DE2457132A1 - OVEN CLEANING PRODUCTS, METHODS FOR THEIR PRODUCTION AND METHOD OF APPLICATION - Google Patents

Description

PATENTANWÄLTE f \ I P Π Λ

PROF. DR. DR. J. REITSTÖTTER ά H \) I I

DR.-ING. WOLFRAM BUNTE DR. WERNER KlNZEHACH

D-βΟΟΟ MUNICH 4O. BAUERSTRASSE 22 FERNRUF (Οββ) 37 05 83 TEUEX 5210ZO8 ISAR D POSTAL ADDRESS: D-βΟΟΟ MUNICH 43, POST BOX 7βΟ

Munich, December 3, 1974 M / 15 576

BRISTOL-MYERS COMPANY

345 Park Avenue,

New York, N.Y. / V.St.v.A.

Oven cleaning agents, process for their preparation and application method

The invention "relates to oven cleaners. In particular "It concerns oven cleaners that are low in concentration have caustic alkali and still have a cleaning ability, the common oven cleaners with a high content of caustic alkali is the same.

ovens are subject to heat and can be baked on organic deposits, which generally consist of a complete

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ι xen organic mixture of natural fats and other ma-

] materials that result from cooking food spoil

i be cleansed. When heated to normal oven temperatures

these dirt deposits are transformed into an infusible poly-

j mere mass transferred, in which part of the organic mass

J terials can also be charred. Although. Detergents,

Scouring powder and similar cleaning products in the

; removal of normal greasy contaminants

j are very effective, they are usually for removal

'< of baked-on impurities from what was found in ovens

Type not appropriate.

j The removal of this type of pollution _t is a

! serious problem. Usually is a strong one

j chemical or physical action required. to

i the most effective chemical compounds known for this purpose include caustic alkalis, such as sodium or potassium

j hydroxyd. You can go straight through a brush or a

j sponge, or more conveniently with an aerosol spray.

j be brought. Although products of this type are effective

j, they still show a number of essential evidence

j split up. When used on dirty,

j oven surfaces attack such products the pollution

! from the outer surface. The strongest char

ι and polymerization is, however, in general

I inside the polluting layer, adjacent to it

j the furnace wall. This makes cleaning difficult. In addition,

• require caustic alkalis and common oven cleaning agents

I be with high concentration of caustic alkali when using them

! Considerable safety precautions. Thus the advantage is

I obviously who in creating an effective furnace

i cleaning agent with a low content of caustic alkali

! will create.

! Alkalis that are less alkaline than caustic alkalis are for

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rapid hydrolyzing of baked-up deposits are not very effective and consequently are not effective oven cleaning agents. middle.

Various cleaning agents are known in the art for hard surfaces or ovens that use caustic alkali as the primary cleaning ingredient. U.S. Patent No. 3,715,324 discloses an oven cleaner that is $ 10 to $ 40 Sodium Hydroxide- in addition to other ingredients, including Triethanolamine. U.S. Patent No. 2,992 and U.S. Patent No. 2,097,737 disclose metal cleaners, at least $ 10, or $ 6, of an alkali metal hydroxide in addition to other ingredients including alkanolamines ^. However, these patents disclose not the agents according to the invention with a low content of caustic alkali.

From the prior art, a number of oven cleaning compositions are disclosed which use down to 1 ° / o caustic alkali; However, these agents contain additional components for cleaning which are not included in the agents according to the invention. For example, U.S. Patent No. 3,644,210 discloses an oven cleaner containing from 1 to 20% of an alkali metal hydroxide, an ethoxylated alkanolamide, and numerous other ingredients which can all be replaced by the alkali metal hydroxide. U.S. Patent No. 3,625,859 discloses an agent containing caustic alkali and an alkali metal or ammonium salt of a styrene-maleic anhydride copolymer. US Pat. No. 3,031,408 discloses an agent which additionally contains an alcoholic solvent, a flow reducer and an amphoteric detergent. US Pat. No. 3,591,416 discloses an oven cleaner composed of 99% sodium nitrate and 1% sodium hydroxide.

³ 6AD ORIGINAL '

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retroactively

2A57132 "

. ... M / 15 576

South African Patent Specification No.% & 54q4 ~ jQ- discloses a

Oven cleaner that does not contain alkali and that essentially consists of primary, secondary or tertiary amines as the main source of alkali.

None of these prior art patents disclose the oven cleaning agents according to the invention, namely agents containing an alkanolamine and a low concentration of one Contain alkali metal hydroxide. Oven cleaners containing an alkali metal hydroxide, an alkanolamine and an alkyl glycolaryl ether are known. However, as described in U.S. Patent No. 3,662,447, the alkanolamine and the alkylene glycol aryl ether for use as "accelerators" combined to increase the effectiveness of the alkali metal hydroxide. In addition, in That patent specifically states that when the alkanolamine is used without the ether, it essentially does so has no accelerating effect on the alkali metal hydroxide.

