Printing ink onto a surface is a common technique for altering the appearance of a surface; however some materials have poor adhesion to inks. In many cases, applying materials in addition to the ink creates a potential source of contamination.
Etching (including mold-etching) and frosting are often used to provide textured surfaces. Textured surfaces can also be applied to some surfaces (e.g., polymeric film) via embossing. A drawback of these techniques is that they require relatively expensive, custom tools for each image, and significantly restrict the ability to rapidly change the image.
There is a need for surface images that can be produced without adding materials and where modification of the tool surface is temporary, and can be can be quickly and inexpensively changed.
In one aspect, the present disclosure describes a first article having a first major surface with at least first and second regions, the first region comprising a plurality of first structures having a first pitch and a first surface roughness (i.e., Ra, Rq, Rz, Rsk, Rku, Sdq, Sdr, Sds, Ssc, Sal, Str, Spk, Sk, or Sm as used herein), the second region comprising a plurality of second structures having a second pitch and a second surface roughness, wherein the first and second pitches are the same (i.e., none of the first and second pitches varies by more than 2% from the average of the first and second pitches (e.g., if 5 randomly selected first pitches were 100.0, 100.3, 100.1, 100.2, and 100.1, and 5 randomly selected first pitches were 100.1, 99.9, 100.2, 100.0, and 100.1, the average of the first and second pitches is 100.1), wherein the first surface roughness is not greater than 50 (in some embodiments, not greater than 40, 30, 25, 20, 15, 10, 5, 4, 3, 2, or even not greater than 1) percent of the second surface roughness, and wherein at least a portion of the at least first and second regions have a surface roughness difference between them that together exhibit at least a portion of a first image. In some embodiments, at least a portion of the at least first and second regions have a surface roughness difference (in some embodiments, the difference is at least 5 or 10 percent) between them that together exhibit at least a portion of a second, third, fourth, fifth, and/or more image. Typically, the first outer surface is free of ink.
In some embodiments, the first article further comprises a third (fourth, fifth, or more) region comprising a plurality of third structures having a third (fourth, fifth, or more) pitch, and a third (fourth, fifth, or more) surface roughness, wherein the first, second, third (fourth, fifth, or more) pitches are the same. Typically, the first surface roughness is not greater than 50 (in some embodiments, not greater than 40, 30, 25, 20, 15, 10, 5, 4, 3, 2, or even not greater than 1) percent of the second and third (fourth, fifth, or more) surface roughness. In some embodiments, at least a portion of the at least two of the first, second, third, fourth, fifth and/or more regions have a surface roughness difference (in some embodiments, the difference is at least 5 or 10 percent) between them that together exhibit at least a portion of a second, third, fourth, fifth, and/or more image.
In another aspect, the present disclosure provides a second article having a first major surface with at least first and second regions, the first region comprising a plurality of first structures and having a first surface roughness (i.e., Ra, Rq, Rz, Rsk, Rku, Sdq, Sdr, Sds, Ssc, Sal, Str, Spk, Sk, or Sm as used herein), the second region comprising a plurality of second structures and having a second surface roughness, wherein the first and second regions join together with no height discontinuity line, wherein the first surface roughness is not greater than 50 (in some embodiments, not greater than 40, 30, 25, 20, 15, 10, 5, 4, 3, 2, or even not greater than 1) percent of the second surface roughness, and wherein at least a portion of the at least first and second regions have a surface roughness difference between them that together exhibit at least a portion of a first image. “Height discontinuity line” refers to a sharp or sudden change in surface height such as the ‘witness lines’ or ‘fault lines’ that occur in a surface that has been printed, mechanically embossed with a tool or etched with a mask. A height discontinuity line extends along the border of two adjacent regions, and the change in surface height across the discontinuity line is more than 1 micrometer. In some embodiments, at least a portion of the at least first and second regions have a surface roughness difference (in some embodiments, the difference is at least 5 or 10 percent) between them that together exhibit a second, third, fourth, fifth, and/or more image. Typically, the first outer surface is free of ink.
In some embodiments, the second article further comprises a third (fourth, fifth, or more) region comprising a plurality of third structures and having a third (fourth, fifth, or more) surface roughness, wherein there is no height discontinuity line where adjacent regions join together. Typically the first surface roughness is not greater than 80 (in some embodiments, not greater than 90, or even not greater than 80) percent of the second and third (fourth, fifth, or more) surface roughness. In some embodiments, at least a portion of the at least two of the first, second, third, fourth, fifth and/or more regions have a surface roughness difference between (in some embodiments, the difference is at least 5 or 10 percent) them that together exhibit at least a portion of a second, third, fourth, fifth, and/or more image. In some embodiments, the first and second (third fourth, fifth, or more) structures have a pitch, wherein the pitch is the same. In some embodiments, the first major surface of the second article has a matte finish appearance.
