying composite functional powder, 1.5 to 6.0 parts by weight of an interfacial dispersant for the masterbatch, and the remainder of a carrier resin, wherein the total of each component is 100 parts by weight.

[0150] The above carrier resin is applied as a resin of the same system as the base resin of the part to be manufactured. When manufacturing a functional masterbatch for an ABS-based container body, an ABS-based carrier resin is used; when manufacturing a functional masterbatch for a PP-based cap part, a PP-based carrier resin is used; and when manufacturing a functional masterbatch for a PETG-based translucent part, a PETG-based carrier resin is used.

[0151] The above-mentioned interfacial dispersant for the masterbatch comprises one or more selected from ethylenebisstearamide, zinc stearate, calcium stearate, and polyethylene wax. Preferably, the above-mentioned interfacial dispersant for the masterbatch comprises ethylenebisstearamide and zinc stearate together.

[0152] The above carrier resin, surface-modified composite functional powder, and interface dispersant for the masterbatch are pre-mixed and then fed into a twin-screw extruder. At this time, the surface-modified composite functional powder may be fed in a lump sum, or divided and fed into a main feed section and a side feed section to suppress powder aggregation.

[0153] The above melt mixing is performed at different temperatures depending on the type of carrier resin. When using an ABS-based carrier resin, melt mixing is performed at 185 to 225°C; when using a PP-based carrier resin, melt mixing is performed at 175 to 215°C; and when using a PETG-based carrier resin, melt mixing is performed at 210 to 245°C.

[0154] The strand discharged after the above melt mixing is cooled through cooling water or an air cooling device, and then cut to be manufactured into a pellet form. The average length of the pellets of the color influence-controlled functional masterbatch is adjusted to 2 to 4 mm. If the average length of the pellets is less than 2 mm, the generation of fine particles increases during subsequent mixing, and if it exceeds 4 mm, the uniformity of dry mixing with the base resin may decrease.

[0156] 4. Color difference calculation step (S400)

[0157] The above color difference calculation step (S400) is a step of preparing a functional reference specimen by mixing only the base resin and the color influence control type functional masterbatch, and measuring the color value of the functional reference specimen to calculate the color deviation caused by the functional powder.

[0158] The above functional reference specimen is prepared by mixing 1.8 to 9.5 parts by weight of a color influence control type functional masterbatch with 100 parts by weight of a base resin. At this time, a color difference correction type color masterbatch is not added to the functional reference specimen. Accordingly, the functional reference specimen is used as a reference specimen to verify the effect of the functional powder itself on the color of the base resin.

[0159] The above functional reference specimen is formed into a plate-shaped specimen having the same thickness and the same surface condition as the target color specimen. The thickness of the plate-shaped specimen can be set to correspond to the representative thickness of the cosmetic container to be manufactured at the end, and can be set in the range of 1.0 to 3.0 mm.

[0160] The lightness value (L*), red-green axis color value (a*), and yellow-blue axis color value (b*) of the above functional reference specimen are measured using a colorimeter. These color values ​​are measured under standard light source D65 and 10-degree observer conditions. Subsequently, ΔL*, Δa*, Δb*, and ΔE are calculated by comparing them with the lightness value (L*), red-green axis color value (a*), and yellow-blue axis color value (b*) of the target color specimen. The above ΔE is calculated as ΔE=[(ΔL*) 2 + (Δa*) 2 + (Δb*) 2 ] 1 / 2 It is produced by.

[0161] The above step quantifies the increase in brightness, decrease in saturation, shift in the yellow axis, shift in the blue axis, or increase in grayish-white turbidity caused by the input of the functional powder, and provides a reference value for the subsequent correction masterbatch setting step (S500).

[0163] 5. Calibration Masterbatch Setup Step (S500)

[0164] The correction masterbatch setting step (S500) is a step of determining the combination of correction pigments and the amount of input for the color difference correction type color masterbatch according to ΔL*, Δa*, Δb* and ΔE calculated in the color difference calculation step (S400).

[0165] In the above step, the lightness deviation, red-green deviation, and yellow-blue deviation between the target color specimen and the functional reference specimen are analyzed, respectively. Based on the signs and magnitudes of the calculated ΔL*, Δa*, and Δb*, the mixing ratios of the white correction pigment, yellow correction pigment, red correction pigment, blue correction pigment, and black correction pigment are adjusted.

[0166] The above white correction pigment includes rutile-type titanium dioxide, the above yellow correction pigment includes an iron oxide-based yellow pigment, and the above red correction pigment includes an iron oxide-based red pigment. The above blue correction pigment includes a phthalocyanine-based blue pigment, and the above black correction pigment includes a carbon black-based black pigment. Specifically, the above yellow correction pigment may include CI Pigment Yellow 42, the above red correction pigment may include CI Pigment Red 101, the above blue correction pigment may include CI Pigment Blue 15:3, and the above black correction pigment may include CI Pigment Black 7.

[0167] The color difference correction type color masterbatch comprises 10 to 36 parts by weight of a composite correction pigment, 1 to 6 parts by weight of a dispersant for the color masterbatch, and the remainder of a carrier resin, wherein the total of each component is 100 parts by weight. The dispersant for the color masterbatch may include one or more selected from polyethylene wax, ethylenebisstearamide, zinc stearate, and polymer pigment dispersants.

[0168] The amount of the color difference correction type color masterbatch is set so that the ΔE relative to the reference color of the final injection-molded product is 2.5 or less. To this end, a correction specimen prepared with a first correction mixing ratio is molded, and if the ΔE of the correction specimen exceeds 2.5, the mixing ratio of the composite correction pigment or the amount of the color difference correction type color masterbatch can be readjusted. Accordingly, the color deviation relative to the target color is quantitatively corrected even in injection-molded products containing functional powder.

[0170] 6. Raw material mixing step (S600)

[0171] The above raw material mixing step (S600) is a step of mixing a base resin, a color influence control type functional masterbatch, a color difference correction type color masterbatch, and an interface-fixing type dispersion stabilizer according to the composition ratio of each part.

[0172] The raw material for the ABS-based container body is prepared by mixing 2.0 to 7.5 parts by weight of an ABS-based color influence control type functional masterbatch, 1.5 to 5.5 parts by weight of an ABS-based color difference correction type color masterbatch, and 0.10 to 1.8 parts by weight of an interface-fixing type dispersion stabilizer, based on 100 parts by weight of ABS.

