Patent Application
20190382161
The invention related generally to containers for high-purity materials. More specifically, the invention relates to active containers for high-purity materials and to methods of making such active containers. The invention finds particular applicability in the packaging and storage of materials used in the manufacture of electronic devices (electronic materials) and, in particular, the semiconductor manufacturing industry, as well as in the water, food and pharmaceuticals industries.
In the semiconductor manufacturing industry, process chemicals comprising liquids are used throughout the manufacturing process, for example, in lithography, coating, cleaning, stripping, etching and chemical mechanical planarization (CMP) processes. Such chemicals include, for example, acids, solvents, photoresists, antireflective materials, developers, removers, slurries and cleaning solutions. With continued reductions in critical dimensions required for advanced semiconductor devices, it has become increasingly important that the process chemicals be provided in ultrapure form. However, process chemicals even in purified form typically contain trace amounts of metals such as iron, sodium, nickel, copper, calcium, magnesium and potassium, among others. The presence of metals in the process chemicals can be detrimental, resulting, for example, in patterning defects and alteration of electrical properties of the formed devices, thereby impacting device reliability and product yield. The source of such metal impurities can be from raw materials used in the chemical manufacturing process, or may otherwise be introduced during the manufacturing and packaging processes.
The reduction of metals and other impurities from process chemicals, raw materials and precursors has conventionally been achieved through the use of ion-exchange and/or filtration processes. Following such purification, the chemicals are typically packaged in containers, for example, bottles or other vessels, which are then shipped to and stored by the end user. In the semiconductor manufacturing industry, the chemical containers are often plumbed directly to the process tools used for wafer processing to reduce the likelihood of contamination of the chemicals. It has been found, however, that the chemical containers themselves can be a source for impurities which may be generated in-situ during storage and transportation. Movement of the container such as during transport is believed to exacerbate this problem. In an effort to reduce particle generation in process chemicals, the use of bottles containing a fluorinated liner has been proposed, for example, in U.S. Patent Application Pub. No. 2013/0193164 A1. Avoidance of fluorine-containing materials, however, would be desired for environmental reasons. Moreover, such liners are passive materials and, at best, would not contribute to the total metals in the formulation. It would be desirable to provide a container which, beyond not contributing to total metals in the container material, actively removes such impurities from the contained chemicals. In addition to the electronics industry, such a container would be desirable for use, for example, in the water, food and pharmaceutical industries.
Accordingly, there is a need in the art for improved containers and their methods of making and use, which address one or more problems associated with the state of the art.
In accordance with a first aspect of the invention, provided are containers. The containers comprise: an enclosure member; and optionally an article at least partially within the enclosure member. The enclosure member and/or the article comprise an activated polymeric surface, wherein the activated polymeric surface is formed by a method comprising treatment of a sulfonated polymeric surface with a composition comprising a protic acid.
In accordance with a further aspect of the invention, methods of forming containers having an activated polymeric surface are provided. The methods comprise providing an enclosure member or an enclosure member liner comprising a sulfonated polymeric surface, and treating the sulfonated polymeric surface with a composition comprising a protic acid. The containers and their methods of formation find particular use in the storage of chemicals useful in the electronics industry in the manufacture of electronic devices (i.e., electronic materials), particularly in the semiconductor manufacturing industry, as well as in the water, pharmaceutical and food industries. Electronic materials and other materials which can be stored in the containers of the present invention are typically high-purity materials, and preferably are ultrapure materials.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular forms “a”, “an” and “the” are intended to include singular and plural forms, unless the context indicates otherwise.
The present invention will be described with reference to the following drawing, in which like reference numerals denote like features, and in which:
The containers of the invention comprise an activated polymeric surface effective for removing metal impurities from chemical compositions contained within the containers. Suitable containers include, for example, those used in the storage of high purity chemicals useful in the electronics industry. Such chemicals include, for example, acids, solvents, polymers, photoresists, antireflective materials, developers, removers, slurries and cleaning solutions. The containers find further use, for example, in the water, pharmaceutical and food industries. The containers can take various forms, for example, bottles, cans, boxes, drums and tanks.
