Coated container and method for forming such container

Abstract

The present invention provides coated containers and methods for forming such containers. [Solution] A container comprising an enclosure having an outer surface and an inner surface, and an optionally derivatizable polydopamine coating disposed on the inner surface of the enclosure is disclosed herein. A method for coating a solution is also disclosed herein, comprising the steps of (a) providing a container comprising an enclosure having an outer surface and an inner surface, and (b) placing a solution comprising dopamine hydrochloride, a buffer, and a solvent inside the container.

Description

Technical Field

[0001] The present disclosure generally relates to containers for high purity materials. More specifically, the present disclosure relates to coating containers for storing high purity materials and methods of manufacturing such coated containers. The present disclosure has particular applicability in the manufacture of electronic devices (electronic materials) and, in particular, in the semiconductor manufacturing industry, as well as in the packaging and storage of materials used in the water, food and pharmaceutical industries.

Background Art

[0002] In the semiconductor manufacturing industry, process chemicals containing liquids are used throughout the manufacturing process, for example, in lithography, coating, cleaning, stripping, etching and chemical mechanical polishing (CMP) processes. Such chemicals include, for example, acids, solvents, photoresists, anti-reflective materials, developers, removers, slurries and cleaning solutions. Due to the continuous reduction of critical dimensions required for advanced semiconductor devices, it is becoming increasingly important for process chemicals to be provided in ultra-high purity form. However, even in purified form, process chemicals typically contain trace amounts of metals such as, inter alia, iron, sodium, nickel, copper, calcium, magnesium and potassium. The presence of metals in process chemicals can be detrimental and can, for example, result in patterning defects and changes in electrical properties of the devices formed, thereby affecting the reliability and product yield of the devices. Such sources of metal impurities can be derived from raw materials used in the chemical manufacturing process or otherwise introduced during the manufacturing and packaging processes.

[0003] The reduction of metals and other impurities from process chemicals, raw materials, and precursors is conventionally achieved by the use of ion exchange and / or filtration processes. After such purification, chemicals are typically packaged in containers, such as bottles or other vessels, and then shipped to end users for storage. In the semiconductor manufacturing industry, chemical containers are often directly connected to process tools used in wafer processing to reduce the possibility of chemical contamination. However, it has been found that the chemical containers themselves can be sources of impurities that may be generated in situ during storage and transport. Movement of the containers, such as during transport, is thought to exacerbate this problem. To reduce the generation of particles in process chemicals, the use of bottles containing fluorinated liners has been proposed, for example, in (Patent Document 1). However, it is desirable to avoid fluorine-containing materials for environmental reasons. Furthermore, such liners are passivation materials and, at best, do not contribute to the total metal content in the formulation. In addition to not contributing to the total metal content in the container material, it is desirable to provide a container that actively removes such impurities from the contained chemicals. In addition to the electronics industry, such containers are also desirable for use in industries such as water, food, and pharmaceuticals. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] U.S. Patent Application Publication No. 2013 / 0193164A1 [Overview of the project] [Problems that the invention aims to solve]

[0005] Therefore, there is a need in this field for improved containers, as well as methods for their manufacture and use, that address one or more problems related to the latest technologies. [Means for solving the problem]

[0006] This specification discloses a container comprising an enclosure having an outer surface and an inner surface, and a container comprising an optionally derivatizable polydopamine coating disposed on the inner surface of the enclosure.

[0007] A method for coating a container is also disclosed herein, comprising the steps of (a) providing a container including an enclosure having an outer surface and an inner surface, and (b) placing a solution containing dopamine hydrochloride, a buffer, and a solvent inside the container. [Brief explanation of the drawing]

[0008] [Figure 1] The drawing shows a typical embodiment of a container having a polydopamine coating on its inner surface. [Modes for carrying out the invention]

[0009] The technical terms used herein are for the purpose of describing specific embodiments and are not intended to limit the invention. The singular forms “a,” “an,” and “the” are intended to include both singular and plural forms unless otherwise indicated in the context.