[0173] The raw material for PP-based cap parts is prepared by mixing 2.5 to 8.5 parts by weight of a PP-based color influence control type functional masterbatch, 2.8 to 6.8 parts by weight of a PP-based color difference correction type color masterbatch, 0.12 to 2.0 parts by weight of an interface-fixing type dispersion stabilizer, and 3.5 to 6.5 parts by weight of a polyolefin elastomer, based on 100 parts by weight of PP.

[0174] The raw material for PETG-based translucent parts is prepared by mixing 1.8 to 4.8 parts by weight of a PETG-based color influence control type functional masterbatch, 1.2 to 3.8 parts by weight of a PETG-based color difference correction type color masterbatch, and 0.08 to 1.2 parts by weight of an interface-fixing type dispersion stabilizer, based on 100 parts by weight of PETG.

[0175] The above raw material mixing can be performed for 5 to 20 minutes using a tumble mixer, a ribbon mixer, or a high-speed mixer. During the mixing process, the mixing time is adjusted so that the color influence control type functional masterbatch and the color difference correction type color masterbatch are uniformly distributed in the base resin. If the mixing time is excessively short, uneven distribution of the masterbatch occurs, and if it is excessively long, pellet surface wear or fine powder generation may increase.

[0177] 7. Pelletization step (S700)

[0178] The above pelletizing step (S700) is a step of melting and kneading the injection raw materials for each part produced in the above raw material mixing step (S600) under low shear conditions, and cooling and cutting the extruded material to produce injection pellets.

[0179] In the present invention, low-shear melt mixing refers to mixing conditions performed by controlling the screw rotation speed of a twin-screw extruder to a range of 80 to 180 rpm and adjusting the residence time of the molten resin to a range of 30 to 120 seconds in order to suppress damage to the surface modification layer of the composite functional powder and thermal discoloration of the color correction pigment.

[0180] The above melt mixing is performed differently depending on the type of base resin. ABS-based compositions are mixed at 185 to 230°C. PP-based compositions are mixed at 175 to 220°C. PETG-based compositions are mixed at 215 to 250°C.

[0181] The injection molding materials for each of the above parts are fed into the main feed section of the twin-screw extruder, and, if necessary, the interface-fixing dispersion stabilizer or a portion of the masterbatch may be divided and fed into the side feed section. This divided feeding is intended to reduce the time during which the functional powder or corrective pigment in the masterbatch is subjected to excessive shear, thereby suppressing damage to the surface modification layer and thermal discoloration of the pigment.

[0182] If the melt mixing temperature is lower than the above range, the dispersibility of the color influence control type functional masterbatch and the color difference correction type color masterbatch is reduced, and if it is higher than the above range, damage to the surface modification layer of the functional powder, pigment discoloration, or resin degradation occurs. In addition, if the screw rotation speed is lower than the above range, dispersion uniformity is reduced, and if it is higher than the above range, damage to the surface modification layer of the inorganic functional powder or pigment thermal discoloration increases.

[0183] After the above low-shear melt mixing, the extruded product is discharged in the form of a strand, cooled by cooling water or air cooling, and then cut to produce injection pellets. The injection pellets may be cut to an average length of 2 to 4 mm to ensure supply stability in the subsequent injection step (S800).

[0185] 8. Injection step (S800)

[0186] The injection step (S800) above is a step of feeding the injection pellets into an injection molding machine and injecting molten resin into a mold corresponding to the shape of a cosmetic container to form a container body, a cap, a one-touch cap, a guide cap, a lid, a pad receiving container, or a dropper member.

[0187] The above injection pellets may be re-dried as needed before being fed into the injection molding machine hopper. ABS-based injection pellets may be re-dried at 75 to 90°C for 1 to 3 hours, and PETG-based injection pellets may be re-dried at 65 to 80°C for 2 to 5 hours. PP-based injection pellets may be omitted from re-drying if moisture adsorption during storage is not significant, but may be re-dried at 60 to 80°C for 1 to 2 hours if surface moisture is present.

[0188] The above injection molding is performed by controlling the cylinder temperature, mold temperature, injection pressure, holding pressure, cooling time, and injection speed according to the type of base resin. ABS-based compositions can be molded at a cylinder temperature of 190 to 240°C and a mold temperature of 40 to 70°C. PP-based compositions can be molded at a cylinder temperature of 180 to 230°C and a mold temperature of 25 to 55°C. PETG-based compositions can be molded at a cylinder temperature of 220 to 260°C and a mold temperature of 25 to 60°C.

[0189] In the injection step (S800) above, injection speed and holding pressure conditions are set so that the color influence control type functional masterbatch and the color difference correction type color masterbatch are uniformly dispersed within the base resin and filled into the mold. If the injection speed is excessively low, weld lines or color deviation may increase, and if the injection speed is excessively high, pigment discoloration or surface flow marks may occur due to increased shear heat. Therefore, the injection speed and holding pressure are adjusted considering the thickness of the molded product, the gate position, and the flow length.

[0190] In the above injection step (S800), if the thickness of the molded product increases, the color influence of the functional powder and correction pigment increases; therefore, in the color difference calculation step (S400) and the correction masterbatch setting step (S500), the color correction mixing ratio is set by reflecting the thickness of the molded product.

[0192] 9. Inspection Step (S900)

[0193] The above inspection step (S900) is a step for verifying the color reproducibility, appearance quality, and functionality of a cosmetic container manufactured through the injection step (S800).

[0194] The above color reproducibility is evaluated by the color difference value ΔE of the final injection molded product compared to a target color specimen or a reference color specimen. The color difference value ΔE is calculated based on the lightness value (L*), red-green axis color value (a*), and yellow-blue axis color value (b*) measured at three or more different locations on the exterior surface of the final injection molded product. The final injection molded product is managed so that the average value of the color difference value ΔE calculated at the three or more locations is 2.5 or less.

[0195] The above color values ​​can be measured using a colorimeter and under standard light source D65 and 10-degree observer conditions. At this time, the measurement locations may include different locations selected from the periphery of the gate, the flow end, and the center of the exterior. Accordingly, color deviations in different parts of the molded product, local uneven distribution of functional powder, and non-uniform dispersion of color correction pigments are confirmed.

[0196] The above appearance quality is evaluated based on the presence of whitening, flow marks, pigment clumping, gloss degradation, surface roughness, weld lines, and bubbles. The above appearance quality may be evaluated by one or more methods of visual inspection, gloss measurement, or surface roughness measurement. The above visual inspection may be performed by checking for the occurrence of color stains, inorganic powder aggregation points, pigment aggregation points, and surface defects on the appearance surface of the molded article.

