Blown multi-layer article having a color gradient

Abstract

The present invention provides a blow molded multi-layer article having a hollow body defined by a wall having an inner surface and an outer surface. The outer surface has an axial color gradient. The wall has a plurality of layers, and at least one layer optionally contains an effect pigment and / or a light-shielding pigment.

Description

Technical Field

[0001] The present invention generally relates to blow molded articles having a color gradient, and more particularly to blow molded multi-layer articles having at least one layer comprising effect pigments and / or light-shielding pigments that contribute to the generation of color gradients and other visual effects. The present invention also relates to preforms for manufacturing such articles. Background Art

[0002] Consumers desire to purchase articles that attract their attention due to their unique and / or high-quality appearance on store shelves and / or web pages / applications, especially hair and beauty products in blow molded containers. During use, it is important that consumers are impressed not only by the appearance of the article but also by its functionality, feel, and integrity.

[0003] To make an article that implies luxury and quality stand out, it may be desirable for the article to have a color gradient. If the color gradient is across the entire article and the surface of the article is shiny, it can be particularly attractive. Shiny articles typically can have a smooth outer surface, which can enhance the degree of light reflected from the surface (i.e., for a smoother surface, the specular reflectance is relatively high).

[0004] The combination of a color gradient with effect pigments can give the article a bright, pearlescent, iridescent, glittery, dazzling, and / or metallic effect. Effect pigments have an angle-dependent optical effect when dispersed in a medium such as a coating or a plastic resin, due to their flaky structure and their alignment within the medium. Additionally, it may also be desirable for the article to have sufficient opacity throughout the entire volume of the unit such that the fill line of the product remains hidden from the consumer.

[0005] Currently, some blow molded articles having simple, non-angle-dependent color gradients can be manufactured by varying the thickness of a colored core. However, this method lacks the ability to control the opacity of the article throughout its entire volume. Additionally, during use, these articles can be fragile and the layers can separate (delaminate). Methods to mitigate delamination include incorporating adhesives between the layers and / or compatibilizers within the layers 202180008258.4

[0006] Agents. Articles made using this method also tend to use more plastic compared to standard blow molded articles.

[0007] In addition, incorporating effect pigments and / or opacifying pigments into large-scale blow-molded articles can be expensive because it is difficult to provide the weight percentage of pigment particle loading required to achieve the desired optical effect in the case of large-volume disposable packaging. Once dispersed within the blow-molded article, the article typically has poor gloss and high haze, which reduces the beneficial optical appearance of the pigments. Without being bound by theory, it is believed that this is due to the non-uniformity of the outer surface of the article when there are effect pigment particles and / or opacifying pigment particles due to the proportion of particles exposed near or at the surface of the article.

[0008] One solution to increase gloss is to produce preforms and resulting containers where the inner layer contains pigments and the outer layer is transparent and may also contain colorants. These products are typically manufactured by a two-step process (i.e., a method of sequentially introducing the materials that make up each layer, such as co-molding / overmolding, where the individual layers are molded one after another in subsequent steps; or two-step injection, where the material for the outer layer is first injected into the mold cavity and subsequently the material for the inner layer is injected into the mold cavity). However, we have observed that in some cases, such construction methods can result in poor mechanical resistance of the finished product, such that the layers delaminate during use.

[0009] One way to create a color gradient with effect pigments and / or opacifying pigments is to apply the gradient (e.g., by painting or printing) onto the blow-molded article. However, this method increases the complexity and cost of article manufacturing and is generally not sustainable in mass production of blow-molded articles. Additionally, containers manufactured by this method are typically less durable because the paint / printing may scrape off during filling, transportation, and use.

[0010] Accordingly, there is still a need for blow-molded articles having a color gradient, which are obtained by incorporating colorants including pigments in alternative materials where delamination of the materials is mitigated. There is also a need for blow-molded articles having a color gradient, where the colorants are incorporated into materials including dyes, pigments, and combinations of dyes and pigments. There is also a need for blow-molded articles having a color gradient, where the colorants incorporated into the materials include at least one effect pigment and / or opacifying pigment. The article may have high opacity throughout its volume. The article may be resistant to delamination without any adhesives or compatibilizers. SUMMARY OF THE INVENTION

[0011] The present invention provides a blow-molded multi-layer article comprising: a hollow body defined by a wall including an inner surface and an outer surface; and a neck extending from the body to an orifice; wherein at least a first portion of the wall comprises at least three layers, the at least three layers including: 202180008258.4

[0012] Two A layers forming the outer and inner surfaces of the wall, and a B layer located between the A layers; wherein the A layers are transparent and contain a coloring dye or pigment; wherein the B layer contains an effect pigment and / or a light-shielding pigment; wherein the A layers and the B layer contain a thermoplastic resin; wherein the thickness of the A layers varies; wherein the outer surface has an axial color gradient formed by the components of the A layer that form the outer surface. Description of the Drawings

[0013] Although this specification concludes with claims that particularly point out and distinctly claim the subject matter of the invention, it is believed that the invention will be more readily understood from the following description taken in conjunction with the accompanying drawings, in which:

[0014] Figure 1 is a front view of an article having a color gradient and a glossy surface;

[0015] Figure 2 is a cross-sectional view of a preform having a color gradient and a glossy surface;

[0016] Figure 3 is a photograph of a cross-section of a preform taken with a microscope;

[0017] Figure 4A is taken with a microscope Figure 3 of a cross-section of the preform at point A;

[0018] Figure 4B is taken with a microscope Figure 3 of a cross-section of the preform at point B;

[0019] Figure 4C is taken with a microscope Figure 3 of a cross-section of the preform at point C;

[0020] Figure 4D is taken with a microscope Figure 3 of a cross-section of the preform at point D;

[0021] Figure 4E is taken with a microscope Figure 3 of a cross-section of the preform at point E;

[0022] Figure 5 is a photograph of a blow-molded bottle;

[0023] Figure 6A is using at Figure 5 a cross-sectional (x-y) slice generated by micro-CT of a portion near the bottom of the bottle;

[0024] Figure 6B is using atFigure 5 Micro-CT generated cross-sectional (x-y) slices of a portion near the top of the bottle. DETAILED DESCRIPTION

[0025] While the invention is specifically pointed out and distinctly claimed by the claims at the end of the specification, it is believed that the disclosure will be better understood from the following description.

[0026] A striking article having a color gradient can be a blow molded article (such as a container and a bottle) having a hollow body, and can be made via an injection stretch blow molding (ISBM) process. Figure 1 Front view of article 1 (a bottle in this example) having an axial color gradient and a glossy surface.

[0027] The blow molded article can have a wall that defines the hollow body of the article. The wall can include multiple layers formed by ISBM without an adhesive. The wall can include layer A that can be transparent and colored, to 202180008258.4

[0028] and layer B that can contain light-shielding or effect pigments. Article 1 can appear opaque throughout its volume because the wall contains at least one layer having light-shielding pigments and / or effect pigments throughout its volume.

[0029] The axial color gradient can be formed by the ISBM process. In Figure 1 the bottle, the axial color gradient extends from the shoulder 31 to the base 11 on the body 2, and the body 2 can have a glossy outer surface. The glossy outer surface can appear metallic and / or dazzling because the pigments can reside in layer B between layer A. Layer A forms the outer surface of many articles, and layer B can be seen through the transparent layer A, which produces an appearance with glossiness and depth. In Figure 1 , the axial color gradient is a gradual change without an obvious transition point (e.g., a transition line) visible on the outer surface of the article. In this example, the outer surface of the wall is substantially layer A, which is transparent and colored. In some examples, the outer surface can be formed by layer A and layer B, and the outer surface of the wall (excluding the shoulder and the base) can contain at least 80% of layer A, alternatively at least 85% of layer A, alternatively at least 90% of layer A, alternatively at least 95% of layer A, and alternatively at least 97% of layer A. In another example, layer A can be colorless.

[0030] In Figure 1 layer B that can contain effect pigments can generally be located between transparent layer A. In Figure 1 layer B is opaque and contributes to a high opacity on the bottle.

[0031] Interestingly, at the location where layer A tapers, the transition point and / or the bifurcation can vary, even when the preform and the bottle are manufactured according to the same manufacturing process. This results in each bottle looking slightly different and each bottle being unique, which can have an eye-catching and appealing high-quality feel and appearance.

[0032] In another example, layer B containing effect and / or opacifying pigments can generally be the outermost layer of the wall and can form an axial color gradient that can extend over the entire article. In this example, the outer surface of the article is pearlescent, which can have a matte texture and a soft, gentle touch feel. This may be caused by the effect pigments and / or opacifying pigments residing at or near the outer surface of the bottle.

[0033] In another example, the color gradient can extend over a portion of the article.

[0034] The articles made by the blow molding process described herein and each article can be unique. For example, the gradient is generally not the same on any article. This uniqueness contributes to an eye-catching, high-quality article appearance.