In another aspect, the present disclosure describes a method of making embodiments of articles described herein, the method comprising:
providing tooling having a patterned face (e.g., the face of the tooling having a desired pattern at least partially filling a portion of the cavities); and
contacting a surface of a polymeric material to provide the article.
In another aspect, the present disclosure describes a method of making embodiments of articles described herein, the method comprising:
In another aspect, the present disclosure describes a method of making embodiments of articles described herein, the method comprising:
In another aspect, the present disclosure describes a method of making embodiments of articles described herein, the method comprising:
providing a rotatable tooling roll having a patterned face;
providing a rotatable nip roll positioned with respect to the tooling roll such that there is an infeed nip between the tooling roll and nip roll;
introducing a continuous stream of UV curable polymeric material and a carrier film into the infeed nip while driving one of the tooling roll or nip roll, wherein the carrier film is closer to the nip roll than the UV curable polymeric material; and
curing the UV curable polymeric material
to provide the article.
In another aspect, the present disclosure describes a method of making embodiments of articles described herein, the method comprising:
In another aspect, the present disclosure describes a method of making embodiments of articles described herein, the method comprising:
providing a rotatable tooling roll having a patterned face;
providing a rotatable nip roll positioned with respect to the tooling roll such that there is an infeed nip between the tooling roll and nip roll; and
introducing a continuous stream of extrudable polymeric material into the infeed nip while driving at least one of the tooling roll or nip roll to provide the article.
In another aspect, the present disclosure describes a method of making embodiments of articles described herein, the method comprising:
providing a rotatable tooling roll having a patterned face comprising cavities;
providing a rotatable nip roll positioned with respect to the tooling roll such that there is an infeed nip between the tooling roll and nip roll;
applying a first material (e.g., a fugitive material (e.g., fugitive liquid)) to a portion of the face of the tooling roll in a desired pattern at least partially filling a portion of cavities; and
introducing a continuous stream of extrudable polymeric material into the infeed nip while driving at least one of the tooling roll or nip roll to provide the article.
Exemplary uses of articles described herein include tool-less macro-patterning of transflectors, customized appearance for retroreflective sheeting, incorporation of security features (both overt and covert), decorative patterns for lighting diffusers, images or logos in medical films without inks or contamination, optical films with regions of higher and lower transmission (or haze or reflectivity), abrasives with regions of higher and lower cutting strength, acoustic films with regions of higher and lower sound absorption, perforated filtration films with regions of smaller and larger holes, identification cards or license plates with a unique digital identification, and consumer products with custom images (e.g., trademark indicia over a matte texture).
Referring to
Referring to
In some embodiments, methods described herein further comprise removing first (and/or second (or more), if present) material (e.g., a fugitive and magnetic material(s)) from the face of the tooling roll prior to the roll completing a full revolution from where the material(s) was applied to a portion of the face of the tooling roll in the desired pattern to at least partially fill a portion of cavities.
A fugitive material (e.g., a fugitive liquid) can be removed from the face of the tooling, for example, by conventional techniques such as convection heating by blowing or impinging hot air via air nozzles, slot jets or perforated plate impingement, conductive heating by heating the tooling roll with steam or hot oil, or infrared heating by using radiant heat provided, for example, by quartz tube lamps or plate coils. Combinations of the heating techniques can be also used such as blowing hot air onto one side of the liquid and using hot oil to conductively heat the roll.
A magnetic material can be removed from the face of the tooling, for example, by changing the surface field or electrostatic charge similar to a Xerographic process.
An exemplary casting apparatus 20 for making an article described herein is shown in
An exemplary casting apparatus 120 for making an article described herein is shown in
Another exemplary casting apparatus 220 for making an article described herein is shown in
Curable polymeric material that forms the array of elements can be cured in one or more steps. For example, radiation sources (e.g., 129, 229) expose a curable polymeric material (e.g., a curable resin) to actinic radiation (e.g., ultraviolet light, visible light, etc.) depending upon the nature of the curable polymeric material in a primary curing step through overlay film (e.g., 121, 221). As can be appreciated by one of skill in the art, the selected overlay film need not be completely or 100 percent transparent to all possible wavelengths of actinic radiation that may be used in curing the curable polymeric material.