[0010] Autopolymerization refers to the process by which monomers form large chain molecules (i.e., polymers) without the need for chemical initiators. In this case, oxygen dissolved in the solvent is thought to play a similar role to an initiator in the polymerization process. This process can be accelerated by adding chemical oxidizers, which can result in improved coatings.

[0011] Containers having a polydopamine coating or a polydopamine derivative coating on their inner surface are disclosed herein. Polydopamine or its derivatives form a stable coating on the inner surface of the container. They can exhibit metal removal properties from contents stored in the container. These contents can include, for example, acids, solvents, polymers, photoresists, anti-reflective materials, developers, removers, slurries, and cleaning solutions. Furthermore, polydopamine can prevent metal leaching from the container by passivating the surface. Polydopamine can be coated on a wide variety of surfaces, such as glass, metals, and inorganic or organic polymers, using simple solution-based methods.

[0012] A method for coating the inner surface of a container with a layer of polydopamine is also disclosed herein, comprising the optional step of derivatizing the polydopamine layer. This method involves dissolving a dopamine-containing monomer and a buffer in a solvent to form a reactive solution, which is then added to the container to be coated. The buffer promotes the polymerization of the dopamine-containing monomer to form polydopamine. The reaction to form polydopamine can be carried out in the container itself or in a reactor (separate from the container) and then poured into the container. The reactants (dopamine-containing monomer and buffer) are preferably added directly to the container along with the solvent, where they undergo a reaction to form a polydopamine coating. It is preferable to gently agitate the container with the reactants inside during coating formation to help achieve a homogeneous reaction and to help achieve a coating on the inner surface of the container. The coated container is then typically washed with water to remove any rough polydopamine residue or contaminants remaining from the coating process.

[0013] The container comprises an enclosure and, optionally, an article at least partially within the enclosure. The drawings show a typical embodiment of container 1 in which a polydopamine coating is applied to the inner surface of the container. Container 1 includes an enclosure 2 that defines the outer perimeter of the container. Enclosure 2 has an outer surface 2A and an inner surface 2B. Container 1 typically has a cap 4 for sealing enclosure 2 from ambient air. In short, container 1 can be exposed to ambient air or can be airtightly sealed therefrom by the cap 4 (also called a lid). The cap 4 typically prevents degradation of the contents of the container by evaporation and leakage. The inner surface 2B of enclosure 2 is coated with a polydopamine coating 3. A chemical composition 5 can be stored in container 1, and during storage time, metallic impurities can be removed therefrom by the polydopamine coating.

[0014] Containers with a coating applied to them are effective in removing metallic impurities from the chemical compositions held within the container. Suitable containers include, for example, those used in the storage of high-purity chemicals (electronic materials) useful in the electronics industry. Such chemicals include, for example, acids, solvents, polymers, photoresists, anti-reflective materials, developers, removers, slurries, and cleaning solutions. Containers also have further applications in the water, pharmaceutical, and food industries. Containers can take various forms, such as bottles, cans, boxes, drums, and tanks. Suitable containers include those used for transporting materials, such as tank car containers.

[0015] In embodiments, the container holds a chemical composition in contact with the polydopamine coating. Preferably, the chemical composition is an electronic material. The chemical composition typically contains an organic solvent. Also preferably, the chemical composition is a high-purity or ultra-high-purity chemical composition. The term "high-purity" means each individual metal contaminant at 1 ppb or less. The term "ultra-high-purity" means each individual metal contaminant at 100 ppt or less. Preferably, the chemical composition contains a total amount of metal contaminants of less than 10 ppb, less than 5 ppb, less than 1 ppt, less than 0.5 ppt, or less than 0.1 ppt.

[0016] The container may be made of metal, glass, polymer, or a combination thereof. Suitable metals include copper, tin, steel, brass, aluminum, etc., or combinations thereof. Suitable glasses include silica, alumina, titania, zirconia, quartz, etc., or combinations thereof.

