US3094373A - Tester for laundry process and laundry process employing the same - Google Patents

Description

June 18, 1963 L. F. LUECHAUER 3,094,373-

TESTER FOR LAUNDRY PROCESS AND LAUNDRY PROCESS EMPLOYING THE SAME Filed Dec 4, 1961 Louis F. UECHA UER LINVENTOR. W

ATTORNEYS United States Patent 3,094,373 TESTER FOR LAUNDRY PROCESS AND LAUNDRY PROCESS EMPLOYING THE SAME Louis F. Luechauer, P.O. Box 54, Sugarhouse Station, Salt Lake City, Utah Filed Dec. 4, 1961, Ser- No. 156,753 17 Claims. (Cl. 8-137) This invention relates to means for determining the physico-chemical and chemical parameters which control the process of laundering and to laundering process employing such means.

It is an object of this invention to provide the laundryman with means and procedures to determine the conditions existing in the various steps of his washing operation, in order that he may control the laundry process to reach his objective by fixing the parameters of the laundering process which control the rate and intensity of the chemical and physico-chemical changes occurring in the laundering process.

The laundering process in general involves, in various combinations, a sudsing step, wherein the wash is subjected at an elevated temperature to an alkaline water dispersion of a surfactant such as a detergent, which may be ordinary fatty acid soap or a synthetic detergent; it is then followed by a rinse step and, depending on the nature of the soiled wash, it may be subjected to a souring-olf step by treatment with a solution at an acid pH. It may, however, be subjected to a bleaching step prior to the souring step.

The parameters which affect the laundering process are alkali concentration and temperature and time in the sudsing step, taken in relation to the amount of soil in the wash, the effectiveness of the rinse steps, the alkalinity and bleach concentration, and the time and temperature in the bleach step, and the efiectiveness of the souring step.

It is an object of my invention to provide a testing means and testing procedure whereby the magnitude and effectiveness of the aforesaid parameters may be determined, and the laundering process controlled to produce the most economical washing operation.

The testers of my invention consist of yarn or cloth dyed with dyes, and paper colored by pigments, which undergo color changes which are indicative of the laundering parameters, and testers which are indicative of the duration of the laundering steps or of the degree of mechanical agitation.

It is an object of my invention to provide a tester which will permit the laundryman to determine if the operation parameters in the various steps have been properly adjusted to the service which they are to perform in the laundering operation and to isolate the parameters which are improper in the various steps of the laundering operation. For this purpose, it is an object of my invention to provide a tester comprised of a number of detectors formed of dyed textile materials, which may be cloth or yarn dyed with dyes which, by their color changes, indicate the relative intensity of the factors of concentration of the chemicals and the time and temperature employed in the various steps and the eificiency of the various steps of the process.

Other detectors may be employed by using sensitive pigments for the purposes to the described below.

By using these detectors in combination, the relative influence of the various process parameters which combine to produce the laundering elfects in the various stages of the process may be segregated from each other.

The laundry industry, for many years, was devoted primarily to the laundering of household items sent in by customers. The advent of home washers in almost every ice household shifted the emphasis to rental plants who supply their own linens to home, hotels, restaurants, beauty shops, industrial plants, and the like. Customers who rent linen often abuse it badly. This poses a two-pronged problem for the rental operator. He must use formulas that are sufiiciently severe to remove the stains, and at the same time avoid undue damage to the linen which he owns. Linen replacement expense often averages onefourth of the total income, and demands careful attention in achieving adequate laundering Without undue damage to the linen.

The testers of my invention are designed to assist the laundry to achieve its objectives with economy.

THE LAUNDERING PROCESS The washing formulas recommended by the ALL. (American Institute of Laundering) for laundering of household and personal linen, included a series of sudsing operations, usually involving alkali and :soap followed by a bleaching step, then four or five rinses. Starting temperatures were usually low (in the range), and subsequent sudsings seldom exceeded The linen supply operator found it necessary to use higher temperatures; and instead of using three of four ten minute. sudsing steps, one longer sudsing at higher temperatures along with a fairly high concentration of alkali proved to be much more desirable. As a rule, two to four flushing steps were required to remove sufficient amounts of loose soil for adequate bleaching intensity.

Linen supply operators found it advantageous to classify the twenty or so different items which they normally furnished into the categories of light, medium and heavy soil. They also found that it was not feasible to achieve 100% stain removal in even heavy soil or severe washing formulas. Hence, stained items are accumulated and are re-w-ashed with formulas commonly referred to as a stain treat formula.

Laundrymen also use such terms as mild, normal and severe to describe alkaline and/or bleaching intensities.

THE NATURE OF SOILS ENCOUNTERED IN LAUNDRY OPERATIONS The following are given not as a limitation of my invention or of the practice followed in laundries, but for the purpose of orientation and explanation for a better understanding of my invention.

Light S0il.Lightly soiled items in a linen supply plant are those which are neither badly stained nor contain appreciable quantities of loose soil. Sheets used by hotels are considered light soil. In many cases towels from barber shops fall into this same category. Sometimes it is unnecessary to use bleach to achieve adequate whiteness. Weight of the soiling material in items in this classification is negligible; for example, approximately one-half pound of dry soil (0.2%) per 300-pound load may be taken as typical.

Medium SoiL-Medium soil in a linen supply plant usually consists of waitress dresses, towels from beauty shops, andin some cases-napkins from restaurants. Weight of the soiling material in items in this classification is greater than in the light soil, above. This classification will also contain some stains which require stronger cleaning solutions; for example, approximately five pounds of dry soil (2.0%) per SOD-pound load may be taken as typical.

Heavy Soil.ltems falling into this category not only contain stains, but appreciable amounts of loose soil which must be flushed or rinsed out of the washing machine in order to avoid gray work. Items in this classification would be aprons from butcher shops; towels from restaurants; and swipes that are used for clean-up purposes. Weight of the soiling material in this category will be,

for example, approximately 30 pounds of dry soil (10.0%) per 300-pound load, as a typical figure.

Stained or Re-Wash Loads.Formulas used in this category must be severe enough to remove the stains that it was not feasible to remove in the original laundering by any of the formulas shown above. There is substantially no loose soil present, and treatments suitable for handling these items would be aimed primarily at removing stubborn stains. One of the most common stubborn stains occurring in rental plants is mildew.

Industrial Soil.-Some laundries specialize in handling industrial items such as towels and coveralls from garages and industrial plants. These items contain oily soil rather than fatty soil; and both formulas and supplies used on them are quite different from that of the ordinary rental plant. Weight of the soiling material in this classification is far greater than in any other; for example, approximately 100 pounds dry soil (30.0%) per 300-pound load may be taken as typical. At this point it may be best to understand the terms insufficient, normal and excessive, as employed in laundry practice.

Any quantity less than that normally used on light soil is considered insufficient. The concentrations used on medium soil are considered excessive for light soil.

For example, alkali concentrations for light soil and medium soil may be typically as follows:

Table 1 7 Light soil, Medium percent soil. percent Tnsnfficient 0.05 0. 1 Normal O. 0. 2 Excessive 0. 0. 3

These figures are intended for orientation and explanatory purposes, and not as limitations of the percentage and ranges which may be encountered in laundry operations.

TYPICAL LAUNDERING FORMULAS Numerous alkalies may be used by commercial laundries. Sodium or-thosilicate or its equivalent is most common. There are extreme variations in the concentrations used by various plants. Also, pH values change during a sudsing operation of a washing formula. The quantity of fatty soil which may be present has a decided effect upon them. For example, variations in alkaline concen- (nations (and changes in pH values most often occurring in commercial laundry practice are shown below:

The above percentages or pH ranges are those most commonly employed for these services in commercial laundries, although variations therefrom are also, but less frequently, employed. These figures, therefore, are included for orientation and explanatory purposes and not as a limitation of the percentages and ranges which may be encountered in laundry operations.

Many laundries use mixtures of polyphosphates and alkalies. Mixtures that contain phosphates are considered mild alkalies. Anhydrous metasilicate is also considered a mild alkali. Orthosilicate, on the other hand, is considered a strong alkali. Few plants use caustic soda unless it is buffered with soda ash, phosphate, etc. In the discussion which follows, the following table will help:

Polyphosphates are considered non-alkaline.

Metasilicate is considered a mild alkali.

Orthosilicate is considered the normal alkali.

Caustic soda is considered a strong alkali.

The table below shows the time and temperatures often used on suds and bleach baths. As a rule, flushes are required to remove loosened soil prior to the bleach bath. Flushes are usually three minutes in duration, and the number used may vary from one to five or six.

Table III Temperature (deg) Time (min) Type of formula Suds Bleach Suds Bleach Washing temperatures in the 200 to 210 range are considered excessive by most plants. Many plants use washing temperatures as low as 145 to in washing light soil. Sudsing temperatures below 145 are generally considered inadequate for either soil removal or sanitary aspects of laundering.