Methods of the invention for activating a polymeric surface of a container will now be described. The component comprising the polymeric surface can take various forms with the understanding that at least a portion of the activated surface will be in contact with a chemical composition stored in the container. The polymeric surface to be activated can, for example, include an interior wall of an enclosure member, an enclosure member liner, or an insert that is to be disposed at least partially within the enclosure member.
Suitable materials for the surface to be activated include organic polymers which are capable of being sulfonated. Such polymers have hydrogen atoms bonded to carbon groups which can be replaced by sulfonic acid groups having the sulfur bonded directly to the carbon atoms. The polymer materials are preferably thermoplastic, non-aromatic, hydrocarbon polymers which have a linear carbon-to-carbon backbone molecular structure with only non-aromatic substituents and have a plurality of free hydrogen atoms attached to the carbon atoms of the polymer chain. These polymers are extruded or molded to form the enclosure members, liners or inserts. Examples of these thermoplastic extrusion grade or moldable grade non-aromatic hydrocarbon polymers are homopolymers of ethylene, propylene, isobutylene, methyl-pentene-1, butene-1, vinyl chloride, vinylidene chloride, acrylonitriles, interpolymers of the foregoing monomers with each other, chlorinated polyethylene and chlorinated polypropylene, and blends of the foregoing monomers and copolymers. Of particular interest are the high and low density polyethylene, polypropylene, ethylene/propylene copolymers, ethylene/butene-1 copolymers and blends thereof.
The polymer composition can include one or more optional additives chosen, for example, from antioxidants, pigments, dyes, or extenders known in the art. Such optional additives if used are typically present in the composition in minor amounts such as from 0.01 to 10 wt % based on total solids of the polymer composition.
The polymeric surface is activated through a multi-step process comprising sulfonation and treatment of the sulfonated polymeric surface with a composition comprising a protic acid. Activation of the polymeric surface allows for removal of metal impurities from chemical compositions disposed within the containers which contact the activated surface. Without wishing to be bound by any particular theory, it is believed that metal impurities are removed from the chemical compositions by ion exchange and/or adsorption with the activated polymeric surface. The process chemicals described herein used to treat the polymeric surface, for example, the sulfonation materials, protic acid-containing composition and other materials which may be used in the process such as rinsing agents, are preferably less than 100 ppb per metal, more preferably less than 50 ppb per metal and most preferably less than 10 ppb per metal.
Sulfonation of the polymeric surface can be carried out by techniques well-known in the art. It is to be understood that the desired range of sulfonation to be used will be somewhat dependent upon the material which is to be stored in the container and the particular polymer being sulfonated. A degree of sulfonation that is too low will result in inefficient removal of metal impurities from the material to be disposed within the container, while an excessive degree of sulfonation can result in significant loss in tensile strength of the member being sulfonated, which may cause decomposition of the polymer. Typically, the degree of sulfonation is from 0.5 to 25 atomic %, preferably from 1 to 15 atomic %, and more preferably from 3 to 10 atomic %, based on total carbon atoms on the sulfonated polymer surface. Suitable sulfonation temperatures will depend on the particular technique used, but for any method should be less than the melting point of the treated substrate and polymeric material. The pressure at which the sulfonation is carried out similarly will depend on the particular sulfonation method, and is typically atmospheric, but may be sub-atmospheric (e.g., 10 to 750 Torr) or super-atmospheric (e.g., 770 to 4000 Torr). The sulfonation reaction time can vary significantly depending on method and other variables, with a time of from two minutes to 24 hours being typical.