The oven cleaning agents disclosed in the prior art or known in the oven cleaning field thus take the use of an alkanolamine in conjunction with a low concentration of an alkali metal hydroxide to create an oven cleaner that is as effective as conventional oven cleaners high concentrations of caustic alkali, neither in advance nor suggest it.

In accordance with the present invention, oven cleaners are provided which contain about 0.5 % to about 4.0 %, preferably about 1.5% to about 3.7%, of an alkali metal hydroxide, about 1.0% to about 20.0% , preferably about 3 $ to about 15 ^ of an alkanolamine, selected from monoethanolamine, aminoethylethanolamine, monoisopropanolamine,

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! Ν, Ν-diethylethanolamine, N-methylethanolamine, diglycolamine, diisopropanolamine, triisopropanolamine, isopropanolamine, dimethylethanolamine, Ν, Ν-diisopropylethanolamine, diethanolamine, N-methyldiethanolamine and N-ethyldiethanolamine, and; "up to about 98.5 #, preferably up to about 95» 5 ^ ^; water, all on a weight basis.

Ils preferred embodiment of the furnace according to the invention: cleaner means is provided which approximately j 2.0 ° / o of sodium hydroxide, about 5.0 $ monoethanolamine, un-; dangerous 2.5 ^ bentonite, about 1.0 f "a coconut oil

fatty acid, about 1.5 i »one. Isobutane-n-Batan propellant-I comprises means and up to about 88.0 $ ,,, water ■ in each case based on the weight.

I As a further preferred 'embodiment of the invention

. MAESSEN oven cleaning means is further provided a means which about 2.0 ^ sodium hydroxide, about 10.0 ia monoethanolamine, about 2.5 ^ bentonite, about 1.0% of a Kolcosnußfettsäure, about 1.5 ^ one iso-

: butane-n-butane propellant and up to about 83.0 # water, each based on weight.

The present invention also provides a process for the 'production of oven cleaners, characterized gekennzeich-: net that is about 0.5 i ° to about 4.0%, preferably from about 1.5 $> to about 3.7 # each based on the weight of an alkali metal hydroxide and about 1.0% to about 20.0% , preferably about 3 to about 15% by weight of an alkanolamine selected from

i. ■

j monoethanolamine, aminoethylethanolamine, monoisopropanol

j amine, Ν, Ν-diethylethanolamine, N-methylethanolamine, ΜΙ glycolamine, diisopropanolamine, triisopropanolamine, isoi propanolamine, dirnethylethanolamine, Ν, Ν-diisopropylethanolamine, Diethanolamine, N-Methyldiethanolamine and N-Ethyldi-

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Ethanolamine up to about $ 98.5, preferably up to about $ 95.5 water mixed.

The present invention also provides a cleaning method for removing caked organic debris from j a furnace surface, which is characterized in that j a furnace according to the invention is used for a certain time ! allows cleaning agent to act on the deposits.

ί Some of the advantages offered by the furnace according to the invention

I detergents are a lessening

j the concentration of caustic alkali and increased cleaning.

The oven cleaning agents according to the invention .can be numerous contain additional ingredients that help create an effective oven cleaner, such as

. Bentonite, coconut oil fatty acid, lauryl alcohol and leavening agents. Bentonite is useful as a thickener and helps prevent the oven cleaner from draining off prevent cleaning surface. Since an oven has both vertical and horizontal surfaces, the concentration of thickener can be varied to create an effective medium for the agent so that all Oven surfaces can be cleaned effectively. Other thickeners that can be used include: Polyoxyethylene compounds, carboxymethyl cellulose or titanium dioxide. Numerous soaps and detergents, such as coconut oil fatty acid soaps, Aluminum stearate and the like can be used in of the present invention can be used to increase the solubility of the ingredients. Examples of solubility-increasing Agents and additives that can be used include lauryl alcohol, methyl cellulose, and 1,1,1-trichlorethylene. Propellants that can be used in the agents according to the invention include, for example, propane, pentane, Butane and the halogenated hydrocarbons. The present invention is not specific to any of these listed additives are limited, as numerous other furnace

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! Cleaning additives can also be used.

To determine the effectiveness of the furnace according to the invention

reiniguj

turns.

j cleaning agents, the following working methods were used.

First became a kind of furnace contamination as in the following Table I, which is typical of the contaminants encountered in household stoves.

TABLE I. component weight of loading G part G Peanut oil 45 G Corn oil 25th G Cherry pie mix 2.5 G Minced beef 25th G Minced pork 25th g. Sodium chloride 1 G Sodium glutamate 1 water 25th

The ingredients shown in Table I were mixed in a pan and cooked for two hours at 204.4 ⁰ C (400 ⁰ P) in an oven. The cooked material was filtered through glass wool and stored in a glass bottle. The bottle was shaken before testing.