Alternatively, curing can be performed by irradiation through a transparent tooling roll (e.g., 25, 125, 225), such as disclosed in U.S. Pat. No. 5,435,816 (Spurgeon et al.). Tool (e.g., 25, 125, 225) has a molding surface having a plurality of cavities opening thereon which have the shape and size suitable for forming desired elements (e.g., cube-corner elements). The cavities, and thus resultant elements may be, for example cube-corner elements such as three sided pyramids having one cube-corner each (e.g., such as are disclosed in the U.S. Pat. No. 4,588,258 (Hoopman)) have a rectangular base with two rectangular sides and two triangular sides such that each element has two cube-corners each (e.g., such as are disclosed in U.S. Pat. No. 4,938,563 (Nelson et al.)), or of other desired shape, having at least one cube corner each (e.g., such as are disclosed in U.S. Pat. No. 4,895,428 (Nelson et al.)). It will be understood by those skilled in the art that any cube-corner element may be used in accordance with the present disclosure. The shape of the tooling cavities, and thus resultant article structures, may also be, for example, curve-sided prisms, truncated pyramids, lenslets, micro-needles, fasteners, stems, micro-flow channels and a variety of other geometries. The pitch of the surface refers to the repeat distance from one cavity or structure to the next adjacent cavity or structure.
The tooling can be used in a number of different forms, depending on the needs of the process being utilized. Flat plates or inserts are typically used for stamping, compression molding or injection molding processes. Rollers or cylinders are typically used for continuous processes such as coating, embossing and film extrusion. Some continuous processes utilize tooling in the form of a belt in order to integrate additional process steps or to enable the use of thin tooling plates that have been joined together.
Tooling roll (e.g., 25, 125, 225) should be such that the cavities will not deform undesirably during fabrication of the composite article, and such that the array of elements can be separated therefrom after solidification or curing.
Materials useful in forming the tooling roll (e.g., 25, 125. 225) preferably machine cleanly without burr formation, exhibit low ductility and low graininess, and maintain dimensional accuracy after groove formation. The tool can be made from polymeric, metallic, composite, or ceramic materials. In some embodiments, curing of the curable polymeric material will be performed by applying radiation through the tool. In such instances, the tool should be sufficiently transparent to permit irradiation of the polymeric material therethrough. Illustrative examples of materials from which tools for such embodiments can be made to include polyolefins and polycarbonates. Metal tools are typically preferred, however, as they can be formed in desired shapes. The primary curing can completely or partially cure the elements.
Second radiation source (e.g., 230) can be provided to cure the polymeric material after article (e.g., 231) has been removed from tool (e.g., 225). The extent of the second curing step is dependent on a number of variables, among them the rate of feed through of the materials, composition of the polymeric material, nature of the crosslinking initiators used in the curable polymeric material, and the geometry of the tool. Illustrative examples include electron beam exposure and actinic radiation (e.g., ultraviolet radiation, visible light radiation, and infrared radiation).
Removal of the article (e.g., 231) from the tooling (e.g., 231) typically generates sufficient mechanical stresses to fracture the minimal land area between the elements, if any, that exists between the individual elements of the article. The decoupled, independent nature of the discrete elements and strong bond of each independent element to the overlay film may give the article substantial flexibility, while, for example, for cube-corner elements retainment of high levels of retroreflective performance after undergoing mechanical deformation stresses. Heat treatment of article (e.g., 231) may optionally be performed after it is removed from the tool. Heating serves to relax stresses that might have developed in the overlay film or elements, and to drive off unreacted moieties and reaction by-products. Typically, such treatment involves heating the article to an elevated temperature (e.g., above the glass transition temperature of the subject curable polymeric material).
The overlay film can be any conventional films used for such purpose, including ionomeric ethylene copolymers, plasticized vinyl halide polymers, acid-functional ethylene copolymers, aliphatic polyurethanes, aromatic polyurethanes, other light transmissive elastomers, and combinations thereof.
The carrier film can be any conventional films, papers or foils used for such purpose, including polyester films, cellulose acetate films, polypropylene films, polycarbonate films, printing paper, kraft paper, security paper, packaging paper, aluminum foil, and copper foil.
Exemplary polymeric materials include polycarbonates; polypropylenes; polyethylenes; styrene acrylonitrile copolymers; styrene (meth)acrylate copolymers; polymethylmethacrylate; styrene maleic anhydride copolymers; nucleated semi-crystalline polyesters; copolymers of polyethylenenaphthalate; polyimides; polyimide copolymers; polyetherimide; polystyrenes; syndiodactic polystyrene; polyphenylene oxides; copolymers of acrylonitrile, butadiene, and styrene; functionally-modified polyolefins; and polyurethanes.
Exemplary UV curable polymeric materials include reactive resin systems capable of being cross-linked by a free radical polymerization mechanism by exposure to actinic radiation (e.g., electron beam, ultraviolet light, or visible light). These materials may also be polymerized thermally with the addition of a thermal initiator (e.g., benzoyl peroxide). Radiation-initiated cationically polymerizable resins also may be used. Reactive resins suitable for forming the array of elements may be blends of photoinitiator and at least one compound bearing an acrylate group. Preferably the resin blend contains a monofunctional, a difunctional, or a polyfunctional compound to ensure formation of a cross-linked polymeric network upon irradiation.