[0035] As used herein, "article" refers to a single blow molded hollow object for consumer use, such as a container suitable for holding a composition. Non-limiting examples can include bottles, cans, cups, caps, vials, pour bottles, etc. The article can be used for storage, packaging, transportation / shipping, and / or for dispensing the composition in the container. Non-limiting volumes that can be contained within the container are from about 10 mL to about 1000 mL, from about 100 ml to about 900 mL, from about 200 mL to about 860 mL, from about 260 mL to about 760 mL, from about 280 mL to about 720 mL, from about 350 mL to about 500 mL. Alternatively, the container can have a volume of up to 5 L or up to 20 L.

[0036] The composition contained in the article can be any of a variety of compositions and includes detergents (such as laundry detergents or dish detergents), fabric softeners and scent boosters (such as fabric freshness products), food products (including but not limited to liquid beverages and snacks), paper products (such as facial tissues, wipes), beauty care compositions (such as cosmetics, lotions, shampoos, conditioners, hair styling agents, deodorants and antiperspirants, and personal cleansing products including washing, cleaning, rinsing and / or exfoliating of the skin (including face, hands, scalp and body)), oral care products (such as toothpaste, mouthwash, dental floss), pharmaceuticals (fever reducers, pain relievers, nasal decongestants, antihistamines, cough suppressants, supplements, antidiarrheals, proton pump inhibitors and other heartburn formulations, antiemetics, etc.). The composition can have a variety of forms, non-limiting examples of which can include liquids, gels, powders, beads, solid sticks, packets (such as Tide ) flakes, pastes, tablets, capsules, ointments, filaments, fibers and / or sheets (including paper sheets such as toilet paper, facial tissue paper and wipes).

[0037] The article can be a bottle for containing a product (such as a liquid product such as shampoo and / or conditioner).

[0038] As used herein, the term "blow molding" refers to a manufacturing process for forming a hollow plastic article having a cavity adapted to contain a composition. Generally speaking, there are three main types of blow molding: extrusion blow molding (EBM), injection blow molding (IBM) and injection stretch blow molding (ISBM).

[0039] As used herein, the term "color" includes any color, such as white, black, red, orange, yellow, green, blue, purple, brown and / or any other color, or variations thereof.

[0040] As used herein, the term "color gradient" refers to a colored area having a first region and a second region, wherein the colored area includes any continuous function in the L*a*b* color space. The gradient can be a continuous function of any one or all of the L*, a* and / or b* values relative to the entire sample or the measurement position along the sample.

[0041] As used herein, "effect pigment" means one of two main categories of pigments, "metallic effect pigments" and "special effect pigments". Metallic effect pigments consist only of metal particles. When having parallel alignment in their application system, they produce a metallic-like luster by reflecting light on the surface of the metal flakes. Special effect pigments include all other flaky effect pigments that cannot be classified as "metallic effect pigments". 202180008258.4

[0042] other flaky effect pigments. These pigments are generally based on a substrate having flaky crystals (or particles), such as mica, (natural or synthetic) borosilicate glass, alumina flakes, silica flakes. These flaky particles are usually coated with metal oxides.

[0043] As used herein, "opaque" means that the layer has a total light transmittance of less than 50%. The total light transmittance is measured according to ASTM D1003.

[0044] Special effect pigments can include "pearlescent pigments" (also known as "nacreous pigments"). "Interference pigments" or "pearlescent pigments" based on the use of lamellar substrates such as mica or glass flakes are also suitable, where the lamellar substrates have been coated with one or more dielectric layers including metal oxides, silica, alumina, and other oxides. These pigments can exhibit a pearly luster due to the reflection and refraction of light, and depending on the thickness of the metal oxide layer, they can also exhibit an interference color effect. Non-limiting examples of pearlescent pigments can include mica coated with titanium dioxide, mica coated with iron oxide, and combinations thereof.

[0045] Effect pigments comprising pearlescent pigments are sold as such by suppliers including Merck KGaA, Performance Materials, and BASF.

[0046] As used herein, a "preform" is a unit that has been subjected to preliminary (usually incomplete) shaping or molding and is typically further processed to form an article. Preforms are typically of a generally "test tube" shape.

[0047] As used herein, "substantially free of" means less than 3%, alternatively less than 2%, alternatively less than 1%, alternatively less than 0.5%, alternatively less than 0.25%, alternatively less than 0.1%, alternatively less than 0.05%, alternatively less than 0.01%, alternatively less than 0.001%, and / or alternatively free of. As used herein, "free of" means 0%.

[0048] As used herein, "transparent" means that the layer has a total light transmittance of 50% or greater and a specular haze of less than 5 haze units. The total light transmittance is measured according to ASTM D1003, and the specular haze is measured according to ASTM E430.

[0049] As used herein, the terms "comprising", "including", and "containing" are intended to be non-limiting and are understood to mean "having", "possessing", and "covering", respectively.

[0050] Unless otherwise indicated, all percentages, parts, and ratios are based on the total weight of the compositions of the present invention. All such weights of the listed ingredients are based on the content of the active substance and thus do not include carriers or by-products that may be contained in commercially available substances.

[0051] Unless otherwise specified, all component or composition levels are with respect to the active portion of the component or composition and do not include impurities such as residual solvents or by-products that may be present in commercially available sources of such components or compositions.

[0052] It should be understood that every upper numerical limit given throughout this specification includes every lower numerical limit, as if such lower numerical limits were expressly written herein. Every lower numerical limit given throughout this specification will include every upper numerical limit, as if such upper numerical limits were expressly written herein. Every numerical range given throughout this specification will include every narrower numerical range falling within such broader numerical range, as if such narrower numerical ranges were all expressly written herein.

[0053] In the case of a given content range, these should be understood as the total amount of the component(s) in the composition, or, in the case where more than one substance falls within the range of the component definition, the total amount of all components in the composition conforms to the definition. For example, if a composition contains 1% to 5% fatty alcohol, a composition containing 2% stearyl alcohol and 1% cetyl alcohol and no other fatty alcohols will fall within this range.

[0054] Figure 1 is a front view of article 1 having a color gradient (including an axial color gradient). Article 1 has a body 2 and a neck 4, which has a threaded notch 41 and an orifice 42 on its outer surface, and the orifice is an opening leading to the hollow body of the article. In other examples, the neck can be a lug neck or a snap bead neck bottle mouth. The body has a base 11 at its lower end and a shoulder 31 at its upper end. In Figure 1 the example, the color gradient is visible on and extends along the outer surface of body 2. The color gradient is darker in the area near the shoulder than in the area near the base. The outer surface can be shiny.

[0055] Figure 2 is a cross-sectional view of preform 100 having a color gradient. The preform has a cylindrical body 120 and a cylindrical neck 140. The lower end of the cylindrical body is closed by a hemispherical end cap 111, which has a gate mark 112 at the center of the bottom. The cylindrical neck has a threaded notch 141 on its peripheral wall and a rim-like collar at the boundary between neck 140 and body 120.

[0056] In Figure 2 it, the cross-sectional view also shows a hollow body 125 defined by the wall 150 of the preform. Wall 150 has an inner surface 151 and an outer surface 152. In at least a portion of the neck and body of the preform, wall 150 can have multiple layers. In Figure 2 it, wall 150 has at least two layer A and one layer B (such as 153) on the vast majority of body 120 and neck 140. As Figure 2As seen, layer A forms the vast majority of the inner surface 151 and the outer surface 152. Layer A is thickest near the top / neck of the preform and tapers as it extends the preform body 120 downward toward the end cap 111, creating a color gradient.

[0057] In Figure 2 , layer A is visible on the outer surface to the base in almost its entire extent. However, there remains a portion of the body where layer B includes the outer surface and will include the outer surface of the blow molded article, as Figure 1 shown at the transition point 15. Additionally, the inventors have found that layer A bifurcates at or near the transition point and can alternatively be irregular rather than tapering smoothly and uniformly. Bifurcation can occur due to the manufacturing process where layer A can typically be spliced into additional bifurcations that appear as thin streams in the cross-section of the wall. The bifurcation can only be visible under magnification and in some examples, the bifurcation can be visually perceptible to the observer without magnification.

[0058] In some examples, layer A can extend entirely to the end cap 111. In these examples, the color gradient can extend over the entire length of the article and the entire article can be shiny. Additionally, bifurcations and visual irregularities such as transition points can be at the base and not visible to the consumer when the product is displayed on a store shelf, website, or app.

[0059] In some examples, layers A and B are reversed and layer B forms part of the outer surface and in some examples, forms the outer surface from the neck to the base or near the base. In this example, layer B tapers and forms a color gradient. In this example, the container can be pearlescent rather than shiny. To form the bottle, layers A and B can also be reversed in the preform.