The effectiveness of an oven cleaner depends on it

the type and nature of the stain to be removed. Dalier

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is after applying the soil composition to a Test surface the hardening of importance. Approximately 0.28 "to 0.30 g of the above contaminant was added to a 4 1/2 "χ 4 1/2» (11.43 x 11.43 cm) porcelain test plate applied and as evenly as possible with a flat

j Spread the spatula over the surface of the pollution plate.

Pollution material was added to or from the pollution plate removed until 0.25 g of dirt

j material remained.

De manner hardened and - as explained below - was j curing for various times and at various temperatures, performed to contamination induce which were difficult to remove ^{miscellaneous:} ■ The pollution plates were in the furnace to the subsequent. \ Six pollution plates were \ be taken into a baking pan. Another baking pan was used as a lid. '■ The pan and lid were tightly closed with hand-tightened' screws and wing nuts. Since stuck; it was established that air currents maintain the uniformity of the

■ affect hardened pollution, the pan and were the lid is sealed with aluminum foil. Three sets of

; Pans and lids (each containing six porcelain test plates) were placed on the three compartments (1 set on each compartment) of a "Blue M" Model OV-49O-A-2 constant temperature oven and at a specified temperature. hardened for a certain time. The furnace temperature was exactly to approximately -1.1 ⁰ C (-2 ⁰ F). The oven was set to the required temperature, then the oven door was opened and the pans were placed in the oven as quickly as possible. The time measurement was with the closing; the oven door has started. This meant that at the beginning of curing the oven temperature was below the thermostat! setting lay. After the required time, the pans were removed from the oven and allowed to cool to room temperature

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calmly. The pollution plates were then off the pans removed. Despite all precautionary measures, the hardened impurities were generally not complete evenly. Some pollution panels had areas where there was very little pollution and other areas with greater pollution. The panels with extreme pollution density variations were removed. . . ·

The oven cleaning agents according to the invention examined contain the components listed in Table II:

TABLE II

Ingredient Wt .- $ participate in stock

Bentonite '2.5

Sodium hydroxide *

Monoethanolamine *

Coconut Oil Fatty Acid 1.0

50/50 isobutane / n-butane 1.5

Water (deionized),

as much as required to a total of 100%

* The weight percent of this ingredient has been varied to reflect its effective range in the oven detergent ascertain.

j The oven cleaning agents were in 300 g batches as follows

ι produced: The approximate weight of the aqueous bentonite con-

Zentrats (measured in such a way that a final bentonite concentration

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j tion of 2.5 % was obtained) was poured into a 500 ml alder. Naeyer flask weighed in, into which a Teflon-coated

I was given a 5 »08 cm (2nd inch) magnetic stir bar.

I Additional water was added as needed.

The sodium hydroxide and the dispersion were then added

j was stirred 'until it was even. The monoethanolamine

: was added and the dispersion was briefly stirred. At-

The coconut oil fatty acid was then added and the mixture was stirred

! Disperse again until uniform. 200 g of the

j I

I tels were weighed into an aerosol container. The container was sealed and with 3 g of a propellant mixture under

j pressure set. The funds were either made under

i pressurized and used immediately, or prepared j and overnight at about 29.4 ⁰ C (85 ⁰ I ¹ ) in a sealed,

i stored and unpressurized aerosol containers

_; pressurized before use.

h ; Each. Oven cleaner was tested on the 4 1/2 "4 1/2" porcelain soiling panels.

' Preliminary tests have been carried out on the funds

i on the pollution plates instead of by spraying as Aerosol were applied with a parquet brush. It was

¹ found that cleaning was less than that of aerosol treatment. All other tests were done with aerosol treatment. Since a housewife is concerned not with the amount (ie weight) of soil remaining in her oven after cleaning but with the area of the oven on which soil remains after cleaning, the term "percent soil" has been used as The percentage of the area of the 11.43 cm by 11.43 cm (4 1/2 "by 4 1/2") debris panel that was free of debris after cleaning. The percent cleaning for each soiling panel was determined by visual inspection. The same person in each case determined the percentage cleaning of all soiling plates in order to

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Eliminate ending bias.

One factor that was considered was accuracy in the Assessment of the percentage cleaning of each soiling plate. Table III below shows the observed accuracy in plotting the mean percent cleaning the pollution plates.

TABLE III Accuracy
area io cleaning - 0.5 io 0-2 ". - ■ - ι io 2 - 10 ± 3 ok 10-30 - 5 ok 30-80 ■ - λ io 80-90 - ο, 7 i> 90-95 - 0.5 i » 95-100

ι Where the range of accuracy in determining the! percentage cleaning was very critical, for example at; O to $ 2> and $ 95 to $ 100, the number of I pollution plates examined was increased in order to increase the reliability of the! ensure original tests.

j As previously stated, the difficulty in developing ; removal of a pollution by the conditions used in curing the pollution, i.e. the period of time