Formula times shown above are those considered average in most plants, but times of treatment will depend on objectives desired and the other parameters of the laundering process, as described above.

Formula times may be varied also due to the type or kind of washer used. Those shown above are those most often encountered with open pocket washers. This type of washer is one without horizontal partitions, and with a rotational speed usually or 21 revolutions per minute.

The bleach concentration data most often encountered, as shown below, is the initial concentration in the washer. During an eight minute bleach bath on many formulas the final concentration is often in the range of 10 to 20 parts per million. The pH of the bleach bath changes during a bleaching step due to the release of hypochloric acid. The range of values generally found is 9.8 to 10.5. Low pH bleaching, as used by the average laundryman, would indicate values near pH 7. High pH bleaching in most plants would be considered values in the neighborhood of 11.5.

bath, percent None or 0.002 0. 005 0. 01 0. 1 0. 01

Ham-n... 000. 0 cacao-1H0 Industrial Throughout this specification, except as separately stated, bleach is understood to be hypochlorite, usually added in the form of sodium hypochlorite.

As in the previous tables, these percentages and pH values are those most commonly employed in laundry operations, but they will vary depending on the objectives desired and other parameters, as described above in connection with the other tables.

Illustrative of the formulas employed in laundering, the following are given as examples of typical formulas for the uses indicated. It will be understood that deviations and alternative formulas may be employed, and the formulas given are for illustration and explanatory purposes. In the following Tables V-VIII, percentages are given as percent by weight.

5 Table V NO. 1FORMULA FOR LIGHT SOIL [Standard size 42 x 84 open pocket washer] Water Temp,

Time,

Operation level, minutes inches (1a) Flush, bloody loads 6-8 120 3 (1) Flush 6-8 Hot 3 (2) Alkali suds: Orthosilicate cone.

0.1%, soap concentration 0.02%. 3 175 10 (3) Rinse 12 1 Hot 3 (4) Rinse 12 130 3 (5) Rinse 12 120 3 (6) Rinse 12 Cold 3 (7) Sour, ammonium silicofluoride cone. 0.02% Cold 1 Temperatures are not critical, usually 160.

Table VI NO. 2-FORMULA FOR MEDIUM SOIL [Standard size 42 x 84 open pocket washer] Water Temp, Time, Operation level, F. minutes inches (1a) Flush, bloody loads 6-8 120 3 (1) Flush 6-8 Hot 3 (2) Alkali Suds: Orthosilicate cone.

0.2%, soap concentration 0.06%- 3 185 15 (3) Flush 12 150 3 (4) Flush 12 150 3 (5) Suds bleach: Soap concentration 0.01%, bleach concentration 0.005 X 6 145 8 (6) Rinse 12 145 3 (7) Rlnse 12 130 3 (8) Rinse 12 120 3 (9) Rinse 12 Cold 3 (10) Sour,

cone. 0.02% 6 Cold 5 1 As sodium hypochlorite.

Table VII NO. 3-FORMULA FOR HEAVY SOIL [Standard size 42 x 84 open pocket Washer] Water Temp, Time, Operation level, F. minutes inches (1) Flush (Water only) 12 Hot 3 (2) Alkali Suds: Orthosillcate conc.

0.4%, soap concentration 0.2%"- 3 195 12 Hot 3 12 Hot 3 12 150 3 (6) Flush, optional 12 150 3 (7) Suds Bleach: Soap concentration 0.1%, bleach concentration 0.01%L 6 145 8 (8) Rinse 12 145 3 (9) Rinse 12 130 3 (10) Rinse 12 120 3 (11) Rinse 12 Cold 3 (l2) Sour, ammonium sihcofluoride cone. 0.02% 6 Cold 5 1 As sodium hypochlorite.

Table VIII NO. 4FORMULA FOR STAIN TREATING [Standard size 42 x 84 open pocket washer] Water Temp, Time, Operation level, 1*. minutes inches (1) Flush 6-8 Hot 3 (2) Rustremovahoxalicacid conc.0.2%. 3 165 3 (3) Flush 12 Hot 8 (4) Flush 12 Hot 3 (5) Alkali break: Orthosilicate cone. 0.4%, tetrasodiumpyrophosphate (TSPP) conc. 0.1% 3 195 10 (6) Flush 12 150 3 (7) Flush 12 150 3 (8) Suds bleach: Soap concentration 0.1%, bleach concentration 0.1%. 6 145 (9) Rinse 12 145 3 (10) Rinse 12 140 3 (11) Rinse (remove bleach), sodium thiosuliatc concentration 0.02%-. 12 120 5 (12) Rinse 12 Cold 3 .(13) Sour, ammonium silicofluoride cone. 0.02% 6 Cold 5 1 As hypochlorite.

THE PROBLEM SOLVED BY MY INVENTION The values referred to above are dependent upon the objective of the laundryman. If his objective is a minimum damage to the fabric, he will, for various types of items laundered, employ for the criteria of normal those conditions which give a minimum of washed laundry which needs rcwashing with a minimum amount of damage to the laundry. If his objective is to obtain minimum of items that must be rewashed, he may use those conditions which produce such minimum without regard to the damage resulting from such conditions. If his objective is to minimize the damage Without regard to the number of items which will require rewashing, he will use those conditions which will give him the minimum damage and suffer the consequences of the excessive number of items which will require rewashing.

It is to be recognized that laundering, i.e., washing procedures and bleaching procedures, are all rate processes and also statistical processes. What is involved are a large number of foci of soil on fabrics, and the process of soil removal and of bleaching is a heterogeneous physico-che-mical reaction which, in the sudsing operation, depends upon the magnitude of those foci, the concentration of alkali and detergent, temperature, time, and the number of such sudsing steps employed.

The bleaching operation is also a rate process and depends on the quantity and character of the soil foci remaining after the sudsing steps, the concentration and quantity of bleaching agent, the pH of the bleaching bath, the temperature of the bleaching bath, and the duration of the bleaching step.

The quantity of soil foci and the pH of the bleaching bath are dependent on the antecedent conditions in the sudsing steps. Therefore, the laundryman may adjust any one or more of the factors entering into the laundry formula to reach the objective he sets for his operation, provided he knows what he is doing.

The laundry operation may be said to be eificiently operated if the product is produced clean with a. damage to fabric and with a mini-mum use of chemicals at minimum temperatures and times.

The laundering operation as stated above is a rate process, and the chemical and physico-chemical reactions involved depend not only on the times and temperatures but also on the character of the mechanical agitation and the ratio of chemicals to soil and to fabric present in the various steps and concentrations and quantities of chemicals.

Thus, insuflicicnt alkalinity or insuflicient time in the sudsing operation may result in insuflicient removal of soil, so that an excessive amount of soil is present during the bleaching step.

An excessive alkalinity or an excessive temperature or an excessive time in the alkaline bath may cause damage to the cloth, particularly if it is alkali sensitive.

In like manner, an excessive agitation or excessive time during agitation in the sudsing bath may cause physical damage duringthe sudsing and rinsing.

An insufficient bleaching results in an excessive amount of stained fabric that must be rewashed. This insufficiency may be caused either by insufficient soil removal in the sudsing step or insufficient amount of bleach in the bleaching step, or insufficient temperature, time or agitation in the bleaching step.

An excessive bleach results in damage to fabric, and this may be caused by an excessive ratio of bleach to soil, or bleach to fabric, i.e., concentration and amount of bleach chemicals, excessive alkalinity, excessive tempcrature, and undue duration of bleaching step, and inadequate agitation.

The purpose of the souring operation is to destroy the bleaching agent when it is used, or the residual alkalinity when no bleaching step is used. If inadequate rinsing or souring occurs, the bleach will persist through ISCC-NBS numbers.

the souring step and be retained by the cloth, and may continue to act after washing and cause damage to the cloth. This occurs when the pH of the sour bath is insufliciently low.

THE DETECTORS OF MY INVENTION Since the detector samples and the test procedure depend on color and color changes in the dyed textile materials and the inked sheet material, the following will be explanatory of the term used in identifying the colors and dyes.

Dyes are classified by a color index, as is well known to dye chemists. This color index is entitled Colour Index, published by Society of Dyers and Colourists, Manchester, England, 2nd adition (1956). This book identifies the composition and characteristics of the dyes, and will be herein referred to for this purpose, and is incorporated into this specification by this reference.

This book classifies the various dyes by a number which is prefixed by the symbol CI. As is shown in the above volume, dyes are classified under a CI number, which number includes various dyes believed to be of similar chemical constitution and which in use will give similar colors and dye properties. It also lists a number of examples of the dyes included in the classification under such CI number and gives their constitutional formulas.