[0197] The above functionality is evaluated as one or more of antibacterial properties, deodorizing properties, UV blocking properties, and storage stability of contents. The antibacterial properties may be evaluated by contacting Escherichia coli, Staphylococcus aureus, or a combination thereof with the surface of a cosmetic container or the surface of a specimen of the same composition, and then calculating the bacterial growth inhibition rate compared to a control specimen.

[0198] The above deodorizing ability can be evaluated by exposing the cosmetic container or a specimen of the same composition to a test gas containing ammonia, acetic acid, or volatile organic compounds, and then calculating the rate of reduction in residual concentration relative to the initial concentration.

[0199] The above UV blocking ability can be evaluated by measuring the UV transmittance or blocking rate in the wavelength range of 280 to 400 nm for the cosmetic container or a specimen of the same composition.

[0200] The storage stability of the above contents can be evaluated by filling the cosmetic contents into the cosmetic container or storing them in contact with a specimen of the same composition for a certain period, and then checking for changes in color, odor, sedimentation, discoloration, or viscosity of the contents.

[0201] In this way, during the inspection step (S900), through the evaluation of color reproducibility, appearance quality, and functionality, it is confirmed whether the color influence control type functional masterbatch and the color difference correction type color masterbatch have been applied appropriately to the final injection molded product for achieving the target color and manifesting functionality.

[0203] The present invention, configured as described above, has a configuration in which a surface-modified composite functional powder comprising silica-coated zinc oxide, alkylsilane-modified zeolite, alumina-silica composite-coated rutile-type titanium dioxide, and spherical silica spacers is prepared as a color influence-controlling functional masterbatch, and the color deviation caused by the input of the color influence-controlling functional masterbatch is corrected with a color difference-correcting color masterbatch.

[0204] Therefore, the present invention can correct color deviations caused by the inherent color or uneven dispersion of functional ingredients in advance, and can reproduce the target color even after injection molding. In addition, since the present invention uniformly disperses functional ingredients and color correction ingredients within a single-layer injection structure, it is possible to manufacture a cosmetic container having antibacterial, deodorizing, UV blocking, and contents storage stability.

[0206] Specific embodiments of the present invention are described below. The following embodiments are examples to illustrate the technical concept of the present invention and are not limited to the scope of the present invention.

[0208] The silica-coated zinc oxide used in the examples below was used in which a silica coating layer of 6 parts by weight was formed on the surface of zinc oxide particles based on 100 parts by weight of zinc oxide. The alkylsilane-modified zeolite was used after surface modification with 2.0 parts by weight of octyltrimethoxysilane based on 100 parts by weight of zeolite. The alumina-silica composite-coated rutile-type titanium dioxide was used in which an alumina-silica composite coating layer of 8 parts by weight was formed based on 100 parts by weight of rutile-type titanium dioxide. The spherical silica spacer used was amorphous spherical silica with an average particle size D50 of 1.2 μm.

[0210] < Example 1 > Preparation of an injection molding material composition for an ABS-based container body

[0211] A composite functional powder before surface modification was prepared by dry mixing 32 parts by weight of silica-coated zinc oxide, 30 parts by weight of alkylsilane-modified zeolite, 26 parts by weight of alumina-silica composite-coated rutile-type titanium dioxide, and 12 parts by weight of spherical silica spacers. The total weight of each component was adjusted to 100 parts by weight.

[0212] The composite functional powder prior to surface modification was pre-dried at 100°C, and then 0.8 parts by weight of 3-glycidoxypropyltrimethoxysilane diluted in ethanol was sprayed onto 100 parts by weight of the composite functional powder prior to surface modification, and a first silane treatment was performed by mixing at 80°C for 30 minutes. Subsequently, 1.2 parts by weight of polyethylene oxide wax having an acid value of 10 to 35 mgKOH / g and a softening point of 95 to 125°C was added to the composite functional powder treated by the first silane, and a second wax treatment was performed by mixing at 110°C for 25 minutes. Accordingly, a surface-modified composite functional powder was prepared in which interfacial affinity and dispersibility were imparted to the entire composite functional powder.

[0213] 30 parts by weight of the above surface-modified composite functional powder, 3 parts by weight of an interfacial dispersant for a masterbatch containing ethylenebisstearamide and zinc stearate, and the remainder of an ABS-based carrier resin were mixed to produce a total of 100 parts by weight of an ABS-based color-influence-controlling functional masterbatch raw material. Subsequently, the raw material was melt-kneaded at 200°C, and the extruded product was cooled and cut to produce an ABS-based color-influence-controlling functional masterbatch.

[0214] Subsequently, a functional reference specimen was prepared by mixing ABS with the ABS-based color influence control functional masterbatch, and the CIE Lab* color value of the functional reference specimen was measured. The measured color value was compared with the color value of the target color specimen to calculate ΔL*, Δa*, Δb*, and ΔE, and the mixing ratio of the composite correction pigment was set according to the calculated color deviation.

[0215] The above composite correction pigment was prepared to include 60 parts by weight of rutile-type titanium dioxide, 20 parts by weight of CI Pigment Yellow 42, 12 parts by weight of CI Pigment Red 101, 5 parts by weight of CI Pigment Blue 15:3, and 3 parts by weight of CI Pigment Black 7. 24 parts by weight of the above composite correction pigment, 3 parts by weight of a dispersant for color masterbatch, and the remainder of an ABS-based carrier resin were mixed to prepare a total of 100 parts by weight of an ABS-based color difference correction type color masterbatch raw material. Subsequently, the above raw material was melt-kneaded and pelletized to prepare an ABS-based color difference correction type color masterbatch.

[0216] Next, after drying the ABS at 80°C for 3 hours, 5.0 parts by weight of the ABS-based color influence control type functional masterbatch, 3.5 parts by weight of the ABS-based color difference correction type color masterbatch, and 0.8 parts by weight of an interface-fixing type dispersion stabilizer were mixed with 100 parts by weight of ABS. The interface-fixing type dispersion stabilizer was configured to include 45 parts by weight of polyethylene oxide wax and 55 parts by weight of maleic anhydride graft ABS-based resin.