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Hardening and the hardening temperature. To illustrate the effectiveness of the oven cleaners of the present invention, soils with varying degrees of difficulty to remove were prepared as shown in Table IV below. These soiling plates were treated with a 3 " sodium hydroxide solution for a period of 6 hours, rubbed gently with a sponge and then rinsed with cold water. In all of the following examples, the percentages of sodium hydroxide listed are the percentages added to the agents constant amount (1%) is added to coconut oil fatty acid for each agent can be neutralized by the fatty acid of the Natriumhydroxyds i 0.15 °. Thus, the percentage content of active sodium in all listed agents $ 0.15 is less than the specified number (ie a 3% sodium hydroxide test solution contains 2.85% free sodium hydroxide). In all of the oven cleaning tests described below, only the variables, namely the alkali metal hydroxide or the alkanolamine, are listed. It should be noted that the remaining components of the oven cleaning agent are kept constant and as in the table II described, procure are.

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TABLE IV

ι Effect of the curing conditions in simulierj soiling of the oven

Test composition: 3 # NaOH Experiment No. ' 1 2 3

! Curing time

j (hrs.) 1.0 1.25 1.25 2.0 1.5

_; Curing temp.

⁰ C ( ⁰ E) 218.3 232.2 237.8 232.2 246.1

(425) (450) (460) (450). (475)

■ Response time

^: (Hours) 6 6 6 -'6 6

^: Removal of the

Pollution '

(f) 99.6 '94.8 89.0 70.0 ^ 50-60

The results listed in Table IV that a hardened at 218.3 ⁰ C (425 ° P) for one hour pollution plate by 6-hour treatment at room temperature with a 3 $ sodium hydroxide solution is easily cleaned. By increasing the curing temperature to 232.2 ⁰ C (45O ⁰ P) and the curing to 1.25 hrs., The cleaning effect decreases (namely, the percentage of soil removal) to 94.8 i> ab. The effect of curing time is shown in Runs 2 and 4 where the curing temperature was maintained at 232.2 ⁰ C (45O ⁰ P), the curing time was extended to 2 hrs.. In this pail, the percent contamination removal is reduced from 94.8 # to 70.0 #. In contrast, the effect is an increase in the curing temperature by 5.5 ⁰ C (10 ⁰ P) maintaining a untex

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Curing time of 1.25 hours in test 3 shown. In this case the percentage removal of pollution of 94.8 is io decreased to 89.0 $. When compared with trial 3, the experimental 5 shows the effect of an increase in curing temperature for additional 9.3 ° C (15 ⁰ F) (i.e. from 232.2 ⁰ O (450 ⁰ P) 246.1 ⁰ G ⁽⁰ 475 S ¹ )), while the curing time increases from 1.25 to 1.5 hours. In this attempt, the percent removal of soiling is decreased from 89 io to approximately $ 55. Based on these results, each of the soiling was assigned an arbitrary value for the degree of difficulty. These levels of difficulty are listed in Table V below. The level of difficulty is defined by the following equation:

10,000 degree of difficulty =

io removal of the contamination with 3 io NaOH (6 hours)

TABLE V

Difficulty levels of standard soils used in the experimental program

Attempt no. 1 2 3 4th 5 Curing time
(Hours.) 1.0 1.25 1.25 2.0 1.5 Curing temp. ⁰ C ( ⁰ P) 218.3
(425) 232.2
(450) 237.8
(460) 232.2
(450) 246.1
(475) Difficulty
Degree 100 105 112.5 143 167 - 14 - •

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These contaminants with varying degrees of difficulty in removing prepared to erläu- the effectiveness of the new furnace inventive ^detergents: tern and they were comparable in the following ^experiments: applies. It should be noted that the soiling with a degree of difficulty of 112.5 occurs most frequently in a domestic oven. Although-the pollution is easier to remove with a difficulty level of 100, while-. ; rend the pollution with a difficulty of; 143 is more difficult to remove than is the case with commonly occurring soiling of the pail, the combination of these standard soiling creates a simple means of measuring the performance of the oven cleaning agents according to the invention.

To accurately measure the performance of these agents, the contaminant range was used so that ^{: the} results do not depend on the contaminant to be removed. In this regard, the investigation of the agent on soiling with a degree of difficulty of 167 was discontinued because difficulties arose in obtaining accurate and reproducible results.

The following experiments illustrate the unexpected effectiveness of the oven cleaning agents according to the invention, the . consist of a low concentration alkali metal hydroxide and an alkanolamine in aqueous solution.

■ Table VI explains the decrease in cleaning when the · ■ Determination of the standard soiling used 5% concentration of caustic alkali is reduced to $ 2.

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TABLE VI

Effect of reducing the concentration of NaOH on removal of soiling in the case of standard soiling

I. Attempt no. 1 2 3 105
2 5 6 7 8th cn
O
CD
OO λ
ON
I. Standard ver
pollution
Focus on
Caustic alkali (NaOH,
Weight %) 100
3 100
2 105
3 79.0 112.5
3 112.5 113
2 3 113
2 0997 Removal of
Pollution {%) 99.6 98.1 89.0 79.0 70.0 23.0

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Table VII below illustrates the unexpected advantages obtained with the oven cleaning agents according to the invention. Referring to the values for -2% and 3 % alkali alone listed in Table VI above, it can be shown that the addition of a small amount of alkanolamine increases the detergency of these agents to a level equal to or greater than that of Agents that contain high percentages of caustic alkali.