Color may be identified by employing the nomenclature of various systems generally adopted for such'purposes. See I.S.C.C.N.B.S., Method of Designating Colors and a Dictionary of Color Names, National Bureau of Standards Circular 553, U.S. Department of Commerce. This circular describes and correlates various systems by which color is designated. In this specification, where ISCC-NBS colors are designated by reference to ISCC-NBS designations by means of numbers, it is intended to include all colors, however designated, under the ISCC-NBS number specified. These ISCC-NBS designations by numbers will be hereinafter referred to as Since such classification 'in some cases includes two different colors separately designated in any color system included within the ISCC-NBS numbers, and a closer designation is desired, reference will be had to both the ISCC-NBS number as well as to the designation by some other classificaiton. Thus, for example, 145 Medium Green, i.e., rnGl45 (given at page 62 of the above circular) includes various different colors given in the Merz & Paul Dictionary of Color and four colors by the Plochere Color System and various other colors by other classifications, all identified in the circular. Where, however, it is desired to isolated such colors, as, for example, only Plochere Color 1034 is specified, then this excludes all colors not equivalent to the Plochere Color 1034.

It is to be noted in this connection that Plochere Color 1034 may also be designated by other systems, for example, in the Munsell system it would be designated as 6.0G3.8/ 2.5 and the Munsell system will also be used in the following descriptions. Identification of these systerns, which are standard and well known, may be had by reference to the above circular.

In the discussion which follows, colors will be referred to by their Plocher-e number and corresponding Munsell Color. An article by W. E. Knowles Middleton in the Canadian Journal of Research 'F27: 1-21, January 1949, shows how it is possible to cite either or both numbers in defining color changes.

Dyes and pigments used in forming the various detectors employed in forming the tester combinations of my invention have been selected because f their properties in producing dyed textiles and paper and other sheet material, which undergo specific color changes indicative of the parameters previously discussed. While the dyes and inks specified herein are chosen because they have shown properties most preferable in indicating these parameters, it will be understood that other dyes and inks having sim- Dyeing procedures are shown below. Wherever percent is used, it means ratio of the weight of the paste or concentrate used to the pounds of fabric dyed.

Table IX Percentages by weight of dye in the dye bath used was as follows:

Dyes classified in colour index as dye color Detector #1, Bleach green. 01 59,850 5% of paste. Detector #2, Light blue CI 7 6% of paste. Detector #3, Dark blue- OI 73,065 8% of double paste. Detector #4, Pink CI 16,605 1.25% of paste. Detector #6, W001 dye CI 45,100 2.0% of paste. Detector #7, Direct green (Seal below) These pastes are the commercial designations of the dye concentrations used.

The regular reduced jig method was used on the first four dyes shown above. Essentially it was as follows:

Bleached x 80 print cloth was used; hence, preliminary scouring was unnecessary.

The liquor ratio was six to one (6:1). The pastes were reduced with a solution of concentration of 0.02% caustic soda and 0.025% sodium hydrosulfite. The reduced dyestuif was introduced into a bath that contained a concentration of 2% caustic soda and 2.4% hydrosulfite. The fabrics were run in the dyebath for /2 hour at 140 F. The cloth was removed and the cloth rinsed in cold water until the dyes were oxidized.

The fabric dyed CI 16,605 of detector No. 4 was given additional rinsing because it is not treated by the usual soaping off treatment. The other three vat colors were soaped off with 1% perborate and a neutral soap,

starting at and going to a boil. All of the fabrics were dried on a tenter frame.

An acid dyeing was used on the wool fabric of detector No. 6, using CI 45,100. The liquor ratio was 40:1. The dyeing was carried out in a solution of a 20% anhydrous sodium sulfate bath with 4% concentrated sulfuric acid (35 Baum). The starting temperature was One half hour was used to reach a boil. The fabric remained at this temperature for one hour. Normal rinsing procedures were used. No after treatments were given.

The wool fabric itself is a white worsted flannel, style 503-A, that is sold by Testfabrics, Inc., 55 Van Dam Street, New York 13, New York.

The dyeing procedure for the green fabric, detector No. 7, dyed with the dyes as described below, was that common for dyeing with direct cotton dyes. The standard 80 x 80 print cloth was cut and hemmed into 72 inch lengths in order to avoid tangling in a commercial washer. The size of the machine was 36" in diameter and 54" long. Its rotational speed was 21 r.p.m., reversing after each 7 /2 revolutions. The liquor ratio was 30:1; NaCl was used, based on fabric weight. Cross comparisons with lab dyeing gave identical performance to those dyed in the commercial washer on all types of washing formulas, except extremely mild procedures used by the average housewife.

The dye transfer from this fabric to the sack that surrounds it, as is more fully described below, during the average washing formula, can be correlated with the dyeing characteristics of this dyestulf; i.e., regardless of time, temperature and salt content, complete exhaustion of this dyestuif is impossible. Also, only one-fifth of the color goes on to the fabric at 120 F, compared'to 9 an identical concentration at 160 or 190. Hence, by starting the dye bath at low temperature and then raising it with steam, we .achieved uniform dyeing not only from batch to batch, but also over every square inch of fabric.

The concentration of the dye in the dye baths employed is such as to avoid either extremely high concentrations or such low concentrations such that pastel shades are produced.

The following examples of the dye concentration on the fabric dyed with CI 59,850 are given by way of illustration and not as a limitation of my invention.

Where the dye bath is made up with 10% instead of of paste, this produced a fabric that turned black with mild bleaching intensities, and it was difficult to differentiate between mild and normal intensities.

The 5% concentration given above was selected as the optimum in evaluating changes in ordinary light.

Concentrations ranging from 2.5% down to 0.1%, graduated as follows: 2.0%, 1.0%, 0.5%, 0.25% and 0.1%, showed a tendency to lose sensitivity to bleaching intensity when viewed in ordinary light. At a concentration of 0.1% it was necessary to use an ultraviolet light to observe the difference between medium and heavy soil formulas.

The Plochere and Munsell colors of these dyeings ranged as follows:

The effect of dye concentration of the fabric for detector No. 2 was as follows: 6.0% paste yielded the color changes shown previously, and a 2.0% of paste in dyeing gave a tester which became colorless at low pH values instead of yielding a yellow color, as desired, and as will be described below.

Three concentrations were tested with the Dark Blue, CI 73,065, detector No. '3. A solution made up with by weight of double paste produced a fabric which was insensitive to changes in bleaching intensities common to fairly severe heavy so-il formulas. A 6.0% solution, on the other hand, gave color changes that were about the same as those of detector #2. Either of these concentrations could be used. However, the fabric dyed with a dye solution containing 8% by weight of the double paste was selected a the most satisfactory.

When using CI 16,605 dye for detector No. 4, a solution containing 2.5% by weight of the paste did not show the characteristic change to a blue shade, as is described below, as readily as 1.25% when the dyed fabric is viewed in ordinary light.

The reddish purple woolen fabric of detector No. 6 was dyed with 1.0% and 3.0% by weight of the dye paste employing dye CI 45,100. Since almost any commercial laundry formula decolorize this fabric, a 2.0% dyeing was adopted as standard. In testing extremely mild formulas, a fabric dyed with a solution containing 1% by weight of paste would be advantageous.

In forming detector No. 7, a dye solution containing 1.0% by weight of the following dye mixture was completely decolorized by the severe stain removal formula in which both bleaching and alkaline intensities are fairly high. A solution containing 2% by weight of the dye mixture retained enough color to differentiate between heavy soil formulas and those used for stain treatments; hence, it is preferred.

The dye mixture was as follows:

97.20% by weight of CI No. 30,925

2.50% by weight of CI No. 11,020 .05% by weight of CI No. 19,555

In every case the detector, after dyeing, should be air dried, care being taken that it is not heated or ironed after air drying, or excessively tumbled during drying.

For convenience, the detectors 4 to 8 are mounted on a large swatch, edges pinked, of poplin, forming detector 8a. Detectors 1 to 3 may be separately mounted on a piece of fabric or mounted together with 4 to 7 on detector 8a.

FIG. 1 illustrates a tester formed of detectors 1 to 8 mounted on detector 8a.

FIG. 2 is a section taken on line 2-2 of FIG. 1.

FIG. 3 illustrates another tester, to be employed where no bleaching step is employed, and showing the detectors 4 to 8 mounted on detector 8a.

FIG. 4 is a modification of the tester of FIG. 1.

In following portions specific examples of the changes in the detectors are explained. For best results it is desirable to preserve a separate, unused set of detectors and compare the detectors after test with the fresh, unused detectors.