Illustrative examples of resins that are capable of being polymerized by a free radical mechanism that can be used herein include acrylic-based resins derived from epoxies, polyesters, polyethers, and urethanes, ethylenically unsaturated compounds, aminoplast derivatives having at least one pendant acrylate group, isocyanate derivatives having at least one pendant acrylate group, epoxy resins other than acrylated epoxies, and mixtures and combinations thereof. The term acrylate is used here to encompass both acrylates and methacrylates.
Materials for at least partially filling cavities (permanently or temporarily (i.e., those such as fugitive materials that can be removed) include epoxies, urethanes, acrylates, and waxes. In some embodiments, the materials are fugitive solids (e.g., sacrificial binders (e.g., polypropylene carbonate or polyethylene carbonate) and water soluble materials (e.g., polyvinyl alcohol and polyethylene oxide) and fugitive fluids (e.g., diols (e.g., propylene glycol, diethylene glycol, triethylene glycol, and ethylene glycol), water and aqueous solutions, mineral oils (petrochemicals), organic oils (lipids), organic solvents (e.g., ethanol), and mixtures thereof. In some embodiments, the fugitive liquid comprises liquid selected from the group consisting of propylene glycol, propylene glycol and ethanol, diethylene glycol, diethylene glycol and ethanol, triethylene glycol, triethylene glycol and ethanol, ethylene glycol, ethylene glycol and ethanol, water, and water and ethanol). In some embodiments, the material is a magnetic material such as powders made of iron, nickel, ferrite, magnetite, samarium cobalt, and neodymium iron boron.
Techniques for at least partially filling cavities as material include those generally known in the art. Exemplary ways for applying the fugitive liquid to a portion of the face of the tooling roll in a desired pattern at least partially filling a portion of cavities include via contact printing, non-contact printing, pattern coating, and combinations thereof. Examples of contact printing include printing surface makes direct contact with a tool: direct and offset flexographic, direct and offset gravure, direct and offset lithographic, direct and offset screen printing. Examples of non-contact printing include ink-jet, spray, acoustic, electrostatic, and digital deposition. Examples of pattern coating include patterned die (for large rectangles) and needle (for downstream lines). An example of a combination of printing techniques is ink-jetting on a transfer roll instead of on a tool. Any of a variety of printing techniques, for example, may be sued to deposit permanent and semi-permanent or temporary materials.
In some embodiments, a second (or more) material may be further applied to a portion of the face of the tooling in a desired pattern at least partially filling a portion of the cavities.
Typically, the Ra and Rz surface roughnesses are not greater than 200 micrometers (in some embodiments, not greater than 175, 150, 100, 75, 70, 60, 50, 40, 30, 25 or even not greater than 20 micrometers; in some embodiments, in a range from 20 micrometers to 175 micrometers, 20 micrometers to 150 micrometers, 20 micrometers to 100 micrometers, 20 micrometers to 75 micrometers, or even from 20 micrometers to 50 micrometers).
Typically, the Rq surface roughnesses are not greater than 100 micrometers (in some embodiments, not greater than 90, 80, 75, 70, 60, 50, 40, 30, 25 20, or even not greater than 10 micrometers; in some embodiments, in a range from 10 micrometers to 100 micrometers, 10 micrometers to 75 micrometers, 10 micrometers to 50 micrometers, or even from 10 micrometers to 25 micrometers).
Ra is the arithmetic average of the absolute values of the surface height measured relative to the mean plane and recorded within the evaluation area,
wherein Z is the surface height measured relative to the mean plane, and N and M are the number of data points in the x- and y-directions.
Rq is the root mean square average of the surface height measured relative to the mean plane and recorded within the evaluation area,
wherein Z is the surface height deviation measured relative to the mean plane, and N and M are the number of data points in the x- and y-directions.
Rz is the average maximum surface height of the ten largest peak-to-valley separations in the evaluation area,
wherein H is a peak height and L is a valley height, and H and L are referenced to the mean plane. Rz encompasses the range of surface heights present in a field of view. Note that the “VISION FOR PROFILERS” (version 4.20) software by Veeco Instruments, Santa Barbara, Calif. used for the examples excludes an 11×11 region around each H or L point to avoid all peak or valley points emanating from one spike or hole.
Rsk, or skewness is a measure of the symmetry of the profile about the mean line. Rsk provides information about asymmetrical profiles for surfaces with the same values for Ra, Rq, etc. Negative skew values indicate a predominance of valleys, while positive skew values are observed for surfaces with a predominance of peaks.
wherein Z is the surface height deviation measured relative to the mean plane, Rq is as defined above, N and M are the number of data points in the x- and y-directions.