A typical method of sulfonating a substrate's polymeric surface to be activated is to expose such surface to gaseous sulfur trioxide, preferably diluted with a dry inert gas such as air, argon, nitrogen, helium, carbon dioxide, sulfur dioxide and the like. The concentration of sulfur trioxide in the gaseous sulfonating agent can vary from 0.1 to 50 vol % based on total gaseous sulfonating agent, preferably from 5 to 35 vol % of sulfur trioxide. The sulfur trioxide can be generated in-situ by reacting sulfur dioxide and air over a catalyst bed, such as vanadium oxide (V2O5) or other catalyst beds known in the literature. The time of sulfonation required to produce an acceptable degree of sulfonation varies with the concentration of sulfur trioxide and temperature. For example, degree of sulfonation increases with a higher concentration of sulfur trioxide and higher temperature. It may be desirable to exclude water vapor from the above gases by a conventional drier tube since, in the presence of water in a liquid or vapor form, the sulfur trioxide is converted to droplets of sulfuric acid of varying concentration, and sulfonation of the plastic can be inhibited or prevented. For removal of water, it may further be desirable to purge the sulfonation chamber with a dry inert gas such as air, argon, nitrogen, helium, carbon dioxide, sulfur dioxide, or the like, prior to introduction of the sulfonation reactants. The rate of addition of the gas(es) should be controlled in order to maximize the rate of sulfonation while minimizing any potential adverse effects, such as melting of the polymer. The gas(es) may be added to the sulfonation chamber containing the substrate continuously or in a non-continuous manner, for example, in distinct pulses. The reaction chamber may be at ambient pressure or a pressure less than or greater than ambient pressure. The reaction temperature for the gas phase sulfonation reaction is typically from 20 to 132° C.
A further suitable method for sulfonating a polymeric surface involves contacting the surface with a solution of SO3 in an inert liquid solvent, such as a liquid polychlorinated aliphatic hydrocarbon, for example, methylene chloride, carbon tetrachloride, perchloroethylene, 1,1,2,2-tetrachloroethane, or ethylene dichloride. Suitable concentrations include, for example, from 1 to 25 wt % SO3 based on the total solution. The reaction temperature is typically from 0 to 140° C., with the understanding that the temperature is to be less than the melting point of the polymer being treated.
A further suitable sulfonation method involves contacting the polymeric surface with a chlorosulfonic acid sulfonating agent. The polymeric surface can be sulfonated, for example, with neat chlorosulfonic acid. Optionally, chlorosulfonic acid can be used with one or more additional solvent, for example, a liquid polychlorinated aliphatic hydrocarbon such as methylene chloride, carbon tetrachloride, perchloroethylene, 1,1,2,2-tetrachloroethane, or ethylene dichloride. A typical temperature for this sulfonation method is from 25 to 75° C.
A further suitable sulfonation method involves contacting the polymeric surface with sulfuric acid. Suitable concentrations are not particularly limited. The sulfuric acid can be, for example, in concentrated or non-concentrated form. Suitable concentrations including, for example, 10 wt % or greater, 20 wt % or greater, 30 wt % or greater, 90 wt % or greater, 96 wt % or greater, or 98 wt % or greater sulfuric acid. The concentration of the sulfuric acid can alternatively be 96 wt % or less. The reaction temperature for sulfonation with sulfuric acid is typically from 0 to 140° C., for example, from 30 to 120° C.
A further suitable sulfonation method involves contacting the polymeric surface with fuming sulfuric acid. As used herein, fuming sulfuric acid (also referred to as “oleum”) differs from concentrated sulfuric acid, in that fuming sulfuric acid is 100% sulfuric acid that contains dissolved SO3. The use of fuming sulfuric acid can be advantageous as compared with concentrated sulfuric acid as it is significantly more reactive and the sulfonation reaction therefore occurs more quickly. Typically, the concentration of the fuming sulfuric acid is described as the wt % free SO3 in solution. Typical fuming sulfuric acids are 0.1 to 30 wt % SO3 in solution. The reaction temperature for oleum sulfonation is typically from 0 to 140° C., for example, from 30 to 120° C.