[0017] The polymer material is preferably a thermoplastic non-aromatic hydrocarbon polymer having a linear carbon-carbon main chain molecular structure with only non-aromatic substituents and multiple free hydrogen atoms bonded to carbon atoms in the polymer chain. These polymers can be blow-molded or molded to form containers. Examples of these thermoplastic extruded or moldable hydrocarbon polymers include homopolymers of ethylene, propylene, isobutylene, methyl-pentene-1, butene-1, vinyl chloride, vinylidene chloride, and acrylonitrile; copolymers of the aforementioned monomers; chlorinated polyethylene and chlorinated polypropylene; as well as fluoropolymers such as polytetrafluoroethylene and perfluoroalkoxy polymers; polycarbonates, polyesters, polystyrene, and blends of the aforementioned monomers and copolymers. High-density and low-density polyethylene, polypropylene, ethylene / propylene copolymers, ethylene / 1-butene copolymers, and blends thereof are particularly important.

[0018] The polymer composition used to manufacture the container can include one or more optional additives selected, for example, from antioxidants, pigments, dyes, or extenders known in the art. When used, such optional additives are typically present in the composition in small amounts, such as 0.01 to 10% by weight, based on the total solids of the polymer composition.

[0019] As described above, the dopamine-containing monomer is polymerized in solution using a buffer. The dopamine-containing monomer, buffer, solvent, and any additional components are added to a container (to be coated) or a reactor (not a container to be coated) to form a reactive solution. The dopamine-containing monomer undergoes self-polymerization to form polydopamine.

[0020] The dopamine-containing monomer is typically in the form of a salt. In such cases, dopamine is preferably present in its protonated form with a halide counterion, such as Cl - , Br - , F - or I - counterion. In a preferred embodiment, the dopamine-containing monomer is dopamine hydrochloride. The dopamine-containing monomer is typically present in the reactive solution in an amount of 0.01 to 10 weight percent (wt%) based on the total weight of the reactive solution. The dopamine-containing monomer is preferably present in the reactive solution in an amount of 0.02 to 5 wt%, 0.02 to 1 wt%, or 0.05 to 0.20 wt% based on the total weight of the reactive solution.

[0021] [[ID=2L]]The buffer is first used to adjust the pH of the solution such that it is in a range that promotes the self-polymerization of the dopamine-containing monomer. The buffer preferably has a pKa of 7.0 to 9.0.

[0022] Examples of buffers include Tris buffer (tris(hydroxymethyl)aminomethane), sodium dihydrogen phosphate, potassium dihydrogen phosphate, or combinations thereof.

[0023] The buffer is typically present in the reactive solution in an amount of 0.01 to 5% by weight, based on the total weight of the reactive solution. The buffer is preferably present in the reactive solution in an amount of 0.01 to 3% by weight, 0.05 to 1% by weight, or 0.10 to 0.30% by weight, based on the total weight of the reactive solution.

[0024] The solvent present in the reactive solution should be capable of dissolving the dopamine-containing monomer and all other solid components of the solution. The solvent forms the remainder of the reactive solution. Examples of suitable solvents are water, organic solvents such as alcohols, or combinations thereof. Particularly preferred solvents include ethanol and / or water.

[0025] The solvent is typically present in the reactive solution in an amount of 90 to 99.99% by weight, based on the total weight of the reactive solution. The solvent is preferably present in the reactive solution in an amount of 95 to 99.99% by weight, 98 to 99.90% by weight, or 99.50 to 99.85% by weight, based on the total weight of the reactive solution.

[0026] In a method of placing a coating on the inner surface of the first container, a reactive solution containing a dopamine-containing monomer, a buffer, a solvent, and any additional components is poured into the first container or into a reactor and typically subjected to a first stirring process. When placing the reactants in the first container, the first container is typically sealed with a lid and placed in a first stirrer to facilitate the conversion of the dopamine container monomer to polydopamine. The stirring technique is not particularly limited, but the stirrer is preferably a roller that stirs the contents of the first container thereon. In this case, the first container is rotated on the roller. The polydopamine produced by the self-polymerization of the dopamine-containing monomer coats the inner surface of the first container and the lid that seals the first container. Stirring is typically carried out at a temperature of 10 to 50 °C, preferably 18 to 40 °C, for 2 hours to 96 hours, preferably 5 to 80 hours, and more preferably 10 to 30 hours.