[0060] In yet another example, layer A or B (whichever forms the color gradient) is widest at the base and tapers toward or at the neck, which can result in a final article where the top of the color gradient (e.g., near the shoulder) is brighter than the bottom of the gradient (e.g., near the base).

[0061] The multi-layer structure can be formed by ISBM without (or substantially without) an adhesive.

[0062] Layer B can contain effect pigments and / or opacifying pigments.

[0063] Layer A can be transparent and can contain pigments or soluble dyes. The pigments or dyes can be colored. Alternatively, layer A can be colorless. Layer A can be free or substantially free of pigments and / or particles having a maximum size greater than about 150 nm or between about 150 nm and 5000 nm.

[0064] Alternatively, the A layer may contain pigments, but the A layer may still be transparent because the pigments may be in the matrix, where the difference between the refractive index of the pigments (which depends on the wavelength) and the refractive index of the matrix is small, and Mie scattering occurs when the particle size of the pigments is below this difference (usually the maximum particle size is about 100 nm or less). The A layer may contain opaque absorbing pigments, and the A layer remains transparent if the content of the opaque absorbing pigments in the layer is low enough.

[0065] In the final article, the B layer may contain from about 0.01% to about 10%, alternatively from about 0.5% to about 7.5%, and alternatively from about 1% to about 5% of pigments by weight of the B layer.

[0066] The average wall thickness of the final article may be from about 200 μm to about 5 mm, alternatively from about 250 μm to about 2.5 mm, alternatively from about 300 μm to about 2 mm, alternatively from about 350 μm to about 1.5 mm, and alternatively from about 375 μm to about 1.4 mm. The average wall thickness can be determined using the local wall thickness method described below. The average wall thickness may vary by less than 20%, alternatively less than 15%, alternatively less than 10%, and alternatively less than 10% over the entire volume.

[0067] The average local wall thickness may be substantially uniform over the body of the article, even though the ratio of the B layer thickness to the A layer thickness may vary along the length of the article, and the number of layers and the amount of branching also vary. At a point on the body wall near the neck, the ratio of the A layer thickness to the B layer thickness may be from about 0.4 to about 2.5, and alternatively from about 1 to about 2. At a point on the body wall near the neck, the ratio of the A layer thickness to the B layer thickness may be greater than 1:1, alternatively greater than 3:2, and alternatively greater than 2:1. At the body wall near the base, the ratio of the B layer thickness to the A layer thickness may be from about 2 to about 25, alternatively from about 5 to about 25, alternatively from about 10 to about 25, and alternatively from about 15 to about 25. At the body wall near the base, the ratio of the A layer thickness to the B layer thickness may be less than 1:1, alternatively less than 3:5, and alternatively less than 1:5.

[0068] It has been found that in an article according to the present invention, the effect pigment particles in the B layer can be mainly oriented such that their faces are parallel to the surface of the article. Without being bound by theory, it is believed that the relatively high ratio of oriented to non-oriented flakes may be due to a combination of factors, including the fact that the interface between each stream experiences higher shear compared to a similar location in a single-layer article in which the effect pigment is dispersed throughout the wall of the article, and the wall of the article is thicker than the B layer sandwiched between the A layers (for the same mechanical strength of the article). In a single-layer article, the particles are less concentrated in the high-shear regions, so they have more free space to rotate 360° during the injection molding process, while in a multi-layer article, the B layer is much thinner as it only represents a portion of the total thickness of the article wall, such that the injection molding and stretching steps provide a more optimal orientation of a greater percentage of the flake pigments.

[0069] It has also been found that even when the article is of an irregular shape, the flake effect pigments still tend to remain oriented parallel to the surface of the article. Thus, the shape of the article can also be used to modify the visual effect produced by the article from the perspective of an observer viewing the article, depending on the orientation of the article when being observed.

[0070] The article can have a color gradient that extends along at least a portion of the length of the article and, in some examples, along the entire length of the article. An observer viewing the outer surface of the article can visually perceive the color gradient. The color gradient can extend from a dark intensity to a light intensity, or vice versa.

[0071] In addition or alternatively, the article can include more than one color gradient along the length of the article, for example, a dark-to-light gradient, followed by a light-to-dark gradient, and then another dark-to-light gradient, etc. The color gradient can extend from a first color to a second color. In one example, the color gradient extends from white to a second color, or vice versa. In another example, the color gradient is dark blue and transitions to a lighter blue or cyan color.

[0072] An observer is able to "visually perceive" the color gradient. By "visually perceivable" it is meant that at a distance of 0.25 meters under illumination at least equal to the illumination of a standard 100-watt incandescent light bulb, a human observer can visually resolve the gradient with the naked eye (excluding standard corrective lenses suitable for correcting myopia, hyperopia, or astigmatism, or other vision correction).

[0073] The gradient may include any suitable color, such as white, black, red, orange, yellow, green, blue, purple, brown, silver, gold, and / or any other color, or variants thereof. In certain embodiments, the gradient may be a gradient from blue to white, dark blue to light blue, pink to white, dark pink to light pink, purple to white, dark purple to light purple, red to white, dark red to light red, gold to white, light gold to dark gold, yellow to white, light yellow to dark yellow, green to white, light green to dark green, blue to purple, pink to purple, or any other suitable configuration.

[0074] The color gradient can be identified by the ΔE value along the length or gradient, which is mathematically represented by the following formula:

[0075] ΔE* = [(L* X - L* Y ) 2 + (a* X - a* Y ) 2 + (b* X - b* Y ) 2 1 / 2

[0076] "X" represents the first measurement point along the gradient, and "Y" represents the second measurement point.

[0077] The color scale values used herein to define the gradient are on the CIE LAB scale. Measurements are made using a Hunter color reflectance photometer. A complete technical description of the system can be found in the article by R.S. Hunter, "photoelectric color difference Meter", Journal of the Optical Society of America, Vol. 48, pp. 985 - 995, 1958. Apparatus specifically designed to measure color on the Hunter scale is described in U.S. Patent 3,003,388, issued to Hunter et al. on October 10, 1961. Generally speaking, the Hunter color "L" scale value is a unit of light reflectance measurement, and the higher the value, the lighter the color, because lighter coloring materials reflect more light. Specifically, in the Hunter color system, the "L" scale contains 100 equal division units. Absolute black is at the bottom of the scale (L = 0), and absolute white is at the top of the scale (L = 100). Thus, 202180008258.4

[0078] ​When measuring the Hunter color values of an article according to the present invention, the lower the "L" scale value, the darker the material. The articles herein can be of any color, provided that the L Hunter value as defined herein is satisfied. When defining colors according to this system, L* represents lightness (0 = black, 100 = white), and a* and b* each independently represent two-color axes, where a* represents the red / green axis (+a = red, -a = green), and b* represents the yellow / blue axis (+b = yellow, -b = blue).

[0079] When measurements are made across a color gradient, such as at the top of the gradient, near the center of the gradient, and at the bottom of the gradient, the L*, a*, and b* values will change. In some cases, the values will increase depending on the color, while in other cases, the values will decrease.

[0080] The color gradient can be provided at any suitable location on the article. The color gradient can extend from the base of the article to the shoulder or from the base of the article to the neck. Alternatively, the color gradient can extend only along a portion of the length of the article. Alternatively, a series of color gradients can be provided along the length of the article. Such gradients can be adjacent or separate. Additionally, the color gradient can extend around any suitable amount of the perimeter of the article, such as a portion of the perimeter of the article or substantially the entire circumference of the article.

[0081] The article can appear opaque as visually perceptible by a person. Although the article can appear opaque, the opacity can vary across the bottle as measured by the opacity test method described below.

[0082] The opacity % can be from about 55% to about 100%, alternatively from about 60% to about 98%, and alternatively from about 65% to about 97%. The opacity % can be from about 70% to about 100%, alternatively from about 72% to about 99%, alternatively from about 74% to about 97%, and alternatively from about 80% to about 96%. The opacity % can be greater than 50%, greater than 60%, greater than 70%, greater than 75%, greater than 80%, greater than 85%, and greater than 90%. The opacity is measured according to the opacity test method described below.

[0083] The percent change in opacity from the most opaque region to the most transparent region can be less than 30%, alternatively less than 25%, alternatively less than 22%, and alternatively less than 20%. According to the opacity test method, the opacity can vary across the gradient. Alternatively, the opacity can be substantially the same along the length and / or width of the article.

[0084] The article may have a glossy outer surface. The variation in gloss at 20° over the length and / or width of the outer surface of the body may be substantially the same. The gloss may vary by less than 20 GU, alternatively less than 15 GU, alternatively less than 10 GU, alternatively less than 5 GU, and / or alternatively less than 2 GU over the length and / or width of the outer surface of the body.

