Patent Application
20160311080
The present invention relates to the field of abrasives, in particular to an abrasive, an abrasive article and a method for preparing an abrasive article.
In the production process of LCD panels, there is a step of cleaning the LCD panel surface. In this step, a scraping knife or an abrasive band is generally used to remove impurities or glass debris from the LCD panel surface.
However, the scraping knife cannot be used to clean an LCD panel surface having ITO (transparent and conductive indium-tin oxide film) coating, as it would scratch the ITO coating. Conventional abrasive bands used to clean the ITO coating on an LCD panel surface mainly comprise aluminum oxide abrasive particles which may scratch on the ITO coating, thus affecting the yield rate of LCD panels.
Therefore, there is a need to develop a novel abrasive and a novel abrasive article, which can be used to clean an LCD panel surface without scratching the ITO coating on the LCD panel surface.
It is an object of the present invention to provide a novel abrasive and an abrasive article having a relatively low wear resistance, the abrasive article can be used to clean an LCD panel surface without scratching the ITO coating on the LCD panel surface.
According to an aspect of the present invention, an abrasive comprising abrasive particles and an adhesive matrix is provided, with the abrasive particles being distributed in the adhesive matrix, wherein the abrasive particles comprise aluminum hydroxide abrasive particles, and the adhesive matrix comprises a triacrylate, a diacrylate and an initiator.
According to certain preferred embodiments of the present invention, the aluminum hydroxide abrasive particles have an average particle size of 0.5 to 10 μm.
According to certain preferred embodiments of the present invention, the aluminum hydroxide abrasive particles are present in an amount of 15 to 30 wt. %, based on the total weight of the abrasive as 100 wt. %.
According to certain preferred embodiments of the present invention, the abrasive particles may further comprise calcium carbonate abrasive particles.
According to certain preferred embodiments of the present invention, the calcium carbonate abrasive particles have an average particle size of 0.5 to 5 μm.
According to certain preferred embodiments of the present invention, the calcium carbonate abrasive particles are present in an amount of 0.5 to 5 wt. %, based on the total weight of the abrasive as 100 wt. %.
According to certain preferred embodiments of the present invention, the abrasive particles further comprise aluminum oxide abrasive particles.
According to certain preferred embodiments of the present invention, the aluminum oxide abrasive particles have an average particle size of 0.5 to 5 μm.
According to certain preferred embodiments of the present invention, the aluminum oxide abrasive particles are present in an amount of 0.5 to 2 wt. %, based on the total weight of the abrasive as 100 wt. %.
According to certain preferred embodiments of the present invention, the adhesive matrix is present in an amount of 60 to 85 wt. %, based on the total weight of the abrasive as 100 wt. %.
According to certain preferred embodiments of the present invention, the triacrylate has an average molecular weight of 150 to 500.
According to certain preferred embodiments of the present invention, the triacrylate is selected from one or more from the group consisting of an isocyanurate-acrylate and a trimethylolpropanetriacrylate.
According to certain preferred embodiments of the present invention, the triacrylate is present in an amount of 10 to 40 wt. %, based on the total weight of the abrasive as 100 wt. %.
According to certain preferred embodiments of the present invention, the diacrylate has an average molecular weight of 100 to 600.
According to certain preferred embodiments of the present invention, the diacrylate is selected from one or more from the group consisting of a polyethylene glycol (200) diacrylate and an oxyethylene bisphenol A diacrylate.
According to certain preferred embodiments of the present invention, the diacrylate is present in an amount of 30 to 60 wt. %, based on the total weight of the abrasive as 100 wt. %.
According to certain preferred embodiments of the present invention, the initiator is present in an amount of 0.1 to 5 wt. %, based on the total weight of the abrasive as 100 wt. %.
According to certain preferred embodiments of the present invention, the adhesive matrix may further comprise one or more from the group consisting of a surfactant, a suspending agent, a coupling agent or a dispersing agent.
According to another aspect of the present invention, an abrasive article is provided, comprising the cured abrasive provided according to the present invention.
According to certain preferred embodiments of the present invention, the abrasive article comprises one protruding member or a plurality of protruding members.
According to certain preferred embodiments of the present invention, the shape of the cross section of the protruding member in the horizontal direction comprises one or more from the group consisting of a triangle, a square, a rectangle, a lozenge, a pentagon, a hexagon, a circle and an ellipse.