Detector N0. ].-Detector No. 1 is a bleaching intensity indicator, composed of a textile such as a swatch of cotton fabric or a piece of cotton yarn dyed with a dye which changes in color if the bleaching intensity is moderate or excessive. A preferred form is green fabric, as described above, which was dyed by the above procedure with 5% concentration of No. CI 59,850 dye (CI Vat Green 9believed to be dinitroviolanthrene), to give a color equivalent to ISCCNBS No. 145, and prefer-ably a color equivalent to Plochere 1034 or Munsel 6.0G 3.8/2.5.

This green fabric is pinked at the edges and identified as 1, located on the left side of the first (top) row of FIG. 1, mounted in detector So by stitching it to the fabric of detector 8a by a line of stitching In. It will turn black with a concentration of bleach based on liquor volume of 0.01%; and in the presence of normal quantities of soil in the average commercial laundering. More soil or less bleach will cause it to change to darker shades of green, e.g., Plochere 1089-Munsell 2.5G 2.3/0.8, or Plochere 1049-Munsell 4.0BG 25/05. The change is unaffected by the pH of the bleach bath. Neither chlorine in the water supply or from soiled towels. as employed in commercial laundries is of sufliciently high concentrations to cause the fabric to turn black. Chlorine con centrations of 0.1% do not intensify the black color. 1 It may lighten the color, due to the intensity of the bleaching eifect. It becomes evident that additional fabrics are required to measure severe bleaching effects.

There are no color changes in detector #1 which in dicate undesirable bleaching conditions. The objective of every commercial laundry is to achieve stain removal with the minimum bleaching intensity. If satisfactory stain removal can be achieved without causing a change to black, the operator of the laundry would be quite content. If, on the other hand, appreciable quantities of his towels and garments would require a rewash or stain treatment, it would be desirable to purposely alter the formula so as to increase bleaching intensity which would be reflected in a blackening of this detector.

Detector No. 2.-Detector No. 2 is an alkali reaction intensity indicator, composed of a textile such as a swatch of cotton fabric or a piece of cotton yarn .dyed with a dye which changes in color and loses color as the alkalinity of the bleaching bath increases, or the time in the bleach bath increases, or the temperature increases, or the concentration of bleach is increased. It may, for such reason, he said to be an indicator of the product of the effects of alkalinity, time of bleach, temperature of bleach, and bleach chemical concentration. The preferred form is the light blue fabric, as described above, which was dyed by the above procedures with concentration of dye No. CI 74,140 (CI Vat Blue 29-partly sulfonated cobalt phthalocyanine), to give a color equivalent to 11 ISCCNBS No. 169, and preferably a color Plochere 771 or Munsell 6.0B 4.9/9.0.

This light blue fabric, pinked at the edges, is identitied in FIG. 1 as 2 and mounted on the fabric of 8a equivalent to 12 is responsive to total bleaching intensity becomes apparent. This is achieved by using the dark blue fabric CI 173,065, detector 3.

Detector N 0. 3.-Detector No. 3 is a bleaching intensity by a line of stitching 2a. The fabric will lose color as 5 level indicator composed of a textile such as a swatch of the bleaching intensity increases. If the pH of the bleach cotton fabric or a piece of cotton yarn dyed with a dye bath stays above 10.2, a blue shade will result, even which loses color without substantial color change if the though appreciable color loss occurs. If, however, the bleaching intensity is excessive. It is an indicator of the pH drops to 9.2, the resultant color will be green, and minimum level of bleach concentration and also indiwith a pH value of 8.2, a yellow color will be observed. cates the level and temperature of bleach. It may, there- During the average bleach bath in a commercial or fore, be said to be an indicator of the minimum level household washer the color loss is proportional to the of the product of the effects of bleach concentration, time rate at which the bleach is decomposed. Generally, sufand temperature, to indicate the existence of a bleaching ficient alkali is present to maintain a blue shade. If the t, and l also indicate a level of bleach intensity pH. of the bleach bath is deliberately lowered to 6.5, greater than the desired level of bleaching. It is subby the use of la polyphosphate, the light blue fabric will stantially insensitive to alkaline pH, and thus will indichange to a tan color almost instantly, and then the shade cate an excessive degree of bleach resulting from either changes fro yellow to almost white will occur if nffitoo large a concentration of bleach chemical or too high cient bleach is present. Neutral pH bleaching bath ata temperature or excessive time. It thus is a measure tacks the amorphous region of cotton fibres, and thereby 0f t n d effect f bleach COIlCeIltratiOIl, mperarenders them sensitive to subsequent alkaline treatments. ture and time 011 the intensity of bleach attained. Color changes in this light blue fabri thu erve two A preferred form is the dark blue fabric, as described purposes-avoiding too much bleach, and avoiding bleachabove, a y y the above procedure with concentration ing at neutral pH values on regular wash loads. of CI No. 73,065 dye (CI Vat Blue 5; for its constitutional The dyestulf in this fabric is mildly chlorine retenformula, see the Colour Index), to give acolor equivalent tive, if the bleaching intensity is severe; and, in additon, to ISCC-NBS No. 194, and preferably a color equivalent evaluation of the detector is delayed for several days to Plochere 625 or Munsell 8.0PB 2.8/14. or 'a week, on regular loads, there would be a shift in The dark blue fabric, identified in FIG. 1 as 3, is hue from blue to green. On stained loads (where appinked at the edges and mounted on the fabric of detecpreciable quantities of bleach are required, i.e., 0.1% by tor 3a by a line of stitching 3a. It does not lose a noweight), the shift in hue will be from green to tan; and ticeable amount of color when subjected to the average at higher bleaCh concentrations "ihfire W111 commercial or household laundering. When it is necesbe a complfite 1055 of 1010f W anotlPeable weakening sary to re-wash fabrics in order to remove stubborn of the fabnc' In Prdsr to avold shlfi I f an stains, such as mildew, a moderate loss of color occurs. 32 X sggfig gg i i fl gg 3; g ggg n ti 35 In this case pH values do not alter the final shade change. der a fraction of 1% the rinse i g if; (in rewash loads in a commercial laundry, where the quan- 0 0057 t 0 057 f 1 r a p tlty of oxidizable soil is at a minimum, an initial cono o a or examp e, 0.01% is suitable. t f 017 M h t 0 F f 20 t The desirable and undesirable changes in color in this ra lon o 1 0 eac a or i es Will cause sufficient color loss to be readily recognizable. fabric depend on the specific ObJCCtlVC of the washing 40 F formula. For example, bloody stains on butcher aprons or m i einploymg Formula 2 4 Wlth a hqind are best removed with a high pH bleach bath. In this to fabnc who ol at the 18 coPsecutlve Case, the blue color of this detector may decrease in removal treatments a little color w1ll still remain in the tensity, but it does not shift towards green or yellow fabric; Tables XI XIL) h Haw/aver, h mildew stains, the PH of the bleach 425 This fabric is quite useful in relating the relative inb th must b l d, M h l bl h i required at tensity of one stain removal treatment to repetitive norpH val e may 7,0 th t 9,() Th a green color with mal launderings. In some commercial laundries the rathis detector would be desirable, provided that excessive tio is 2031; that it Tfiquires twenty Consecutive regular quantities of bleach were avoided. The need fo a f blaunderings to induce a loss in color that matches that ric that is not affected appreciably by pH values and of one stain removal treatment.

Table XI EXAMPLES OF COLOR CHANGES WHICH OCCUR WITH BLEACHING INTENSITIES WHICH MAY BE ENCOUNTERED IN COMMERCIAL LAUNDRIES Detector N o. 1 Detector N0. 2 Detector No. 3

Plochere Munsell Plochere Munsell Plocherc Munsell a aggre atin 2a..-ei833 2:283:2/315 a as are as at: (3) haillerglzgdglelaigiing, maximum change 1049 4BG 2.5/0.5 772 7B 5.7/9 625 8.0PB 2.8/14 (4) Fzifiglggntiegrileablgagfing, maximum Black 773 7.5B 6.5/8.5 626 8.0PB 3.8/13 (5) Segeg rg e a cgl ng r i a x i r l l1 m change Black 774 8.0B 7.6/7 627 8.0PB 5.6/13 (6) Dls gitggeebggzlilaigibtglgrrizgange indicates Black 776 9.0B 9/3 628 7.5PB 6.4/12

Slightly alkaline bleach Neutral bleach Plochere Munsell Plochere Munsell (7) My); gliillidllgaggfigfelrgggglnum changes Black 1030 6.5G 8.0/3.5 38 5.5Y 8.5/2.5 026 8.0PB 3.8/13

13 The following illustrates the changes in color of the detectors under various bleaching conditions:

Table XII Plochere Munsell Detector #1 (Bleach sensitive green):

Control 1034 6.06 3.8/2.5 Mild bleach.-- 1039 2.5G 2.3/0.8 Severe bleach 1049 4136 2.5/0.5 Black (excessive bleach) None None Detector #2 (bleach sen itive light blue):

Ontrol.. 771 6.013 4.9/9 Mild bleach. 772 7.013 5.7/9 Normal bleach 773 7.5B 6.8/8.5 Severe bleach 774 6.013 7.6/7 Green (slightly alkaline bleach) 1030 6.5-G 8.0/3.5 Yellow (neutral bleach) 38 5.5Y 8.5/2.5 Detector #3 (bleach sensitive dark blue):

ontrol 625 8.0PB 2.8/14 Mild bleach. 626 8.0PB 3.8/13 Normal blea 627 7.5PB 6.4/12 Severe bleach. 628 7.0113 7.5/

Table XIII Plochere Munsell Original color 625 8. OPB 2.8/14 Heavy soil bleaching- 626 8. OPB 3.8/13 Stained load bleachin 627 7. 51 B 6.4/12 Excessive bleaching. 628 7. OPB 7.5/10

Reference should also be made to Table XII in this connection.