[0027] As autopolymerization progresses, the solution appears to darken, and the inner surface of the first container is coated with polydopamine. This coating of the inner surface of the first container occurs during autopolymerization. Once the coating of the inner surface of the first container is complete, the contents of the first container can be released into the second container, from which some of the components can be recycled if necessary.

[0028] Next, the first container is typically filled with, for example, deionized water and rinsed by subjecting it to a second stirring process at a temperature of 10 to 50°C, preferably at room temperature, for a period of typically 30 minutes to 5 hours, to remove all unreacted reactants (e.g., dopamine-containing monomers and / or buffers) and polydopamine not bonded to the coating. Polydopamine not bonded to the coating may include low molecular weight reaction products. The second stirring process may require sonication. After the second stirring process is complete, the deionized water is removed from the first container.

[0029] Furthermore, it is conceivable that a polydopamine coating could be formed by applying a reactive solution through other techniques, such as spraying it onto the inner surface of a container.

[0030] In another embodiment, the first container can be cleaned by spraying high-pressure water into the interior of the first container to remove unreacted reactants and unjoined polydopamine.

[0031] Next, an organic solvent can be optionally added to the first container and subjected to a third stirring step at a temperature of 10-50°C, preferably room temperature, for 30 minutes to 5 hours, during which all unreacted reactants or low molecular weight products are removed from the first container. The organic solvent is preferably propylene glycol methyl ether acetate (PGMEA). Next, the container can be blow-dried using purified air or nitrogen.

[0032] The polydopamine coating on the inner surface and lid of the container has an average thickness of 1 to 100 nanometers, preferably 5 to 50 nanometers. If a thicker coating is desired, the use of multiple layers of polydopamine coating can also be considered and may be useful.

[0033] In embodiments, polydopamine can be prepared in a large batch reactor or a continuous reactor by reacting the reactants together until the color of the reactant solution begins to change. The color change indicates that autopolymerization has begun. For example, the color may be observed to change from light orange to darker, and finally to black, indicating that polymerization to high molecular weight polydopamine has occurred. Before autopolymerization is complete, the reaction product can be released into several containers, each sealed with a lid, and subjected to a first stirring process on rollers. The autopolymerization process is completed in each container during the first stirring process, resulting in the formation of a polydopamine coating on the inner surface of each of the multiple containers. Stirring can be carried out at a suitable temperature for a certain period of time, which promotes the precipitation of polydopamine from the solution onto the inner surface of the containers.

[0034] After the inner coating is complete, the solution is removed from the containers, and the containers are subjected to one or more additional stirring processes, for example, second and third stirring processes using water and optionally a solvent, respectively, to remove any trace amounts of unreacted reactants and unbonded polydopamine, thus leaving a stable coating on the inner surfaces of each container and their respective lids.

[0035] In embodiments, the polydopamine coating process can be accelerated by adding an oxidizing agent to a coating solution containing dopamine-containing monomers, a pH buffer, and a solvent. The oxidizing agent is thought to promote the polymerization of dopamine, resulting in a greater deposition of polydopamine on the surface of the bottle. The oxidizing agent is preferably water-soluble and includes, for example, hydrogen peroxide, organic peroxides, nitrates, permanganates, periodates, persulfates, dichromates, chlorates, perborates, or combinations thereof. When used, the oxidizing agent is typically present in the solution in an amount of 0.001% to 10% by weight based on the total weight of the solution. More preferably, it is in an amount of 0.01% to 5% or 0.05 to 0.1% by weight based on the total weight of the reactive solution.

[0036] In embodiments, polydopamine can be functionalized after polymerization to form polydopamine derivatives. Derivatized polydopamine can exhibit improved effectiveness in removing metals from the contents of a container. Functionalizing agents that can be used to functionalize polydopamine include, for example, primary amines, secondary amines, tertiary amines, as well as moieties or combinations thereof containing carboxylic acids functionalized with amines and / or thiols. The amines may be, for example, linear or cyclic amines. Preferred amines are primary amines, secondary amines, or combinations thereof.