According to certain preferred embodiments of the present invention, the upper surface of the protruding member is parallel to the cross section of the protruding member in the horizontal direction.
According to certain preferred embodiments of the present invention, the protruding member is of a pyramid structure.
According to certain preferred embodiments of the present invention, the protruding member has a height of 10 to 500 μm.
According to certain preferred embodiments of the present invention, the plurality of protruding members are of the same height.
According to certain preferred embodiments of the present invention, the plurality of protruding members are regularly arranged.
According to certain preferred embodiments of the present invention, the abrasive article further comprises a backing layer on which the protruding members are disposed.
According to certain preferred embodiments of the present invention, the material for the backing layer comprises one or more from the group consisting of polyethylene film, polyester cloth, blended cloth, cotton cloth and paper.
According to certain preferred embodiments of the present invention, a primer coating layer is included between the protruding members and the backing layer.
According to certain preferred embodiments of the present invention, the material for the primer coating layer comprises one or more from the group consisting of polyurethane and ethylene/acrylic acid copolymer.
According to another aspect of the present invention, a method for preparing an abrasive article is provided, comprising the step of curing the abrasive provided according to the present invention.
According to certain preferred embodiments of the present invention, the abrasive can be cured by ultraviolet light.
According to certain preferred embodiments of the present invention, the strength of the ultraviolet light is from 500 to 700 watts/decimeter, preferably 600 watts/decimeter.
According to certain preferred embodiments of the present invention, the abrasive provided according to the present invention can firstly be disposed onto the backing layer prior to the step of curing the abrasive. Preferably, the abrasive provided according to the present invention can be disposed on the backing layer by coating application.
According to certain preferred embodiments of the present invention, the material for the backing layer comprises one or more from the group consisting of polyethylene film, polyester cloth, blended cloth, cotton cloth and paper.
According to certain preferred embodiments of the present invention, a primer coating layer is firstly disposed on the backing layer prior to the step of disposing the abrasive on the backing layer.
According to certain preferred embodiments of the present invention, the material for the primer coating layer comprises one or more from the group consisting of polyurethane and ethylene/acrylic acid copolymer.
The abrasive article provided according to the present invention has a relatively low wear resistance and can be used to clean an LCD panel surface without scratching the ITO coating on the LCD panel surface.
The above summary is not intended to describe each disclosed embodiment of every implementation of the present invention. The features and advantages of the above and further embodiments of the present invention become more apparent from the more detailed illustration of the exemplary embodiments of the present invention in the detailed description set forth below, when taken in conjunction with the drawings.
It is to be understood that various other embodiments can be contemplated and modifications thereof can be made by those skilled in the art in light of the teachings of the present specification without departing from the scope or spirit of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense.
Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein. The recitation of numerical ranges by endpoints comprises all numbers subsumed within that range and any range within that range. For example, 1, 2, 3, 4 and 5 include 1, 1.1, 1.3, 1.5, 2, 2.75, 3, 3.80, 4, and 5, etc.
The present invention provides an abrasive which can be cured to obtain an abrasive article having a relatively low wear resistance and can be used to clean an LCD panel surface without scratching the ITO coating on the LCD panel surface.
The abrasive provided by the present invention comprises abrasive particles and an adhesive matrix, with the abrasive particles being distributed in the adhesive matrix, wherein the abrasive particles comprise aluminum hydroxide abrasive particles, and the adhesive matrix comprises a triacrylate, a diacrylate and an initiator.
The aluminum hydroxide abrasive particles have an average particle size of 0.5 to 10 μm, preferably 0.5 to 5 μm, more preferably 0.5 to 1 μm. The aluminum hydroxide abrasive particles are present in an amount of 15 to 30 wt. %, preferably 25 to 30 wt. %, based on the total weight of the abrasive as 100 wt. %.
The abrasive particles may further comprise calcium carbonate abrasive particles. The calcium carbonate abrasive particles have an average particle size of 0.5 to 5 μm, preferably 1 to 3 μm. The calcium carbonate abrasive particles are present in an amount of 0.5 to 5 wt. %, preferably 1 to 5 wt. %, based on the total weight of the abrasive as 100 wt. %.