For the sulfonation methods described herein, it is generally known in the art that variables for the sulfonation process include, for example, temperature, reactant concentration, pressure, sulfonation time and properties of the polymer such as percent crystallinity, content of double bonds and porosity. Determination of suitable conditions for the sulfonation methods described above to achieve a desired degree of sulfonation is within the level of one skilled in the art.
Typically, the sulfonated polymeric surface will be rinsed with a rinsing agent, typically a water-miscible liquid, for example, water, preferably deionized (DI) water, methanol, ethanol, acetone or tetrahydrofuran, to remove residual sulfuric acid, reaction by-products and other contaminants. The rinsing agent can be a water-immiscible liquid, for example, toluene, dichloromethane or an ether such as methyl tert-butyl ether, diethyl ether, diamyl ether or other C2-C10 dialkylether. Such rinsing is useful to remove residual unbound acid. Rinsing is typically conducted for a period of time to reach neutrality, i.e., until the spent rinsing material exhibits the same pH level as rinsing material that has not contacted the sulfonated polymeric surface. The rinsing process is typically conducted by filling the article being rinsed, for example, in the case of an enclosure member or liner, emptying the contents and repeating until reaching neutrality. The protic acid solution can in another aspect be applied by immersing the article in a tank containing the protic acid solution and allowing the article to soak, preferably with agitation. The protic acid solution can be applied to the tank in a continuous manner or, more typically, is applied in a batch manner such as by serially filling and draining the tank until reaching neutrality.
The sulfonation process typically results in discoloration of the polymeric surface being treated, wherein a black or dark brown layer is produced. Without wishing to be bound by any particular theory, it is believed that the reaction is one of simultaneous oxidation and sulfonation. The discoloration thus appears to be the result of a complex oxidation of the polymer so that it contains various chromophoric unsaturated polymeric groups and oxidized groups such as hydroxy, keto or carboxylic acid groups. It is further believed that these groups condense with one another to form additional chromophoric groups responsible for the dark color above noted.
It is typically desired to remove or reduce the discoloration layer as it may leach into and contaminate a material to be stored in the container. For this purpose, the discolored surface can optionally be rinsed with a bleaching agent. Suitable bleaching agents include, for example, aqueous solutions of sodium hypochlorite, calcium hypochlorite, hydrogen peroxide, ammonium percarbonate, potassium persulfate, potassium permanganate and sodium di-chromate. Bleaching of the polymeric surface is typically followed by rinsing with a water-miscible liquid such as described above to remove residual bleaching agent, reaction by-products and other contaminants.
The sulfonated polymeric surface is next treated with a composition comprising a protic acid. By treatment with a protic acid, contaminants and metals resulting from the sulfonation process can be removed. Suitable protic acids include, for example, nitric acid, hydrochloric acid, sulfuric acid, acetic acid, citric acid, tartaric acid, iminodiacetic acid, phosphoric acid, boric acid, or a combination thereof. Preferably, the polymeric surface is contacted with a liquid solution of the protic acid. The concentration of the protic acid solution is typically from 1 to 80 wt % acid, and preferably from 10-30 wt % acid. The protic acid solution can be applied to the article, for example, by filling the substrate such as for treatment of an interior polymeric surface of an enclosure member or liner and allowing contact between the protic acid and polymeric surface for a desired period of time, preferably with agitation. The protic acid solution can alternatively be applied by immersing the article in a tank containing the protic acid solution and allowing the article to soak, preferably with agitation. Rinse times of from one hour to 14 days, preferably from 5 to 10 days, are typical. The temperature of the acid rinse is typically from 0 to 100° C., preferably from 20 to 50° C.