[0037] Examples of primary amines include methylamine, ethylamine, propylamine, ethylenediamine, monoethanolamine, etc., or combinations thereof. Examples of secondary amines include dialkylamines such as dimethylamine, diethylamine, dipropylamine, dibutylamine, and diethanolamine, or combinations thereof.

[0038] In embodiments, amine-functionalized carboxylic acids can be used as functionalizing agents. The carboxylic acids present in these functionalizing agents enhance the metal removal capability compared to functionalizing agents containing only primary or secondary amines. Examples include aminopolycarboxylic acids (APCAs) such as iminodiacetic acid, aspartic acid, ethylenediaminetetraacetic acid, and hyaluronic acid, or combinations thereof.

[0039] Polydopamine can be derivatized with functionalizing agents containing thiols and carboxylic acids. An example of a functionalizing agent containing both thiols and carboxylic acids is mercaptosuccinic acid. Furthermore, functionalizing agents containing both thiols and amines can be used to facilitate the removal of metals from the contents of a container.

[0040] In embodiments, amine and / or thiol-containing functionalizing agents containing sulfonic acid groups can also be used to facilitate the removal of metals from the contents of the container. Examples of such functionalizing agents include sulfamidic acid, 3-mercapto-1-propanesulfonic acid, or combinations thereof.

[0041] Derivatization of the polydopamine coating is preferably carried out after the formation of the polydopamine coating. The functionalizing agent may be dissolved in a solvent before being added to the container to be coated with polydopamine. In another embodiment, the functionalizing agent may be added to the reactive solution before the polydopamine is formed on the inner surface of the container. The solvent is preferably water, an alcohol, or a combination thereof. A preferred alcohol is ethanol. A preferred solvent is water. The container may be sealed with a lid and typically subjected to rolling at a temperature of 10-50°C for a typical time of 2-48 hours, preferably 6-24 hours. The contents of the container can then be released from the container, and the container can be washed with water, and then separately washed with a solvent as detailed above (e.g., PGMEA). The container can then be dried, for example, using air or nitrogen.

[0042] In one embodiment, the functionalizing agent is present in the solution in an amount of 0.01 to 10% by weight based on the total weight of the reactive solution. In another embodiment, the functionalizing agent is present in the solution in an amount of 0.05 to 0.50% by weight based on the total weight of the reactive solution.

[0043] Derivatized polydopamine coatings can exhibit a greater overall ability to extract ionic impurities from solutions held in a container. In embodiments, derivatized polydopamine coatings can extract at least 5% by weight more, preferably at least 10% by weight more, and more preferably 15% by weight more, ionic impurities than underivatized polydopamine coatings of the same thickness.

[0044] Polydopamine or derivatized polydopamine can form a continuous coating on the inner surface of a container (including the enclosure and optionally the lid). Therefore, the coating can come into continuous contact with the material inside the container, resulting in a reduction in the impurity levels of the stored material.

[0045] This disclosure may include the following embodiments 1 to 11. [Aspect 1] An enclosure having an outer surface and an inner surface, A container comprising an optionally derivatizable polydopamine coating disposed on the inner surface of the enclosure. [Aspect 2] The container according to embodiment 1, wherein the enclosure comprises metal, glass, or polymer. [Aspect 3] The container according to embodiment 1 or 2, wherein the polydopamine coating is derivatized. [Aspect 4] The container according to embodiment 3, wherein the polydopamine coating is derivatized with an amine, thiol, carboxylic acid, or a combination thereof. [Aspect 5] The container according to embodiment 4, wherein the amine is dimethylamine. [Aspect 6] The container according to any one of embodiments 1 to 5, wherein the polydopamine coating has a thickness of 1 to 100 nanometers. [Aspect 7] The container according to any one of embodiments 1 to 6, wherein the container has a chemical composition in contact with the polydopamine coating. [Aspect 8] The container according to embodiment 7, wherein the chemical composition contains an organic solvent. [Aspect 9] A container according to any one of embodiments 1 to 8, further comprising a cap for sealing the enclosure. [Aspect 10] (a) A step of providing a container including an enclosure having an outer surface and an inner surface, (b) A method for coating a container, comprising the step of placing a solution containing dopamine hydrochloride, a buffer, and a solvent inside the container. [Aspect 11] The method according to embodiment 10, wherein the solution further comprises an oxidizing agent. Polydopamine and derivatized polydopamine coatings, as well as methods for producing them, as detailed herein, are illustrated by the following non-limiting examples. [Examples]