[0085] The article may have a location on the outer surface of the body having a gloss at 20° of greater than or equal to 65 GU, greater than or equal to 68 GU, greater than or equal to 70 GU, greater than or equal to 71 GU, greater than or equal to 73 GU, and / or greater than or equal to 75 GU. The article may have a location on the outer surface of the body having a gloss at 20° of from about 65 to about 110 GU, from about 68 GU to about 100 GU, from about 69 to about 95 GU, from about 70 GU to about 90 GU, and / or from 75 GU to about 85 GU.

[0086] Alternatively, the article may have a matte / pearly outer surface, which may have a location on the outer surface of the body having a gloss at 20° of less than or equal to 15, less than or equal to 12, less than or equal to 10, less than or equal to 8, less than or equal to 7, and / or less than or equal to 6. The article may have a matte / pearly outer surface, which may have a location having a gloss at 20° of from about 2 to about 13, from about 4 to about 9, and / or from about 5 to about 8.

[0087] The gloss at 20° may be measured according to the gloss at 20° method described below. The highest GU and the lowest GU may be determined as follows: As described below, a sample panel is removed from the article. The gloss at 20° is measured every 10 mm along the length of the sample panel. The variation is calculated by subtracting the lowest measured value from the highest measured value.

[0088] The article may include a body having an outer surface with surface roughness. The variation in surface roughness over the length and / or width of the outer surface of the body may be substantially the same. The surface roughness may be very less than 20 μin (0.508 μm), alternatively less than 18 μin (0.4572 μm), alternatively less than 10 μin (0.254 μm), alternatively less than 5 μin (0.127 μm), less than 3 μin (0.0762), and / or less than 2 μin (0.0508).

[0089]

[0090] ​The outer surface of the body may have locations with a surface roughness less than 8 μin (0.2032 μm), 5 μin (0.127 μm), less than 3 μin (0.0762), and / or less than 2 μin (0.0508). The outer surface of the article may have locations with a surface roughness of from about 0.5 μin (0.0127 μm) to about 4 μin (0.1016 μm), from about 0.75 μin (0.01905 μm) to about 3.5 μin (0.0889 μm), from about 1 μin (0.0254 μm) to about 3.25 μin (0.08255 μm), from about 1 μin (0.0254 μm) to about 3 μin (0.0762 μm), and / or from about 1.25 μin (0.03175 μm) to about 3 μin (0.0762 μm).

[0091] The outer surface of the body may have locations with a surface roughness greater than 25 μin (0.635 μm), greater than 28 μin (0.7112 μm), greater than 30 μin (0.762 μm), greater than 31 μin (0.7874 μm), and / or greater than 32 μin (0.8128 μm). The outer surface of the article may have locations with a surface roughness of from about 20 μin (0.508 μm) to about 42 μin (1.0668 μm), from about 25 μin (0.635 μm) to about 40 μin (1.016 μm), from about 28 μin (0.7112 μm) to about 38 μin (0.9652 μm), and / or from about 30 μin (0.762 μm) to about 36 μin (0.9144 μm).

[0092] The roughness may be measured according to the surface roughness measurement method described below. The highest surface roughness and the lowest surface roughness may be determined as follows: As described below, the sample panel is removed from the article. The surface roughness is measured every 10 mm along the length of the sample panel. The variation is calculated by subtracting the lowest measured value from the highest measured value.

[0093] In addition, compared to other articles (including single-layer and multi-layer articles), the articles described herein are less prone to delamination. Delamination is a common problem in the manufacture of blow-molded multi-layer hollow articles such as bottles and containers. Delamination can occur immediately or over time due to thermal or mechanical stresses caused by mechanical handling of the container. It typically manifests as bubbles on the surface of the container (which are actually separations of two layers at the interface visible through the bubble-like appearance), but can also be at the source of container damage. Without being bound by theory, we believe that parallel flow co-injection results in the formation of a bonding region between the layers where the layers slightly interpenetrate due to the long-term contact of the layer materials that are still in a molten or partially molten state. The bonding region creates good adhesion between the layers, thus making it more difficult to separate them. Surprisingly, it has also been found that the multi-layer articles according to the present invention have improved delamination resistance not only compared to articles obtained from preforms made by blow molding using step flow co-injection or overmolding, but even compared to articles obtained from single-layer preforms. In other words, the interface layer appears to further strengthen the article wall relative to single-layer implementation. As described below, delamination resistance is evaluated by measuring the critical nominal load. A higher critical nominal load indicates higher delamination resistance.

[0094] The article can have a critical nominal load greater than or equal to 90 N, greater than or equal to 95 N, greater than or equal to 100 N, greater than or equal to 104 N, greater than or equal to 105 N, greater than or equal to 110 N, and / or greater than or equal to 120 N. The article can have a critical nominal load of about 90 N to about 170 N, alternatively about 95 N to about 160 N, alternatively about 100 N to about 155 N, and alternatively about 104 N to about 145 N. The critical nominal load can be measured by critical nominal load using the method described below.

[0095] In one example, both layer A and layer B contain PET and can have a critical nominal load greater than 100 N. However, PET / PEN, PET / COC (cycloolefin copolymer), PET / nylon, PET / recycled PET, or PET / LCP can have a lower nominal load. For example, the nominal load of these embodiments can be greater than 20 N, greater than 30 N, and / or greater than 40 N. Alternatively, the nominal load of these embodiments can be about 10 N to about 110 N, about 20 N to about 80 N, about 30 N to about 70 N, and alternatively about 40 N to about 60 N.

[0096] Using the method described below, delamination resistance is evaluated by measuring the critical nominal load. A higher critical nominal load indicates higher delamination resistance.

[0097] The articles and preforms according to the present invention are typically made of thermoplastic materials, usually including thermoplastic resins.

[0098] The article may contain more than 50% by weight, preferably more than 70% by weight, more preferably more than 80% by weight, and even more preferably more than 90% by weight of a thermoplastic resin selected from the group consisting of: polyethylene terephthalate (PET), ethylene glycol-modified polyethylene terephthalate (PETG), polystyrene (PS), polycarbonate (PC), polyvinyl chloride (PVC), polyethylene naphthalate (PEN), poly(1,4-cyclohexanedimethylene terephthalate) (PCT), diol-modified PCT copolymer (PCTG), copolyester of cyclohexanedimethanol and terephthalic acid (PCTA), polybutylene terephthalate (PBCT), acrylonitrile-styrene (AS), styrene-butadiene copolymer (SBC), or a polyolefin (such as low-density polyethylene (LDPE), linear low-density polyethylene (LLPDE), high-density polyethylene (HDPE), polypropylene (PP), polymethylpentene (PMP), liquid crystal polymer (LCP), cycloolefin copolymer (COC)), and combinations thereof. The thermoplastic resin is selected from the group consisting of: PET, HDPE, LDPE, PP, PVC, PETG, PEN, PS, and combinations thereof. In one example, the thermoplastic resin may be PET.

[0099] Recycled thermoplastic materials may also be used, such as post-consumer recycled polyethylene terephthalate (PCRPET); post-industrial recycled polyethylene terephthalate (PIRPET); re-ground polyethylene terephthalate.

[0100] The thermoplastic materials described herein may be formed by using a combination of monomers derived from renewable resources and monomers derived from non-renewable (e.g., petroleum) resources. For example, the thermoplastic resin may comprise a polymer made entirely from bio-derived monomers, or a polymer made partially from bio-derived monomers and partially from petroleum-derived monomers.

[0101] The thermoplastic resins used herein may have a relatively narrow weight distribution, such as metallocene PE polymerized using a metallocene catalyst. These materials may improve gloss, such that in embodiments of metallocene thermoplastic materials, the articles formed have further improved gloss. However, metallocene thermoplastic materials may be more expensive than commodity materials. Thus, in an alternative embodiment, the article is substantially free of expensive metallocene thermoplastic materials.

[0102] Layer A and layer B may be based on the same type of thermoplastic resin (such as PET), which may allow the layers to better penetrate each other at the interface and have a stronger wall due to their chemical compatibility. "Based on phase 202180008258.4

[0103] "Resins of the same type" means that layer A and layer B may contain at least 50%, at least 70%, at least 90% and / or at least 95% of the same type of resin. Resins of the "same type" are intended to be resins belonging to the same chemical category, i.e., PET is considered a single chemical category. For example, two different PET resins with different molecular weights are considered to be of the same type. However, a PET resin and a PP resin are not considered to be of the same type. Nor are different polyesters considered to be of the same type.

[0104] Layer A and layer B may be formed of the same thermoplastic resin (e.g., PET), and may differ only in the types of colorants and pigments added (including effect pigments and / or coloring pigments).

[0105] The article may include one or more sub-layers having various functions. For example, the article may have a barrier material sub-layer or a recyclable material sub-layer between an outer layer of thermoplastic material and an inner layer of thermoplastic material. Such a layered container can be made from a multi-layer preform according to common techniques employed in the field of thermoplastic manufacturing. Since the barrier material sub-layer and the recyclable material sub-layer can be used in layer A (especially when they do not affect the transparency of layer A) or layer B or an additional layer C.