In the Plochere system a change in number from 625 to 628 indicates the addition of increasing amounts of white pigment to the original color. With the Munsell system, hue segment of purple blue is described by the first digit. A change from 8.0 to 7.0 is very small. This explains the difference for the Munsell number for the Plochere 6 27 and 628 of Table XIII, as compared with Table XII. The accuracy of the observation that this dye is unaffected by pH values of the bleach bath is further substantiated by the fact that the range of values in the second portion of the Munsell system is regular and normal, i.e., 2.8 to 7.5. This number describes the grayness of the color change. That is, a value of 0.0 is black, 5.0 is gray, and 10.0- is white. The regularity of the group ing in Table XII about 5.0 is apparent. The last number under the slash describes the intensity of the hue, often referred to as chroma or saturation. These numbers range from fractional 0.5 to 20. This makes it possible to be quite explicit in stating desirable and undesirable color losses. Hence, if the change in color for a medium soil formula (see Table X1) is as great as that shown for a heavy soil formula, corrective measures should be initiated. The conditions shown for Plochere No. 6 28 (Tables XI and X11) are highly undesirable for anyregular washing formula, and should be avoided even for stain removal treatments.

These three detectors 1, 2 and 3, when used together in the bleaching step, will indicate whether the bleaching is insufficient, or normal, or excessive. Detector No. 2 Will also indicate whether the pH was either too high, normal, or too low.

If these three indicate insufficient or excessive bleaching, it will not, if the improper conditions arise from other than abnormal pH, reveal this abnormality in the other parameters.

This abnormality is indicated by detectors 4, 5, 6, 7, 8 and 8a, described below.

Detector N0. 4.--Detector No. 4 is a temperature indicator composed of a swatch of cotton cloth or a piece of cotton yarn dyed with a dye which is temperature sensitive, and will indicate whether the temperature is below a determined temperature set as normal for this operation or is above such temperature. It may thus be termed a temperature level indicator. This textile is enclosed in a plastic film formed of a polyamid of a dibasic acid, sold as Nylon Autoclavable film by the Sierra Manufacturing Co., at Sierra Madre, California, and heat sealed to make it impervious to dyes or optical brighteners used in the washing process, although not impervious to water. This sealed package is enclosed in a heavy, unbleached cotton sheathing, to protect the plastic package against mechanical damage. It may be used alone, as shown in FIG. 4, or together with detector No. 5, as shown in FIGS. 1 and 3.

A preferred form is the pink fabric, as described above, dyed by the above procedure with concentration of dye CI No. 16,605 (CI Acid Red or Pink PR l24f0r its constitutional formula, see the Colour Index), to give color equivalent to lSCC-NBS No. 248, and preferably a color equivalent to Plochere 388 or Munsell 8.0RP 5 .5 11.5.

The pink fabric is identified on FIGS. 1 and 2 as 4 and is enclosed in a heat-sealed plastic envelope 14 and enclosed in an overfolded muslin cloth formed into an envelope by lines of stitching 11 and mounted on the fabric of detector 8:: by a line of stitching 12. This fabric is used to evaluate temperature effects. The original fluorescent pink shade is achieved by avoiding the normal high temperature soaping off, i.e., washing with soap, as is described above. However, a fairly high temperature F.) wash must be used to observe shade differentials with the naked eye. Observation in a darkened room with the use of an ultraviolet light makes it possible to differentiate twenty degree temperature effects, provided, of course, that the time factor is held constant.

Because the detector is enclosed in the plastic envelope, optical brighteners employed in detergents or laundry sour do not aifect these effects. However, if not enclosed in the envelope, the action of optical brighteners can be overcome by the following procedures.

Optical brighteners are dye stuff which are substitutes for blueing, generally used in household detergents. Two methods can be used to overcome this ditficulty:

(1) Use an ultraviolet light source, such as a mercury arc light in quartz, Whose radiation peaks in the vicinity of 2537 Angstrom units, instead of the conventional ultra violet light, whose peak radiation is in the vicinity of 3 600 Angstrom units.

(2) Use an orange filter. This orange filter, sold by the National Marking Machine Company, is for reading fluorescent laundry marks. A similiar Wratten optical filter No. G may be employed.

This detector No. 4 aids appreciably in evaluating detergent efliciency. Thermostat failures have been detected on automatic washing equipment with the use of this tester. Most commercial laundries use washing formulas that are approximately one hour in duration. An average of ten sudsing or rinsing operations is used. This tester measures combined time and temperature effects; hence,

the maximum temperature that has been attained during asuds bath of a washing formula cannot be determined unless the time and temperature of other steps such as the rinses have been held constant.

Detector No. 4 is not affected by soap, alkali, detergent, bleach, or laundry sour when applied cold. Suitable precautions must be observed in avoiding pressing the fabric when it is wet. The heat of a laundry press (315 F.) will distort washing temperature effects.

The changes in color with detector No. 4 are independent of bleach concentration orconcentrations of alkaline detergent, and are dependent only on temperature and time.

Temperatures of or more in excess of those specified in Formula 2, for the period of the formula, will cause a perceptible darkening of the visual shade of detector No. 4 or, under ultraviolet light, a decided loss in fluorescence. It is therefore desirable to establish a standard, by careful control of the washing cycle temperatures using a test swatch of detector No. 4, and use this as a standard of comparison with detector No. 4 in washing procedures in which this detector is employed.

It will make little difference, even if the detector is not enclosed in the envelope, whether subsequent washes em ploy brighteners different from those used in making the above standard run, since the comparison is in the same narrow range of the spectrum.

For identical temperature conditions, samples employed in baths with and without brighteners, when viewed under ultraviolet light and with a filter, show the same fluorescence intensity.

This fabric gradually develops a bluish cast at high temperatures. Low temperature washing (about 145) can be observed in ordinary light. An ultraviolet light is needed to detect 20 F. differentials when fairly high (180) temperatures are used. An orange filter, along with the ultraviolet light, is desirable to observe 20 F. differences when optical brighteners with a bluish cast have been added to the washing supplies. Brightener may also be transferred from soiled towels to the tester as the load is being washed. Restaurants often rinse out rented towels in household detergents that usually contain appreciable amounts of whitening agents.

Color changes with detector No. 4 under various conditions are given in Table XIV below.

Table XIV COLOR CHANGES WHICH OCCUR WITH THE PINK FABRIC (DETECTOR NO. 4)

The Plochere colors of detector No. 4 which can be seen with an ultraviolet light are shown below.

Comparison of these colors with actual washed swatches in a dark room would be difficult. It is suggested that separate detectors No. 4 be deliberately washed at low temperatures and at very high temperatures, and these can then be used to monitor detector No. 4 when employed in testing laundry operations.

Reasonable precautions are needed to avoid the crroneous assumption that high washing temperatures may have been used. When colored industrial fabrics are laundered, enough dye may be redeposited on this fabric to darken it, thereby giving abnormally high temperature effects. The whiteness of the backing, i.e., detector No. 8a, for these swatches, shows whether or not this has happened. The backing will also show if appreciable quantities of fluorescent brightener were present in the soiled load or the washing supplies. Brighteners with a blue cast under an ultraviolet lamp also give abnormally high temperature efliects, unless an orange filter is used.

Detector N0. 5 .Detector No. 5 is a temperature indicater composed of a piece of paper carrying a temperature-sensitive chemical which changes in color, and which color change is visible to the naked eye under ordinary daylight. This color change is dependent upon the time and temperature to which it is exposed and will indicate the effect of such exposure during a period of time at varying temperatures, or of varying durations of exposure at a fixed temperature. It may thus be termed a timetemperature indicator. It is chosen to give a change which will be detectably different if the temperature is abnormally low, normal or abnormally high for the duration of the laundry process during which the detector is employed.