The abrasive particles may further comprise aluminum oxide abrasive particles. The aluminum oxide abrasive particles have an average particle size of 0.5 to 5 μm, preferably 1 to 3 μm. The aluminum oxide abrasive particles are present in an amount of 0.5 to 2 wt. %, preferably 1 to 2 wt. %, based on the total weight of the abrasive as 100 wt. %.
The adhesive matrix is present in an amount of 60 to 85 wt. %, based on the total weight of the abrasive as 100 wt. %.
The triacrylate has an average molecular weight of 150 to 500, preferably 200 to 500. The triacrylate can preferably be selected from one or more from the group consisting of an isocyanurate-acrylate and a trimethylolpropanetriacrylate. For example, the triacrylate isocyanurate-acrylate SR368D or trimethylolpropanetriacrylate SR351 commercially available from Sartomer Corp. can be selected. The triacrylate is present in an amount of 10 to 40 wt. %, based on the total weight of the abrasive as 100 wt. %. The triacrylate can be used to enhance the adhesive performance of the adhesive matrix so that the abrasive particles are bonded in the adhesive matrix. Moreover, the triacrylate can further be used to bond the abrasive and the backing layer together. Additionally, the triacrylate helps the curing of the abrasive to form the abrasive article (refer to the “Abrasive article” section of the present specification for the description of the “abrasive article”). If the abrasive lacks the triacrylate, the adhesive matrix will be so soft that the abrasive will fail to cure to form the abrasive article.
The diacrylate has an average molecular weight of 100 to 600, preferably 200 to 600. The diacrylate can be selected from one or more from the group consisting of a polyethylene glycol (200) and an oxyethylene bisphenol A diacrylate. For example, the polyethylene glycol (200) diacrylate SR259 or oxyethylene bisphenol A diacrylate SR601 commercially available from Sartomer Corp. can be selected. The diacrylate is present in an amount of 30 to 60 wt. %, based on the total weight of the abrasive as 100 wt. %. The diacrylate helps to allow the abrasive article formed after curing of the abrasive to have a relatively low wear resistance, such that no scratches would be produced on the ITO coating on the LCD panel surface. If the abrasive lacks the diacrylate, the abrasive matrix will be so hard that the wear resistance of the abrasive article formed after curing of the abrasive will be too high, such that scratches would be produced on the ITO coating on the LCD panel surface. Moreover, the diacrylate may also help to increase the hydrophilicity of the abrasive, so that the abrasive article formed after curing of the abrasive has a proper wear resistance under the condition of water abrasion. This can better control the wear rate of the abrasive article, such that the abrasive article would wear neither too fast nor too slow. If the abrasive article wears too fast, its service life would be shortened, and if too slow, scratches would be produced on the ITO coating on the LCD panel surface.
The initiator can facilitate the curing of the abrasive, not only allowing the abrasive particles to be bonded in the adhesive matrix, but also allowing the abrasive and the backing layer to be bonded together. The initiator can preferably be selected from one or more from the group consisting of a photoinitiator or a thermal radical initiator. The photoinitiator can preferably be selected from one or more from the group consisting of an ultraviolet initiator and a light-activated initiator, more preferably an ultraviolet initiator. For the ultraviolet initiator, Irgacure 819 commercially available from Ciba Corp. can for example be selected, and for the light-activated initiator, the TPO-L commercially available from Basf Corp. can for example be selected. For the thermal radical initiator, VAZO 52 or VAZO67 commercially available from Dupont Corp. can for example be selected. The initiator is present in an amount of 0.1 to 5 wt. %, based on the total weight of the abrasive as 100 wt. %.
The adhesive matrix may further comprise one or more from the group consisting of a surfactant, a suspending agent, a coupling agent, and a dispersing agent.
The surfactant can be used to improve the bonding strength and affinity between the adhesive matrix and the backing. The surfactant can preferably be selected from one or more from the group consisting of an ionic surfactant, a cationic surfactant and a nonionic surfactant, more preferably a nonionic surfactant. The nonionic surfactant is preferably an alcohol ether surfactant. For the alcohol ether surfactant, Tergitol 15-S-5 commercially available from Dupont Corp. can, for example, be selected. The surfactant is present in an amount of 0.1 to 10 wt. %, based on the total weight of the abrasive as 100 wt. %.