[0217] The above mixture was low-shear melt-kneaded at 205°C under conditions of a screw rotation speed of 120 rpm and a molten resin residence time of 60 seconds, and the extruded product was cooled and cut to produce an injection pellet for an ABS-based container body. The injection pellet was fed into an injection molding machine and injection molded at a cylinder temperature of 220°C and a mold temperature of 55°C to produce an ABS-based cosmetic container body.

[0219] < Example 2 > Preparation of an injection molding material composition for PP-based cap parts

[0220] A composite functional powder before surface modification was prepared by dry mixing 32 parts by weight of silica-coated zinc oxide, 30 parts by weight of alkylsilane-modified zeolite, 26 parts by weight of alumina-silica composite-coated rutile-type titanium dioxide, and 12 parts by weight of spherical silica spacers. The total weight of each component was adjusted to 100 parts by weight.

[0221] The composite functional powder prior to surface modification was pre-dried at 100°C, and then 0.8 parts by weight of vinyltrimethoxysilane diluted in ethanol was sprayed onto 100 parts by weight of the composite functional powder prior to surface modification, and a first silane treatment was performed by mixing at 80°C for 30 minutes. Subsequently, 1.2 parts by weight of polyethylene oxide wax were added to the composite functional powder treated by the first silane treatment, and a second wax treatment was performed by mixing at 110°C for 25 minutes. Accordingly, a surface-modified composite functional powder with improved interfacial affinity with a PP-based carrier resin was prepared.

[0222] 30 parts by weight of the above surface-modified composite functional powder, 3 parts by weight of an interfacial dispersant for the masterbatch, and the remainder of a PP-based carrier resin were mixed to produce a total of 100 parts by weight of a PP-based color-influence-controlling functional masterbatch raw material. Subsequently, the raw material was melt-kneaded at 195°C, and the extruded product was cooled and cut to produce a PP-based color-influence-controlling functional masterbatch.

[0223] Subsequently, a functional reference specimen was prepared by mixing PP with the above-mentioned PP-based color influence control functional masterbatch, and the CIE Lab* color value of the functional reference specimen was measured. The measured color value was compared with the color value of the target color specimen to calculate ΔL*, Δa*, Δb*, and ΔE, and the mixing ratio and input amount of the composite correction pigment were set according to the calculated color deviation.

[0224] The above composite correction pigment was prepared to include 58 parts by weight of rutile-type titanium dioxide, 22 parts by weight of CI Pigment Yellow 42, 12 parts by weight of CI Pigment Red 101, 5 parts by weight of CI Pigment Blue 15:3, and 3 parts by weight of CI Pigment Black 7. 24 parts by weight of the above composite correction pigment, 3 parts by weight of a dispersant for color masterbatch, and the remainder of a PP-based carrier resin were mixed to prepare a total of 100 parts by weight of PP-based color difference correction type color masterbatch raw material. Subsequently, the above raw material was melt-kneaded and pelletized to prepare a PP-based color difference correction type color masterbatch.

[0225] Next, after drying the PP at 70°C for 2 hours, 6.0 parts by weight of the PP-based color influence control type functional masterbatch, 4.8 parts by weight of the PP-based color difference correction type color masterbatch, 1.0 parts by weight of an interface-fixing dispersion stabilizer, and 5.0 parts by weight of a polyolefin elastomer were mixed with 100 parts by weight of PP. The interface-fixing dispersion stabilizer was configured to include 45 parts by weight of polyethylene oxide wax and 55 parts by weight of maleic anhydride grafted polypropylene.

[0226] The above polyolefin elastomer used an ethylene-α-olefin copolymer comprising ethylene and an α-olefin having 3 to 8 carbon atoms. The polyolefin elastomer has a density of 0.850 to 0.900 g / cm³. 3 And, a melt flow index of 0.5 to 20 g / 10 min was used under conditions of 190℃ and 2.16 kg. The above mixture was low-shear melt-kneaded at 200°C under conditions of a screw rotation speed of 120 rpm and a molten resin residence time of 60 seconds, and the extruded product was cooled and cut to produce injection pellets for PP-based cap parts. The injection pellets were fed into an injection molding machine and injection molded at a cylinder temperature of 210°C and a mold temperature of 40°C to produce PP-based one-touch caps.

[0228] < Example 3 > Preparation of an Injection Molding Material Composition for PETG-based Translucent Parts

[0229] A composite functional powder before surface modification was prepared by dry mixing 32 parts by weight of silica-coated zinc oxide, 30 parts by weight of alkylsilane-modified zeolite, 26 parts by weight of alumina-silica composite-coated rutile-type titanium dioxide, and 12 parts by weight of spherical silica spacers. The total weight of each component was adjusted to 100 parts by weight.

[0230] The composite functional powder prior to surface modification was pre-dried at 100°C, and then 0.8 parts by weight of 3-aminopropyltriethoxysilane diluted in ethanol was sprayed onto 100 parts by weight of the composite functional powder prior to surface modification, and a first silane treatment was performed by mixing at 80°C for 30 minutes. Subsequently, 1.2 parts by weight of polyethylene oxide wax were added to the composite functional powder treated by the first silane treatment, and a second wax treatment was performed by mixing at 110°C for 25 minutes. Accordingly, a surface-modified composite functional powder with improved interfacial affinity with a PETG-based carrier resin was prepared.

[0231] 24 parts by weight of the above surface-modified composite functional powder, 3 parts by weight of an interfacial dispersant for the masterbatch, and the remainder of the PETG-based carrier resin were mixed to produce a total of 100 parts by weight of PETG-based color-influence-controlled functional masterbatch raw material. Subsequently, the raw material was melt-kneaded at 230°C, and the extruded product was cooled and cut to produce a PETG-based color-influence-controlled functional masterbatch.

[0232] Subsequently, a functional reference specimen was prepared by mixing PETG with the above PETG-based color influence control functional masterbatch, and the CIE Lab* color value of the functional reference specimen was measured. The measured color value was compared with the color value of the target color specimen to calculate ΔL*, Δa*, Δb*, and ΔE, and the mixing ratio and input amount of the composite correction pigment were set according to the calculated color deviation.

[0233] The above composite correction pigment was prepared to include 54 parts by weight of rutile-type titanium dioxide, 24 parts by weight of CI Pigment Yellow 42, 14 parts by weight of CI Pigment Red 101, 6 parts by weight of CI Pigment Blue 15:3, and 2 parts by weight of CI Pigment Black 7. 20 parts by weight of the above composite correction pigment, 3 parts by weight of a dispersant for color masterbatch, and the remainder of a PETG-based carrier resin were mixed to prepare a total of 100 parts by weight of PETG-based color difference correction type color masterbatch raw material. Subsequently, the above raw material was melt-kneaded and pelletized to prepare a PETG-based color difference correction type color masterbatch.

