Patent Application
20190187345
This disclosure relates to reflective material, and more particularly reticulated reflective material for use on protective garments.
Reflective materials have been developed for use in a variety of applications, including road signs, license plates, footwear, and clothing patches to name a few. Reflective materials are often used as high visibility trim materials in clothing to increase the visibility of the wearer. For example, reflective materials are often added to protective garments worn by firefighters, rescue personnel, EMS technicians, and the like.
Retroreflectivity can be provided in a variety of ways, including by use of a layer of tiny glass beads or microspheres that cooperate with a reflective agent, such as a coated layer of aluminum. The beads can be partially embedded in a binder layer that holds the beads to fabric such that the beads are partially exposed to the atmosphere. Incident light entering the exposed portion of a bead is focused by the bead onto the reflective agent, which is typically disposed at the back of the bead embedded in the binder layer. The reflective agent reflects the incident light back through the bead, causing the light to exit through the exposed portion of the bead in a direction opposite the incident direction.
Reflective materials can be particularly useful to increase the visibility of fire and rescue personnel during nighttime and twilight hours. In some situations, however, firefighter garments can be exposed to extreme temperatures during a fire, causing the reflective material to trap heat inside the garment. Under certain conditions, the trapped heat can result in discomfort or even burns to the skin of the firefighter.
In particular, moisture collected under the reflective material may expand rapidly when exposed to the extreme temperature from the fire. if the expanded moisture is unable to quickly permeate through the reflective material, the firefighter can be exposed to extreme temperatures. In some cases, this can result in steam burns on the skin of the firefighter underneath the portions of the garment having the reflective material. Conventional reflective materials, including perforated reflective materials generally exhibit this phenomenon. For example, conventional perforated reflective materials include standard reflective trim having needle punched holes, laser punched holes, slits, or relatively large holes made with a paper punch.
There is a need for reflective articles that are expandable in one or more direction to provide varying levels of brightness and varying degrees of breathability or air/moisture permeability. in general, this disclosure describes reticulated reflective material for use on protective garments that satisfy the aforementioned needs.
In one aspect, there is provided a reticulated reflective article, comprising: a plurality of strands of a reflective material attached to one another at bridging regions in the reflective material and separable from one another between the bridging regions to provide openings in the reflective material, wherein the openings are expandable to provide a variably expandable area, and wherein the reflective materials comprises a reflective major surface and a non-reflective major surface, wherein each of the openings has a longitudinal dimension, a width dimension, and each of the plurality of strands has a thickness, and wherein the reticulated reflective article is expandable in at least one of a longitudinal direction and a width direction.
In sonic embodiments, the article provides a first reflective brightness when separated into a first width dimension between the plurality of strands of reflective material and a second reflective brightness when separated into a second width dimension between the plurality of strands of reflective material. In some embodiments, the reduction in brightness between the first reflective brightness and the second reflective brightness is from at least about 10% reduction in brightness to about a 90% reduction in brightness, wherein both brightnesses are determined according to ASTM E810-03 (2013) when performed on unwashed reticulated reflective articles.
In some embodiments, the change in open area from the first width dimension to the second width dimension is at least 20%, the reduction in brightness between the first reflective brightness and the second reflective brightness is from at least 25% reduction in brightness to about a 90% reduction in brightness, wherein both brightnesses are determined according to ASTM E810-03 (2013) when performed on unwashed reticulated reflective articles, and further wherein the reticulated reflective article has a permeability of at least 5.5 cm/s. In some embodiments, the article provides a first reflective brightness when separated into a first width dimension between the plurality of strands of reflective material having an adhesive layer disposed thereon and a second reflective brightness when separated into a second width dimension between the plurality of strands of reflective material having an adhesive layer disposed thereon. In some embodiments, the first width dimension is less than the second width dimension. In some embodiments, the first reflective brightness is higher than the second reflective brightness.
In some embodiments, non-reflective regions comprise at least 25% of the total surface area of the reflective material. In some embodiments, non-reflective regions comprise at least 50% of the total surface area of the reflective material.