The suspending agent can be used to reduce the precipitation of the abrasive particles in the adhesive matrix. The suspending agent can preferably be amorphous silicon oxide particles, more preferably amorphous silicon oxide particles having a surface area of less than 150 m2/g. For the amorphous silicon oxide particles having a surface area of less than 150 m2/g, the OX50 commercially available from Evonik Corp. can, for example, be selected. The suspending agent is present in an amount of 1 to 5 wt. %, preferably 1 to 2 wt. %, based on the total weight of the abrasive as 100 wt. %.
The coupling agent can provide association bridges between the adhesive matrix and the abrasive particles. The coupling agent can preferably be selected from one or more from the group consisting of a silane coupling agent, a titanate coupling agent, and a zirconium aluminate coupling agent. The coupling agent can be added in different manners as desired. For example, the coupling agent can be directly added into the adhesive matrix. The coupling agent is preferably in an amount of 0.1 to 5 wt. %, more preferably 0.1 to 3 wt. %, based on the total weight of the abrasive as 100 wt. %.
The dispersing agent can be used to reduce the viscosity of the adhesive matrix so that the abrasive particles are evenly distributed in the adhesive matrix. The dispersing agent can preferably be an anchoring polymer dispersing agent. For the anchoring polymer dispersing agent, the Solplus D520 commercially available from Lubrizol Corp. can, for example, be selected. The dispersing agent is present in an amount of 0.1 to 0.5 wt. %, preferably 0.1 to 0.3 wt. %, based on the total weight of the abrasive as 100 wt. %.
The abrasive provided by the present invention has a relatively low wear resistance and can be used to clean an LCD panel surface without scratching the ITO coating on the LCD panel surface.
The present invention further provides an abrasive article. The abrasive article comprises an abrasive layer comprising the cured abrasive provided by the present invention. Refer to the “Abrasive” section of the present specification for the description of the “abrasive”.
As shown in
The material for the backing layer 110 can preferably be selected from one or more from the group consisting of polyethylene backing, polyester cloth backing, blended cloth backing, cotton cloth backing and paper backing, more preferably polyethylene backing. For example, the polyethylene backing commercially available from 3M Corp. can be selected.
The shape of the cross section of the protruding members 120 in the horizontal direction can preferably be selected from one or more from the group consisting of a triangle, a square, a rectangle, a lozenge, a pentagon, a hexagon, a circle and an ellipse, more preferably a square, a rectangle and an ellipse. The area of the cross section of the protruding members 120 in the horizontal direction can preferably be 0.25 to 5 mm2, more preferably 1 to 3 mm2
The upper surface of the protruding members 120 can be parallel or unparallel to the cross section of the protruding members 120 in the horizontal direction. Preferably, the upper surface of the protruding members 120 is parallel to the cross section of the protruding members 120 in the horizontal direction. The shape of the upper surface of the protruding members 120 can be the same as or different from that of the cross section of the protruding members 120 in the horizontal direction. Preferably, the shape of the upper surface of the protruding members 120 is the same as that of the cross section of the protruding members 120 in the horizontal direction. The area of the upper surface of the protruding members 120 can be the same as or different from that of the cross section of the protruding members 120 in the horizontal direction. Preferably, the area of the upper surface of the protruding members 120 is the same as that of the cross section of the protruding members 120 in the horizontal direction.
Moreover, the protruding members 120 can be of a pyramid structure. The height of the protruding members 120 is represented by h1, and preferably h1=10 to 500 μm, and more preferably h1=200 to 350 μm.
If the abrasive article 100 comprises a plurality of protruding members 120, the height hi of these protruding members 120 can be the same or different. Preferably, the height h1 of the protruding members 120 is the same, which helps the abrasive article to clean an LCD panel surface without scratching the ITO coating on the LCD panel surface.
If the abrasive article 100 comprises a plurality of protruding members 120, these protruding members 120 can be regularly or irregularly arranged. Preferably, these protruding members 120 are regularly arranged, which helps the abrasive article to clean an LCD panel surface without scratching the ITO coating on the LCD panel surface.
The abrasive article 100 can further comprise a primer coating layer 130 (not shown in the figure). The primer coating layer 130 can be used to increase the bonding force between the backing layer 110 and the protruding members 120. The material for the primer coating layer 130 can be selected from one or more from the group consisting of polyurethane and ethylene acrylic acid copolymer, more preferably ethylene acrylic acid copolymer.
