CN1242039A - Cleaning method for polyethylene terephtalate containers - Google Patents

Abstract

The invention discloses a method for cleaning a polyethylene terephthalate container, which comprises contacting the PET container with an alkaline washing solution with a temperature lower than 60°C. The alkaline lotion is prepared from the first concentrated solution, the second concentrated solution, an alkaline source and balanced water. The first concentrate preferably contains the first nonionic surfactant, the first builder and an effective amount of acid to ensure a phase stable solution. The second concentrate preferably contains a second nonionic surfactant and a second builder. The first concentrate and the second concentrate are present in the wash solution at a concentration in the range of about 0.3% to 2.0% by weight. Preferably the cloud point of the first nonionic surfactant ranges from about 5°C to 60°C.

Description

Cleaning methods for polyethylene terephthalate containers

field of invention

In general, the present invention relates to methods and compositions for cleaning polyethylene terephthalate containers. More particularly, the present invention relates to methods and compositions for removing mold present on polyethylene terephthalate containers while at the same time reducing surface haze.

Background of the invention

Like many industries, the beverage industry has moved in a more economical direction, resulting in some real changes in the way beverages are bottled and distributed. In the past decade, the beverage industry has shifted from glass containers to plastic containers. Plastic containers can be made of a variety of materials according to different uses. One material is polyethylene terephthalate, "PET". The two types of PET bottles commonly used are single-use bottles and recycle bottles. Single-use bottles are bottles that are filled, used and then discarded. Multi-cycle bottles can be recycled and used again, but must be washed before refilling.

PET bottles are superior to glass bottles in several ways. Their light weight reduces shipping costs. They won't shatter like glass bottles and generally don't break when hit on a hard surface. Conveyor wear due to containers in the packaging plant is also reduced. After the bottle is opened, the cap can generally be re-sealed.

The disadvantage is that PET bottles are easily scratched and are susceptible to chemical corrosion during washing. PET containers also cannot withstand conditions above 60°C. Exposing it to temperatures above 60°C will deform and/or shrink the bottle.

In the United States, the recycling of PET bottles has been approved by the Food and Drug Administration, allowing used bottles to be refurbished. At 50 to 75 cents a pound for new resin, recycling used bottles makes economics attractive. In the future, it is expected that its glass soft drink bottles will gradually disappear from the market, which will further increase the attention to the processing of PET containers.

PET bottles are cleaned through a series of steps in caustic immersion tanks and spray stages in bottle washers. In the sink, product residue, dirt, labels and label adhesive are removed. Since the surface of PET bottles is hydrophobic, they are more difficult to clean than glass bottles. In addition, lower washing temperatures will reduce the chemical activity of the bottle wash solution.

In Laufenberg et al., "Cleaning, Sanitization and Transport of Recyclable PET" (BrewBev. Ind. Int. 1, 40-4 (References) January 1992), two principles in the PET bottle cleaning sexual issues.

In this article, the authors outline situations in which PET bottles are susceptible to corrosion or surface haze. Surface haze is caused by the chemical attack of the PET container surface by the caustic substances present in the washing bath.

A particular difficulty affecting reusable PET bottles is the presence of mold in returned bottles. Simply throwing away all the bottles that do not remove the mold is a high waste cost, 40 to 50% at certain times of the year in countries located in tropical climates.

Due to the glass transition temperature of PET, the cleaning temperature of PET bottles must be 60°C or below. If it exceeds 60°C, PET bottles will deform and shrink. The cleaning ability of bottle washing liquid at 60°C is only a quarter of that at 80°C. Recycled bottles with product residue, i.e. old bottles that have not been rinsed, will almost always be contaminated with organisms in the form of microorganisms. Bottle washes are intended to destroy microorganisms present in the bottle in the form of organisms such as bacteria, spores, mold and yeast. However, at temperatures below 60°C, cleaning and re-use of PET bottles often has persistent problems with mold.

Washing PET bottles is not as easy as washing glass bottles. Glass bottles are generally washed at 80°C. Glass bottles can also be washed with a higher concentration of caustic solution. Glass bottles can be washed by up to 5% caustic solution, and as low as 1.5% caustic solution will cause the surface haze of PET containers. For glass containers, the washing temperature, caustic solution concentration and sea washing time can be adjusted. Change as appropriate in different occasions. In contrast, PET containers cannot tolerate any of these variables at higher ranges.

Although some alternatives have been proposed, such as reducing the caustic concentration, there remains a need in the industry for compositions and methods that can be used to effectively clean PET containers and allow them to be reused multiple times.

Summary of the invention

The first aspect of the invention is a method of cleaning polyethylene terephthalate containers. The method includes: mixing the first concentrated solution and the second concentrated solution in the alkaline washing solution. The first concentrate comprises from about 0.3 to 25% by weight surfactant and from about 5 to 30% by weight acid. The second concentrate comprises from about 8 to 60% by weight builder. The method further includes contacting the PET container with a wash solution that ensures removal of soil and minimizes haze on the surface of the container.