The protic-acid treatment can alternatively be conducted in a closed chamber using a protic acid in gas or vapor phase. Suitable protic acids in gas form include, for example, hydrogen chloride and hydrogen fluoride. Suitable protic acids for use in vapor form include those described above with respect to the protic acid solutions. Vapor generation can be accomplished using methods known in the art, for example, bubbling an insert carrier gas, such as air, argon, nitrogen, or helium, into the protic acid solution, and optionally heating the acid. Treatment times of from one hour to 14 days, preferably from 5 to 10 days, are typical. Typically, these treatments can be conducted at atmospheric pressure or super atmospheric pressure. Prior to protic acid treatment of the sulfonated article in this method, the polymeric surface should be treated with an aqueous rinsing agent, typically deionized water, to allow for solubilization and removal of metal contaminants from the polymeric surface during contact with the protic acid. The rinsing treatment can be conducted prior to introduction into the closed chamber such as by filling the article with, or immersing the article in, the rinsing agent. The rinsing time is not critical and the treatment should be sufficient to create a film of water on the polymeric surface to be treated with the protic acid.
If bleaching of the polymeric surface is desired, it can be conducted simultaneously with the protic acid treatment in place of or in addition to a separate bleaching process as described above. For bleaching during protic acid treatment, certain protic acids themselves, for example, nitric acid, can function as a bleaching agent. Optionally, a bleaching agent that is different from the protic acid can be used in combination with the protic acid to treat the polymeric surface. Suitable protic acid/bleaching agent combinations include, for example, any combination of the above-mentioned protic acids and bleaching agents. Particularly suitable combinations include, for example, hydrogen peroxide/sulfuric acid, hydrogen peroxide/hydrochloric acid, hydrogen peroxide/nitric acid and sodium dichromate/sulfuric acid.
The protic acid-treated polymeric surface is typically rinsed with an aqueous-miscible rinsing agent as described above with reference to the post-sulfonic acid treatment rinse. Rinsing is typically conducted for a period of time to reach neutrality.
Optionally, the protic acid-treated polymeric surface can be treated with an agent which neutralizes the sulfonic acid groups on the polymer. This may be desired, for example, to prevent reaction where the material to be stored in the container is not compatible with acid groups. In this case, neutralization of the acid groups can compatibilize the container with the material to be stored. The neutralization agent can be, for example, in liquid or vapor phase. Suitable liquid phase neutralization agents include, for example: primary, secondary or tertiary amines; ammonium hydroxide including quaternary ammonium hydroxide solutions such as tetramethyl ammonium hydroxide; primary, secondary, or tertiary imines; or mixtures thereof. Suitable amines which can be used include primary, secondary or tertiary saturated aliphatic amines of 2-5 carbon atoms which are water soluble and are normally liquids at room temperature, for example, amylamine, dipropylamine, triethylamine, diethylamine, ethylamine, diethylmethylamine, ethanolamine, diethanolamine, triethanolamine and thioethanolamine. Suitable imines which can be used include primary, secondary or tertiary aromatic and aliphatic imines which are water soluble and are normally liquids at room temperature, for example, pyridine, pyrimidine and pyrazine.
The sulfonated plastic surfaces can be dipped into the aqueous solutions or suspensions or can be sprayed with the solutions, washed with water and dried. Typically, the neutralizing agent is added to water in an amount such that the resulting solution contains from 1-20 wt % of the neutralizing agent. The contact time is not critical and a mere dipping or spraying can be sufficient. The temperature at which neutralization is carried out is not critical, and is typically from −20 to 60° C., preferably from 20 to 40° C.
Suitable vapor phase neutralization agents include, for example, gaseous ammonia, methylamine, dimethylamine, trimethylamine and pyridine. For those materials in liquid form at standard conditions, for example, pyridine, the material can be heated to a temperature allowing for vaporization. The contact time between the vapor phase neutralization agent and sulfonated polymeric surface is typically from 1 minute to 24 hours, and more typically from 15 minutes to four hours. The temperature at which vapor phase neutralization is carried out is typically from 0 to 100° C., preferably from 20 to 80° C. In the event of an optional neutralization treatment, the polymeric surface is typically then rinsed with an aqueous-miscible rinsing agent such as described above with reference to the post-sulfonic acid treatment rinse.