In some embodiments, the reticulated reflective articles further comprise a carrier tape adhered to the reflective major surface of the reflective material. In some embodiments, the reticulated reflective articles further comprise an adhesive layer disposed on one of the major surfaces of the reflective material, wherein the adhesive layer is separable into a plurality of strands disposed on the plurality of strands of the reflective material. In some embodiments, the reticulated reflective articles further comprise a substrate disposed on a major surface of the adhesive layer opposite the reticulated reflective article. In some embodiments, the substrate is elastorneric.
In some embodiments, the article has a first brightness when it is in a non-expanded form and a second brightness when it is in an expanded form. In some embodiments, the article has a first permeability when it is in a non-expanded form and a second permeability when it is in an expanded form. In some embodiments, the reflective material is selected from at least one of optical films, microprismatic film and microsphere films.
In another aspect, the present disclosure provides a reticulated reflective article, having a longitudinal direction and a width direction, and comprises: a plurality of regions of a reflective material separable from one another to provide openings in the reflective material, wherein the reflective materials comprises a reflective major surface and a non-reflective major surface, wherein each of the openings has a longitudinal dimension, and a width dimension, and wherein the reticulated reflective article is expandable in at least two directions. In some embodiments, the articles further comprise a multitude of the plurality of regions extending radially from a common intersection.
In another aspect, the present disclosure provides a reflective article having at least a longitudinal dimension and a width dimension and comprises: a reflective layer comprising optical film, microprismatic film, microsphere film, or combinations thereof having a plurality of slits formed therein, the plurality of slits having a slit direction and each slit having a top and an opposing bottom direction along the slit direction, the slit direction being at least substantially parallel to the longitudinal dimension or the width dimension, the plurality of slits comprising at least two adjacent slits offset with respect to an axis perpendicular to the slit direction, wherein the top of and bottom of at least two adjacent slits are not greater than 5 mm apart along the slit direction when the reflective article is in a pre-stretched condition.
In some embodiments, the article provides a first reflective brightness when separated into a first width dimension between the plurality of regions of reflective material and a second reflective brightness when separated into a second width dimension between the plurality of regions of reflective material. in some embodiments, the reduction in brightness between the first reflective brightness and the second reflective brightness is from about 10% reduction in brightness to about a 90% reduction in brightness, wherein both brightnesses are determined according to ASTM E810-03 (2013) when performed on unwashed reticulated reflective articles. In some embodiments, the change in open area from the first width dimension to the second width dimension is at least 20%, the reduction in brightness between the first reflective brightness and the second reflective brightness is from at least 25% reduction in brightness to about a 90% reduction in brightness, wherein both brightnesses are determined according to ASTM E810-03 (2013) when performed on unwashed reticulated reflective articles, and further wherein the reticulated reflective article has a permeability of at least 5.5 cm/s. In some embodiments, the article provides a first reflective brightness when separated into a first width dimension between the plurality of regions of reflective material having an adhesive layer disposed thereon and a second reflective brightness when separated into a second width dimension between the plurality of regions of reflective material having an adhesive layer disposed thereon. In some embodiments, the first reflective brightness is higher than the second reflective brightness.
In some embodiments, the reticulated reflective articles further comprise a carrier tape adhered to the reflective major surface of the reflective material. In some embodiments, the reticulated reflective articles further comprise an adhesive layer disposed on one of the major surfaces of the reflective material, wherein the adhesive layer is separable into a plurality of regions disposed on the plurality of regions of the reflective material. In some embodiments, the reticulated reflective articles further comprise a substrate disposed on a major surface of the adhesive layer opposite the reticulated reflective article. In some embodiments, the substrate is elastomeric.
In some embodiments, the article has a first brightness when it is in a non-expanded form and a second brightness when it is in an expanded form. In some embodiments, the article has a first permeability when it is in a non-expanded form and a second permeability when it is in an expanded form. In some embodiments, the reflective material is selected from at least one of optical films, microprismatic film and microsphere films.
Additional details of these and other embodiments are set forth in the accompanying drawings and the description below. Other features, objects and advantages will become apparent from the description and drawings, and from the claims.
In general, this disclosure describes reticulated reflective material for use on protective garments. The material may include a non-continuous reflective pattern that provides a high-level of reflective brightness, yet provides adequate permeability to prevent exposure to heated moisture and extreme temperatures. in some cases, this disclosure describes the garment itself, i.e., an outer layer or outer shell of a protective outfit. In other cases, this disclosure describes an article, such as a clothing patch that could be added to a protective garment. Ib still other cases, this disclosure describes a protective outfit that includes the non-continuous reflective pattern on an outer shell and additional layers such as a thermal liner and a moisture barrier.