Another aspect of the invention is a method of cleaning polyethylene terephthalate containers comprising contacting the containers with an alkaline wash at a temperature in the range from about 50°C to 60°C. The alkaline washing liquid is prepared from the first concentrated liquid, the second concentrated liquid, an alkaline source and balanced water. The first concentrate comprises a nonionic surfactant, first builder and an effective amount of acid to insure a phase stable solution. The second concentrate includes a nonionic surfactant and a second builder. The first and second concentrates are present in the wash liquor at concentrations ranging from about 0.5% to 1.2% by weight, and the first nonionic surfactant has a cloud point ranging from about 5°C to 60°C.

Another aspect of the invention is an alkaline wash for cleaning polyethylene terephthalate bottles. The lotion comprises from about 1 to 5% by weight of an alkalinity source, from about 480 to 4000 ppm of builder, from about 6 to 500 ppm of surfactant, and from about 20 to 800 ppm of coupler.

The present invention is a composition and a method for cleaning polyethylene terephthalate (PET) bottles which can improve the mildew removal effect and reduce the surface haze phenomenon. In addition to the 1 to 3% (weight) caustic solution commonly used in the cleaning process of PET bottles, the composition of the present invention also includes the combined use of surfactants and builders, which can improve the cleaning and mildew removal effects.

Surface haze is generally the result of chemical attack due to caustics present in the wash solution. Surface haze is the phenomenon that the surface of PET containers appears cloudy pattern or becomes dull, which will damage the aesthetics of the container. Surprisingly, it has been found that by using surfactants with appropriate cloud points, surface haze can be greatly reduced. Preferably, the PET container treated with the washing solution of the present invention has substantially no surface haze.

In addition, mold growth, especially in recycled PET bottles, has become a major difficulty in bottle washing. Mold is very difficult to remove, even with solutions of up to 3% caustic. A good cleaning method will usually remove most of the organic components of the mold, but inorganic residues of the mold may remain on the surface of the PET, which can create problems similar to water spots. In this case, the methylene blue coloring test will give a positive test result, (industrial test standard for refilled PET bottles, first edition (1993-1994UNESDA/CE SDA, V-18DMU)). The compositions and methods of the present invention substantially remove both organic and inorganic residues of soil and mold. Detailed Description of the Invention Composition

In a nutshell, the lotion of the present invention is prepared from two concentrated compositions, and these two concentrated compositions are mixed into a water lotion containing an alkaline source before use. These concentrate compositions generally include surfactants, acids, builders such as chelating and sequestering agents, couplers and various other auxiliaries. A. Surfactant system

in general. The compositions of the present invention include surfactants that aid in low foam cleaning operations and avoid the phenomenon of haze on PET container surfaces. Any class of surfactants may be used in accordance with the present invention, including nonionic surfactants, anionic surfactants, amphoteric surfactants, and mixtures thereof.

Nonionic surfactants include various types of polymers, specifically including but not limited to ethoxylated alkanols, ethoxylated aliphatic alcohols, ethoxylated amines, ethoxylated ether amines, carboxylates, carboxylates Acidamide and polyoxyalkylene oxide block copolymers.

Nonionic surfactants preferably used in the present invention, such as nonionic surfactants comprising ethylene oxide moieties, propylene oxide moieties and mixtures thereof and hybrid or block structured ethylene oxide-propylene oxide moieties . Another class of nonionic surfactants suitable for use in the present invention includes alkyl oxirane compounds, alkyl ethylene oxide-propylene oxide compounds and alkyl ethylene oxide-butylene oxide compounds, and mixtures thereof . The ethylene oxide-propylene oxide moieties and ethylene oxide-butylene oxide moieties may be hybrid or block structures. Another nonionic surfactant suitable for use in the present invention is any mixture of ethylene oxide-propylene oxide moieties linked to an alkyl chain, wherein the ethylene oxide and propylene oxide moieties can be any random or in an ordered manner and can be of any length ratio. Nonionic surfactants suitable for use in the present invention may also include random segments of block or hybrid ethylene oxide propylene oxide or ethylene oxide-butylene oxide.

Preferred nonionic surfactants include alkylphenols, fatty acid ethoxylates and block copolymers of ethylene oxide and propylene oxide.

Examples of nonionic surfactants that have been found suitable for use in the present invention include (EO)/(PO) block copolymers having at least about 3 molecules (EO) and at least 15 molecules (PO); Aromatic or aliphatic ethoxylates of EO), capped with or without methyl, butyl or benzyl moieties; at least about 2 molecules (EO) and from about 4 molecules (PO) of aromatic or aliphatic Ethoxylate-propoxylate copolymers, also capped with methyl, butyl or benzyl groups; and aromatic or aliphatic ethoxylates having at least about 2 molecules (EO) and about 4 molecules (BO) - Butoxylate copolymers, which can also be terminated with methyl, butyl or benzyl groups. Aliphatic groups can include any branched or linear C ₈ -C ₂₄ moieties. Aromatic groups may generally include aromatic structures such as benzyl. HLB values of 4 to 13 can also be used to characterize the surfactants used in the present invention.