Exemplary containers in accordance with the invention will now be described with reference to the drawings.
To increase interaction between the activated polymeric surface and a chemical composition to be stored in the container, it may be desired to provide an activated polymeric surface with increased surface area for greater contact with the chemical composition. It is believed that such increased activated polymeric surface area can provide further reductions in metal contaminants. Increased surface area can be achieved, for example, through surface texturing of the polymeric surface. Suitable textures include raised or indented structures of various geometries, for example, dimples, domes, ridges, grooves, pyramids, rectangular cuboids, cylinders, and combinations thereof. Surface texturing can be accomplished during manufacture of the bottle (or other enclosure member or article).
In the above-described exemplary containers, the enclosure member or liner includes an active interior polymeric surface. Additionally or alternatively, the container can include an insert disposed at least partially within the enclosure member that includes an activated polymeric surface for metals removal. For purposes of increasing the activated surface area of an insert, it may be desired to include surface texturing such as described with respect to
The following non-limiting examples are illustrative of the invention.
15 ml LDPE white translucent bottles (2.4 cm diameter, 5.8 cm height) were subjected to gas-phase sulfonation. The pre-sulfonated bottles exhibited no measurable elemental sulfur, and the sulfonated bottles exhibited an elemental sulfur content at the surface of 6.9 atomic percent as determined by x-ray photoelectron spectroscopy (XPS). The sulfonated bottles were visually observed to have become discolored black inside and out. The bottles were rinsed with deionized (DI) water (18 Megaohm). A sulfonated bottle was filled with 20 wt % Optima™ nitric acid (Fisher Scientific) and the bottle was shaken for seven days. The nitric acid turned yellow in color and the discoloration on the inner walls of the bottle was substantially removed, indicating removal of sulfonation by-products. The bottle was then rinsed with DI water (18 Megaohm), and the sulfur content at the surface as measured by XPS was 3.4 atomic percent. 10 ml OC™3050 Immersion Topcoat Material (Dow Electronic Materials, Marlborough, Mass.), which includes a mixture of acrylic resins and organic solvents, was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. ICP metals analysis included analysis of two samples from bottle for all examples. The results are shown in Table 1.
A 15 ml LDPE white translucent bottle (2.4 cm diameter, 5.8 cm height) was filled with 20 wt % Optima™ nitric acid (Fisher Scientific) and the bottle was shaken for seven days. The bottle was then rinsed with DI water (18 Megaohm). 10 ml OC™3050 Immersion Topcoat Material (Dow Electronic Materials) was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A sulfonated/DI water-rinsed bottle was prepared as described in Example 1. 10 ml OC™3050 Immersion Topcoat Material (Dow Electronic Materials) was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A nitric acid-treated/DI water-rinsed sulfonated bottle was prepared as described in Example 1. 10 ml TraceSELECT Ultra TMAH solution (25 wt % in water) (Fluka) was added to the bottle and shaken for one week. The TMAH solution gained a dark brown color and was removed from the bottle. The bottle was rinsed with 18 MOhm DI water, and 10 ml of OC™3050 Immersion Topcoat Material (Dow Electronic Materials) was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A nitric acid-treated/DI water-rinsed sulfonated bottle was prepared as described in Example 1. 10 ml Optima ammonium hydroxide solution (20 wt %) (Fisher Scientific) was added to the bottle and shaken for one week. The TMAH solution gained a dark brown color and was removed from the bottle. The bottle was rinsed with 18 MOhm DI water, and 10 ml of 0C™3050 Immersion Topcoat Material (Dow Electronic Materials) was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