The terms “articles” and “reticulated reflective articles” are used interchangeably herein.
The term “elastomeric” as used herein means comprised of any material that is able to resume its original shape when deforming forces are removed.
The term “reflectivity” as used herein means redirection of light from a given material. The term “retroreflection” as used herein means reflection of light back toward the light source from a given material. The terms “reflectivity” and “retroreflectivity” are used interchangeably herein.
The term “reticulated” as used herein means a net like formation of strands or regions that are joined at certain points.
In some embodiments, the present disclosure provides a reticulated reflective article having a longitudinal direction and a width direction, and including a plurality of strands of a reflective material attached to one another at bridging regions in the reflective material and separable from one another between the bridging regions to provide openings in the reflective material, where the openings provide a variably expandable area, and where the reflective material comprises a reflective major surface and a non-reflective major surface, also where each of the openings has a longitudinal dimension, a width dimension, and each of the plurality of strands has a thickness, and also where the reticulated reflective article is expandable in at least one direction.
In the present disclosure, expansion of the reticulated reflective article is considered as a change in the area of the openings in the reticulated reflective article. Presently disclosed reticulated reflective articles can provide varying amounts of open area when expanded in one or more directions. As the reticulated reflective articles are expanded the amount of open area is increased, resulting in lower brightnesses and increased permeabilites. In some embodiments, expansion can be conducted before the reticulated reflective article is mounted on a substrate. In some embodiments, expansion occurs due to motion of a user, such as for example, when the reticulated reflective article is mounted on an elbow or knee region of active wear.
Referring to
In some embodiments, the openings 22 are larger in the longitudinal direction 12 than in the width dimension. For example, in some embodiments, such as those depicted in
Referring now to
Referring now to
In some embodiments, the reticulated reflective article 10 has a percent change in brightness depending on the amount of expansion of the reticulated reflective article 10. For example, as the reticulated reflective article 10 is expanded, brightness is decreased. In some embodiments, the reticulated reflective article 10 is expanded in area within a range of about 10% to at least about 300%. In some embodiments, the percent change in brightness from the non-expanded state of the reticulated reflective article 10 and an expanded version of the reticulated reflective article 10 is a percent reduction in brightness ranging from about 90% to even less than 40%. In some embodiments, the reticulated reflective article 10 provides a first reflective brightness when separated into a first width dimension between the plurality of strands 16 of reflective material 20 having an adhesive layer 28 (
In some embodiments, first width dimension is less than the second width dimension. In some embodiments, the first reflective brightness is higher than the second reflective brightness. In some embodiments, non-reflective regions of the reticulated reflective article 10 comprise at least 25% of the total surface area of the reflective material 20. In some embodiments, non-reflective regions of the reticulated reflective article 10 comprise at least 50% of the total surface area of the reflective material 20.
In some embodiments, the reticulated reflective article 10 can be described by the relation of one slit to another slit at least before the article is stretched. In some embodiments, the reticulated reflective article 10 can be described by the relation of one slit to another slit before the article is stretched and after the article is stretched and it has returned, at least in part, to its pre-stretched state. If not specified, any degree of overlap or lack thereof is referring at least to the degree of overlap that is measured before a reticulated reflective article has been stretched, e.g., in a pre-stretched state. Specifically, the degree of overlap of slits that are offset with respect to an axis perpendicular to the longitudinal dimension 12 (or offset with respect to an axis perpendicular to the width dimension).
Adjacent slits can have negative overlap, no overlap (e.g., they are at substantially the same point) or some degree of overlap.
In some embodiments, a reticulated retroreflective article can include a slit pattern having a dimension, n, that is not greater than 5 mm. Or stated another way, top and bottom points of any two adjacent (offset in an axis perpendicular to the longitudinal dimension) slits are not greater than 5 mm away from each other, as defined above. In some embodiments, a reticulated retroreflective article can include a slit pattern having a dimension, n, that is not greater than 3 mm. Or stated another way, top and bottom points of any two adjacent (offset in an axis perpendicular to the longitudinal dimension) slits are not greater than 3 mm from each other. In some embodiments, a reticulated retroreflective article can include a slit pattern having a dimension, n, that is not greater than 1 mm. Or stated another way, top and bottom points of any two adjacent (offset in an axis perpendicular to the longitudinal dimension) slits are not greater than 1 mm away from each other. In some embodiments, a reticulated retroreflective article can include a slit where the top and bottom points of adjacent slits can be 0 mm (or within manufacturing tolerances away) from the mid line, as defined above.