[0046] Example 1 This example was performed to demonstrate the preparation of a polydopamine coating on a low-density polyethylene (LDPE) container. 0.15 g of dopamine hydrochloride (Fisher Scientific), 0.06 g of Tris buffer (tris(hydroxymethyl)aminomethane) (Fisher Scientific), and 50 mL of deionized (DI) water were added to a 60 mL LDPE container. The LDPE container was a bottle. The container was stirred on a roller for 3 days, during which time the solution was observed to gradually darken. After 3 days, the solution was discarded, and a polydopamine coating without the usual color was observed inside the container. Fresh DI water was added to the container and sonicated for 2 hours. The water was discarded, propylene glycol methyl ether acetate (PGMEA) was added to the container, and it was sonicated for a further 2 hours.

[0047] Next, PGMEA containing a custom multi-element standard (SCP Science) was placed in two containers: one an uncoated control standard and the other with a polydopamine coating on its inner surface. This produced solutions containing approximately 10 ppb each of the following metals: Al, Ca, Cr, Cu, Fe, Mg, Mn, Ni, K, Na, Sn, Ti, and Zn. Each container was shaken overnight. The following day, the contents of each container were analyzed for metal content using an Agilent 7700 Single Quadrupole inductively coupled plasma-mass spectrometer (ICP-MS). The results in parts per billion (ppb) are shown below. The polydopamine coating appeared to reduce the concentrations of Cu and Zn by more than 90%, while significant reductions in Al, Cr, Mn, Ni, and Sn were also observed, as can be seen in Table 1.

[0048] [Table 1]

[0049] Example 2 This example was performed to verify whether a polydopamine-coated container contained any defects in the coating placed on the inner surface of the container.

[0050] 1.88 g of dopamine hydrochloride (Alfa Aesar) and 4.54 g of Tris buffer (tris(hydroxymethyl)aminomethane) (Fisher Scientific) were added to two glass gallon containers along with 3750 ml of DI water. Equal volumes of the reactants were placed in both containers and sealed with lids. Both containers were placed on rollers overnight (approximately 16 hours) and agitated by rolling. The contents were removed from the containers the following day. The containers were then manually washed five times with DI water to remove any residual polydopamine solution. An uncoated control container was subjected to the same manual washing procedure.

[0051] Next, three containers were cleaned and dried using an automated container washing system designed for producing containers for packaging high-purity chemicals. Filtered PGMEA was then placed in the containers. To test the contents for film defects, the containers were placed in a dispensing wafer track, spin-coated onto unused Si wafers, and then soft-baked at 175°C for 60 seconds. The wafers were then inspected for defects using the KLA Tencor Surfscan SP5 defect inspection tool. The inspection tool uses a laser to scan the wafer for any heterogeneity up to a specific size threshold, and then classifies it as a "defect."

[0052] The results for the total number of defects are shown in Table 2 below, where it can be seen that the polydopamine coating did not increase the total number of defects.

[0053] [Table 2]

[0054] Next, the three containers (Table 2) were tested for metallic impurities using an Agilent 8900 Triple Quadrupole ICP-MS. The results for metals are shown in Table 3 below (all results are in ppb units).

[0055] [Table 3]

[0056] Example 3 This example was conducted to demonstrate the efficiency of derivatized polydopamine coating in removing metallic impurities from solutions in containers. The polydopamine coating was derivatized with dimethylamine. The polydopamine coating and the derivatized polydopamine coating were each placed on the inner surfaces of two separate containers. Both containers (one with the polydopamine coating and the other with the derivatized polydopamine coating) were evaluated for their ability to remove ionic impurities from the contents of the containers.