[0234] Next, after drying the PETG at 75°C for 4 hours, 3.0 parts by weight of the PETG-based color influence control functional masterbatch, 2.4 parts by weight of the PETG-based color difference correction color masterbatch, and 0.6 parts by weight of an interface-fixing dispersion stabilizer were mixed with 100 parts by weight of PETG. The interface-fixing dispersion stabilizer was configured to include 45 parts by weight of polyethylene oxide wax and 55 parts by weight of maleic anhydride grafted polyester resin.

[0235] The above mixture was low-shear melt-kneaded at 235°C under conditions of a screw rotation speed of 120 rpm and a molten resin residence time of 60 seconds, and the extruded product was cooled and cut to produce injection pellets for PETG-based translucent parts. The injection pellets were fed into an injection molding machine and injection molded at a cylinder temperature of 245°C and a mold temperature of 45°C to produce PETG-based translucent cosmetic container parts.

[0237] < Comparative Example 1 > ABS-based injection molding material composition with directly added functional powder

[0238] ABS was dried at 80°C for 3 hours. Subsequently, 1.5 parts by weight of the pre-surface modification composite functional powder of Example 1, 3.5 parts by weight of the ABS-based color difference correction type color masterbatch of Example 1, and 0.8 parts by weight of an interface-fixing dispersion stabilizer were mixed with 100 parts by weight of ABS. At this time, the pre-surface modification composite functional powder was not subjected to primary silane treatment and secondary wax treatment, and was directly added without being prepared as a color influence control type functional masterbatch.

[0239] The amount of 1.5 parts by weight of the composite functional powder before surface modification was set to correspond to the content of the surface-modified composite functional powder in 5.0 parts by weight of the ABS-based color influence control type functional masterbatch added to 100 parts by weight of ABS in Example 1.

[0240] An ABS-based cosmetic container body was manufactured by melt-kneading and injection molding the above mixture under the same conditions as in Example 1.

[0242] < Comparative Example 2 > ABS-based injection molding material composition not containing color difference correction type color masterbatch

[0243] ABS was dried at 80°C for 3 hours. Subsequently, 5.0 parts by weight of the ABS-based color influence control type functional masterbatch of Example 1 and 0.8 parts by weight of an interface-fixing type dispersion stabilizer were mixed with 100 parts by weight of ABS. At this time, the color difference correction type color masterbatch was not added.

[0244] An ABS-based cosmetic container body was manufactured by melt-kneading and injection molding the above mixture under the same conditions as in Example 1.

[0246] < Comparative Example 3 > ABS-based injection molding material composition not containing an interface-fixing dispersion stabilizer

[0247] ABS was dried at 80°C for 3 hours. Subsequently, 5.0 parts by weight of the ABS-based color influence control type functional masterbatch of Example 1 and 3.5 parts by weight of the ABS-based color difference correction type color masterbatch of Example 1 were mixed with 100 parts by weight of ABS. At this time, the interface-fixing dispersion stabilizer was not added.

[0248] An ABS-based cosmetic container body was manufactured by melt-kneading and injection molding the above mixture under the same conditions as in Example 1.

[0250] < Comparative Example 4 > ABS-based injection molding material composition comprising a functional masterbatch that has not undergone two-stage surface modification

[0251] A composite functional powder before surface modification with the same composition as in Example 1 was used, but without performing the first silane treatment and the second wax treatment. 30 parts by weight of the composite functional powder before surface modification, 3 parts by weight of an interfacial dispersant for the masterbatch, and the remainder of an ABS-based carrier resin were mixed to prepare a total of 100 parts by weight of an ABS-based functional masterbatch raw material. Subsequently, the raw material was melt-kneaded and pelletized under the same conditions as in Example 1 to produce an ABS-based functional masterbatch without two-stage surface modification.

[0252] ABS was dried at 80°C for 3 hours. Subsequently, 5.0 parts by weight of an ABS-based functional masterbatch that had not undergone the above 2-step surface modification, 3.5 parts by weight of the ABS-based color difference correction type color masterbatch of Example 1, and 0.8 parts by weight of an interface-fixing dispersion stabilizer were mixed with 100 parts by weight of ABS.

[0253] An ABS-based cosmetic container body was manufactured by melt-kneading and injection molding the above mixture under the same conditions as in Example 1.

[0255] < Comparative Example 5 > Injection molding material composition for PP-based cap parts not containing polyolefin elastomer

[0256] PP was dried at 70°C for 2 hours. Subsequently, 6.0 parts by weight of the PP-based color influence control type functional masterbatch of Example 2, 4.8 parts by weight of the PP-based color difference correction type color masterbatch of Example 2, and 1.0 parts by weight of an interface-fixing dispersion stabilizer were mixed with 100 parts by weight of PP. At this time, no polyolefin elastomer was added.

[0257] A PP-based one-touch cap was manufactured by melt-kneading and injection-molding the above mixture under the same conditions as in Example 2.

[0259] < Comparative Example 6 > ABS-based injection molding material composition using a carrier resin of a different series from the base resin

[0260] ABS was dried at 80°C for 3 hours. Subsequently, 5.0 parts by weight of a color influence control type functional masterbatch prepared using a PP-based carrier resin, 3.5 parts by weight of a color difference correction type color masterbatch prepared using a PP-based carrier resin, and 0.8 parts by weight of an interface-fixing dispersion stabilizer were mixed with 100 parts by weight of ABS.

[0261] The color influence control type functional masterbatch using the above-mentioned PP-based carrier resin was prepared in the same manner as the PP-based color influence control type functional masterbatch of Example 2. The color difference correction type color masterbatch using the above-mentioned PP-based carrier resin was prepared in the same manner as the PP-based color difference correction type color masterbatch of Example 2.

[0262] An ABS-based cosmetic container body was manufactured by melt-kneading and injection molding the above mixture under the same conditions as in Example 1.

[0264] < Experimental Example >

[0265] < Experimental Example 1 > Color Reproducibility Evaluation

[0266] Color reproducibility was evaluated for the injection molded products prepared in Examples 1 to 3 and Comparative Examples 1 to 6 above.