Rku, or kurtosis is a measure of the spread of height values in a data set; it is a measure of the peakedness of a surface about the mean plane. It is also a measure of randomness of observed heights.
wherein Z is the surface height deviation measured relative to the mean plane, Rq is as defined above, N and M are the number of data points in the x- and y-directions.
Sdq is the Root Mean Square (RMS) Surface Slope, also known as the RMS Gradient, comprising the surface. Sdq is a general measurement of the slopes that comprise the surface. As such, it can be used to differentiate surface features with similar average roughness Ra (Sa), as defined above. When evaluated over the measured area, a, the Sdq is be represented as follows:
wherein Z is the surface height deviation measured relative to the mean plane.
Sdr is the developed interfacial area ratio. It is the ratio of the increment of the interfacial area of a surface over the sampling area. A perfectly flat surface would have an Sdr of 0%. Sdr generally increases with spatial intricacy of the surface texture independent of Ra (Sa). It is be defined as
Sds, the Summit Density, is the number of summits per unit area that make up the surface. Summits are derived from peaks. A peak is defined as any point that is above all eight nearest neighbors. Peaks are constrained to be separated by at least 1% of the minimum X and Y dimension comprising the 3-D measurement area. Furthermore, summits are found only above a threshold that is 5% of Rz above the mean plane.
Ssc is the Mean Summit Curvature comprising the summits found for the SDS calculations. Ssc can help predict the degree of elastic and plastic deformation of a surface under different loading conditions. When evaluated only over the summit features, the Ssc can be represented as follows:
Sal, is the fastest decay autocorrelation length. It is a measure of the distance over the surface in an optimum direction such that the new location has minimal correlation with the original location. Sal is a quantitative measure of the distance along the surface by which one would find a texture that is statistically different from the original location.
S
al=Length of fastest decay ACF in any direction
wherein ACF is autocorrelation function.
wherein ACF is autocorrelation function. For a surface with a dominant lay, the Str tends towards zero. For a surface with no lay, or spatially isotropic, St, is equal to 1.00.
Spk is the surface peak height and is an estimate of the peaks above the main flat part of the surface that will be worn away during the running-in period.
Sk is the core roughness depth, which is the depth of the working part of the surface. In other words, the main flat part of the bearing area curve.
Sm, the Surface Material Volume, is the amount of material contained in the surface peaks from 0% to 10% of the bearing area ratio.
The Y Crossings is a measure of the number of times that the data cross zero when scanned in the Y directions. This is reported as a number of crossings per unit length.
Surface roughnesses can be obtained utilizing the descriptions above using a confocal microscope (available under the trade designation “KEYENCE VK9710” from Keyence Corporation, Elmwood Park, N.J.) to collect data over a test area that is then analyzed software marketed under the trade designation “VISION FOR PROFILERS” (version 4.20) by Veeco Instruments, Santa Barbara, Calif., which utilizes the surface roughnesses descriptions described above. The test area size and orientation should be the same in both the first and second regions, and the test area size should be approximately 200×200 micrometers. Somewhat larger or smaller test area dimensions may be chosen in order to ensure the test area fits completely within each region without overlapping and to create test areas with four or more microstructures. Seven surface roughness measurements were averaged to determine the surface roughness of a surface.
Any of a variety of configurations of the first and second regions (and optional additional regions) can be provided. For example, in some embodiments a region may be in any of a variety of geometric shapes such as a circle, oval, square, rectangle, triangle, alphanumeric, etc. In another aspect, for example, in some embodiments, there is a plurality of first regions within a matrix of the second region. In some embodiments, there is a plurality of second regions within a matrix of the first region. In some embodiments at least a portion of the first and second regions (and optionally other regions if present) collectively exhibit at least a first (second, third, or more) image or indicia (which may be, for example, a trademark or copyrighted material, including a registered trademark or registered copyright as defined under any of the countries, territories, etc. of the world (including the United States)). The configurations of the first and second regions (optional additional regions) are typically created by the arrangement of the tool used to create elements in the article and/or the pattern of fugitive fluid used in the process for making the article.
In some embodiments, an image may be, for example, a positive image or a negative image. An exemplary positive image is illustrated in
In some embodiments, the first region is translucent and/or the second region is transparent. In some embodiments, both the first and second regions are translucent.
Further, optionally other regions, if present can independently be translucent or transparent. The translucency of a region can be affected, for example, by the presence of colorants, pigments, fillers, etc. in the polymeric material and/or the effect from use of the fugitive fluid in the process of making the article.
Typically, the first outer surface of the article is free of ink. In standard printing applications an ink can be a “colorizing agent”, a “translucentizing agent” or an “opacifying agent” which is added to a substrate. The term “colorizing agent” refers to a chemical agent having the property of changing the color of the substrate in areas coated or impregnated with the agent. The term “translucentizing agent” refers to a chemical agent having the property of increasing the translucence of areas of a substrate coated or impregnated with that agent. Similarly, the term “opacifying agent” refers to a chemical agent having the property of increasing the opacity (i.e., decreasing the translucence) of a substrate coated or impregnated with that agent.