Representative nonionic surfactants suitable for use in the present invention include EO/PO block copolymers available from Henkel KGaA; EO/PO block copolymers Pluronic L62 and L44 available from BASF; Fatty alcohols Tergitol 15-S-3, TMN3, TMN10; linear fatty alcohol ethoxylates Surfonic L24-1.3 from Texco Chemical CO.; nonylphenol ethoxylates such as NPE from Texaco Chemical CO. 4.5, NEP 9 and Surfonic N120; ethoxylated alkylamines such as ethoxylated cocoamine from Sherex Chemical CO. under the designation Varonic k-215; alkyl ethoxylated carboxylic acids such as Neodex 23-4 ; And benzylated fatty alcohol ethoxylates, and EO/PO block copolymers are superior to other nonionic surfactants.

Also suitable for use herein are low foaming surfactants that oil out the wash at temperatures of 59°C or below. Preferred surfactant systems include surfactants with a cloud point of from about 5°C to 60°C, preferably from about 10°C to 50°C, more preferably from about 10 to 20°C, such that in alkaline washes, the surfactant oils or Forms a film and adheres to the surface of the PET container to provide protection and avoid surface haze.

A preferred series of surfactants include butyl terminated C _12-18 fatty alcohol (EO) ₁₀ Dehyoon LT 104 and C _12-14 fatty alcohol ((EO) ₂ (PO) ₄ ) LS 24, both available from Henkel Canada Ltd. obtained.

Anionic surfactants are also useful in the present invention. Typical commercially available anionic surfactants provide carboxylate, sulfonate, sulfate or phosphate as functional anions. We have found that carboxylate-based anionic surfactants such as fatty alcohol ethoxylated carboxylates reduce surface haze on containers. One commercial source of such surfactants is Neodox 23-4 ^(TM) available from Shell Chemical CO.

Amphoteric surfactants are also useful in the present invention. Such amphoteric surfactants include betaine surfactants, sultaine surfactants, sarcosinate surfactants, amphoteric imidazolium derivatives, and the like. Some surfactants that have been found to be useful in reducing surface haze include coconut-based and lauroyl sarcosine/sarcosinates such as Hamposyl C and L available from Hampshire Chemical CO. B. Acid

The compositions of the present invention may also include a source of acid which acts to stabilize the surfactant system so that the concentrate is a true phase stable solution prior to incorporation into the wash. Once added to the alkaline rinse, the acid is neutralized into a salt that provides higher cleaning power and prevents scale formation on bottle washer parts. In general, the acid can be any kind of organic or inorganic acid.

Mineral acids useful in the present compositions and in the present invention include phosphoric acid, polyphosphoric acid or acid pyrophosphate. Organic acids suitable for use in the present invention include mono- or polycarboxylic acids such as acetic acid, glycolic acid, citric acid, gluconic acid, glucoheptanic acid, lactic acid, succinic acid, malonic acid, glutaric acid, and mixtures thereof. C. Builder

The compositions of the present invention may also include a builder, ie, chelating and sequestering agents, which inhibit the deposition of scale on the sides of PET containers and on bottle washing machines. Builders also help to suspend dirt and bind hardness ions during the washing process, which enhances cleaning. According to a particular embodiment of the invention, the first concentrate contains a first builder and the second concentrate contains a second builder.

Builders which may be used in accordance with the present invention include chelating agents including, for example, phosphonates, phosphonites, acrylates and polyacrylates, and polycarboxylates. Also suitable as builders are polymers of maleic acid and copolymers of maleic acid and acrylic acid; salts such as polyaspartic acid and polyglutarate; isoasbic acid; polyacrylamidopropyl phosphonosulfonates; and phosphinocarboxylic acids.

Water soluble acrylic polymers that may be used include polyacrylic acid, polymethacrylic acid, acrylic acid-methacrylic acid copolymers, hydrolyzed polyacrylamides, hydrolyzed methacrylamides, hydrolyzed acrylamide-methacrylamide copolymers, and mixtures thereof . Water-soluble or partially water-soluble salts of these polymers may also be used, such as the corresponding alkali metal (eg sodium or potassium) or ammonium salts.

Also suitable as builders are phosphonic acids and phosphonates. Such suitable phosphonic acids include mono-, di-, tri-, tetra-, and pentaphosphonic acids, which may contain groups capable of forming anions under basic conditions.

The phosphonic acid may also include a low molecular weight phosphonopolycarboxylic acid, such as a phosphonopolycarboxylic acid having about 2 to 4 carboxylic acid moieties and about 1 to 5 phosphonic acid groups. Such acids include 1-phosphono-1-methylsuccinic acid, phosphonosuccinic acid and 2-phosphonobutane-1,2,4-tricarboxylic acid.

Preferred chelating agents include Dequest® chelating agents available from Nonsanto CO., including aminotris(methylenephosphonic acid) pentasodium salt under the designation Dequest 2006®; 1-carboxyethylene-1 under the designation Dequest 2010, 1-diphosphonic acid; 2-phosphonobutane-1,2,4-tricarboxylic acid Bayhibit AM® from Mobay Chemical CO.; aminotris(methylenephosphonic acid) under the designation Dequest 2000®; and from Phosphonopolycarboxylic acid Belsperse 161 available from Ciba Geigy.