TABLE VII

Effect of adding 5% monoethanolamine to a composition containing 2 % NaOH in removing standard soils

I attempt no.

Standard pollution 100 105 112.5 143

Contamination Removal {%) 99.7 96.6 96.2 88.0

It is evident that for any standard soiling, oven cleaners containing 2 % NaOH are not only more effective due to the addition of 5 % alkanolamine, but that these agents are unexpectedly more effective than agents containing .3 % NaOH.

This unexpected effectiveness of the oven cleaning agents according to the invention is further illustrated by the following Tables VIII and IX.

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TABLE VIII

Effect of adding small amounts of monoethanolamine to agents containing NaOH, in the case of pollution removal with standard compression = 100

Experiment No. 12 3 4 56

Sodium hydroxide (wt .-%), monoethanolamine (wt -.%) Soil removal {%)

0 , 5 0 , 5 1 , 0 1 , 9 2 2 , 7 0 1 0 1 0 5 5 , 6 81 , 0 82 89 98.1 99

CTI CD CD

TABLE IX

° co effect of adding small amounts of monoethanolamine to means which corresponds NaOH ⁴⁰ hold, in soil removal at standard soiling = 105

Attempt no.

Sodium hydroxide (wt. % ■) Monoethanolamine (wt. %) Soiling removal (%)

1 2 , 25 3 6th 2 > 25 5 , 25 6th 7th , 35 K5 , 0, 0 , 25 Oil 2 2 2 80 , 0 2 , 0 2.35 2 , 6 0 0 -.5 0 0 1 OJ 79.0 ' 69 96, 99 87.0 95

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j As can be seen from Tables VIII and IX above, the J Addition of a small amount of an alkanolamine to a large extent to the cleaning power of the oven cleaner according to the invention medium at. This is surprising in two ways. As I, for example, in Table VIII, Runs Nos. 1 and 2, and ; Table IX, Runs Nos. 4 to 7, shows the addition of a small amount of an alkanolamine results in low concentration ions of an alkali metal hydroxide lead to a significant ! would take in the removal of dirt. Although means that

Containing caustic alkali alone, which cleans the easier to clean] standard soiling 100 and 105 very well, is used ! the addition of a relatively small amount of an alkanolamine, in addition, improves soil removal performance to increase.

^: Soiling plates (with a degree of soiling of the 112.5 degree of difficulty), which for 1 1/4 hours at 237.8 ° C (460 ⁰ F)

; had been cured, were 6 hours. Long with the invention Oven cleaners that have different concentrations

ι had sodium hydroxide and alkanolamine, brought into contact. These tests were done to determine

¹ whether alkanolamines have a significant impact on cleaning. ability of oven cleaning agents with-low concentration of caustic alkali, the 0.5 to 4.0 % alkali metal hydroxide

■ contain, exercise. ·

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TABLE X

Effect in removing dirt when using agents with
varying concentrations of NaOH and monoethanolamine

I.
fV> Attempt no. 1 5 2 3 4th 5 6th 0 7th 8th 5 O O
I. NaOH concentration (wt. %) O, 0.5 1.0 1.0 1.0 1, 1.0 1, Monoethanolamine concentration
(% By weight ) 15th 0 20th 0 5 9 10 8th 20th 0 0 Contamination Removal (%) 42, 90.0 4.0 58.0 85.0 92, 96.1 46, 50982; Attempt no. 9 5 10 11 . 12th 13th 14th 6th 15th 16 0 + ^ -
O NaOH concentration (wt. %) 1, 2.0 2.0 2.0 2.0 2, 2.6 3, λ co
co Monoethanolamine concentration
(% By weight ) 5 0 0 1 2 5 0 0 1 .0 0 Ul
UI Contamination Removal {%) 76 79.0 78.0 97.0 96.2 88 93.9 89 Attempt no. 17th 0 18th 19th 20th 21 22nd 0 23 24 0 NaOH concentration (wt. %) 3, • 3.5 3.5 4.0 4.0 4.0 Monoethanolamine concentration
(% By weight ) 1 9 O- 5 0 0 2 5 5 10 7th Contamination Removal {%)
• 95 98.4 99.8 97.1 98.9 99 99.5 99

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The results of these experiments show the interaction of alkanolamine and alkali metal hydroxide. Even with just example 1 wt .-% NaOH is obtained by adding 10 wt .- ^ Monoethanolamine achieved soil removal greater than the soil removal achieved with 3 wt.% NaOH achieved alone (see experiments 6 and 16). It is also significant that those oven cleaning agents that additionally contain an alkanolamine in addition to the alkali metal hydroxide, compared to the agents that contain an alkali metal hydroxide Contained alone, at any caustic alkali concentration of 0.5-4.0 wt% for superior soil removal to lead.