[0106] The article may contain (as long as the required properties of the layer are maintained) amounts of additives that are generally from about 0.0001% to about 9%, from about 0.001% to about 5% and / or from about 0.01% to about 1% by weight of the article in any one of its layers. Non-limiting examples of additives may include: fillers, curing agents, antistatic agents, lubricants, UV stabilizers, antioxidants, antiblocking agents, catalytic stabilizers, nucleating agents and combinations thereof.

[0107] Additional gradients and / or visual effects can be produced. For example, layer A or layer B may contain black or colored absorbing pigments.

[0108] Layer A may also contain effect pigments, including effect pigments that are small enough and / or in small enough amounts so that layer A still appears transparent or partially transparent. For example, layer A may contain a relatively small content of effect pigments with small particle sizes or even a smaller content of effect pigments with large particles (e.g., to produce a glitter effect).

[0109] Layer B may contain light-shielding pigments (in addition to or instead of effect pigments). Light-shielding pigments may include light-shielding agents, opaque absorbing pigments, and combinations thereof.

[0110] Non-limiting examples of light blockers can include titanium dioxide, calcium carbonate, silica, mica, clay, minerals, and combinations thereof. The light blocker can be any domain / particle having a refractive index appropriately different from that of the thermoplastic material (e.g., PET, which can include poly(methyl methacrylate), siloxane, liquid crystal polymer (LCP), polymethylpentene (PMP), air, gas, etc.). Additionally, the light blocker can have an appearance that is white due to light scattering or black due to light absorption and intermediate tones therebetween, as long as they prevent most light from transmitting into the underlying layer. Non-limiting examples of black light-blocking pigments include carbon black and organic black pigments such as Black L 0086 (BASF).

[0111] Opaque absorbing pigments can include particles that provide color and opacity to the material in which they are present. The opaque absorbing pigments can be inorganic or organic particulate materials. All absorbing pigments can be opaque if their average particle size is large enough (generally greater than 100 nm, alternatively greater than 500 nm, alternatively greater than 1 micron, and alternatively greater than 5 microns). The absorbing pigments can be organic pigments and / or inorganic pigments. Non-limiting examples of organic absorbing pigments can include azo and diazo pigments such as azo and diazo lakes, Hansa, benzimidazolone, diaryl, pyrazolone, pigment yellow and red; polycyclic pigments such as phthalocyanine, quinacridone, perylene, naphthalenone, dioxazine, anthraquinone, isoindoline, thioindigo, diaryl or quinoline yellow pigments, aniline black, and combinations thereof. Non-limiting examples of inorganic pigments can include titanium yellow, iron oxide, ultramarine blue, cobalt blue, chromium oxide green, lead yellow, cadmium yellow and cadmium red, carbon black pigments, and combinations thereof. The organic pigments and inorganic pigments can be used alone or in combination.

[0112] Controlling the layer arrangement and components in the A layer and the B layer can help to create unique color characteristics and transparency to achieve different visual effects, ultimately resulting in an eye-catching high-quality appearance. For example, the A layer can be transparent and colored, and the B layer can have a silver pearlescent effect pigment, which can result in a gradient between a matte silver pearlescent appearance and a glossy colored pearlescent. Alternatively, the A layer can be opaque and black, and in combination with the B layer having an effect pigment that produces an interference color, a gradient blow molded article having a gradient from black to a strong interference color can be achieved.

[0113] The A layer and the B layer can contain similar resins, such as the same grade of PET, different grades of PET, or virgin PET / recycled PET (rPET). The A layer and the B layer can also contain different resins that can be alternated within the article, such as PET / cyclic olefin copolymer, PET / PEN, or PET / LCP. The resin pair is selected to have optimal properties, such as appearance, mechanics, and gas barrier and / or moisture barrier.

[0114] Articles can be manufactured according to the ISBM process described herein. Articles manufactured using the ISBM process (and their respective preforms manufactured by injection molding) can be distinguished from similar articles manufactured using different processes such as extrusion blow molding by the presence of gate marks, i.e., small bumps, that indicate the "gate" where injection occurred. Typically, in the case of containers and bottles, the "gate marks" are present at the bottom of the article.

[0115] The ISBM process starts with the manufacture of the preform. In ISBM, the preform can be made by co-injection molding. Here, when the material of the outer layer flows into the mold cavity, the material near the core and the cavity wall solidifies and the material continues to flow downward along the central channel. When the material of stream a (which contains a transparent and / or translucent material in a thermoplastic resin) enters, it has a flow rate that exceeds that of stream b (which forms an opaque B layer), causing stream a to push past the initial flow front. This stream a now causes an injection process, whereby it becomes the new outer layer in the same mold cavity and, as it flows forward, the injection filling rate (speed) increases, allowing it to gradually thicken and continue to solidify on the wall, thus producing the outer layer. This effectively forms a preform with two different streams solidified at the outer surface. The preform has a wall that has a different number of layers depending on the processing conditions and the material forming the outer layer.

[0116] Here, the unique visual appearance of the article can be achieved by significantly modifying the above standard method, and the preform can be manufactured as follows: First, the preform can be manufactured using the parallel flow co-injection method, where the injection of the streams starts within 5 seconds of each other.

[0117] The injection of the material streams typically occurs as follows: The initial injection of stream a (containing the molten A layer) starts almost simultaneously and / or simultaneously with the injection of stream b (containing the molten B layer). If there is a delay, the delay can be about 0.01 - 2 seconds. In some examples, stream a will start before and / or almost simultaneously with stream b. At the desired time and after inserting the streams into the preform mold, stream a is accelerated to a flow rate faster than that of stream b. This causes stream a to blow through stream b and causes stream a to flow to the outside of stream b. Thus, stream a gradually forms the outer surface of the preform, bringing the A layer material to the outside of the part and creating a color gradient. The resulting appearance depends on the material flowing in stream a.

[0118]

[0119] ​Forking may occur in layer A and / or layer B. These forks are attributed to the formation of spiral flows, which are formed by the material flow when the material flow advances in a viscous environment. These flows do not follow the typical spiral undulations seen in typical fluids. The method is characterized in that the elongation of the fluid material forms thin spiral regions between the larger nodules of the viscous fluid. These spiral regions will generally continue to thin until they break, thus forming separate fluid droplets.

[0120] An example of forking is a single flow of material flow a, which tapers (becomes thinner) along the axial direction of the article and may split to form multiple flows mainly composed of material flow b. Similarly, the flow of material flow b can taper in a manner opposite to that of material flow a, and this flow can split into multiple flows. The ability to fork either or both of material flows a and b can control the appearance and surface roughness of the article in a gradual manner.

[0121] The required time can be controlled according to the desired visual effect. Of course, the operator can choose to start with guiding material flow a at the beginning and later accelerate material flow b to obtain different visual effects. In any case, the timing of the material flow acceleration will determine the visual effect, that is, whether the neck, base or body of the article or its part will have pigment on the outer surface.

[0122] It has been found that during the production of the preform for the present invention, strict temperature control can be beneficial to the regularity of each layer, which is achieved partly by affecting the viscosity of the thermoplastic material. The material for material flow b (containing the molten B layer) can be injected at a temperature similar to that of the material for material flow a (containing the molten A layer). The preferred temperature range for the material for material flow a (containing the molten A layer) is between about 240 °C and about 305 °C, alternatively about 250 °C to about 300 °C, alternatively about 270 °C to about 290 °C, alternatively about 275 °C to about 285 °C, and / or about 280 °C, measured at the injection point. The material for material flow B (containing the molten B layer) can be at a temperature in the range of about 260 °C to about 310 °C, alternatively about 270 °C to about 300 °C, alternatively about 275 °C to about 285 °C, alternatively greater than or equal to about 280 °C, measured at the injection point. The temperature of material flow b can be higher than that of material flow a. The temperature can vary according to the thermoplastic resin and the pigment loading of the material flow. Lower temperatures and higher viscosity material flows contribute to better and more uniform layer formation. Good monitoring and adjustment of the difference in material flow viscosities are required to prevent deformed layers or abnormalities in the flow, which may affect the integrity of the final article.

[0123] Another process parameter that must be controlled during the co-injection process for manufacturing the preform is the pressure of the material flow measured along the manifold line supplying the injection nozzle. The material flow a (which forms layer A) is preferably maintained within a range between about 25 bar and about 400 bar, alternatively between about 30 bar and about 40 bar, alternatively between about 34 bar and about 36 bar, while the lower temperature / higher viscosity material flow b (which forms layer B) is preferably maintained within a range between about 1000 bar and about 1600 bar.