The builder present in both concentrates can also be a sequestering agent. Unlike chelating agents, sequestering agents help bind the alkaline earth metals present in the wash solution and bring these compounds into solution. It is thought that the inorganic salts are left behind after the mold consumes the organic part of the nutrients. Therefore, inorganic salts remaining on the surface of the PET container usually show no mildew removal effect. Sequestering agents remove these inorganic salts present in the lower layers of the mold.

The number of chains that the sequestrant can form on the monohard ion is reflected by the diligand (2), triligand (3), tetraligand (4) etc. indicated by the sequestrant. Any type of sequestrant can be used in accordance with the present invention. Representative sequestering agents include amino carboxylates, phosphonates, water soluble acrylic polymers.

Suitable aminocarboxylic acid-type chelating agents include N-hydroxyethyliminodiacetic acid, nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA), N-hydroxyethylethylenediaminetriacetic acid (HEDTA) and Diethylenetriaminepentaacetic acid (DTPA), and isoselino-N, N-diacetic acid, β-alanine-N, N-diacetic acid, sodium glycolate and tripolyphosphate are also among them. According to one aspect of the present invention, the second builder present in the second concentrate comprises an aminocarboxylic acid type sequestering agent, preferably ethylenediaminetetraacetic acid and salts thereof. D.Coupling agent

The compositions of the present invention may also include a coupling agent. The role of the coupling agent is to stabilize the concentrate composition so that it is a true phase stable solution.

For this purpose, any class of organic coupling agents can be used, including sulfate salts, sulfonates, and monofunctional and polyfunctional alcohols. Preferred coupling agents include sulfonates and sulfate ester salts such as sodium xylene sulfonate, sodium cumene sulfonate, sodium toluene sulfonate, 2-2-ylhexyl sulfate, alkyl diphenyl ether disulfonate (wherein the alkyl group is a branched C ₁₂ or linear C ₁₀ group), sodium alkylnaphthalene sulfonate, sodium octane sulfonate and sodium disulfonate, and mixtures thereof.

Such couplers which have been found to be suitable include linear alkyl alcohols such as ethanol, isopropanol and the like. Polyfunctional hydroxyl compounds such as alkylene glycols like hexanediol and propylene glycol; phosphate esters, including Gafac RP710 from Rhone-Poulence Chemicals, and Triton H-66.E.

The compositions and methods of the present invention may use any of a variety of other adjuvants such as the addition of nonionic surfactant antifoam agents such as those disclosed by Schmitt et al. in US Patent No. 5,516,451, which is incorporated herein by reference. Tracer compounds such as potassium iodide, colorants and dyes, fragrances and preservatives may also be used in other components of the invention. Instructions

The method of the invention can enhance the cleaning effect of the PET container, remove dirt, inorganic salt and mold, and at the same time suppress the haze phenomenon on the surface of the container. This result is achieved by formulating a first acidic concentrate containing a high concentration of surfactant with a second concentrate containing a high concentration of builder.

According to one aspect of the invention, the first concentrated solution and the second concentrated solution may be incompatible if mixed separately from the wash solution. The incompatibility in this case is due to the different pH values required of the two different concentrates. The pH of the first concentrate is generally less than 2 to maintain the stability of the surfactant system. The pH value of the second concentrated solution is selected under the condition that the builder can be completely dissolved, and is generally alkaline. Mixing of the two concentrates prior to dilution in the wash liquor can lead to phase separation of the surfactant system or builder, depending on the pH.

In use, the two concentrates are mixed into the alkaline washing system, which can provide high cleaning efficiency with good washing effect. The following examples illustrate the respective concentration ranges for the two concentrates:

Table 1 Concentration (wt-%) Concentrate 1 Be applicable preferred more preferred Surfactant system 0.3-25 1-15 3-10 first builder 0-20 5-20 10-20 Coupler 1-40 30-20 5-15 Acid (100% w/w) 5-30 10-20 10-15 water Sufficient Sufficient Sufficient Concentrate 2 Surfactant system 0-10 0.1-5 01-1 second builder 8-60 15-45 30-45 water Sufficient Sufficient Sufficient use liquid Surfactant 6-500 20-300 60-200 builder 480-4000 1000-3000 2000-3000 water 20-8 60-400 100-300

In use, the system is diluted to a wash solution comprising from about 0.1% (weight) to 0.8% (weight) and preferably from about 0.1% (weight) to 0.3% (weight) of the first concentrate and from about 0.2 to 1.2% by weight and preferably from 0.4 to 0.8% by weight of the second concentrate. The ratio of the first concentrate to the second concentrate in the alkaline wash typically ranges from about 0.1:0.5 to 0.1:1.0, and preferably from about 0.1:0.2 to 0.15:0.3. Generally, the alkaline wash may contain from about 0.3 to 2.0% by weight and preferably from about 0.5 to 1.2% by weight of Concentrate 1 and Concentrate 2 in total.