A preferred detector is a paper impregnated with paint formed of boiled, i.e., an oxidized, linseed oil, mixed with a petroleum thinner, carrying as a pigment a mixture of anhydrous chromium chloride and also titanium oxide as a brightener. The paper is immersed in the paint and then air dried at an elevated temperature to remove the thinner. The chromium chloride, in its anhydrous form, is purple in color; and on exposure to steam or moisture, it picks up six molecules of water, but is still purple. On exposure to an elevated temperature in the laundry process, as described below, its color changes from purple to blue to gray and to green. This change is progressive and is a function of time and temperature, as will be more fully described below.

The paper may be enclosed in a plastic film, as in the case of detector No. 4.

Instead of using the above paper, we may use detector No. 4 as above, which also then acts in place of detector No. 5, and view the color change with 'an ultraviolet light. The fluorescence intensity is a measure of the time-temperature effect described above.

The detector is identified as 5 in FIGS. 1 and 2, and is in the sealed plastic envelope 113 and enclosed in the muslin envelope 14.

Table XV Shade change in ordi- Oolumn A Column B Column 0 Appearance of same Same fabrics that were nary light fabric in darkened room deliberately treated with with an ultraviolet light an optical brightener Row No. 1, unwashed detector: A treatment wigh a cod liriglliitener Plochere 388 Plochere 289 Ploehere 349.

solution would not chan e its appearance in or inary ay ig Row N0. 2: One washing with a formula No. 1 in the F. range. Munsell 7.5RP 5.0/8.0... Munsell 5.0R 4.0/0.0..- Plochere 357.

The chau "e in ordinary daylight is not very pronounce Row No. 3z One washing with a formula No. 3 in the range. The Plochere 443 Ploehere 386 Ploehore 341.

bluish cast begins to develop.

Row No. 4; Washing temperatures in 200 range (excessive heat) Plochere 451 Ilochere 433 Ploehere 397.

1 7 Table XVI COLOR CHANGES IN DETECTOR UNDER VARIOUS OPERATING CONDITIONS Merz and Paul colors (1) Color of original detector Plate 41-F-5. (2) Abnormally lowtemperatures for all treatments Plate 42-D-5.

except light soil formulas; for example, Formula Detector No. 6.--Detector No. 6 is an alkali-reaction intensity indicator composed of a textile such as a swatch of wool fabric or Wool yarn dyed with dye CI No. 45,100, which loses color without substantial color change and disintegrates progressively with increases in alkalinity for given periods of time. The degree of disintegration is a function of alkalinity and time. This indicator may thus be termed an alkalinity-time indicator. The fabric or yarn is enclosed in a piece of poplin. This poplin may, if desired, be treated to have a chlorine-sensitive finish. The above is more fully described below.

The reddish purple wool fabric, as described above, was dyed with a concentration of dye CI 45,100 [Wool Dye Red 748 or Acid Red No. 52 (Rhodamine B)-for constitutional formula see Colour Index], to give a color equivalent to ISCC-NBS No. 254, and preferably color equivalent to Plochere 43-4 or Munsell 7.5RP 3.9/13.

This fabric is made from a wool-like material which is unaffected by most bleaches, soaps or detergents, as well as hot soft water. The fabric is enclosed in fabric which is overfolded and formed into an envelope 15 by stitching 16 and connected to the fabric of 8a by a line of stitching 17, to protect it against mechanical action of the agitation and to retain the fabric even if it is disintegrated. It will withstand a brief cold soak in a washroom concentration (0.25% by weight) of a fairly strong alkali (orthosilicate). Higher concentrations or stronger alkalines first destroy the color and then destroy'the fabricitself. Its-small size reduces mechanical damage during the average washing formula. The small sack protects it from complete disintegration during the last part of heavy soil formulas or when alkali concentrations are fairly high.

Both time and temperature contribute to damage caused by alkali. They should remain constant if two different alkalies are compared. Only approximate pH values are shown below, because they are usually reducedduring the average break or sudsing operation, due to the presence of fatty soil. It should not be assumed that these pH values are the only desirable ranges for linen supply washing.

A mild alkali wash, suitable for woolens, does not destroy either the fabric or the ,dyestuif. The light soil washing, FormulaNo. 1, usually destroys the color,.but the fabric structure remains intact. A similar situation exists for the mediumsoil Formula No. 2. Most heavy soil formulas induce a partial disintegration of the woolen fabric itself. In a manner analogous to that of bleach baths, time, temperature and concentration affect the final appearance of the test fabric.

The degree of disintegration will be partiallyrelated to the rate at which the pH of the suds bath is lowered due to natural soil found in the fabrics being washed. Examination of the Formulas No. 1, No. 2, and No. 3 will show that the temperature of the Wash load must be raised by admitting live steam to the washer at operation step No. 2. Obviously, both the rate at which the temperature is raised and the rate at which alkalinity is lowered will affect the appearance of this fabric.

A concentration of 0.38% tetrasodiumpyrophosphate (SPP) and pure soap does not alter this fabric during a light soil formula, similar to Formula No. 3. A slight color loss occurs since pH values range from 10.2 to 9.8, using the standard glass electrode on an electric pH meter. A concentration of 0.13% of ordinary liquid hypochlorite bleach will not destroy either the color or fabric during an 8 minute exposure at F., when the pH values range from 9.8 to 8.3 during the bleaching bath.

The presence or absence of soap does not alter the end result significantly. A few nonionic detergents affect wool adversely, but they are not used extensively. On industrial washing classifications, such as shop towels or coveralls, there is a tendency for soil to collect on this woolen fabric Whenever the soil suspending power of the washingbath is lowered significantly.

Visual examination of this fabric does not permit decided differentiation between medium soil and light soil washing formulas. The green fabric in the large sack, described in detector No. 7, supplies the necessary information in this range of detergency.

The Pl0chere and Munsell color changes which occur as the reddish purple wool fabric of detector No. 6 loses color are shown in the following Table XVH.

Table XVII Row Ploohere Munsell 1 Original color 434 7.5RP 3.9 13 2, Med um soil washing without 437 2.5RP 6.2/12

alkali. pH range 9.8. 3 Medium soil washing with trl 440 5.0RP 9/8 sodium pyrophosphate and soap, pH range 10.2. 4 Normal light and medium soil Color gone but fabric is unformulas. altered. 5. Mild heavy soil formula Color gone, fabric is felted and has started to disintegrate. 6 Fairly severe heavy soil formula. 0231(1): gone, also most of the a no. 7 .Stain treat formulas with high Last traces of the fabric are alkalinity. gone; only the empty sack remains.

In the above Table XVII, the following explanations apply to items 1-7:

(1) Color of the original unwashed fabric. The cloth is soft and resilient.

(2) This indicates an example of the change with a low pH wash--about 9.5. This color produced resulted from employing a medium soil formula with the alkali purposely omitted.

(3) This color change is an example of a light soil formula employing pH about 10.0. The color was destroyed but the fabric is intact.

, (4) This change is an example of the use of an average medium soil formula, where the pH value is about 10.8 to 11.0. The color was destroyedybut the fabric is intact.

(5) This change resulted fromthe use of a mild heavy soil formula, with pH values of 11 .5 to 11.8. Many kitchen soil formulas partially destroy this fabric.

(6) This change is the. result of .a fairly severe heavy soil formula, with pH values in the 11.8 to 12.3 range.

19 Most of the fabric has been dissolved and washed away. (7) This change resulted from a formula employing excessive alkalinity with pH values in the 12.4 to 13.0