[0267] Color reproducibility was evaluated as the color difference value ΔE of the final injection-molded product compared to the target color specimen. Example 1 and Comparative Examples 1 to 4 and Comparative Example 6 were evaluated based on the target color specimen for the ABS-based container body, Example 2 and Comparative Example 5 were evaluated based on the target color specimen for the PP-based cap part, and Example 3 was evaluated based on the target color specimen for the PETG-based translucent part.

[0268] Color values ​​were measured using a colorimeter under standard light source D65 and 10-degree observer conditions. Three different measurement locations were established on the exterior surface of the injection-molded product, including the periphery of the gate, the flow end, and the center of the exterior. At each location, lightness values ​​(L*), red-green axis color values ​​(a*), and yellow-blue axis color values ​​(b*) were measured, and ΔL*, Δa*, and Δb* were calculated relative to the target color specimen. Subsequently, the average ΔE was calculated based on the average values ​​of ΔL*, Δa*, and Δb* obtained from the three locations. The above ΔE is given by ΔE=[(ΔL*) 2 + (Δa*) 2 + (Δb*) 2 ] 1 / 2 It was calculated by.

[0269] The results are shown in [Table 1] below.

[0270]

[0271] As shown in [Table 1] above, Examples 1 to 3 all had an average ΔE of 2.5 or less, indicating excellent color reproducibility for the target color. This is because the functional powder was prepared as a color influence-controlling functional masterbatch, and a color difference-correcting color masterbatch was applied according to the color deviation of the functional reference specimen, thereby effectively correcting the deviations of ΔL*, Δa*, and Δb* caused by the functional powder.

[0272] On the other hand, in Comparative Example 1, the functional powder was directly introduced in powder form, resulting in increased color deviation, and in Comparative Example 2, a color difference correction type color masterbatch was not applied, so the deviations of ΔL*, Δa*, and Δb* caused by the functional powder were not corrected. In addition, in Comparative Examples 3 and 4, the interface-fixing type dispersion stabilizer or the two-stage surface modification was omitted, respectively, resulting in reduced dispersion uniformity, and in Comparative Example 6, the application of a heterogeneous carrier resin caused interfacial non-uniformity, leading to an increase in the average ΔE.

[0274] < Experimental Example 2 > Evaluation of Appearance Quality and Dispersion Stability

[0275] The appearance quality and dispersion stability of the injection molded products prepared in Examples 1 to 3 and Comparative Examples 1 to 6 above were evaluated.

[0276] Appearance quality and dispersion stability were evaluated based on gloss, surface roughness, and the number of aggregate points on the exterior surface of the injection-molded product. Gloss was measured using a 60-degree gloss meter, and surface roughness was evaluated by measuring the arithmetic mean roughness (Ra) at the center of the exterior surface of the injection-molded product. The number of aggregate points was 100 cm⁻¹. 2 It was confirmed through visual and magnified observation based on the external surface.

[0277] The appearance quality is 3 cohesion points / 100 cm 2 If the surface roughness Ra is 0.30 μm or less, it was evaluated as excellent, and if the above criteria were not met, it was evaluated as defective. In this case, glossiness was used as an auxiliary indicator to check whether the appearance gloss of the injection molded product had deteriorated.

[0278] The results are shown in [Table 2] below.

[0279]

[0280] As shown in [Table 2] above, Examples 1 to 3 have 1 aggregation point / 100 cm 2The surface roughness Ra was measured to be 0.22 μm or less, indicating excellent appearance quality and dispersion stability. This is because the dispersibility of the inorganic functional powder and the correcting pigment was stably secured through primary silane treatment and secondary wax treatment of the composite functional powder, masterbatch formation using a carrier resin of the same system as the base resin, and the application of an interface-fixing dispersion stabilizer.

[0281] On the other hand, in Comparative Example 1, the functional powder was directly introduced in powder form, resulting in an increase in the number of aggregation points and surface roughness, and in Comparative Example 3, the interfacial stability between the functional powder and the corrective pigment was reduced because the interface-fixing dispersion stabilizer was omitted. In Comparative Example 4, the two-step surface modification of the composite functional powder was omitted, resulting in increased re-aggregation and surface roughness of the functional powder, and in Comparative Example 6, interfacial non-uniformity and surface defects increased due to the application of a heterogeneous carrier resin.

[0282] Meanwhile, Comparative Example 2 is a composition in which the color difference correction type color masterbatch is omitted, but the appearance quality is maintained at a level similar to the example because it includes a color influence control type functional masterbatch and an interface-fixing type dispersion stabilizer. In addition, Comparative Example 5 is a composition for PP-based cap parts in which the polyolefin elastomer is omitted, but it was confirmed that the appearance quality is excellent because it includes a functional masterbatch, a color difference correction type color masterbatch, and an interface-fixing type dispersion stabilizer.

[0284] < Experimental Example 3 > Evaluation of Antibacterial, Deodorizing, and UV Blocking Properties

[0285] Plate-shaped specimens having the same composition as the injection-molded articles prepared in Examples 1 to 3 and Comparative Examples 1 to 6 were prepared, and antibacterial, deodorizing, and UV blocking properties were evaluated.

[0286] Antibacterial activity was evaluated by contacting Escherichia coli and Staphylococcus aureus, respectively, onto the surface of plate-shaped specimens cut to the same size, and calculating the bacterial growth inhibition rate after 24 hours. At this time, the control specimen was set as an injection-molded specimen of the same resin system that did not contain functional powder.

[0287] Deodorizing performance was evaluated by placing plate-shaped specimens of the same area in a test chamber where ammonia and acetic acid were each adjusted to an initial concentration of 100 ppm, and then measuring the residual concentration after 24 hours to calculate the removal rate.

[0288] UV blocking performance was evaluated by measuring the average UV transmittance in the wavelength range of 280 to 400 nm for a plate-shaped specimen with a thickness of 1.5 mm and calculating the average UV blocking rate based on this.

[0289] The results are shown in [Table 3] below.

[0290]

[0291] As shown in [Table 3] above, Examples 1 to 3 were all measured to have an inhibition rate of bacterial growth against Escherichia coli and Staphylococcus aureus of 98% or higher, an ammonia removal rate of 82.5% or higher, and a UV blocking rate of 88.6% or higher, indicating excellent antibacterial, deodorizing, and UV blocking properties. This is because the composite functional powder containing silica-coated zinc oxide, alkylsilane-modified zeolite, alumina-silica composite-coated rutile-type titanium dioxide, and spherical silica spacers was stably dispersed within the injection-molded product.