[0124] To maintain the transparency of layer A, it is beneficial to rapidly cool the preform as soon as it is formed. The same applies to the rapid cooling of the article after it is formed by the stretch blow molding operation. Prolonged exposure at a temperature close to the glass transition temperature (Tg) of the resin can promote resin crystallization, which in turn may be detrimental to transparency. Rapid cooling maintains an amorphous and transparent structure as much as possible.

[0125] When the preform is subsequently released from the preform mold, it can be immediately processed, but more typically it is cooled, stored, and processed at a subsequent time and / or location at a stretch blow molding station. In the second step, the preform is introduced into a stretch blow molding apparatus where, typically using a mandrel, the preform is blown into its final shape by heating and stretching. In the ISBM process, unlike other blow molding processes, the preform is reheated to a sufficiently warm temperature to allow the preform to expand, thereby achieving biaxial molecular alignment in the sidewalls of the resulting blow molded container. While holding the preform at the neck, air pressure and usually a stretching rod are used to stretch the preform axially and optionally also radially. In the case of a bottle, the neck portion of the article can include threads or flanges suitable for closures and, since the neck portion is generally not stretched, it generally does not change relative to the preform. Articles obtained by injection stretch blow molding can be significantly longer than the preform. More information on the injection stretch blow molding process can be obtained from general textbooks such as “The Wiley Encyclopedia of Packaging Technology” published by Wiley-Interscience Publication, 2nd Edition (1997) (specifically see pages 87 - 89).

[0126] These steps can have many variations, for example the preform can be stretch molded and blown within the same machine that manufactures the preform, but the two-step / two-machine process is more common.

[0127] Multi-layer articles can be manufactured by blow molding co-injected preforms, where the preform can be manufactured via parallel flow co-injection.

[0128] Embodiment

[0129] Figure 3It is a photograph of a cross-section of a preform taken with a stereomicroscope. Figure 3 It shows how the thickness and ratio of layer A to layer B vary over the preform. Figure 3 Respectively having points A, B, C, D, and E corresponding to Figure 4A , B, C, D, and E. Figure 4A -E are photographs of the preform taken with a stereomicroscope Figure 3 at points A - E. Figure 4A -E shows how the thickness and ratio of layer A to layer B vary at each point.

[0130] Figure 4A is at the neck of the preform, which will eventually become the bottleneck, and two layer A's and one layer B are distinguishable. At Figure 4A , the ratio of layer A to layer B is greater than 2:1. At Figure 4B , two layer A's and one layer B are distinguishable. At Figure 4B , the ratio of layer A to layer B is greater than 3:2. At Figure 4C -E, layer B is significantly wider than either layer A. At Figure 4C , the ratio of layer A to layer B is less than 1:1. At Figure 4D , the ratio of layer A to layer B is less than 3:5. At Figure 4E , layer A appears very thin, and the ratio of layer A to layer B is less than 1:5.

[0131] Figure 5 is a blow - molded bottle with a color gradient. As described in the micro - CT test method as presented herein, boxes 501 and 502 represent the parts cut via micro - CT.

[0132] Figure 6A is a cross - sectional slice in the x - y plane of the micro - CT voxel data of part 501 from Figure 5 , facing the bottom of the bottle. In Figure 6A , layer B 553 is almost the entire wall in this part. Layer A 552 forms the outer surface of the wall and layer A 551 forms the inner surface of the wall, and both are represented as very thin regions in this image.

[0133] Figure 6B is a cross - sectional slice in the x - y plane of the micro - CT voxel data of part 502 from Figure 5 , facing the top of the bottle. In Figure 6B , layer A 551 and 552 and layer B 553 are visible. Compared with the image in Figure 6A , layer B 553 in Figure 6B is narrower, and layer A 551 and 552 are wider.

[0134] Testing method

[0135] When the article is a container or bottle, the critical nominal load, gloss at 20°, opacity, and spectrophotometric measurements are made on a sample panel removed from the article. A sample having dimensions of 100 mm in length and approximately 50 mm in width is cut from the main portion of the article wall and at least 50 mm away from the shoulder / neck and base regions.

[0136] When the article does not permit removal of such a large sample, a shorter sample with a width:length ratio of 1:2 may be used, as further detailed below. For containers and bottles, the sample is preferably removed from the labeling panel of the bottle at least 50 mm away from the shoulder / neck or base region. Cutting is performed with a suitable razor blade or utility knife to remove a larger area, and then it is further cut to the appropriate size with a new single-edge razor blade.

[0137] If possible, the sample should be flat, or made flat by using a frame that keeps the sample flat at least in the area where the tests are performed. The sample being flat is important for determining the critical nominal load, gloss at 20°, profilometry, opacity, and spectrophotometry.

[0138] Critical nominal load (N) and scratch depth at the damaged area

[0139] If the sample is prone to delamination when removed from the bottle, a score of 0 N is given to the sample for the "critical nominal load". For samples that remain intact, they are subjected to damage caused by scratching according to the scratch test procedure (ASTM D7027-13 / ISO 19252:08) using a Scratch 5 purchased from Surface Machine Systems, LLC with the following settings: 1 mm diameter spherical tip, initial load: 1 N, end load: 125 N, scratch rate: 10 mm / s, and scratch length 100 mm. For samples less than 100 mm, the scratch length may be reduced while keeping the initial and end loads the same. This provides an estimate of the critical nominal load. Using this estimate, additional samples can be run in a narrower load range to more accurately determine the critical nominal load.

[0140] Damage caused by scratching is performed on both sides of the sample corresponding to the inner and outer surfaces of the bottle. It is crucial to adhere the sample to the sample stage using a foam-type double-sided tape (such as the permanent mounting tape) (a polyurethane double-sided high-density foam tape with an acrylic adhesive, having a total thickness of approximately 62 mils or 1.6 mm, UPC#021200013393) on the underside of the sample. All samples are cleaned with compressed air prior to the scratch test.

[0141] After completion of the scratch test, the damage point is visually determined as the distance along the scratch length at which visible delamination starts to occur. Delamination introduces a visible air gap between the layers, visible to the naked eye or to a person skilled in the art with the aid of a stereomicroscope. This is verified based on three minimum scratches (defined as incisions in the upper bottle) with a standard deviation of 10% or less on each side of the sample. The side with the lower critical nominal load is recorded as the result of the method. At the scratch location where delamination starts to occur, the scratch depth at the damaged area is measured according to ASTM D7027. The critical nominal load (N) is defined as the nominal load recorded at the location determined to be the damage point. A laser scanning confocal microscope (KEYENCE VK-9700K) and VK-X200 analyzer software are used to analyze the damage caused by the scratch, including the damage point, scratch width, and scratch depth.

[0142] Gloss 20° method

[0143] Gloss at 20° is measured with a glossmeter under a 20° mini-triangle glossmeter (BYK-Gardner GmbH) according to ASTM D 2457 / D523. Each point is measured three times and the average is calculated to determine the gloss at 20°. All gloss measurements are made on a black background, which is referred to as "base black". Base black is the black area in an X-Rite gray balance card (45as45 L*a*b* 21.07 70.15 -0.29). The measurements provided by the mini-triangle glossmeter have the unit "GU" representing "gloss units".

[0144] Local wall thickness

[0145] Using a 1 / 8” diameter target ball, an Olympus 8600 is used to measure the wall thickness at specific locations. Three measurements are made at each location and their average is calculated to determine the local wall thickness.

[0146] The average local wall thickness is taken over the length of the article or panel and then the average is calculated. The thicknesses near the shoulder and near the base are excluded from the average local wall thickness.

[0147] Surface roughness measurement method

[0148] Method 1: Using a portable surface roughness tester such as a Surftest SJ-210 (Mitutoyo America Corporation), it is placed at an equal height on the bottle to analyze the Ra (arithmetic mean height) of the sample panel. Roughness is measured in μin.

[0149] Opacity test method

[0150] Measure the opacity on the cut portion of the bottle using a portable densitometer with a 3 mm diameter hole, such as the X-rite 341C (X-Rite, Inc.). Measure the absolute optical density (D), and then convert it to transmittance (T) through D = -log 10 T, where the opacity % is 100 - %T. An optical density (D) of 5.00 = 100% opaque, and 0.00 = 0% opacity. Measure each point three times and calculate the average value to determine the opacity %.