To study suitability for reuse of containers of the invention, a bottle prepared as in Example 1, which was sulfonated, nitric acid-washed and contained OC™3050 Immersion Topcoat Material (Dow Electronic Materials), was rinsed with distilled ethyl lactate. The bottle was then rinsed with 18 MOhm DI water and treated with 20 wt % Optima nitric acid (Fisher Scientific) for seven days. The resulting nitric acid remained clear. The bottle was rinsed with 18 MOhm DI water, and 10 ml of OC™3050 Immersion Topcoat Material (Dow Electronic Materials) was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A sulfonated/DI water-rinsed bottle was prepared as described in Example 1. The bottle was filled with 98 wt % Optima sulfuric acid (Fisher Scientific) for seven days. The resulting sulfuric acid remained clear, and the inside of the bottle walls remained black. The bottle was rinsed with 18 MOhm DI water, and 10 ml of OC™3050 Immersion Topcoat Material (Dow Electronic Materials) was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A sulfonated/DI water-rinsed bottle was prepared as described in Example 1. The bottle was filled with a 1:4 mixture (by volume) of 30 wt % Optima hydrogen peroxide (Fisher Scientific): 98 wt % Optima sulfuric acid (Fisher Scientific), and the bottle was shaken for seven days. The resulting sulfuric acid remained clear, and the color of the interior bottle walls lightened from black to brown. The bottle was rinsed with 18 MOhm DI water, and 10 ml of OC™3050 Immersion Topcoat Material (Dow Electronic Materials) was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A sulfonated/DI water-rinsed bottle was prepared as described in Example 1. The bottle was filled with TraceSelect acetic acid (Fluka), and the bottle was shaken for seven days. The resulting acetic acid remained clear, and the inside of the bottle walls turned slightly brownish. The bottle was rinsed with 18 MOhm DI water, and 10 ml of OC™3050 Immersion Topcoat Material (Dow Electronic Materials) was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A 15 ml LDPE white translucent bottle (2.4 cm diameter, 5.8 cm height) was filled with 20 wt % Optima™ nitric acid (Fisher Scientific) and the bottle was shaken for seven days. The bottle was then rinsed with DI water (18 Megaohm). 10 ml isoamyl ether (Toyo Gosei) was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A nitric acid-treated/DI water-rinsed sulfonated bottle was prepared as described in Example 1. 10 ml isoamyl ether (Toyo Gosei) was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A 15 ml LDPE white translucent bottle (2.4 cm diameter, 5.8 cm height) was filled with 20 wt % Optima™ nitric acid (Fisher Scientific) and the bottle was shaken for seven days. The bottle was then rinsed with DI water (18 Megaohm). 10 ml ethyl lactate was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A nitric acid-treated/DI water-rinsed sulfonated bottle was prepared as described in Example 1. 10 ml ethyl lactate was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A 15 ml LDPE white translucent bottle (2.4 cm diameter, 5.8 cm height) was filled with 20 wt % Optima™ nitric acid (Fisher Scientific) and the bottle was shaken for seven days. The bottle was then rinsed with DI water (18 Megaohm). 10 ml hydroxybutyric acid methyl ester (HBM) was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A nitric acid-treated/DI water-rinsed sulfonated bottle was prepared as described in Example 1. 10 ml HBM was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A 15 ml LDPE white translucent bottle (2.4 cm diameter, 5.8 cm height) was filled with 20 wt % Optima™ nitric acid (Fisher Scientific) and the bottle was shaken for seven days. The bottle was then rinsed with DI water (18 Megaohm). 10 ml Propylene glycol monomethyl ether acetate (PGMEA) was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
A nitric acid-treated/DI water-rinsed sulfonated bottle was prepared as described in Example 1. 10 ml PGMEA was added to the bottle. The bottle was shaken for seven days and metals analysis was conducted with an Agilent 8800 ICP-MS system. The results are shown in Table 1.
| Number | Date | Country | |
|---|---|---|---|
| 62686078 | Jun 2018 | US |