. 2i) The preferred form is a-green fabric, dyed with a concentration of dyes specified below, to give a color equivalent to I'SCC-NBS No. 151, and preferably color range. It completely destroyed both color and fabric. equivalent to Plochere 977 or Munsell 2.5BG 2.7/2.0; Only the empty sack remained. 5 The dyes are identified by Colour Index as follows: CI Industrial garment loads often contain, appreciable 30,295 (CI 7 Direct Green or C.B.M. No. 593); CI amounts of oil and soil. This, along with loosened dye 11,020 (Oil Yellow B.B.); Cl. 19,555 (Yellow B.W.P.). from colored garments, may redeposit on the fabric in- For the constitutional formulas of the above dyes, see the side this sack. In some cases this condition may lead to 10 "Colour Index. gray work or dull colors. Color loss of this direct cotton dyestuif has been found It has been observed that chlorine retentive finishes to correlate with the stain removal efficiency of washing that are applied to wash and wear cottons will retain formulas used for rental linens supplied by commercial very small quantities of bleach in the average washing laundries. A gradual increase in color loss can be obformulas. The retention of the bleach on the washed Ser ed in F mula N0, 1 through 4, dye is tered fabric will cause attack, if the fabric is cotton, and may b bl h so h an evaluation f detergent efliciency calls? fol-ting must be based on pigment loss rather than shade change. Wlth lesser Flmoums of bleach excesslve Pres This handicap does not prevent the fabric from provident, the effective concentration of bleach present may ing indicamion of detergent ffi i of formulas used often -be n the range of (1.005% or less. A speclfic tolaundel. salmnfirlable or fatty sol fa.bn R1ege1 s Shlp Ahoy poplin style made by As an aid to evaluate the degree of pigment loss, deglegel Texu'le Company 8 Gland cential tector No. 7 may be viewed visually by placing an untation, New York, New York, is chlorine retentive W h d f h d t t 7 l 1 f th d d t t enough to give a positive test with orthotoluidine when as ms 6 as M a ong 1 e 0 6 I it is dropped on to the fabric. The col 0 T-chan gfi is from on a light table composed of a frosted glass, illummated colorless to yellow to orange to red on the underneath side by fluorescent lamps. The de The stain removal formula shown in exhibit No. 2 gree of pigmem loss 15 Teadfly Observed Formula N0. 4 an operation involving the USE Industrial garments, such as coveralls or shop towels, of an .anti-c'hlor (usually sodium hydrosulfite). Riegel contain mineral oil that is best removed by emulsifica poplin is so chlorine retentive that it requires appreciable ti011 Father than sapollification- This test fabric is of quantities of sodium hydrosulfite to remove the last traces Value ill determining the q y of removal Of y of bleach. Hence, in this case, the sack used for hold- Stains, especially SW62"; stains, in the laundry P ing the wool fabric of detector No. 6, when made of cedure in which the detector is employed. such fabric,'becomes a monitor against inadvertent over- Perhaps the most important use for this fabric is that use of antichlors, which would destroy colors often found of a check or summary of the intensity of all other fac- 1n emblems and embmidefed name's that are used 011 tors which contribute to good detergency in laundering Tental 'garments- The T@5111 0Il llhiS fabTiQ is P y fabrics that contain restaurant or kitchen soil. If the urea'formaldehyde- The Amencan Dyestllfl Reporter: sudsing bath on a washing formula has been deficient 3 ,1950, dFsonbes chlorine and the bleach bath severe, this fabric Will change from ietenmve By usmg F fabilc for the l 40 green to brown or tan. If, on the other hand, the suds ope 15, the orthotoluene test, if applled to the fabnc, bath h be v d h t d alkald will indicate that there is residual bleach in the washed b en ery Severe U6 9 an 1*31} fabric. leaching effects are extremely mild, a green shade W111 Detector No. 7.Detector N0. 7 is an alkali-reaction Perslst even moilgh aplireclable (501m loss Ocwrs' intensity indicator composed of 'a textile such as a swatch The: loss pigment is proportional to the Stam of cotton fabric or a piece of cotton yarn dyed with a l i to bleach Bieachmg without dye or combination of dyes which changes in color and Pnor washmg changas amficlal SO11 from gpefln to loses color due to the combined effect of alkalinity, tembrown as can be Seen m the TOW, of Table perature and time. It thus measures the extent of the XV 1H belowone Washing will not remove all the alkali attack. This indicator may thus be termed an green Soil: as can be seen in Column A Table L alkalinity-time-temperature indicator, since it measures The nine Positions are desirable 1501' t linen the products of the effects of alkalinity, time and tempp P perature. The preferred dye is more fully described The fabric forming detector No. 7 is enclosed in a below. cloth envelope 18 and stitched to the detector 8a.

Table XVIII STAIN REMOVAL DETECTOR NO. 7 (Kitchen Soil) Column A B C D E Colors most often observed when- No bleach is used Bleaching is very Bleaching is moderate Bleaching is fairly Bleaching is severe mild intense or excessive I II I II I II I II I II 1) With t lk ztii E2) w aith? mmmrangia::::: i553? 213331323? 1333 1138313113 332 2338?? 3131313 3% fli ht? i3? ii iiiiiiii 3 W th moderate alkalinity..- 1036 6.58 5.7/2.7 1092 0.8G 5.8/2.0 1245 4.0GY 6.2/2.0 93 5.0Y 7.2/2.7 134 1.0Y 8.0/3.6 4 Fairlymtense alkalm1ty 1037 7.0G 6.6/3.0 1093 0.5G 0.9/1.5 1246 3.0GY 7.0/1.6 94 5.0Y 8.3/1.5 135 1.0Y 8.8/3.6 (5) 1 Severe or excessive alkalinity" 1094 10.0GY 7.6/1.0 1247 2.0GY 8.1/1.2 95 5Y 9/1 '136 1.0Y 9/3 88 3Y 9/1 1 This color is so close to white that it is difficult to designate it in the Munsell system.

Detectors 6 and 7 thus will report whether the tornperature is excessive or whether either alkali concentration or the time of treatment was excessive.

Detector 8 (white Indian head fabric) and detector 8a (poplin fabric).-Detector No. 8 is a mechanical action indicator composed of a textile such as a piece of white cotton sheeting pinked :at the edges which'is easily frayed by mechanical action, such as agitation and treating in the washer.

Detector Nos 8a is a mechanicallaction indicator com,- posed of a textile such as apiece of white poplin cloth, pinked at the edges, which is difficult to fray.

Thus, if detectors 8 and 8a are both frayed, either the agitation is excessive or was continued for too long a time. If 8 is frayed but not 8a, the agitation is excessive but the time of treatment is not too excessive. If neither isfrayed, both time and agitation areinsuflicient.

Since the mechanical agitation can be controlled so that, for normal operations requiring desirable periods of treatment, detector 8 is frayed lbut 8a is not frayed, the degree of fraying of 8 and 8a indicates the duration of the period of agitation. Detectors 8 and 8a can thus be termed agitation-time indicators.

It has been found desirable to attach detector 8 to the left side of the poplin fa'b-ric 8a which is used to hold the various detector fabrics. This makes it possible to compare pinked edges that are comparable in length (i.e., 8 and 8a) and observe excessive mechanicalpoundmg.

It has been observed that a pinked edge of an inexpensive grade of loosely woven Indian head cotton fabric, detector 8, will ravel out much more easily than the pinked edge of the poplin fabric-material, detector 8a, used for the backing of the colored swatches: The mechanical pounding of most formulas used by commercial laund-ries would make it impossible to tell whether or not the lower edge of the detector 8 hadbeen pinked prior to washing. The pinkededge of detector 8a, however, persists.

Time would exert a decided influence-on the degree of ravelling of both serrate-d edges. If the mechanicalad' tion of two different washers is beingtested, formula time should be comparable. The degree to which overloading restricts mechanical pounding can be evaluated by deliberately overloading and underloading two different pockets of the same washer, and including a detector in each pocket.

The chart shown 'below will serve as a guide in evalu- 2. ion. (2) Mild mechanical action.

(3) Normal mechanical action.

(4) Severe mechanical action.

Edge is frayed, pinking effects barely lsible v Cannot tell that the edge was pinked.

Frayed edges longer than on A-3 above.

Very slight fraying;

similar to A-l.

The outline of the pinked edge is still visible.

The edges are badly frayed, pinking effects are barely visible. Similar to A-2 above.

By using pinked edges for the large cloth as well as the small cloth, the degree of rave'lling indicates the degree of mechanical action.

Assume that we have a tester from a medium soil Formula #2, in which only a little color loss" is observed in detector No. 7, i.e., a match in row-#1 instead of row #3, Table XVIII. Also assume that both alkaline and temperature intensities are normal. That is, detector #4 shows a match in row 3, Table XIV; detector #5 in row 5; detector #6, row 5 in Table XVII; and detector 8 shows conditions equivalent to row 1 in Table XIX above, thereby indicating mechanical action that is deficient. If, however, detectors *8 and 8a show'undue mechanical effects,- row 4, Table XIX, while detectors4, 5 and 7 are the same as shown above, detector 6 will show deficient alkalinity and show a match in row 3, Table XVII.

As described above, detectors are most useful in showing not only what happens during a washing process, but give an indication of the intensity of these parameters. The following tables show five or six desirable goals ar-' ranged in rows for various types of Washing formulas. If Plochere cards are employed, it would be advisable to lay the cards out, side by side, as the following data is read.

In specifying a row in which the most desirable match will occur, it is necessary to use fractional numbers. For example, row 2.5 is a color between 2 and 3 for the heat detector 4 and would indicate washing temperatures between F. and F.

The following Table XX is an example of a desirable set of color matches for detectors which result from operations as indicated in the tables given below. The major parameters that are measured in detectors 1 to 8a will be as shown in Table XX.