Referring now to
The presently disclosed reticulated reflective articles 10 have a first brightness when in a non-expanded form and a second brightness when in an expanded form. The presently disclosed reticulated reflective articles 10 have a first permeability when in a non-expanded form and a second permeability when in an expanded form. The presently disclosed reflective material 20 is selected from at least one of optical films, microprismatic film and microsphere films.
Referring now to
In some embodiments, the presently disclosed article 100 also includes a multitude 124 of the plurality of regions 116 extending radially from a common intersection 125. In some embodiments, the presently disclosed articles 100 provide a first reflective brightness when separated into a first width dimension between the plurality of regions 116 of reflective material 20 and a second reflective brightness when separated into a second width dimension between the plurality of regions 116 of reflective material 20.
In some embodiments, the reticulated reflective article 100 has a percent change in brightness depending on the amount of expansion of the reticulated reflective article 100. For example, as the reticulated reflective article 100 is expanded, brightness is decreased. In some embodiments, the reticulated reflective article 100 is expanded in area within a range of about 10% to at least about 300%. In some embodiments, the percent change in brightness from the non-expanded state of the reticulated reflective article 100 and an expanded version of the reticulated reflective article 100 is a percent reduction in brightness ranging from about 90% to even less than 40%. In some embodiments, the reticulated reflective article 100 provides a first reflective brightness when separated into a first width dimension between the plurality of regions 116 of reflective material 20 having an adhesive layer 28 disposed thereon and a second reflective brightness when separated into a second width dimension between the plurality of regions 116 of reflective material having an adhesive layer 28 disposed thereon. These varying brightnesses and permeabilities can be assessed before and/or after numerous washings of the reticulated reflective articles 100. In some embodiments, the change in open area from the first width dimension to the second width dimension is at least 20%, the reduction in brightness between the first reflective brightness and the second reflective brightness is from at least 25% reduction in brightness to about a 90% reduction in brightness, wherein both brightnesses are determined according to ASTM E810-03 (2013) when performed on unwashed reticulated reflective articles, and further wherein the reticulated reflective article has a permeability of at least 5.5 cm/s.
In some embodiments, the presently disclosed reticulated reflective articles 100 provide a first reflective brightness when separated into a first width dimension between the plurality of regions 116 of reflective material 20 having an adhesive layer 28 disposed thereon and a second reflective brightness when separated into a second width dimension between the plurality of regions 116 of reflective material 20 having an adhesive layer 28 disposed thereon. In some embodiments, the first reflective brightness is higher than the second reflective brightness.
Referring again to
In some embodiments, the presently disclosed reticulated reflective articles 100 have a first brightness when in a non-expanded form and a second brightness when in an expanded form. In some embodiments, the presently disclosed reticulated reflective articles 100 have a first permeability when in a non-expanded form and a second permeability when in an expanded form. These varying bfightnesses and permeabilities can be assessed after numerous washings of the reticulated reflective articles 100. In some embodiments, the useful reflective material 20 is selected from at least one of optical films, microprismatic film and microsphere films.
In some embodiments, the slits 11, 21, 31, perforations, or combinations theroef can be made using any known techniques, such as rotary die cutting, laser cutting, ultrasonic slitting, and the like.
The retroreflective articles of this disclosure can be incorporated into a wide variety of commercial articles to impart retroreflectivity to the commercial articles. Examples of suitable commercial articles include: display articles such as signs, billboards, pavement markings, and the like; transportation articles such as bicycles, motorcycles, trains, buses, and the like; and clothing articles such as shirts, sweaters, sweatshirts, jackets, coats, pants, shoes, socks, gloves. belts, hats, suits, one-piece body garments, vests, bags, and backpacks, and the like. Additional articles on which the presently disclosed reflective articles can be used include articles useful for camping gear, baby gear, pet accessories, toys, phone accessories, sport accessories, fashion accessories, and the like. The presently disclosed reflective articles can also be converted into logos, designs such as outlines, patterns, silhouettes, shapes, lines, patches, panels, notions (as example: piping, tape, buttons, binding, zippers, trim, lace) and the like.