According to a preferred aspect of the present invention, the lotion comprises at least about 1000 ppm EDTA, at least about 5 ppm phosphonate compounds and at least about 100 ppm gluconate compounds.

Washing of PET containers is generally carried out in several steps. The PET container is first emptied and pre-rinsed, then soaked in the wash solution. The wash liquor generally always contains from 1.0 to 5% by weight and preferably from about 1.5 to 3% by weight caustic (NaOH). Mix Concentrate 1 and Concentrate 2 into this system, and immerse the PET container in it. The washing process lasts for a period of time from about 7 to 20 minutes. The washing temperature is about 59°C±1°C. The vessel then goes through a mildly caustic treatment stage where water is passed into a wash tank for continuous cleaning and rinsing is initiated by reducing the concentration of sodium hydroxide. Caustic concentration can be maintained by conductivity controller. The containers then go through at least three rinsing stages, first with hot water, then with cold water, and finally with potable water, after which the containers are vertically stacked, accepted and filled.

Example

The following working examples illustrate the invention in a non-limiting manner. Working Example 1

The degree of surface haze was investigated using the different compositions listed below.

The examples provided in Table 2 below were tested with other compositions in Table 3.

Table 2 components Example Example 1A 1B H ₃ PO ₄ (75%)w/w 10.0 Gluconic Acid (50% w/w) 10.0 Dehypon LT-104 (C _12-18 H _24-37 (EO) ₁₀ O _n C ₄ H ₉ ) 11.00 Dehypon LS-24 (C _12-14 H _25-29 (EO) ₂ (PO) ₄ OH) 5.0 Trition BG-10 (Alkyl Polyglucoside) 1.00 Dequest 2000® (50% w/w) (aminotrimethylene phosphonic acid) 6.00 6.00 Dequest 2010 (60% w/w) (1-hydroxyethylidene-1,1-diphosphonic acid) 2.00 Bayhibit-AM® (50% w/w) (2-phosphonobutane-1,2,4-tricarboxylic acid) 3.00 Tetrasodium EDTA (powder) 39.00 Sodium cumene sulfonate (40% w/w) 30.00 VN-11 (oleyl alcohol diethylene glycol) 0.50 potassium iodide 0.25

The extent of surface chemical haze was investigated using PET specimen strips (0.5" x 2") cut from amorphous (low crystallinity) PET sheets. The specimens were immersed in approximately 200 ml of a 2.8% caustic solution containing the various amounts of additives tested. The solution was shaken at a speed of 100rpm for 24-72 hours in a water bath maintained at a temperature between 58-60°C. ) as a reference standard, visual inspection and gravimetric evaluation.

table 3 Example active ingredient concentration surface haze 1A Table 2 0.05wt-% 0.5 1A Table 2 0.2wt-% 0.5 1A Table 2 0.6wt-% 0.5 1A Table 2 2.0wt-% 0.5 1B Table 2 0.05wt-% 10 1B Table 2 0.1wt-% 7.5 1B Table 2 0.2wt-% 5.5 1B Table 2 0.35wt-% 1.5 1C Dehypon LT104 (C _12-18 H _24-37 (EO) ₁₀ OC ₄ H ₉ 10ppm 0 1D Dehypon LS24 (C _12-14 H _25-29 (EO) ₂ (PO) ₄ OH) 10ppm 1 1E Triton BG-10 (Alkyl Polyglucoside (70%W/W)) 300ppm 8 1F Alkyl polyglucoside 500ppm 10 1G Sodium cumene sulfonate 300ppm 9 Contrast 1 water 0wt-% 0 Contrast 2 caustic 2.8wt-% 10 The degree of surface haze is measured against a value of 0 when washing with water and a value of 10 when washing with 2.8% caustic when no surface haze occurs. Examples 1C and 1D, and a series of experimental tests of Example 1A demonstrate that these compositions, whether used alone or in combination with a chelating agent, are very effective in preventing surface haze. Working example 2

Adopt the method of embodiment 1, carry out the second group analysis (comparative test except) to the surface haze that wherein contains each active component (embodiment 2A-2W) and 2.8% (weight) NaOH washing water to cause second group analysis, result report in Table 4.