The present invention provides a method for preparing an abrasive article, comprising the step of curing the abrasive provided according to the present invention.
Refer to the “Abrasive” section of the present specification for the description of the “abrasive”.
As shown in
As shown in
Preferably, the side walls of the cavities 220 are perpendicular to the bottom surface.
Preferably, the bottom surface of the cavities 220 is parallel to the cross section of the cavities 220 in the horizontal direction. Preferably, the shape of the bottom surface of the cavities 220 is the same as that of the cross section of the cavities 220 in the horizontal direction. Preferably, the area of the bottom surface of the cavities 220 is the same as that of the cross section of the cavities 220 in the horizontal direction.
Moreover, the cavities 220 can be of an inverted pyramid structure. The depth of the cavities 220 is represented by b1, and preferably b1=10 to 500 μm, and more preferably b1=200 to 350 μm. If the mould 200 comprises a plurality of cavities 220, the depth b1 of these cavities 220 can be the same or different. Preferably, the depth b1 of these cavities 220 is the same. If the mould 200 comprises a plurality of cavities 220, these cavities 220 can be regularly or irregularly arranged. Preferably, these cavities 220 are regularly arranged.
In the step of curing the abrasive, if the abrasive comprises a photoinitiator, the abrasive can preferably be cured by ultraviolet light. When ultraviolet light is used to cure the abrasive, the intensity of the ultraviolet light is 500 to 700 watts/decimeter, preferably 600 watts/decimeter.
In the step of curing the abrasive, if the abrasive comprises a thermal radical initiator, the abrasive can preferably be cured by heating, the heating temperature preferably being 50 to 120° C.
The examples and comparative examples provided below are intended to aid in understanding the present invention and should not be construed as limiting the scope of the present invention. All parts and percentages are by weight, unless otherwise specified.
The raw materials used in the examples and comparative examples of the present invention are as shown in Table 1 below.
The wear resistance performance of the abrasive articles provided in the examples and comparative examples of the present invention was mainly evaluated by the “Schiefer Test” shown in
An abrasive article was cut into a round disc (as shown in
The pre-test disc was subjected to a 3D detection using a digital microscope VHX-1000 E (commercially available from Keyence Corp.) and the thickness of the pre-test disc was recorded.
As shown in
At a test pressure of 4.54 kg and under the condition of wet abrasion with continuous water jet (the flow rate of water 350 was 30 ml/min), a ring 340 made of PMMA (polymethyl methacrylate) and having an outer diameter of 102 mm and an internal diameter of 51 mm was abraded using the disc 330, with a total of 4,500 revolutions. During the test, the rotation speed of the tray 320 was 250 rpm, the rotation speed of the PMMA ring 340 was 250 rpm, and the rotation direction of the PMMA ring 340 was the same as that of the tray 320. The arrows in
Upon completion of the abrading, the disc 330 was blow dried. The post-test disc was subjected to a 3D detection using the digital microscope VHX-1000 E (commercially available from Keyence Corp.), and the thickness of the post-test disc was recorded. The actual wear of the abrasive article was calculated according to the following formula to evaluate the wear resistance rate of the abrasive article:
Actual wear=Thickness of the disc prior to abrading−Thickness of the disc upon completion of the abrading
If the actual wear of the disc was less than 5 μm, then the disc has a relatively high wear resistance and, if the disk is used to clean an LCD panel surface, it would scratch the ITO layer on the LCD panel surface. If the actual wear of the disc was greater than or equal to 5 μm, then the disc (abrasive article) has a relatively low wear resistance and, if the disk is used to clean an LCD panel surface, it would not scratch the ITO layer on the LCD panel surface.
The test results of the wear resistance performance of the abrasive articles provided by the examples and comparative examples of the present invention are listed in Table 4.
Adhesive matrix was prepared by the following steps using the components and amounts thereof listed in Table 2.
Step 1: The components were added into a CA Model #LA1A stirrer (commercially available from Cott Turbon Mixer Inc.).
Step 2: The components were stirred under a temperature of 30° C. and a rotation speed of 400 rpm to mix well to obtain the adhesive matrix.
“Preparation of an Abrasive”:
An abrasive was prepared by the following steps using the components and amounts thereof listed in Table 3:
Abrasive particles were evenly dispersed into the adhesive matrix to obtain the abrasive using the CA Model #LA1A stirrer (commercially available from Cott Turbon Mixer Inc.) under a temperature of below 30° C. and a rotation speed of 400 rpm.