Firefighter garments, and thus multi-layer firefighter outfits, can be greatly improved by implementing vapor permeable reflective material. If vapor cannot escape thought the outer shell because conventional reflective material provides a vapor barrier, hot vapors can be directed inward, toward the skin of the wearer, possibly causing steam burns or other discomfort to the wearer. The techniques described herein resolve this issue by providing a reflective material formed in a reticulated pattern to define reflective regions and non-reflective regions. In this manner, the addition of reflective material does not substantially decrease vapor permeability of the outer shell.
Thermal decay through an outer shell having conventional reflective trim material, such as perforated reflective trim material, is substantially less than thermal decay through the outer shell in regions not having the conventional reflective trim material. Thus, heat trapped within the protective garment may not be able to escape fast enough for the firefighter to cool off at a desired rate. Rather, the presence of conventional reflective material such as perforated reflective trim material can cause heat to remain trapped inside the protective garment for longer periods of time, providing discomfort to the firefighter even after he or she has left the fire. The techniques described herein resolve this issue by providing a non-continuous vapor permeable reflective material that does not substantially decrease thermal decay of the garment in the portions having the non-continuous vapor permeable reflective material. In this manner, the vapor permeable reflective material can reduce the heat load within the various layers that comprise the firefighter outfit, reduce negative physiological impacts on the wearer, and reduce the likelihood of producing burn injuries on the wearer.
The techniques described herein can provide reticulated vapor permeable reflective material having a reflective brightness greater than about 25 candelas/(lux*meter2) or even greater than 250 candelas/(lux*meter2). Brightnesses in these ranges significantly increase visibility of a wearer during nighttime and twilight hours. Indeed, this can better ensure that firefighters are not only seen by night motorists, but more importantly, these brightness ranges can be achieved while still providing the vapor permeability and thermal decay characteristics described above.
Following is a non-limiting disclosure of embodiments and combinations of embodiments of the presently disclosed reticulated reflective articles:
Embodiment 1. A reticulated reflective article, comprising:
a plurality of strands of a reflective material attached to one another at bridging regions in the reflective material and separable from one another between the bridging regions to provide openings in the reflective material, wherein the openings are expandable to provide a variably expandable area, and wherein the reflective materials comprises a reflective major surface and a non-reflective major surface,
wherein each of the openings has a longitudinal dimension, a width dimension, and each of the plurality of strands has a thickness, and
wherein the reticulated reflective article is expandable in at least one of a longitudinal direction and a width direction.
Embodiment 2. The article of Embodiment 1, wherein the article provides a first reflective brightness when separated into a first width dimension between the plurality of strands of reflective material and a second reflective brightness when separated into a second width dimension between the plurality of strands of reflective material.
Embodiment 3. The article of Embodiment 2, wherein the reduction in brightness between the first reflective brightness and the second reflective brightness is from at least about 10% reduction in brightness to about a 90% reduction in brightness, wherein both brightnesses are determined according to ASTM E810-03 (2013) when performed on unwashed reticulated reflective articles.
Embodiment 4. The article of Embodiment 2, wherein the change in open area from the first width dimension to the second width dimension is at least 20%, the reduction in brightness between the first reflective brightness and the second reflective brightness is from at least 25% reduction in brightness to about a 90% reduction in brightness, wherein both brightnesses are determined according to ASTM E810-03 (2013) when performed on unwashed reticulated reflective articles, and further wherein the reticulated reflective article has a permeability of at least 5.5 cm/s.
Embodiment 5. The article of Embodiment 2, wherein the article provides a first reflective brightness when separated into a first width dimension between the plurality of strands of reflective material having an adhesive layer disposed thereon and a second reflective brightness when separated into a second width dimension between the plurality of strands of reflective material having an adhesive layer disposed thereon.
Embodiment 6. The article of Embodiments 3 and 4, wherein the first width dimension is less than the second width dimension.
Embodiment 7. The article of Embodiment 6, wherein the first reflective brightness is higher than the second reflective brightness.