Table 4 Example active ingredient surface haze 2A (PO) ₂₄ (EO) ₁₅ [(PO) _13.0 (EO _15.5 )](EO) ₁₅ (PO) ₂₄ 0 2B (PO) ₁₃ (EO) ₁₅ [(EO) _2.2 (PO _25.5 )](EO) ₁₅ (PO) ₁₃ 0 2C (PO) ₅ (EO) ₁₅ [(PO) _13.0 (EO _15.5 )](EO) ₁₅ (PO) ₂₄ 1 2D Pluronic L62 HO(EO) ₁₁ (PO) ₃₀ (EO) ₈ H 0 2E Pluronic L44HO(EO) ₁₁ (PO) ₂₁ (EO) ₁₁ H 0 2F Tergitol 15-S-3 (C _11-15 H _23-31 (EO) ₃ OH) 0 2G Tergitol TMN3 (C ₁₂ H ₂₅ (EO) ₃ OH) 0 2H Tergitol TMN10 C ₁₂ H ₂₅ (EO) ₁₀ OH 0 2I Surfonic L24-1.3 (C _12-14 (EO) _1.3 OH) 0 2J Plurafac LF131 (C _12.7 (EO) ₇ (BO) _1.7 OCH ₃ ) 15 2K Dehypon LT104 (C _12-18 H _24-37 (EO) ₁₀ O _n C ₄ H ₉ 0 2L (C ₆ H ₅ CH ₂ )-(PO) ₁₃ (EO) ₁₅ [(EO) _2.2 (PO) _25.5 ](EO) ₁₅ (PO) ₁₃ -(CH ₂ C ₆ H ₅ ) 0 2M C _12-14 O(EO) _10-12 -CH ₂ C ₆ H ₅ 0 2N NPE4.5 Nonylphenol (EO) _4.5 2 2O NPE9.5 Nonylphenol (EO) _9.5 0 2P Surfonic N120 C ₉ H ₁₉ C ₆ H ₄ (EO) ₁₂ OH 6 2Q Neodox 23-4 (C _12-13 (EO) ₄ OCH ₂ COOH) 4 2R Varonic K215 (coconut amine ethoxylate (EO) ₁₅ ) 4 2S Hamposyl C Cocoyl Sarcosine (C _12-18 H _25-37 C(O)N(CH ₃ )CH ₂ COOH) 1 2T Hamposyl L Lauroyl Sarcosine 4 2U Hamposyl L30 Sodium Lauroyl Sarcosinate 10 2V Silwet L77(CH ₃ ) ₃ SiOSi[(CH ₃ )OSi(SH ₃ ) ₃ ][(CH ₂ ) ₃ (EO) ₈ OCH ₃ ] 5 2W 2.8% NaOH (comparison) 10 Working Example 3

Test coupons (approximately 2" x 3") were cut from contaminated bottles collected from the field. The wash test was carried out in 1000 ml of solution under agitation (500 rpm) for 10 minutes, followed by a water rinse (8 psi nozzle spray, sprayed down from the top) for 1 minute. According to the industrial test standard for refilled PET bottles, the first edition (1993-1994UNESDA/CESDA), page V-18, using the methylene blue staining test to evaluate the dirt level before and after cleaning, for 20 minutes and 30 minutes cycle cleaning In terms of process, repeat the above steps every 10 minutes. The wash solution included 2.8% by weight caustic, 0.6% by weight of Example 1B and varying amounts of Example 1A as shown in Table 5 below. A group of four samples was used for statistical averaging. Data reported as total swatches cleaned/total swatches washed.

Table 5A 2.8% caustic 0.6% Example 1B Cleaning time Example 1A (wt-%) 10min 20min 30min

0.06 1/4 1/4 2/4

0.10 1/4 2/4 2/4

0.15 2/4 3/4 3/4

0.20 2/4 2/4 3/4

0.25 3/4 3/4 3/4

0.30 4/4

Table 5B

In this example, the wash solution included 2.8% by weight caustic and 0.2% by weight of Example 1A, as well as various amounts of Example 1B as shown in the table below. Data are reported below in the same manner as in Table 5A.

Example 1B of cleaning time (wt-%) 10min 20min 30min

0.60 2/4 2/4 2/4

1.20 4/4

0.80 4/4

Table 5C

Various concentrations of Examples 1A and 1B were mixed to test cleaning efficacy. Report data results in Tables 5A and 5B.

Cleaning Time Example 1A (wt-%) Example 1B (wt-%) 10min 20min 30min

0.10 1.20 3/4 3/4 3/4

0.15 1.20 3/4 3/4 3/4

0.20 1.20 4/4

0.10 1.80 3/4 3/4 3/4

0.15 1.80 3/4 4/4

0.20 1.80 4/4

0.20 0.7 2/4 2/4 3/4

0.20 0.8 2/4 2/4 3/4

0.20 1.0 4/4

0.30 0.4 2/4 2/4 2/4

0.40 0.4 2/4 2/4 2/4

Table 5D

The cleaning efficacy of the washing solutions containing the set concentrations of Example 1A and Example 1B and different concentrations of caustic was analyzed. Example 1A was added to the wash at 0.2% by weight and Example 1B was added to the wash at 0.8% by weight, and the results are reported below in the same manner as in Tables 5A-5C.

                  

Caustic (wt-%) 10min 20min 30min

1.5 2.4 2.4 3/4

2.0 2/4 2/4 4/4

2.6 3/4 3/4 4/4

The above specification, examples and data provide a complete description of the manufacture and use of the compositions of the invention. As many embodiments of the present invention are possible without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.