It is not intended that the present invention be supported by any particular theory such as why the addition of an alkanolamine to a composition having a low concentration of caustic alkali is an oven. ι creates cleaning agent that is just as effective as ' ■ agents that have high caustic alkali content are limited, but the following discussion may be relevant. "Caustic alkali attacks furnace contamination from the surface" and gradually dissolves it without penetrating through the contamination. On the other hand, alkanolamines react of-; obviously very different from caustic alkalis. The alkanolamine penetrates the soil, likely attacking the bond between the soil and the j surface underneath, so that the soil is lifted off the furnace surface. While caustic alkali alone is effective at high concentrations to remove common household stains in a reasonable amount of time, the particular combination of an alkanolamine and caustic alkali in low concentration is superior in stain removal since this latter oven cleaner can penetrate the stain to lift the contamination from the furnace surface and the

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Caustic alkali attack can allow the pollution from their lower surface. This leads to its synergistic interaction between the caustic alkali and the alkanolamine, so that a high concentration of caustic alkali is not required. To demonstrate that numerous other alkanolamines are as effective as the monoethanolamine described above, oven cleaners containing other alkanolamines as listed in Tables XI and XII below and 1.5% sodium hydroxide or 2.0 % sodium hydroxide were used in the 112.5 standard pollution, tested. In the experiments below, the names of the alkanolamines are abbreviated as follows:

Monoethanolamine

Triethanolamine

Monoisopropanolamine N-methylethanolamine Aminoethylethanolamine diglycolamine

Diisopropanolamine triisopropanolamine isopropanolamine

N, N-diethylethanolamine dimethylethanolamine N, N-diisopropylethanolamine Diethanolamine

N-methyldiethylethanolamine N-ethyl diethanolamine

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MEA TEA MIPA N-MEA AEEA DiGA DiIPA TrilPA IPA DiEEA DiMEA DiIPEA DiEA MDiEA EDiEA

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TABLE XI

I.
ι ο • contains hydroxide, in the Removal of a 112 3 4th , 5 standard pollution • 7th 8th I. Attempt no. 1 2 MIPA N-MEA 5 6 TriIPA IPA Alkanolamine - -AEEA 6.15 6.15 DiGA DiIPA 15.66 12.41 Alkanolamine (wt .- $) - 8.52 84.89 90.89 8.6 10.8 93.67 90.22 οι
CD
CO Pollution removal
distance ($) 79.0 96.78 94.22 89.22 OO
K) 11 12th CD Attempt no. 9 10 MDiEA EDiEA 13th CO
to Alkanolamine DiMEA DiEEA 9.75 10.91 DiIPEA -J Alkanolamine (wt. %) 7.3 9.64 59.0 94.0 10.90 Pollution ent
distance (fo) 76.9 96.9 98.8 S.
I.
r ~ ζ TED

TABLE XII

Effect of adding other alkanolamines to a compound that is $ 1.5 Contains sodium hydroxide in removing a 112.5 standard soil

O CD OO

CD CO CD

ro

Attempt no.

Alkanolamine alkanol amine (G-ew. -

Pollution removal ($)

Attempt no.

Alkanolamine alkanolamine (weight

Contamination Removal (%)

47.22

IPA 12.41

89.0

AT IEA MIPA N-MEA DiGA DiIPA TriIPA 8th, 52 6.15 6.15 8.6 10.8 15.66 88 0 41.0 71.0 62.0 84.0 85.0

10

DiMEA DiEEA 7.3 9.64

79.0

11

MDiEA 9.75

32.0

12th

EDiEA 10.91

50.0

13th

DiIPEA 10.9

95.11

It is evident from Table XI that at a sodium hydroxide content of 2% by weight, all of the alkanolamines tested, with the exception of methylethanolamine and N-methyldiethanolamine, exert a significant improvement in detergency, based on sodium hydroxide alone. Oven cleaning agents which contain 2 wt .- ^ sodium hydroxide and the other alkanolamines in a concentration equal to that of 5 wt .- "/ <> Monoethanolamine clean better than an agent which contains ι 3 wt .- $>. Sodium hydroxide, as in Table IV shown j by reducing the Ätzalkalikonzentration to 1.5 wt .-%,;. as shown in Table XII, the cleaning ability of j means the 1.5% caustic alkali is contained alone, j to 47.22 wt ~ io. This means that at this lower concentration of caustic, the alkanolamines must be more effective to provide a satisfactory level of furnace fouling removal. For example, in Table XI, monoisopropanolamine results in good fouling removal compared to the mean which is 2 wt% caustic contains alone, but the composition containing 1.5 wt% caustic alkali and monoisopropanolamine does not increase percent soil removal compared to that of 1.5 wt% caustic alkali alone.