In some embodiments, articles described herein the first and second regions each have a haze value, wherein the first and second haze values have a difference between them of at least 1%. In some embodiments, articles described herein the first and second regions each have a visible transmission value, and wherein the first and second visible transmission values have a difference between them of at least 1%. In some embodiments, articles described herein the first and second region each have a clarity value, and wherein the first and second clarity values have a difference between them of at least 1%.
In some embodiments, the first major surface of the article has a hard coat thereon. Commercially available materials for providing a hardcoat include liquid-resin based materials such as those available from California Hardcoating Co., San Diego, Calif., under the trade designation “PERMANEW”; and from Momentive Performance Materials, Albany, N.Y. under the trade designation “UVHC”. Hardcoat materials can be applied to the surface, for example, with conventional liquid coating techniques and cured with either heat or UV treatment.
In some embodiments, the article comprises at least one of colorant or pigment. In some embodiments, the article comprises opaque filler. Exemplary colorants and pigments include titanium dioxide, phthalo blue, red iron oxide, various clays, calcium carbonate, mica, silicas, and talcs. Exemplary fillers include glass beads or fibers, carbon black, flock and mineral reinforcements. Colorants, pigments, and/or fillers can be incorporated into the articles described herein, for example, by adding them using conventional techniques into the polymeric material.
In some embodiments, the cavities of the patterned face of the tooling roll have a pitch in a range from 0.1 micrometer to 1000 micrometers. In some embodiments, the cavities have openings in a range from 0.05 micrometer to 1000 micrometers. In some embodiments, the cavities have depth in a range from 0.02 micrometer to 500 micrometers.
In some embodiments, the first and second pitches (and optionally other pitches, if present) in regard to the article, and since they typically result from to tool (e.g., 25, 125), the pitch of the cavities in the tool, are in a range from 0.1 micrometer to 1000 micrometers.
Exemplary uses of articles described herein include tool-less macro-patterning of transflectors, customized appearance for retroreflective sheeting, incorporation of security features (both overt and covert), decorative patterns for lighting diffusers, images or logos in medical films without inks or contamination, optical films with regions of higher and lower transmission (or haze or reflectivity), abrasives with regions of higher and lower cutting strength, acoustic films with regions of higher and lower sound absorption, perforated filtration films with regions of smaller and larger holes, identification cards or license plates with a unique digital identification, and consumer products with custom images (e.g., trademark indicia over a matte texture).
1A. An article having a first major surface with at least first and second regions, the first region comprising a plurality of first structures having a first pitch and a first surface roughness, the second region comprising a plurality of second structures having a second pitch and a second surface roughness, wherein the first and second pitches are the same, wherein the first surface roughness measure is not greater than 50 percent of the second surface roughness measure, and wherein at least a portion of the at least first and second regions have a surface roughness difference between them that together exhibit at least a portion of a first image.
2A. The article of embodiment 1A, wherein the first surface roughness measure is not greater than 30 percent of the second surface roughness measure
3A. The article of either embodiment 1A or 2A, wherein the surface roughness difference between the first and second surface roughnesses is at least 5 percent.
4A. The article of any preceding embodiment, wherein the first and second surface roughnesses are at least one of Ra, Rq, Rz, or Sds.
5A. The article of any preceding embodiment, wherein first image includes at least one of alphanumerics a first trademark indicia or a first copyrighted indicia.
6A. The article of any preceding embodiment, wherein the second region is transparent.
7A. The article of any preceding embodiment, wherein the first region is translucent.
8A. The article of any preceding embodiment, wherein the second region is translucent.
9A. The article of any preceding embodiment, wherein the first and second regions each have a haze value, and wherein the first and second haze values have a difference between them of at least 1%.
10A. The article of any preceding embodiment, wherein the first and second regions each have a visible transmission value, and wherein the first and second visible transmission values have a difference between them of at least 1%.
11A. The article of any preceding embodiment, wherein the first and second regions each have a clarity value, and wherein the first and second clarity values have a difference between them of at least 1%.
12A. The article of any preceding embodiment, wherein the first outer surface is free of ink.
13A. The article of any preceding embodiment, wherein the first and second pitches are in a range from 0.1 micrometer to 1000 micrometers.
14A. The article of any preceding embodiment, wherein there is a plurality of first regions within a matrix of the second region.
15A. The article of any of embodiments 1A to 13A, wherein there is a plurality of second regions within a matrix of the first region.
16A. The article of any preceding embodiment, wherein the first surface roughness is not greater than 200 micrometers.