Claims (59)

1. method that cleans the ethylene glycol terephthalate container, described method comprises the steps:

First concentrated solution and second concentrated solution are incorporated in a kind of alkaline rinse:

(a) described first concentrated solution comprises:

(i) from the tensio-active agent of about 0.3 to 25% (weight); With

(ii) from the acid of about 5 to 30% (weights);

(b) described second concentrated solution comprises:

(i) from the washing assistant of about 8 to 60% (weights);

Described method further comprises the step that described container is contacted with described washing lotion, removes dirt and can make the surperficial optical haze phenomenon of container the lightest simultaneously in this step.

2. the process of claim 1 wherein that described first concentrated solution comprises first washing assistant, described second concentrated solution comprises second washing assistant.

3. the process of claim 1 wherein that described second concentrated solution further comprises a kind of tensio-active agent.

4. the process of claim 1 wherein the first concentrated solution concentration range that adds described washing lotion be washing lotion from about 0.1% (weight) to 0.8% (weight).

5. the process of claim 1 wherein add the second concentrated solution concentration range in the washing lotion be washing lotion from about 0.2% (weight) to 1.2% (weight).

6. claim 4 or 5 method, wherein first concentrated solution and the ratio of second concentrated solution in washing lotion are from about 0.1: 0.5 to 0.1: 1.0 scope.

7. the process of claim 1 wherein that washing lotion comprises described first and second concentrated solutions from about 0.3% (weight) to 2.0% (weight).

8. the process of claim 1 wherein that alkaline rinse comprises the alkaline source from about 1% (weight) to 5% (weight).

9. the method for claim 8, wherein said alkaline source comprises the causticity thing of about 1.5% (weight) to 3% (weight).

10. the process of claim 1 wherein that described first concentrated solution further comprises a kind of coupler.

11. the method for claim 10, wherein said coupler are selected from sodium xylene sulfonate, 2-ethylhexyl sulfuric acid, cumene sodium sulfonate, toluenesulfonic acid sodium salt, sodium alkyl naphthalene sulfonate, perfluorooctane sulfonate, branched-alkyl phenyl ether stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate, linear alkyl phenyl ether disulfonate salt and their mixture.

12. the method for claim 10, wherein said coupler comprises a kind of multifunctional hydroxy compounds.

13. the method for claim 10, wherein said washing lotion comprises a kind of phosphoric acid ester.

14. the process of claim 1 wherein that described washing lotion temperature is from about 50 to 70 ℃.

15. the process of claim 1 wherein that described washing lotion temperature is lower than 60 ℃.

16. the process of claim 1 wherein that described Surfactant agent is selected from nonionogenic tenside, anion surfactant, amphoterics and their mixture.

17. the process of claim 1 wherein that described tensio-active agent comprises a kind of nonionogenic tenside.

18. the method for claim 17, wherein said nonionogenic tenside are selected from ethylene oxide-propylene oxide block copolymer, alkylethoxylate, alkyl ethoxy-propoxylated glycerine, alkyl ethoxy-butoxy thing and their mixture.

19. the method for claim 2, wherein said first washing assistant is selected from phosphonate, phosphinate, acrylate, multi-carboxylate and their mixture.

20. the method for claim 2, wherein said second washing assistant comprises the sequestering agent of ethylenediamine tetraacetic acid (EDTA) or its salt.

21. the method for claim 2, wherein said second concentrated solution is incompatible with described first concentrated solution.

22. the method for claim 21, wherein said second washing assistant comprise a kind of alkylene polyamine polyacetic acid salt.

23. the process of claim 1 wherein that described acid is selected from organic acid, mineral acid and their mixture.

24. comprising, the method for claim 23, wherein said acid be selected from citric acid, acetate, hydroxyethanoic acid, glyconic acid, glucoheptonic acid, lactic acid and their mixture.

25. the method for claim 17, the cloud point of wherein said nonionogenic tenside in alkaline rinse is from about 5 ℃ to 60 ℃ scopes.

26. the process of claim 1 wherein that described polyethylene terephthalate container does not have mould after washing.

27. by the washing lotion that claim 1 method obtains, described washing lotion comprises from about 6 to 500ppm tensio-active agents, from about 480 to 4000ppm washing assistants with from about 20 to 800ppm couplers.

28. method that cleans poly terephthalic acid ethylene alcoholester container, described method comprises that with described container and a kind of temperature 50 ℃ of steps that contact to the alkaline rinse of 60 ℃ of scopes, described alkaline rinse is formulated by first concentrated solution, second concentrated solution, alkaline source and equilibrium water;

(a) described first concentrated solution comprises a kind of nonionogenic tenside, first washing assistant and the significant quantity acid of stabilizing solution mutually can be provided; With

(b) described second concentrated solution comprises a kind of nonionogenic tenside and second washing assistant, and the concentration of second concentrated solution that exists in the washing lotion from about 0.3% (weight) to 2.0 (weight) scope, the cloud point scope of described first nonionogenic tenside is from about 25 ℃ to 60 ℃.

29. the method for claim 28, wherein

(a) described first concentrated solution comprises:

(i) from described first nonionogenic tenside of about 1 to 15% (weight);

(ii) from described first washing assistant of about 5 to 20% (weights); With

(iii) from the described acid of about 10 to 20% (weights); With

(b) described second concentrated solution comprises

(i) from described second nonionogenic tenside of about 0.1 to 5% (weight); With

(ii) from described second washing assistant of about 15 to 45% (weights).