[0292] In Comparative Example 1, the functional powder was directly introduced in powder form, which reduced the dispersion uniformity of the functional powder, and in Comparative Example 4, the two-step surface modification of the composite functional powder was omitted, which increased the re-aggregation of the functional powder. Accordingly, Comparative Examples 1 and 4 were measured to have lower antibacterial, deodorizing, and UV blocking properties compared to Examples 1 to 3.

[0293] Comparative Example 2 is a composition in which the color difference correction type color masterbatch is omitted, and the content and dispersion structure of the functional powder are maintained, so the antibacterial, deodorizing, and UV blocking properties are at a level similar to that of the example. In Comparative Example 3, the interface-fixing type dispersion stabilizer is omitted, so the uniform dispersion of the functional powder is partially reduced, and in Comparative Example 6, the functional evaluation value is reduced due to interfacial non-uniformity caused by the application of a heterogeneous carrier resin.

[0295] < Experimental Example 4 > Evaluation of Repeatable Opening / Closing Performance and Fastening Stability of PP-based Cap Components

[0296] The PP-based one-touch caps manufactured in Example 2 and Comparative Example 5 above were evaluated for repeated opening and closing, hinge recovery, fastening stability, and shock absorption.

[0297] Repeatability was evaluated on 10 one-touch caps for each group. After opening and closing each one-touch cap 5,000 times, the occurrence of whitening and cracking in the hinge area was visually checked.

[0298] Fastening stability was evaluated by measuring the fastening force before repeated opening and closing and the fastening force after repeated opening and closing, and then calculating the fastening force retention rate according to the following formula.

[0299] Locking force retention rate (%) = (Close-up force after repeated opening / closing / Locking force before repeated opening / closing) × 100

[0300] Shock absorption was evaluated by dropping 10 one-touch caps from each group from a height of 1.0 m once and visually checking for cracks.

[0301] The results are shown in [Table 4] below.

[0302]

[0303] As shown in [Table 4] above, Example 2 did not experience whitening or cracking in the hinge part even after 5,000 repeated opening and closing cycles, the fastening force retention rate was maintained at 96.5%, and no cracking occurred after dropping. This is because the elastic recovery, repeated opening and closing, and shock absorption of the hinge part were improved by including a polyolefin elastomer in the injection molding raw material composition for PP-based cap parts.

[0304] On the other hand, Comparative Example 5 did not contain polyolefin elastomer, so whitening and cracking occurred in the hinge part after 5,000 repeated opening and closing cycles, the fastening force retention rate decreased to 78.4%, and the number of cracks occurring after dropping increased. Accordingly, it was confirmed that the application of polyolefin elastomer in PP-based cap parts is effective in improving repeated opening and closing performance, hinge restorability, fastening stability, and shock absorption.

[0306] < Experimental Example 5 > Evaluation of Content Storage Stability

[0307] Plate-shaped specimens of the same composition as the injection-molded articles prepared in Examples 1 to 3 and Comparative Examples 1 to 6 were prepared, and storage stability for cosmetic contents was evaluated.

[0308] The storage stability of the contents was evaluated by preparing plate-shaped specimens of each composition with the same surface area, storing them at 45°C for 4 weeks in contact with the same cosmetic contents, and checking the color change value ΔE, viscosity change rate, occurrence of precipitation, and odor change of the contents before and after storage.

[0309] The color change value ΔE of the contents is determined by measuring the CIE L*a*b* color value of the contents before storage and the CIE L*a*b* color value of the contents after storage, ΔE=[(ΔL*) 2 + (Δa*) 2 + (Δb*) 2 ] 1 / 2It was calculated by [method]. The viscosity change rate was calculated as the rate of change in viscosity after storage relative to the viscosity before storage. The occurrence of precipitation was confirmed by visual inspection of the contents after storage, and the change in odor was confirmed by comparison with the contents before storage.

[0310] Storage stability was evaluated as excellent if the change in color of the contents ΔE was 1.0 or less, the change in viscosity rate was 3.0% or less, and there was no sedimentation or change in odor. It was evaluated as average if the change in color of the contents ΔE was 1.5 or less, the change in viscosity rate was 6.0% or less, sedimentation was fine sedimentation or less, and there was no change in odor. If the above average criteria were not met, it was evaluated as poor.

[0311] The results are shown in [Table 5] below.

[0312]

[0313] As shown in [Table 5] above, Examples 1 to 3 had excellent storage stability of the contents, with a color change value ΔE of 0.64 or less and a viscosity change rate of 2.8% or less even after being stored at 45°C for 4 weeks, and no sedimentation or change in odor occurred. This is because the composite functional powder was surface-modified and master-batched to be uniformly dispersed within the injection-molded product, and the interfacial stability between the functional powder and the base resin was secured by the interface-fixing dispersion stabilizer.

[0314] On the other hand, in Comparative Example 1, the functional powder was directly added in powder form, which reduced the contact stability with the contents, and in Comparative Example 4, the two-step surface modification of the composite functional powder was omitted, which increased the re-aggregation of the functional powder. Accordingly, in Comparative Examples 1 and 4, the color change, viscosity change, fine sedimentation, and odor change of the contents increased.

[0315] In Comparative Example 3, the interface-fixing dispersion stabilizer was omitted, so the color change value and viscosity change rate of the contents increased compared to the example, but were evaluated to be within the standard range. In Comparative Example 6, interfacial non-uniformity occurred due to the application of a heterogeneous carrier resin, resulting in reduced storage stability of the contents. Meanwhile, Comparative Examples 2 and 5 are comparative examples related to the omission of a color difference correction type color masterbatch or a polyolefin elastomer, respectively, and the storage stability of the contents was found to be at a level similar to that of the example.

[0317] Although a preferred embodiment of the present invention has been described above with reference to the attached drawings, those skilled in the art will understand that the present invention may be implemented in other specific forms without altering its technical concept or essential features. Therefore, the embodiment described above should be understood as illustrative in all respects and not restrictive.