If this oven cleaning agent is used for soiling with a greater degree of difficulty, for example the 143 Standard pollution will be examined, the influence of the addition of an alkanolamine on the performance even more significant. As in Table XIII below

j shown were oven cleaners that contain various concentrations of sodium hydroxide and monoethanolamine were tested on the 143 standard soiling.

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• Original inspected

TABLE XIII

Effect of the agents made from sodium hydroxide and monoethanolamine in the
Removal of a 143 standard pollution

Attempt. No.

1

'10 11

Sodium hydroxide (wt%)

Monoethanolamine

Soiling [£ removal ($ £)

σ \

3.5 3.7 3.7 3.7 4.0 4.0

10

2.8 23.0 88.0 83.0 70.0 80.0 78.0 84.3 96.0 97.1 99.3

It can be seen from Table XIII above that even when tested against this more difficult soiling, the soil removal is significantly increased by adding a small amount of monoethanolamine (see Experiments Nos. 2 and 3 and 7 and 9). This also applies to the other alkanolamines previously examined, as shown in Table XIV below. In this series of tests, agents containing 3.7 % sodium hydroxide and the other alkanolamines were used on the 143 standard soiling.

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TABLE XIV

Effect of the addition of alkanolamines and 3.7 " sodium hydroxide" in removing a standard soiling

Attempt no.

I.
co Alkanolamine Alkanolamine
(Wt .- ^) cn! ¹ Pollution ent
distance (fo) σ
CD
OO
K) Attempt no. 60 / co Alkanolamine Alkanolamine
(Wt .- ^) Pollution ent
distance (fo)

AEEA MIPA N-MEA DiGA DiIPA TrilPA IPA 8.52 6.15 6.15 8.60 10.8 '15.66 12.41 78.0 98.9 97.1 98.0 82.0 95.4 89.4 97.1

10

13th

DiMEA DiEEA MDiEA EDiEA DiIPEA

7.3 9.64 9.75 10.91 10.9 96.7 94.7. 90.7 90.9 '■ 99.3

«Λ Μ / 15 576

When comparing the oven cleaner, the $ 3.7 caustic alkali

; contains alone and that $ 78> - the 143 standard pollution

j removed (see Table XIII, Experiment No. 7), with the furnace

! detergents, the 3,7 ^ caustic alkali and an alkanolamine

j (see Table XIII, experiments nos. 8 and 9)

! a significant improvement in cleaning with agents

¹ found that the alkali metal hydroxide / alkanolamine

i combination included.

TABLE XV

Effect of adding MEA to a agent which contains 2.09 i ° lithium hydroxide, in the removal of a standard pollution 112.5

Attempt no. ■ 1 2 Monoethanolamine
(Wt .- ^ __ '- 5 Pollution ent
distance (fo) 83.0 98.4

^! Since furnace cleaning agents are known from the prior art, j containing a caustic alkali and triethanolamine, supply ^were: search carried out at the different standard stains with rejuvenation different concentrations of both sodium hydroxide and I triethanolamine to the effectiveness of this specially-J len alkanolamines at an oven cleaning agent with a low content of caustic alkali.

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TABLE XVI

Comparison of agents that contain TEA with agents that contain MEA, in percent dirt removal

Attempt no.

Standard pollution Sodium hydroxide (wt. -F> ) Alkanolamine Alkanolamine (wt .- ^) Contamination removal (fo)

Attempt no.

Standard Soiling Sodium Hydroxide (wt. -Fo) Alkanolamine Alkanolamine (wt .- ^) Soiling Removal (fo)

Attempt no.

Standard pollution Sodium hydroxide (wt .- ^) Alkanolamine Alkanolamine (wt. 50 pollution removal (f>)

1 12.5 1 12.5 1 12.5 1 12.5 1 12.5 112.5 1 12.5 1 O 0.5 0.5 0.5 1.5 1.5 1.5 2 8th MEA MEA TEA - MEA TEA - 15th 20th 15th - 5 12.21 - 42.0 90.0 41.7 46.0 76.0 16.0 79.0 8th 9 ' 10 11 12th 13th 14th KJ 1 12.5 1 12.5 1 12.5 1 12.5 1 12.5 112.5 1 12.5 2 2 3 3 3 3.5 3.5 cn ^ -
--3 vn MEA TEA - MEA TEA - MEA vn
CO -o 5 12.21 - 1 12.21 - 5 KJ ^m 92.1 72.3 89.0 95.9 86.0 98.4 99.8 15th 16 17th 18th 19th 20th 21 1 12.5 1 43 1 43 1 43 1 43 143 1 43 3.5 3.7. 3.7 3.7 4th 4th 4th TEA - MEA TEA - MEA TEA 12.21 - 5 12.21 - 5 12.2 93.1 78.0 96.0 95.0 97.1 99.5 92,

^M / ¹ 5

: From the above Table XVI it is evident that triethanol

! amine the detergency of agents that are 0.5 i ° "to $ 4.0

■ Contains caustic alkali, not increased. In addition, Tri-

i ethanolamine has a detrimental effect on the

: find 6, 9, 12, 15 and 21 investigated agents; this will

¹ evident by the fact that this means to a

'' lead to less pollution removal than the means

; which contain caustic alkali alone.