[0151] Micro-CT method

[0152] Image the bottle sample to be tested into a single data set with continuous voxels using a micro-CT X-ray scanner capable of scanning samples with dimensions of approximately 5 mm × 5 mm × 3 mm. An isotropic spatial resolution of 2 μm is required in the data set collected by the micro-CT scan. An example of a suitable instrument is the SCANCO Systems model μ50 micro-CT scanner (Scanco Medical AG, Brüttisellen, Switzerland), which operates at the following settings: 55 kVp energy level at 72 μA; 3600 projections; 10 mm field of view; 700 ms integration time; an average of 5; and a voxel size of 2 μm. Prepare the test sample to be analyzed as follows: Use a knife to cut a rectangular plastic sheet from the wall, preferably from a flat area such as the label panel area, and then use a fine-tooth saw to further trim the sample to a width of approximately 5 mm, being careful not to cause cracks. Position the sample perpendicular to the mounting foam material and place it in a plastic cylindrical scanning tube and secure it inside the micro-CT scanner. Select the image acquisition settings of the instrument such that the image intensity contrast is sensitive enough to provide a clear and reproducible distinction between multiple layers within the material and the material itself and the external environment (including air and mounting foam). Image acquisition settings that cannot achieve this contrast distinction or the required spatial resolution are not applicable to this method. Capture the scan of the plastic sample such that each sample of a similar volume with its thickness is included in the data set. The software for reconstructing the data set to generate a 3D rendering is supplied by the scanner manufacturer. Software suitable for subsequent image processing steps and quantitative image analysis includes programs such as Avizo Lite 2019.1 (Visualization Sciences Group / FEI Company, Burlington, Massachusetts, U.S.A.), and MATLAB R2020b version with the corresponding MATLAB Image Processing Toolbox (The Mathworks Inc., Natick, Massachusetts, U.S.A.).

[0153] Micro-CT data collected with a 16-bit grayscale intensity depth is converted to an 8-bit grayscale intensity depth, taking care to ensure that the resulting 8-bit data set maintains the maximum dynamic range and the smallest number of saturated voxels feasible, while excluding extreme outliers.

[0154] A square cross-section of the sample is cropped from the micro-CT voxel data to approximately 2 mm × 2 mm, thus selecting a defect-free and nearly planar region. The sample is then aligned using resampling to be parallel to the YZ plane of the global axis system. In other words, the normal to the bottle wall surface is parallel to the X plane / axis. This is achieved by first using thresholding and connected component labeling of the plastic voxels in the micro-CT data. The centers of the labeled voxels create a point cloud that can be fit to a plane using least squares regression. Image processing that fails to find the least squares plane that is nearly parallel to the largest face of the rectangular plastic volume is not suitable for this method. The fitted plane is used to rotate and resample the voxel points into a suitable orientation.

[0155] An analysis is performed on the aligned 8-bit data set that contains a rectangular cross-section of the material that is approximately 2 mm × 2 mm from boundary to boundary in the YZ direction. It intersects exactly with the minimum Y boundary, the maximum Y boundary, the minimum Z boundary, and the maximum Z boundary. Small non-material buffer regions will exist between the minimum X boundary and the maximum X boundary. This region will consist of air or a filler material. The global material threshold of the sample is determined by the Otsu method implemented in Matlab. This material threshold should identify the bottle material while minimizing noise and filler material.

[0156] YZ slices of the voxel data are taken along the X-axis. Each YZ slice can be considered an almost uniform image that will contain air (fill) or a single layer of material. As the X value travels between regions, a small number of images will show transitions. The average voxel intensity of each slice is plotted along the X-axis at a resolution of 2 μm (the resolution of the micro-CT scan). This plot of the average YZ slice intensity will be called the YZ average plot. The YZ average plot will have a low intensity through the air portion of the sample until it approaches the edge of the material. As it approaches the edge, it will cross the global material threshold and then achieve a local peak at the material edge due to "diffraction artifacts" from the micro-CT scan. The X position of this peak will be recorded as the starting X position of the sample material. The starting X position on the opposite side of the sample can be found in a similar manner.

[0157] Now, the X value is moved from the material starting position to a point inside the sample and away from the "diffraction artifacts". The first local intensity minimum after the "diffraction peak" on the YZ average plot will meet this requirement. The data set is trimmed along the X-axis such that all voxel points are inside the sample but outside the "diffraction effect". The global pigment threshold can be determined from this subset of the data set that contains only plastic by performing the Otsu method.

[0158] Move the X values within the sample on either side of the plastic towards the center. The two moved X values will display the intensity of the YZ average curve graph that crosses the global pigment threshold. These crossed X values are recorded as the starting pigment edge positions on the corresponding sides of the sample. Calculate the distance measurement results from the above-recorded X positions.

[0159] Combination

[0160] A. A blow-molded multi-layer article, comprising:

[0161] A hollow body defined by a wall including an inner surface and an outer surface;

[0162] And a neck extending from the body to an orifice;

[0163] Wherein at least a first part of the wall comprises at least three layers, and the at least three layers include:

[0164] Two A layers forming the outer surface and the inner surface of the wall and a B layer located between the A layers;

[0165] Wherein the A layer is transparent and optionally contains a coloring dye or pigment;

[0166] Wherein the B layer contains an effect pigment and / or a light-shielding pigment;

[0167] Wherein the A layer and the B layer contain a thermoplastic resin;

[0168] Wherein the thickness of the A layer varies;

[0169] Wherein the outer surface has an axial color gradient formed by the components of the A layer that form the outer surface.

[0170] B. The article according to paragraph A, wherein the effect pigment or the light-shielding pigment is visible through the A layer.

[0171] C. The article according to paragraphs A - B, wherein the B layer extends over the entire length of the article wall, and wherein the B layer has a variable thickness.

[0172] D. The article according to paragraphs A - C, wherein the hollow article further includes a neck and a base, and the B layer has a thinner width at the neck compared to the width of the B layer at the base.

[0173] E. The article according to paragraphs A - D, wherein the B layer bifurcates and / or the A layer bifurcates.

[0174] F. An article according to paragraphs AE, wherein the outer surface of the body also has a surface roughness, and wherein the surface roughness is substantially the same on the outer surface, and wherein the surface roughness varies on the outer surface by less than 20 μin (0.508 μm), preferably less than 18 μin (0.4572 μm), alternatively less than 10 μin (0.254 μm), more preferably less than 5 μin (0.127 μm), and even more preferably less than 3 μin (0.0762).

[0175] G. An article according to paragraphs AF, wherein the surface roughness of a portion of the outer surface is less than 8 μin (0.2032 μm), preferably 5 μin (0.127 μm), more preferably less than 3 μin (0.0762), and even more preferably less than 2 μin (0.0508 μm).

[0176] H. An article according to paragraphs AG, wherein a portion of the outer surface has a surface roughness of about 20 μin (0.508 μm) to about 42 μin (1.0668 μm), preferably about 25 μin (0.635 μm) to about 40 μin (1.016 μm), more preferably about 28 μin (0.7112 μm) to about 38 μin (0.9652 μm), and even more preferably about

[0177] 30μin (0.762μm) to about 36μin (0.9144μm).

[0178] I. An article according to paragraphs AG, wherein the outer surface of the body further has a gloss of 20°, and wherein the surface roughness is substantially the same over the length and / or width of the outer surface, and wherein the gloss 20° is along the 202180008258.4 of the body.

[0179] The length and / or width of the outer surface varies by less than 15 GU, preferably less than 10 GU, more preferably less than 5 GU, and even more preferably less than 2 GU.

[0180] J. An article according to paragraph AI, wherein the outer surface of the body is glossy and has a gloss 20° of about 65 to about 110 GU, preferably about 68 GU to about 100 GU, more preferably about 69 to about 95 GU, and even more preferably about 70 GU to about 90 GU.

[0181] K. The article according to paragraphs A-J, wherein the outer surface of the body is shiny, including positions where the gloss at 20° is less than or equal to 15, preferably less than or equal to 12, more preferably less than or equal to 10, and even more preferably less than or equal to 7.

[0182] L. The article according to paragraphs A-K, wherein the article has an opacity of about 70% to about 100%, preferably about 75% to about 95%, and more preferably about 80% to about 93%.

[0183] M. The article according to paragraphs A-L, wherein the opacity % can be greater than 70%, preferably greater than 75%, more preferably greater than 80%, and even more preferably greater than 85%.

[0184] N. The article according to paragraphs L-M, wherein the change in opacity over the length of the article is less than 30%, preferably less than 25%, more preferably less than 22%, and even more preferably less than 20%.

[0185] O. The article according to paragraphs A-N, wherein the neck is defined by the wall having an inner surface and an outer surface;

[0186] wherein the neck does not have a color gradient;

[0187] and wherein a part of the outer surface of the neck comprises layer A, and wherein a part of the outer surface of the neck comprises layer B.

[0188] P. The article according to paragraphs A-O, wherein the article has a critical nominal load greater than 100 N, preferably greater than 105, and more preferably greater than 110.

[0189] Q. The article according to paragraphs A-P, wherein the effect pigment is a pearlescent pigment, and wherein the effect pigment accounts for about 0.01% to about 10% by weight of the layer B.

[0190] R. The article according to paragraphs A-Q, wherein the wall has a thickness of about 250 μm to about 1 mm, preferably about 300 μm to about 700 μm, more preferably about 400 μm to about 600 μm, and even more preferably about 450 μm to about 575 μm, and the average thickness of the wall panel varies by less than 30% over the length of the article.