Embodiment 8. The article of Embodiment 1, wherein non-reflective regions comprise at least 25% of the total surface area of the reflective material.
Embodiment 9. The article of Embodiment 1, wherein non-reflective regions comprise at least 50% of the total surface area of the reflective material.
Embodiment 10. The article of Embodiment 1, further comprising a carrier tape adhered to the reflective major surface of the reflective material.
Embodiment 11. The article of Embodiment 1 further comprising an adhesive layer disposed on one of the major surfaces of the reflective material, wherein the adhesive layer is separable into a plurality of strands disposed on the plurality of strands of the reflective material.
Embodiment 12. The article of Embodiment 2, further comprising a substrate disposed on a major surface of the adhesive layer opposite the reticulated reflective article.
Embodiment 13. The article of Embodiment 12, wherein the substrate is elastometic.
Embodiment 14. The article of Embodiment 12, wherein the article has a first brightness when it is in a non-expanded form and a second brightness when it is in an expanded form.
Embodiment 15. The article of Embodiment 12, wherein the article has a first permeability when it is in a non-expanded form and a second permeability when it is in an expanded form.
Embodiment 16. The article of any of the preceding Embodiments, wherein the reflective material is selected from at least one of optical films, microprismatic film and microsphere films.
Embodiment 17. A reticulated reflective article, having a longitudinal direction and a width direction, and comprises:
a plurality of regions of a reflective material separable from one another to provide openings in the reflective material, wherein the reflective materials comprises a reflective major surface and a non-reflective major surface,
wherein each of the openings has a longitudinal dimension, and a width dimension, and
wherein the reticulated reflective article is expandable in at least two directions.
Embodiment 18. The article of Embodiment 17 further comprising a multitude of the plurality of regions extending radially from a common intersection.
Embodiment 19. The article of Embodiments 17 or 18, wherein the article provides a first reflective brightness when separated into a first width dimension between the plurality of regions of reflective material and a second reflective brightness when separated into a second width dimension between the plurality of regions of reflective material.
Embodiment 20. The article of Embodiment 19, wherein the reduction in brightness between the first reflective brightness and the second reflective brightness is from about 10% reduction in brightness to about a 90% reduction in brightness, wherein both brightnesses are determined according to ASTM E810-03 (2013) when performed on unwashed reticulated reflective articles.
Embodiment 21. The article of Embodiment 19, wherein the change in open area from the first width dimension to the second width dimension is at least 20%, the reduction in brightness between the first reflective brightness and the second reflective brightness is from at least 25% reduction in brightness to about a 90% reduction in brightness, wherein both brightnesses are determined according to ASTM E810-03 (2013) when performed on unwashed reticulated reflective articles, and further wherein the reticulated reflective article has a permeability of at least 5.5 cm/s.
Embodiment 22. The article of Embodiment 19, wherein the article provides a first reflective brightness when separated into a first width dimension between the plurality of regions of reflective material having an adhesive layer disposed thereon and a second reflective brightness when separated into a second width dimension between the plurality of regions of reflective material having an adhesive layer disposed thereon.
Embodiment 23. The article of Embodiment 21, wherein the first reflective brightness is higher than the second reflective brightness.
Embodiment 24. The article of Embodiment 17, further comprising a carrier tape adhered to the reflective major surface of the reflective material.
Embodiment 25. The article of Embodiment 17 further comprising an adhesive layer disposed on one of the major surfaces of the reflective material, wherein the adhesive layer is separable into a plurality of regions disposed on the plurality of regions of the reflective material.
Embodiment 26. The article of Embodiment 19, further comprising a substrate disposed on a major surface of the adhesive layer opposite the reticulated reflective article.
Embodiment 27. The article of Embodiment 17, wherein the substrate is elastomeric.
Embodiment 28. The article of Embodiment 25, wherein the article has a first brightness when it is in a non-expanded form and a second brightness when it is in an expanded form.
Embodiment 29. The article of Embodiment 25, wherein the article has a first permeability when it is in a non-expanded form and a second permeability when it is in an expanded form.
Embodiment 30. The article of any of Embodiments 17 to 29, wherein the reflective material is selected from at least one of optical films, microprismatic film and microsphere films.