[0057] Each container was coated as follows: 0.03 g of dopamine hydrochloride (Fisher Scientific), 0.07 g of Tris buffer (tris(hydroxymethyl)aminomethane) (Fisher Scientific), and 60 mL of DI water were added to two 60 mL LDPE containers. The containers were stirred on rollers overnight, then the contents were discarded, the containers were washed with DI water, and blow-dried under nitrogen. Next, 0.76 g of 40 wt% dimethylamine (DMA) aqueous solution (Sigma Aldrich) and 59.37 g of DI water were added to one of the containers. The container was returned to the rollers overnight, then the contents were removed, the containers were washed as described above, and blow-dried.

[0058] Next, 60 g of PGMEA was placed in each container, with approximately 10 ppb added for each metal of the custom-ordered multi-element standard used in Example 1. These were then stirred (shaked) overnight. Uncoated control standards were also evaluated along with the coated containers. The following day, the contents were analyzed for metal content using an Agilent 7700 Single Quadrupole inductively coupled plasma-mass spectrometer (ICP-MS). The results in ppb units are shown in Table 4 below.

[0059] [Table 4]

[0060] Example 4 This example was conducted to demonstrate the efficiency of an oxidizing agent in promoting the removal of ionic impurities from the contents of a polydopamine-coated container. One container had a polydopamine coating containing an oxidizing agent during its formation, while the other container had a polydopamine coating without an oxidizing agent during its formation. Both polydopamine coatings were then derivatized with dimethylamine.

[0061] Each polydopamine coating was formed on the inner surface of the container as follows: 0.06 g of dopamine hydrochloride (Fisher Scientific) and 0.07 g of Tris buffer (tris(hydroxymethyl)aminomethane) (Fisher Scientific) were added to two 60 mL LDPE bottles. 60 mL of DI water was added to one container, and 60 mL of DI water containing 7 mg of dissolved sodium metaperiodate (oxidizing agent, Fisher Scientific) was added to the other container. The containers were stirred on a roller overnight, then the contents were discarded, the containers were washed with DI water, and blow-dried with nitrogen.

[0062] Next, 0.30 g of 40 wt% dimethylamine (DMA) aqueous solution (Sigma Aldrich) and 60 mL of DI water were added to both containers. The containers were returned to the rollers and stirred overnight. After that, the contents were discarded, the containers were washed as described above, and blow-dried.

[0063] Next, 60 g of PGMEA, with approximately 10 ppb added for each metal of the custom-ordered multi-element standard used in Example 1, was placed in a polydopamine-coated container along with one uncoated control container. They were then stirred (shaked) overnight. The following day, the contents were analyzed for metal content using an Agilent 7700 Single Quadrupole inductively coupled plasma-mass spectrometer (ICP-MS). The results in ppb units are shown in Table 5 below.

[0064] [Table 5] [Explanation of symbols]

[0065] 1 container 2 enclosures 2A External surface 2B Inner 3. Polydopamine coating 4 caps 5 Chemical composition

Claims

1. An enclosure having an outer surface and an inner surface, A container comprising a derivatized polydopamine coating disposed on the inner surface of the enclosure.

2. The container according to claim 1, wherein the enclosure comprises metal, glass, or polymer.

3. The container according to claim 1, wherein the polydopamine coating is derivatized with an amine, thiol, carboxylic acid, or a combination thereof.

4. The container according to claim 3, wherein the amine is dimethylamine.

5. The container according to claim 1, wherein the polydopamine coating has a thickness of 1 to 100 nanometers.

6. The container according to claim 1, wherein the container has a chemical composition in contact with the polydopamine coating.

7. The container according to claim 6, wherein the chemical composition contains an organic solvent.

8. The container according to claim 1, further comprising a cap for sealing the enclosure.

9. (a) A step of providing a container including an enclosure having an outer surface and an inner surface, (b) A step of placing a solution containing dopamine hydrochloride, a buffer, and a solvent into the container, (c) A step of forming a polydopamine coating on the inner surface of the container, (d) A method for coating a container, comprising the step of derivatizing the polydopamine coating.

10. The method according to claim 9, wherein the solution further comprises an oxidizing agent.

Images