[0191] S. An article according to paragraphs A - R, wherein the thermoplastic resin is selected from the group consisting of: polyethylene terephthalate (PET), ethylene glycol - modified polyethylene terephthalate (PETG), polystyrene (PS), polycarbonate (PC), polyvinyl chloride (PVC), polyethylene naphthalate (PEN), polycyclohexylene dimethylene terephthalate (PCT), glycol - modified PCT copolymer (PCTG), copolyester of cyclohexanedimethanol and terephthalic acid (PCTA), polybutylene terephthalate (PBCT), acrylonitrile - styrene (AS), styrene - butadiene copolymer (SBC), low - density polyethylene (LDPE), linear low - density polyethylene (LLPDE), high - density polyethylene (HDPE), polypropylene (PP), and combinations thereof.

[0192] T. An article according to paragraph S, wherein the multi - layer article comprises polyethylene terephthalate.

[0193] U. An article according to paragraphs A - T, wherein the article has a non - cylindrical shape.

[0194] V. A method of manufacturing a blow - molded article, comprising the steps of:

[0195] a. Providing a pre - forming mold for manufacturing a pre - form;

[0196] b. Injecting a stream b comprising molten thermoplastic resin and effect pigment and / or opacifying pigment into the pre - forming mold at a flow rate b;

[0197] c. Simultaneously or within 0.01 - 2 seconds of injecting stream b, injecting a stream a comprising molten thermoplastic resin into the pre - forming mold at an initial flow rate a;

[0198] d. Accelerating the flow rate a to be faster than the flow rate b;

[0199] e. Stream a blowing through stream b and flowing towards the outside of stream b;

[0200] f. Cooling to form a pre - form including an outer surface, wherein at least a portion of the outer surface comprises solidified stream a, and the solidified stream a creates a color gradient;

[0201] g. Blow - molding the pre - form to form an article according to paragraphs A - U.

[0202] The dimensions and values disclosed herein should not be construed as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to represent the recited value and a range functionally equivalent around that value. For example, a dimension disclosed as "40 mm" is intended to represent "about 40 mm".

[0203] Unless expressly excluded or otherwise limited, each document cited in this application, including any cross-references or related patents or patent applications and any patent application or patent to which this application claims priority or the benefit of which, is hereby incorporated by reference in its entirety. The citation of any document is not an admission that it is prior art with respect to any invention disclosed in this application or claimed in the claims hereof, or that it alone or in any combination with any one or more other references, teaches, suggests or discloses any such invention. Further, when any meaning or definition of a term in this application conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to the term in this application shall govern. 202180008258.4

[0204] Existing technology recognition, or an admission that it alone or in combination with any one or more other references, makes, suggests or discloses any such invention. Further, when any meaning or definition of a term in this application conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to the term in this application shall govern.

[0205] While specific embodiments of the invention have been illustrated and described, it will be apparent to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is intended that all such changes and modifications that fall within the scope of the invention be covered by the appended claims.

Claims

1. A blow-molded multi-layer article, comprising: A hollow body extending from a bottom to a neck, the neck extending from the hollow body to an orifice, the hollow body and the neck being defined by a wall having an inner surface and an outer surface; wherein at least a first part of the wall comprises at least three layers, the at least three layers comprising: at least two A-layers forming the outer and inner surfaces of the wall and at least one B-layer located between the A-layers, the A-layers and the B-layer comprising the same type of thermoplastic resin to allow the A-layers and the B-layer to interpenetrate at the interface; wherein the A-layers are transparent and comprise a coloring dye or pigment; wherein the B-layer comprises effect pigments and / or light-shielding pigments; wherein the thickness of the A-layer forming the outer surface varies from the neck to the bottom; wherein the outer surface has an axial color gradient extending along the entire length of the article, the axial color gradient being formed by the components of the A-layer forming the outer surface; At a point on the body wall near the neck, the ratio of the thickness of the A-layer to the thickness of the B-layer is from 1 to 2, and at the body wall near the base, the ratio of the thickness of the B-layer to the thickness of the A-layer is from 2 to 25.

2. The blow-molded multi-layer article according to claim 1, wherein the B layer extends over the entire length of the article wall, and wherein the B layer has a variable thickness.

3. The blow-molded multi-layer article according to claim 1, wherein the outer surface of the body is glossy and has a glossiness of 65 to 110 GU as measured by the glossiness 20° method.

4. The blow-molded multi-layer article according to claim 1, wherein the surface roughness is the same over the length and / or width of the outer surface of the body.

5. The blow-molded multi-layer article according to claim 1, wherein the article is a bottle, and wherein the neck is defined by a wall having an inner surface and an outer surface; wherein the neck does not have a color gradient; and wherein a portion of the outer surface of the neck comprises the A layer, and wherein a portion of the outer surface of the neck comprises the B layer.

6. The blow-molded multi-layer article according to claim 1, wherein the article has an opacity of 70% to 95% as measured by the opacity test method, and wherein the change in opacity over the length of the article is less than 25%.

7. The blow-molded multi-layer article according to claim 1, wherein the article has a critical nominal load of greater than 100 N as measured by the critical nominal load method.

8. The blow-molded multi-layer article according to claim 1, wherein the article has a critical nominal load of greater than 105 as measured by the critical nominal load method.

9. The blow-molded multi-layer article according to claim 1, wherein the article has a critical nominal load of greater than 110 as measured by the critical nominal load method.

10. The blow-molded multi-layer article according to claim 1, wherein the effect pigment is a pearlescent pigment, and wherein the effect pigment accounts for 0.01% to 10% by weight of the B layer.

11. The blow-molded multi-layer article according to claim 1, wherein the wall has a thickness of 250 μm to 1 mm as measured by the local wall thickness method, and the average thickness of the wall panel varies by less than 50% along the length of the wall as measured by the local wall thickness method.

12. The blow-molded multi-layer article according to claim 1, wherein the wall has a thickness of 300 μm to 700 μm as measured by the local wall thickness method, and the average thickness of the wall panel varies by less than 30% along the length of the wall as measured by the local wall thickness method.

13. The blow-molded multi-layer article according to claim 1, wherein the wall has a thickness of 400 μm to 600 μm as measured by the local wall thickness method, and the average thickness of the wall panel varies by less than 10% along the length of the wall as measured by the local wall thickness method.

14. The blow-molded multi-layer article according to claim 1, wherein the wall has a thickness of 450 μm to 575 μm as measured by the local wall thickness method, and the average thickness of the wall panel varies by less than 10% along the length of the wall as measured by the local wall thickness method.

15. The blow-molded multi-layer article according to claim 1, wherein the thermoplastic resin is selected from the group consisting of: polyethylene terephthalate (PET), ethylene glycol-modified polyethylene terephthalate (PETG), polystyrene (PS), polycarbonate (PC), polyvinyl chloride (PVC), polyethylene naphthalate (PEN), polycyclohexylene dimethylene terephthalate (PCT), diol-modified PCT copolymer (PCTG), copolyester of cyclohexane dimethanol and terephthalic acid (PCTA), polybutylene terephthalate (PBCT), acrylonitrile-styrene (AS), styrene-butadiene copolymer (SBC), low density polyethylene (LDPE), linear low density polyethylene (LLPDE), high density polyethylene (HDPE), polypropylene (PP), and combinations thereof.

16. The blow-molded multi-layer article according to claim 15, wherein the thermoplastic resin is polyethylene terephthalate (PET).

17. The blow-molded multi-layer article according to claim 1, wherein the article has a non-cylindrical shape.

18. The blow-molded multi-layer article according to claim 1, wherein the outer surface of the wall comprises at least 85% of the A layer.

19. The blow-molded multi-layer article according to claim 1, wherein the outer surface of the wall comprises at least 90% of the A layer.

20. The blow-molded multi-layer article according to claim 1, wherein the outer surface of the wall comprises at least 95% of the A layer.

21. The blow-molded multi-layer article according to claim 1, wherein the effect pigment or the light-shielding pigment is visible through the layer A.

22. A method for manufacturing a blow-molded article according to any one of claims 1-21, comprising the following steps: a. Providing a preform mold for manufacturing a preform; b. Injecting a stream b containing a molten thermoplastic resin and an effect pigment and / or a light-shielding pigment into the preform mold at a flow rate b; c. Simultaneously or within 0.01-2 seconds of injecting the stream b, injecting a stream a containing a molten thermoplastic resin into the preform mold at an initial flow rate a; d. Accelerating the flow rate a to be faster than the flow rate b; e. The stream a blowing through the stream b and flowing towards the outside of the stream b; f. Cooling to form a preform including an outer surface, wherein at least a part of the outer surface contains the solidified stream a, and the solidified stream a generates a color gradient; g. Blow-molding the preform to form the article.

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