30. the method for claim 29, the first concentrated solution concentration range that wherein adds described washing lotion be washing lotion from about 0.1% (weight) to 0.8% (weight).

31. the method for claim 29, wherein add the second concentrated solution concentration range in the washing lotion and be washing lotion from about 0.2% (weight) to 1.2% (weight).

32. the method for claim 30 or 31, wherein first concentrated solution and the ratio of second concentrated solution in washing lotion are from about 0.1: 0.5 to 0.1: 1.0 scope.

33. the method for claim 28, wherein washing lotion comprises described first and second concentrated solutions from about 0.3% (weight) to 2.0% (weight).

34. the method for claim 28, wherein alkaline rinse comprises the alkaline source from about 1% (weight) to 5% (weight).

35. the method for claim 28, wherein said alkaline source comprise the causticity thing of about 1.5% (weight) to 3% (weight).

36. the method for claim 28, wherein said first concentrated solution further comprises a kind of coupler.

37. the method for claim 36, wherein said coupler are selected from sodium xylene sulfonate, 2-ethylhexyl sulfuric acid, cumene sodium sulfonate, toluenesulfonic acid sodium salt, sodium alkyl naphthalene sulfonate, perfluorooctane sulfonate, branched-alkyl phenyl ether stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate, linear alkyl phenyl ether disulfonate salt and their mixture.

38. the method for claim 36, wherein said coupler comprises a kind of multifunctional hydroxy compounds.

39. the method for claim 36, wherein said washing lotion comprises a kind of phosphonic acid ester.

40. the method for claim 28, wherein said washing lotion temperature is from about 50 to 70 ℃.

41. the method for claim 28, wherein said washing lotion temperature is lower than 60 ℃.

42. the method for claim 28, wherein said Surfactant agent is selected from nonionogenic tenside, anion surfactant, amphoterics and their mixture.

43. the method for claim 28, wherein said second washing assistant is incompatible with described first concentrated solution.

44. the method for claim 43, wherein said second washing assistant comprise a kind of alkylene polyamine polyacetic acid salt.

45. the method for claim 28, wherein said acid are selected from organic acid, mineral acid and their mixture.

46. comprising, the method for claim 45, wherein said acid be selected from citric acid, acetate, hydroxyethanoic acid, glyconic acid, glucoheptonic acid, lactic acid and their mixture.

47. the method for claim 28, the cloud point of wherein said nonionogenic tenside in alkaline wash from about 10 ℃ to 50 ℃ of scopes and composition thereof.

48. the method for claim 28, wherein after washing, described polyethylene terephthalate container does not have mould.

49. the washing lotion that obtains by claim 28 method, described washing lotion comprises from about 6 to 500ppm tensio-active agents, at least about described first washing assistant of 5ppm, described first washing assistant comprises phosphonate compounds and at least about described second washing assistant of 1000ppm, described second washing assistant comprises ethylenediamine tetraacetic acid (EDTA) or its salt.

50. an alkaline rinse that is used for cleaning the polyethylene terephthalate bottle, described washing lotion comprises the mixture of being made up of following compound:

(a) from about 1 to 5% (weight) alkaline source;

(b) from about 480 to 4000ppm washing assistants;

(c) from about 6 to 500ppm tensio-active agents; With

(d) from about 20 to 800ppm couplers.

51. the washing lotion of claim 50, wherein alkaline rinse comprises the alkaline source of about 1.5% (weight) to 3% (weight).

52. the washing lotion of claim 50, wherein said coupler is selected from sodium xylene sulfonate, the own sulfuric acid of 2-ethyl, cumene sodium sulfonate, toluenesulfonic acid sodium salt, sodium alkyl naphthalene sulfonate, perfluorooctane sulfonate, branched-alkyl phenyl ether stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate, linear alkyl phenyl ether disulfonate salt and their mixture.

53. the washing lotion of claim 50, wherein said coupler comprise that a kind of multifunctional hydroxy closes.

54. the washing lotion of claim 50, wherein said coupler comprises a kind of phosphonate compounds.

55. the washing lotion of claim 50, wherein said tensio-active agent comprises a kind of nonionogenic tenside.

56. the washing lotion of claim 55, wherein said tensio-active agent are selected from ethylene oxide-propylene oxide block copolymer, alkylethoxylate, alkyl ethoxy-propoxylated glycerine, alkyl ethoxy-butoxy thing and their mixture.

57. the method for claim 50, wherein said first washing assistant is selected from phosphonate, phosphinate, acrylate, multi-carboxylate and their mixture.

58. the method for claim 50, wherein said washing assistant comprise ethylenediamine tetraacetic acid (EDTA) or its salt.

59. the washing lotion of claim 50 comprises at least about 1000ppm ethylenediamine tetraacetic acid (EDTA) or its salt, at least about the 5ppm phosphonate compounds with at least about 100ppm gluconate compound.