17A. The article of any preceding embodiment, wherein the first region comprises an electrically function area.
18A. The article of any preceding embodiment, wherein the first region comprises metal.
19A. The article of any preceding embodiment, wherein the first region comprises semi-metallic.
20A. The article of any preceding embodiment, wherein the first and second regions have different dielectric properties.
21A. The article of any preceding embodiment, wherein the first major surface of the article has a hard coat thereon.
22A. The article of any preceding embodiment comprising at least one of colorant or pigment.
23A. The article of any preceding embodiment comprising opaque filler.
1B. A method of making the article of any of embodiments 1A to 23A, the method comprising:
introducing a continuous stream of UV curable polymeric material and a carrier film into the infeed nip while driving one of the tooling roll or nip roll, wherein the carrier film is closer to the nip roll than the UV curable polymeric material; and
providing tooling having a patterned face (e.g., the face of the tooling having a desired pattern at least partially filling a portion of the cavities); and
contacting a surface of a polymeric material to provide the article.
1F. A method of making the article of any of embodiments 1A to 23A, the method comprising:
providing tooling having a patterned face (e.g., the face of the tooling having a desired pattern at least partially filling a portion of the cavities); and
contacting a surface of a polymeric material to provide the article.
1M. A method of making the article of any of embodiments 1H to 24H, the method comprising:
Advantages and embodiments of this invention are further illustrated by the following examples, but the particular materials and amounts thereof recited in these examples, as well as other conditions and details, should not be construed to unduly limit this invention. All parts and percentages are by weight unless otherwise indicated.
Example 1 was prepared by extrusion casting a 0.14 millimeter (0.0055 inch) thick poly(methyl methacrylate) (obtained under trade designation “PLEXIGLASS VO44” from Arkema Inc., Philadelphia, Pa.) film at 9.1 meters per minute (30 feet per minute). The temperature of the poly(methyl methacrylate) to be extruded was about 243° C. (470° F.). The extruded film was nipped into the surface of a 254 millimeter (10 inch) diameter diamond turned roll having both a down web thread cut and a cross web thread cut creating a 140 micrometer pitch intersecting pattern. The water temperature flowing inside the roller was set to 82° C. (180° F.).
A mixture of propylene glycol (CAS Registry Number: 57-55-6; obtained from Alfa Aesar, Ward Hill, Mass.) and ethanol (CAS Registry Number: 64-17-5; obtained from Branntag Great Lakes, Wauwatosa, Wis.) was prepared at a 1:1 ratio by weight. A film of the fluid mixture was spread onto a glass plate with a Mayer rod (Number RDS 22). A flexographic plate (obtained under trade designation “KODAK NX 0.045 PLATE” from Southern Graphics, Brooklyn Park, Minn.) was taped onto a handheld paint roller and rolled over the glass plate to transfer a thin layer of fluid to the flexographic pattern.
The paint roller with flexographic plate and layer of fluid was then pressed for one revolution against the diamond turned roll during the film extrusion casting, transferring a pattern of the fluid to the film. The film was collected and a single, clear image of the flexographic pattern was observed.
A confocal microscope (under the trade designation “KEYENCE VK9710” from Keyence
Corporation, Elmwood Park, N.J.) was used to measure roughness parameters in a 200 micrometer by 200 micrometer area in both regions of the film. The data was analyzed using software marketed under the trade designation “VISION FOR PROFILERS” (version 4.20) by Veeco Instruments, Santa Barbara, Calif., producing the following results (based on seven measurements per sample):
Example 2 was prepared as described in Example 1, except the temperature of the diamond turned roll was set to 71° C. (160° F.).
A clear image was observed followed by a second less clear image.
Example 3 was prepared as described in Example 1, except the temperature of the diamond turned roll was set to 60° C. (140° F.).
A clear image was observed followed by two other less clear images.
Example 4 was prepared as described in Example 1, except the temperature of the diamond turned roll was set to 49° C. (120° F.).
A clear image was observed followed by three other less clear images.
Example 5 was prepared as described in Example 1, except a 0.27 millimeter (0.0106 inch) thick polycarbonate (obtained under trade designation “MAKROLON OD2015” from Bayer Corp., Pittsburgh, Pa.) was extrusion cast onto the tooling roll. The fugitive liquid was deionized water and was applied to the diamond turned roll surface with a small brush as a stripe approximately 1 millimeter wide and 30 centimeters long.
A clear image was observed followed by no secondary images.
Example 6 was prepared as described in Example 5, except propylene glycol (CAS Registry Number: 57-55-6; obtained from Alfa Aesar), was used as the fugitive liquid.
A clear image was observed followed by one other less clear image.