Claims

Claim 1 An injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality, comprising, for every 100 parts by weight of a base resin, 1.8 to 9.5 parts by weight of a color influence control type functional masterbatch, 1.2 to 7.2 parts by weight of a color difference correction type color masterbatch, and 0.08 to 2.4 parts by weight of an interface-fixing dispersion stabilizer, wherein the color influence control type functional masterbatch is configured in the form of pellets in which a surface-modified composite functional powder is dispersed within a carrier resin, and the color difference correction type color masterbatch is configured to correct deviations in CIE Lab* color values ​​caused by the addition of the color influence control type functional masterbatch. Claim 2 An injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality, characterized in that, in claim 1, the base resin is selected from acrylonitrile-butadiene-styrene copolymer (ABS), polypropylene (PP), and polyethylene terephthalate glycol (PETG), and the carrier resin of the color influence control type functional masterbatch and the color difference correction type color masterbatch is composed of a resin of the same system as the base resin. Claim 3 In claim 1, the color influence control type functional masterbatch comprises 18 to 42 parts by weight of a surface-modified composite functional powder, 1.5 to 6.0 parts by weight of an interfacial dispersant for the masterbatch, and the remainder of a carrier resin, wherein the total of the surface-modified composite functional powder, the interfacial dispersant for the masterbatch, and the carrier resin is 100 parts by weight, and the surface-modified composite functional powder comprises silica-coated zinc oxide, alkylsilane-modified zeolite, alumina-silica composite-coated rutile-type titanium dioxide, and spherical silica spacers, characterized in that the injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality is characterized. Claim 4 In claim 3, the surface-modified composite functional powder is formed by sequentially performing a first silane treatment and a second wax treatment on the composite functional powder prior to surface modification, and 100 parts by weight of the composite functional powder prior to surface modification comprises 26 to 36 parts by weight of silica-coated zinc oxide, 24 to 34 parts by weight of alkylsilane-modified zeolite, 20 to 30 parts by weight of alumina-silica composite-coated rutile-type titanium dioxide, and 8 to 16 parts by weight of spherical silica spacer, the first silane treatment is performed using 0.35 to 1.25 parts by weight of a silane-based coupling agent per 100 parts by weight of the composite functional powder prior to surface modification, and the second wax treatment is performed using 0.45 to 1.80 parts by weight of polyethylene oxide wax per 100 parts by weight of the composite functional powder prior to surface modification, and the average particle size D50 of the surface-modified composite functional powder is 0.3 to 2.8 An injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality, characterized by being μm. Claim 5 In claim 1, the color difference correction type color masterbatch comprises 10 to 36 parts by weight of a composite correction pigment, 1 to 6 parts by weight of a dispersant for the color masterbatch, and the remainder of a carrier resin, wherein the total of the composite correction pigment, the dispersant for the color masterbatch, and the carrier resin is 100 parts by weight, and the 100 parts by weight of the composite correction pigment comprises 35 to 68 parts by weight of a white correction pigment, 8 to 24 parts by weight of a yellow correction pigment, 3 to 14 parts by weight of a red correction pigment, 0.5 to 7 parts by weight of a blue correction pigment, and 0.2 to 5 parts by weight of a black correction pigment, characterized in that the injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality is characterized in that Claim 6 In claim 1, the interface-fixing dispersion stabilizer comprises 30 to 65 parts by weight of polyethylene oxide wax and 35 to 70 parts by weight of maleic anhydride graft resin, wherein the total of the polyethylene oxide wax and maleic anhydride graft resin is 100 parts by weight; and the injection molding raw material composition comprises, for 100 parts by weight of ABS, 2.0 to 7.5 parts by weight of an ABS-based color influence control type functional masterbatch, 1.5 to 5.5 parts by weight of an ABS-based color difference correction type color masterbatch, and 0.10 to 1.8 parts by weight of an interface-fixing dispersion stabilizer; for 100 parts by weight of PP, 2.5 to 8.5 parts by weight of a PP-based color influence control type functional masterbatch, 2.8 to 6.8 parts by weight of a PP-based color difference correction type color masterbatch, 0.12 to 2.0 parts by weight of an interface-fixing dispersion stabilizer, and polyolefin An injection molding raw material composition for cosmetic containers with improved color reproducibility and functionality, characterized by comprising any one of: a composition for PP-based cap parts comprising 3.5 to 6.5 parts by weight of an elastomer; and a composition for PETG-based translucent parts comprising 1.8 to 4.8 parts by weight of a PETG-based color influence control type functional masterbatch, 1.2 to 3.8 parts by weight of a PETG-based color difference correction type color masterbatch, and 0.08 to 1.2 parts by weight of an interface-fixing type dispersion stabilizer, based on 100 parts by weight of PETG. Claim 7 A method for manufacturing a cosmetic container with improved color reproducibility and functionality comprises: a resin selection and drying step (S100) of selecting and drying a base resin among ABS, PP, or PETG according to the part to be manufactured; a powder surface modification step (S200) of sequentially performing a first silane treatment and a second wax treatment on a composite functional powder comprising silica-coated zinc oxide, alkylsilane-modified zeolite, alumina-silica composite-coated rutile-type titanium dioxide, and spherical silica spacers to produce a surface-modified composite functional powder; a functional masterbatch manufacturing step (S300) of melt-kneading the surface-modified composite functional powder with a carrier resin and an interfacial dispersant for the masterbatch to produce a color-influence-controlling functional masterbatch; measuring the lightness value (L*), red-green axis color value (a*), and yellow-blue axis color value (b*) of a functional reference specimen comprising the base resin and the color-influence-controlling functional masterbatch, and ΔL*, Δa*, compared to a target color specimen A color difference calculation step (S400) for calculating Δb* and a color difference value ΔE; a correction masterbatch setting step (S500) for setting the correction pigment combination and input amount of a color difference correction type color masterbatch according to ΔL*, Δa*, Δb*, and ΔE calculated in the color difference calculation step (S400); a raw material mixing step (S600) for manufacturing an injection raw material by mixing the base resin, a color influence control type functional masterbatch, a color difference correction type color masterbatch, and an interface-fixing type dispersion stabilizer; a pelletizing step (S700) for manufacturing injection pellets by melt-kneading and cutting the injection raw material; an injection step (S800) for manufacturing a cosmetic container by injection molding the injection pellets; and an inspection step (S900) for inspecting the color reproducibility, appearance quality, and functionality of the cosmetic container, wherein the color difference value ΔE is ΔE=[(ΔL*) 2 + (Δa*) 2 + (Δb*) 2 ] 1 / 2 A method for manufacturing a cosmetic container with improved color reproducibility and functionality, characterized in that the correction masterbatch setting step (S500) is calculated by the above, and the correction masterbatch setting step is a step of setting the correction pigment combination or input amount of a color difference correction type color masterbatch so that the color difference value ΔE relative to the reference color of the final injection molded product is 2.5 or less.

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