Embodiment 31. A reflective article having at least a longitudinal dimension and a width dimension, the article comprising:
a reflective layer comprising optical film, microprismatic film, microsphere film, or combinations thereof having a plurality of slits formed therein, the plurality of slits having a slit direction and each slit having a top and an opposing bottom direction along the slit direction, the slit direction being at least substantially parallel to the longitudinal dimension or the width dimension, the plurality of slits comprising at least two adjacent slits offset with respect to an axis perpendicular to the slit direction, wherein the top of and bottom of at least two adjacent slits are not greater than 5 mm apart along the slit direction when the reflective article is in a pre-stretched condition.
This invention is 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 disclosure.
Retroreflectivity for the examples was measured using the test criteria described in ASTM E810-03 (2013)—Standard Test Method for Coefficient of Retroreflection of Retroreflective Sheeting Utilizing the Coplanar Geometry. Results, measured as retroreflective units Ra, which represents the units of cd/lux/m2.
The % open area for each of the expanded/reticulated films was determined mathematically by dividing amount of expansion by final width of the expanded/reticulated films.
Wash durability was measured following ISO 6330 Method 2A (60 C home wash). Retroreflectivity was measured before washing, and after 75 wash cycles. Results, measured as reflective units Ra, which represents the units of cd/lux/m2.
Air permeability was measured following ASTM D737-04 (2016)—Standard Test Method for Air Permeability of Textile Fabrics. Results are reported as cm/s (cfm/sq ft).
Methods for Preparing Slit and Expanded/Reticulated Reflective Films
Slit reflective film can be prepared any of a number of ways, including rotary die cutting and laser cutting. The slit films described in the Examples below were made by rotary die cutting 5 cm (2 inch) wide reflective material available under the trade designation “3M Scotchlite 8725 Silver Transfer Film” from 3M Company, St. Paul, Minn. Openings were cut in the transfer film with a straight opening shape, a 22 mm longitudinal repeat with one opening per repeat in the longitudinal direction and 2 openings per width repeat.
Alternatively, reflective material commercially available under the trade designation “3M Scotchlite 8725 Silver Transfer Film” can be slit via laser cutting system, using a laser cutter commercially available under the trade designation “Mini FlexPro Model LB2440” from Preco Incorporated, Lenexa, Kans., with a 400 watt CO2, 9.36 nm wavelength resonator. Power settings were 40 to 60% in pulsed mode. The laser ablated an array of slits approx. 200 microns wide.
The expanded/reticulated films described in the Examples below were made using a manual expanding/spreading process to expand the die cut or laser cut films. Alternatively, expanded/reticulated films may be made via an automated process using a nip roll equipped with a spreader bar. The extent of spreading is controlled by the deflection of the spreader bar against the slit film, the degree of curvature of the spreader, and the tension of slit film. The spread/reticulated film material is then passed over a high traction nip roll where the spread/reticulated configuration is held, and then the film is laminated to a release liner (such as that commercially available under trade designation “8403” from 3M Company, St. Paul. Minn.) and wound onto a 7.6 cm (3 inch) cardboard core. The films are not limited to expansion in longitudinal or width directions only, and in certain configurations can be expanded radially or multi-directionally.
Example 1 describes a slit film without expansion/reticulation, produced by laminating a manually assembled retroreflective film to a woven fabric or substrate with an adhesive layer. The slit reflective film was made by rotary die cutting 5 cm (2 inch) wide reflective film, commercially available under the trade designation “3M Scotchlite 8725 Silver Transfer Film” from 3M Company, St. Paul, Minn. Openings were cut in the transfer film with a straight opening shape, a 22 mm longitudinal repeat with one opening per repeat in the longitudinal direction and 2 openings per width repeat. Openings were separated by strand width of 2 mm/2 mm. The bridge regions longitudinal directions were 2 mm/2 mm with the bridge regions offset 0%/50%. After slitting lined products, the paper liner was removed (manually or with a winder roll to strip the liner) and replaced with a release liner commercially available under the trade designation “3M Polyester 8403” from 3M Company on the beaded side. The slit film was then heat laminated to a twill weave polyester fabric such as that commercially available under the trade designation “Lauffenmüle fabric (#42040, 65% polyester/35% cotton, 215 g″m2, color: Bugatti Royal #40228/2)” from Lauffenmüle Textil GmbH, Lauchingen, Germany. Lamination was done using a transfer press such as that commercially available under the trade designation “Stahls' Hotronix Thermal Transfer Press STX20” from Stahls' Hotronix, Carmichaels, Pa. at 177 C (350 F) for a dwell time of 20 seconds at an airline pressure setting of 4.