Example 7 was prepared as described in Example 5, except ethylene glycol (CAS Registry Number: 107-21-1; obtained from Mallinckrodt Baker, Phillipsburg, N.J.), was used as the fugitive liquid.
A clear image was observed followed by five other less clear images.
Example 8 was prepared as described in Example 5, except diethylene glycol (CAS Registry Number: 111-46-6; obtained from Alfa Aesar), was used as the fugitive liquid.
A clear image was observed followed by four other less clear images.
Example 9 was prepared as described for Example 5, except triethylene glycol (CAS Registry Number: 112-27-6; obtained from Alfa Aesar), was used as the fugitive liquid.
A clear image was observed followed by six other less clear images.
Example 10 was prepared by extrusion casting a 0.24 millimeter (0.0095 inch) thick polyethylene terephthalate copolymer, PETG, (obtained under trade designation “EASTAR 6763” from Eastman Chemical Company, Kingsport, Tenn.) film at 6.1 meters per minute (20 feet per minute). The temperature of the PETG to be extruded was about 260° C. (500° F.). The extruded film was nipped into the surface of a 305 millimeter (12 inch) diameter diamond turned roll having both a dwn web thread cut and a cross web thread cut creating a 140 micrometer pitch intersecting pattern. The water temperature flowing inside the roller was set to 54° C. (130° F.).
An inkjet printing apparatus (obtained under trade designation “SPECTRA SE128” from FUJIFILM Dimatix, Inc., Santa Clara, Calif.) was used to transfer a pattern of propylene glycol (CAS Registry Number: 57-55-6; obtained from Alfa Aesar) onto the diamond turned roll during the extrusion process. A series of text characters measuring 5 millimeters by 40 millimeters were transferred by the apparatus, with the inkjet head temperature at 49 C. The film was collected and clear images of the text characters were observed as well as repeated images.
A confocal microscope (“KEYENCE VK9710”) was used to measure roughness parameters in a 212 micrometer by 283 micrometer area in both regions of the film. The data was analyzed using software marketed under the trade designation “VISION FOR PROFILERS” (version 4.20), producing the following results (based on seven measurements per sample):
Example 11 was prepared by extrusion casting a 0.32 millimeter (0.0125 inch) thick polypropylene, (obtained under trade designation “TOTAL POLYPROPYLENE 5724” from Total Petrochemicals USA Inc., Houston, Tex.) film at 6.8 meters per minute (22.5 feet per minute). The temperature of the polypropylene to be extruded was about 218° C. (425° F.). The extruded film was nipped into the surface of a 305 millimeter (12 inch) diameter roll having bead-blasted matte texture. The water temperature flowing inside the roller was set to 52° C. (125° F.).
A flexographic proofing instrument (obtained under trade designation “ESIPROOF” from R K Print Coat Instruments of Litlington, United Kingdom) was used to transfer a pattern of propylene glycol (CAS Registry Number: 57-55-6; obtained from Alfa Aesar) onto the matte texture roll during the coating and curing process. The proofing instrument used an anilox roll with 80 cells per linear centimeter (200 cells per linear inch) and a rubber pattern roll with a series of 20 millimeter wide ‘3M’ logos engraved onto the surface by Caliber Engraving, Brea, Calif. A hot air gun (obtained under trade designation HG 2310 LCD from Steinel America Inc., Bloomington, Minn.) was set to 316° C. (600° F.) and used to blow hot air onto the surface of the matte texture roll between the film strip-off and pattern transfer locations. The film was collected and clear images of the logo were observed with no repeated images.
A confocal microscope (“KEYENCE VK9710”) was used to measure roughness parameters in a 770 micrometer by 185 micrometer area in both regions of the film. The data was analyzed using software marketed under the trade designation “VISION FOR PROFILERS” (version 4.20), producing the following results (based on seven measurements per sample):
Example 12 was prepared as described for Example 11, except the proofing instrument used a rubber roll with no engraved pattern resulting in a continuous stripe image on the film. A hazemeter (obtained under trade designation “HAZE-GARD PLUS” from BYK Gardner USA, Silver Springs, Md.) was used to measure the following optical characteristics of the film (data represents the mean and standard deviation of 16 measurements):
Foreseeable modifications and alterations of this disclosure will be apparent to those skilled in the art without departing from the scope and spirit of this invention. This invention should not be restricted to the embodiments that are set forth in this application for illustrative purposes.
This application claims the benefit of U.S. Provisional Patent Application No. 61/539,671, filed Sep. 27, 2011, and U.S. Provisional Patent Application No. 61/422,804, filed Dec. 14, 2010, the disclosure of which is incorporated by reference herein in its entirety.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US11/62899 | 12/1/2011 | WO | 00 | 5/22/2013 |
Number | Date | Country | |
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61539671 | Sep 2011 | US | |
61422804 | Dec 2010 | US |