“Preparation of an Abrasive Article”:
The abrasive was evenly applied onto a PP (polypropylene) mould as shown in
According to the method provided in U.S. Pat. No. 5,975,987, the mould filled with the abrasive was applied onto a PET film which was coated with EAA (ethylene acrylic acid copolymer) elastic primer (alternatively, the mould filled with the abrasive can be applied onto a cloth backing which has a width of 12 inches and a thickness of 0.005 inch and which is coated with polyurethane primer).
According to the method provided in U.S. Pat. No. 5,975,987, under the conditions of a clamp force of 90 lbs/ft (approximately equal to 620.5 kPa) of the clamp rolls and a moving speed of 10 ft/min of the PET film, the abrasive on the PET film was irradiated with ultraviolet light having a intensity of 600 watts/decimeter (the equipment for ultraviolet light irradiation was EPIQ 6000, which is commercially available from Fusion System Corp., Gaithersburg, Md.).
After the abrasive is cured, the PP mould was separated from the PET film, resulting in a cured abrasive article formed on the PET film coated with EAA. The abrasive article had a width of 200 mm. The abrasive article had regularly arranged protruding members. The shape of the cross section of these protruding members in the horizontal direction was square (the sides of the square were 1.3 mm and the area was 1.69 mm2) These protruding members had a height h1 of 300±50 μm.
“Schiefer Test of Abrasive Articles”
A layer of 3M PSA 300LSE pressure-sensitive adhesive (commercially available from 3M Corp.) was applied on the backside of an abrasive article.
The abrasive article coated with pressure-sensitive adhesive was cut into a round disc with a diameter of 4 inches (as shown in
The actual wear of the disc was detected according to the “Schiefer Test method” provided in the “Schiefer Test” section of the present specification. The results are listed in Table 3.
It can be seen from comparative examples C1 to C3 that when the abrasive contained no aluminum hydroxide abrasive particles, the abrasive articles prepared from the abrasive had an actual wear of less than 5 μm, indicating that the abrasive articles had a relatively high wear resistance and would possibly scratch the ITO coating on an LCD panel surface.
It can be seen from comparative example C4 that when the abrasive contained aluminum hydroxide abrasive particles but contained no diacrylate, the abrasive article prepared from the abrasive had an actual wear of less than 5 μm, indicating that the abrasive article had a relatively high wear resistance and would possibly scratch the ITO coating on an LCD panel surface.
It can be seen from examples 5 to 13 that when the abrasive contained aluminum hydroxide abrasive particles, diacrylate and triacrylate, the abrasive articles prepared from the abrasive had an actual wear of greater than 5 μm, indicating that the abrasive articles had a relatively low wear resistance and would not scratch the ITO coating on an LCD panel surface.
Moreover, it can be seen from examples 10 and 12 that when the abrasive particles of the abrasive contained aluminum hydroxide abrasive particles, a suitable amount (1 to 2 wt. %) of calcium carbonate abrasive particles can be further added to the abrasive particles, and the abrasive articles prepared from such an abrasive had an actual wear of greater than 5 μm, indicating that the abrasive articles had a relatively low wear resistance and would not scratch the ITO coating on an LCD panel surface.
Additionally, it can be seen from examples 9 and 11 that when the abrasive particles of the abrasive included aluminum hydroxide abrasive particles, a suitable amount (1 to 2 wt. %) of aluminum oxide abrasive particles can further be added into the abrasive particles, and the abrasive articles prepared from such abrasive had an actual wear of greater than 5 μm, indicating that the abrasive articles also had a relatively low wear resistance and would not scratch the ITO coating on an LCD panel surface.
Although the aforementioned detailed description contains many specific details for purposes of illustration, one of ordinary skill in the art will appreciate that many variations, changes, substitutions, and alterations to the details are within the scope of the disclosure as claimed. Accordingly, the disclosure described in the detailed description is set forth without imposing any limitations on the claimed disclosure. The proper scope of the disclosure should be determined by the claims and their appropriate legal equivalents. All of the references cited are herein incorporated by reference in their entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201310705725.6 | Dec 2013 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2014/070487 | 12/16/2014 | WO | 00 |