After the sample cooled to room temperature, the release liner was removed, yielding a reticulated retroreflective article.
The reticulated and fabric laminated samples were tested according to Test Method for Measuring Wash Durability and Test Method for Measuring Air Permeability, described above, with values for Brightness (Ra) and Permeability given in Table 1.
Values of opening shape, repeat longitudinal direction [mm], number of openings longitudinal repeat, number of openings width repeat, strand width [mm], bridge regions longitudinal direction [mm], bridge region offset [%], and variation from standard are given in Tables 2 and 3. Example 1 corresponds to
Example 2 was prepared by slitting the film as in Example 1, and then expanding/reticulating to approximately 24% open area. The slit film of Example 1 was manually expanded by placing the slit film with bead side up and securing the ends of the film to a flat surface with masking tape, such as that commercially available under the trade designation “3M Industrial Masking Tape” from 3M Company, to keep the slit film flat and straight. The bottom edge of the film was secured to a flat surface placing the tape parallel to the slit openings at a desired film edge width. A rigid low profile flat spreader bar (e.g. ruler), used to spread the film, was secured to the top of the slit film. Short edges were trimmed. The spreader bar was pulled in a direction perpendicular in the plane to the slit direction, to expand the film to the desired spread distance.
The expanded film was secured along the top of the spreader bar edge with masking tape. A release liner, such as that commercially available under the trade designation “3M Polyester Tape 8403” from 3M Company, was then applied to the top (bead side) of the film and rolled down flat with a rubber roller to adhere the expanded configuration to the transfer film. The expanded reticulated film material was then heat laminated as in Example 1.
After the sample cooled to room temperature, the release liner was removed, yielding a reticulated expanded reflective article. The sample was thereafter laminated and tested as Example 1,
Example 3 was prepared by slitting the film as in Example 1, and then expanding/reticulating as in Example 2, to an open area of approximately 60% followed by laminating and testing as Example 1.
Comparative Example C1 consists of 5 cm (2 inch) wide transfer film, such as that commercially available under the trade designation “3M Scotchlite 8725 Silver Transfer Film” from 3M Company, laminated and tested as described in Example 1 except that no carrier tape was present.
Comparative Example C2 consists of 5 cm (2 inch) wide reflective material, such as that commercially available under the trade designation “3M Scotchlite Reflective Material 5510 Segmented Home Wash Trim” from 3M Company, laminated and tested as Example 1. Comparative Example 2 is created using a technique different than the technique used for Examples 1 to 3 because for Comparative Example 2 is created by using a continuous sheet of the reflective material, cutting out portions and then removing them. It is not an expandable reflective material.
A number of implementations and embodiments have been described. For instance, reticulated vapor permeable reflective material having reflective regions and non-reflective regions has been described. Thermal decay and vapor permeability through the reticulated vapor permeable reflective material is substantially the same as thermal decay and vapor permeability through the underlying material that does not include reticulated vapor permeable reflective material.
Nevertheless, it is understood that various modifications can be made without departing from the spirit and scope of this disclosure. For example, the reticulated vapor permeable reflective material could be included in as part of any garment to provide reflectively in the garment and yet also provide adequate thermal decay and vapor permeability through the garment. In addition, the reticulated vapor permeable reflective material could substantially or completely cover a garment or article. Also, the reflective material may be made florescent to enhance daytime visibility. In addition, alternative methods may be used to realize reticulated vapor permeable reflective material. For example, various different graphic screen printing techniques, electronic digital printing techniques, plotter cutting, laser cutting, or die cutting of reflective substrates to be applied on a material, or other similar techniques may be used to realize reticulated vapor permeable reflective material. Accordingly, other implementations and embodiments are within the scope of the following claims.
This disclosure claims priority to U.S. Provisional Application No. 62/382,469 entitled. RETICULATED REFLECTIVE MATERIAL, filed on Sep. 1, 2016, the disclosure of which is incorporated herein by reference thereto.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2017/049906 | 9/1/2017 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62382469 | Sep 2016 | US |