To further explain the oven cleaning system according to the invention

: medium, the values listed in Table XVII below are used

^: led funds.

TABEL XVII i (.0) (D) ' Weight-5 75.63 83.40 Example no. (A) (B) 2.41 2.50 Water (deionized) 81.00 76.14 3.85 4.00 Bentonite 2.43 2.43 9.65 5.00 50 $ aqueous NaOH 3.93 3.97 0.87 0.90 Monoethanolamine 4.86 9.72 0.96 1.00 lauryl alcohol 0.87 0.87 0.19 0.20 Coconut oil fatty acid 0.97 0.97 6.44 3.00 i perfume 0.19 0.19 ^: Propellant
i 5.75 5.75

Examples A and B in Table XVII above are preferred embodiments of the invention.

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Claims (1)

Claims j (l) oven cleaning agent, consisting of j (a) about 0.5 to about 4.0 weight percent based on the j Total weight of the agent, an alkali metal hydroxide; (b) about 1.0 to about 20.0 weight percent based on the
Total weight of the agent, an alkanolamine, selected
among monoethanolamine, monoisopropanolamine, N-methylethanolamine, aminoethylethanolamine, diglycolamine, diisopropanolamine, triisopropanolamine, isopropanolamine, N, N-diethylethanolamine, dimethylethanolamine, N ', N ~ diisopropylethanolamine,
Diethanolamine ,, N-Methyldiäthanolamin and N-Äthyldiäthanol- ι amine; and ' (c) up to about 98.5 wt% water. ; 2. Oven cleaning agent according to claim 1, characterized in that that it : (a) from about 1.5 to about 3.7 weight percent, based on the total weight of the composition, of an alkali metal hydroxide; '■ ι I' j (b) about 3.0 to about 15.0 weight percent based on the j Total weight of the agent, an alkanolamine according to claim 1; and . (c) contains up to about 95.5 weight percent water. - 32 509824/0997 M / 15 576 3. Means according to claims 1 and 2, characterized in that that the alkali metal hydroxide is selected from sodium hydroxide, potassium hydroxide and lithium hydroxide. 4. Means according to Claims 1 and 2, characterized in that the alkanolamine is selected from monoethanolamine, Aminoethylethanolamine and diglycolamine. 5. Agent according to Claims 1 and 2, characterized in that the hydroxide is sodium hydroxide and the alkanolamine Is monoethanolamine. 6. Agent according to claims 1 and 2, characterized in that the hydroxide is sodium hydroxide and the alkanolamine Aminoethylethanolamine is. j 7. Agent according to claims 1 and 2, characterized in that the hydroxide is sodium hydroxide and the alkanolamine I. Is diglycolamine. j 8. Agent according to one of claims 1 to 7, characterized in that that it also contains a thickener. 9. Means according to claim 8, characterized in that the thickener is bentonite. 10. Agent according to one of claims 1 to 9, characterized in that that it continues to be a solubility-increasing Contains funds. - 33 50 9 824/0 997 M / 15 576 11. Composition according to claim 10, characterized in that the solubility-increasing agent is a coconut oil fatty acid soap or is lauryl alcohol. 12. Means according to one of claims 1 to 11, characterized | characterized in that there is still sufficient propellant to pressurize the system and dispense as Contains aerosol. 13. Means according to claim 12, characterized in that that the propellant is isobutane-n-butane. 14. A method for the production of furnace cleaning agents, characterized in that about 0.5 to about 4.0 wt -.% An alkali metal hydroxide and about 1.0 to about 20.0 wt .-% of an alkanolamines selected from Monoathanolamin, aminoethylethanolamine , Monoisopropanolamine, Ν, Ν-diethylethanolamine, N-methylethanolamine, diglycolamine, diisopropanolamine, triisopropanolamine, isopropanolamine, whore thylethanolamine, N, N-diisopropylethanolamine, diethanolamine, N-methyldiethanolamine and N-ethyl mixed with water diethanolamine to about 98.5% . 15. The method "according to claim 14, characterized in that about 1.5 to about 3.7 wt .-% of an alkali metal hydroxide and about 3 to about 15 wt .-% of an alkanol, amine with up to about 95, 5 % water mixed. - 34 50982 4/0 997 M / 15 576 i _r 16. The method according to claims 14 and 15, characterized in that the alkali metal hydroxide, the alkanolamine and water in an aerosol container, then add sufficient propellant to the system pressurized and to enable its delivery as an aerosol '. ■ 17. A method for cleaning baked-on organic deposits from an oven surface, characterized in that j net, that a can 1 .lagerungen act on the waste 'to 13 during a certain time an oven cleaner according to the arrival j sayings. - 35 - 509824/0997