Table XX Bleach Heat effects Alkaline Soil Mechanintensity removal ical action Mild Normal Severe Detector l 1 2 a 4 5 6 7 s and 8a The most desirable row for- Light soil 2 2 2 2. 5 3. 0' 3. 0 B-2 2. 5 Medium soil. 3 3 3 3.0 4. 0 4. 0 C 3 3. 0 Heavy soil 4 4 4 3. 5 6.0 5. 5 D-4 3. 5 Rewash or stain load. 5 5 5 3. 5 6.0 6.0 E-i 3.-5

1 Row refers torows 1-7 of Table XI, under detectors 1-3 respective 1y. 2 Row refers to rows 1-4 of Table XIV for detector #4 and Table XVI for detector #5. 3 Row refers to rows 1-7 of Table XVII for detector #6. 4 Row refers to column and row designation on Table XVIII for detector #7. 5 Row refers to rows 1-4 of Table XIX for detectors 8 and 8a.

ating mechanical effects. It was derived by using as a'comparative standard 42 x 96 open pocket washers that turn at 22 r.p.m., [have 7" ribs, and were loadedwith 350 pounds of towels (clean dry weight).

Having selected the rows in which the best match is likely to occur, it would be advantageousto select values that should not be exceeded in the event the plant operator finds it necessary to increase the intensity of his wash- Table XXI Detectors 1 2 3 4 5 6 7 8 and 82.

Row Row Row Row Row Row Row Row Normal light soil--. 2 2 2 2. s a. 3. 0 13-2 2. Using more bleach 3. 5 3. 5 3. 5 2. 5 3. 0 3. 0 D2 2. 5 Using more alkali. 2 2 2 2. 5 3. 0 5. 0 B-,-4 2. 5 Using more heat- 2 2 2 3. 5 6. 0 3.0 B-Z-l 2. 5 Using more agitation. 2 2 2 2. 5 3.0 3.0 B-3 3. 5 Using less heat with more alkali and agitation 2 2 2 2. O 1. 5 4. 5 B-2 3. 0

N0'rE.-Row designation as in Table XX. Fractional rows indicate a color match intermediate between rows, e.g., 2.5 means color intermediate that of row 2 and that of row 3.

The parameters that are most likely to cause damage to fabrics are bleach, alkali, heat, and agitation, in the order shown above. The operator of a plant will select the least costly combination for his particular plant in order to achieve a desirable goal. For example, if his boiler capacity is limited, he could use the last combination in Table XXI shown above, to achieve the desired B-2 condition with detector No. 7.

It may be that an exact color match with detector No. 7 may not be achieved, For this reason it is desirable to accumulate washed detectors and compare them with each other, as well as with the color cards. The methods used above can be applied to each of the various types of formulasmedium soil, heavy soil, and stain treatments. The desirability of employing detectors which mutually support each other in giving intelligence as to the operating conditions is illustrated by assuming unusual variations in formulas.

NOTE .Row designation as in Tables XX and XXI.

A casein point would be to assume that a supply house advocates low pH bleaching on medium soil formulas. The only way to achieve this is to use a milder alkali on the alkali suds bath, use more flushes prior to the bleach bath, or add a low pH buffer (probably acid phosphate) to the bleach bath itself. The most desirable row combination for medium soil is shown below, along with the changes that will occur.

(1) The use of added flushes prior to the bleach bath would increase the intensity of the bleaching effect from row 3 to row 4 with detector 3 on Table XI. At the same time, temperature effects and mechanical action would increase, since the formula would require longer duration of treatment.

(2) A milder alkali on the suds would cause an undesirable shift in detector 7 to condition C2 on Table XVIII. In this case the increased stain removal powers of the low pH bleaching probably will not make up for lower alkalinity on the suds bath, when fatty soil is being washed. However, such conditions may be desirable when doctor towels are being laundered.

' (3) This method of reducing alkalinity of the bleach bath allows the fatty stain removal powers of the original formula to remain undisturbed and still achieve a lower pH value during the bleach bath. The cost of the acid phosphate should be related to the savings due to lower rewash percentages.

THE LAUNDERING PROCESS EMPLOYING THE TESTERS OF MY INVENTION These detectors are used in combination to monitor the sudsing, rinsing following the sudsing, bleaching, rinsing after bleaching, and scouring off, to determine the efiect of alkalinity, temperature and time during sudsing, the adequacy of the rinsing operation after sudsing, the efiect of the sudsing and rinsing upon the bleaching operation, the eifect of pH, bleach concentration and quantity, temperature and time during bleach, and the effect of rinsing and souring oif after bleach-in other words, of the significant parameters which determine the character of the washing operation.

Detectors 4 or 4 and 5, together with 6 and 7, 8 and 8a, monitor the level of the sudsing operation, to wit, whether insufficient, normal or excessive.

As stated above, detector 4, if viewed in ordinary light, shows color changes if the temperature is abnormally low and substantially no change at higher temperature. Detector 5, if viewed in ordinary light, shows color changes if the temperature is abnormally high and shows no change at lower temperatures. Together they will indicate, when viewed in ordinary light, whether the temperature was abnormally low, normal or abnormally high.

Detector 4 may be used alone without using detector 5, This detector, when viewed under ultraviolet light the Wave length of which is 2537 A. or 36 00 A., will by its fluorescent color change, indicate whether the temperature was abnormally low, normal or abnormally high.

Detector 6 will indicate whether the combination of alkalinity and temperature which resulted was abnormally low, normal or abnormally high. This detector will not tell whether the temperature or the alkalinity were abnormally low or abnormally high or normal throughout the whole time of the exposure of the detector. Thus a high temperature and low alkalinity throughout the period of exposure may give the same result as low temperature and high alkalinity for like periods of time, or time may act in the same direction as alkalinity or temperature.

By using a combination of detector 4 viewed under ultraviolet light and detector 6, or when using detectors 4 and 5 together, when viewed under ordinary light, and also detector 6, the relative influence of temperature and the combined effect of alkalinity and time may be segregated, and it may be determined whether alkalinity was abnormally low, normal or excessive during the sudsing step.

To determine whether the alkalinity was abnormally low, normal or excessively high during the entire period of exposure, one may use detector 7, which shows color changes if both the alkalinity and the temperature were abnormally low, or both normal, or both excessively high throughout the Whole period of exposure of the detector in the sudsing peration.

This, however, will not tell whether the test results obtained with detectors 4, 5 and 6 were due either to the effect of temperature, alkalinity or time on the sudsing operation. To segregate whether time is the influence,

detectors 8 and 8a are employed, as has been previously 25 together with detectors 8 and 8a, as described above; The interpretation of other conditions will be evident from the foregoing description.

As stated above, the intensity of the bleach is determined by the soil entering the bleaching step, and this depends on the sudsing operations and the following rinsing operation prior to bleaching. The adequacy of the sudsing operation can be determined by the detectors 4, 5, 6 and 7, and 8 and 8a. As appears from the following, the bleaching operation is adversely affected by the excessive soil entering the bleach, and this must be caused by the inadequacy of the sudsing and rinsing.

Detector No. -'1 will report whether intensity is low or normal, but not whether it is excessive. It will not, however, report whether, if abnormally low, bleach intensity is the result of an abnormally low temperature or time or bleach concentration; and if it reports the bleach intensity as normal, whether the bleach concentration, time and temperature were mutually compensating to produce a normal bleaching effect.

Detector No. 2 will determine whether the bleaching intensity is normal or excessively high, but will not distinguish between the-two.

Detector No. 3 will indicate whether the bleaching intensity is excessive, but will not indicate whether this excessive bleach results from too high a bleach concentration, too high a temperature, or too long a time, but will report only that the combined effect of these parameters resulted in excessive bleaching action.

By using all three together, we can determine whether the bleaching intensity is normal, abnormally low, or abnormally high. It will not, however, give information as to the effect of the parameters which influence the bleaching result, but will report the integrated effect of all of the parameters acting during the bleaching operation.

To segregate the effect of these parameters, we use a fresh set of detectors at the start of the bleaching operation. FIG. 3 of the drawing shows an assembly consisting of detectors 4, 5, 6, 7, 8 and 8a. By introducing a second such set of alkali, time and temperature detectors, the intensity of each, or their conjoined action, will be monitored during the bleaching step. Normally, there will be a decided contrast in intensity between the two sets. The magnitude of these diiferences will provide the reason for abnormalities in bleaching intensity.

Thus, if bleach intensity is abnormally low, two sets of detectors may be used on future tests to determine the cause. The entire assembly FIG. 1 will be referred to as set No. l, and the set shown in FIG. 3 as set No. 2.

If set No. 1 shows normal alkalinity, time and temperature, and set No. 2 shows very little change, it is clearly evident that a failure to rinse out the soil loosened on the sudsing step caused the bleaching intensity to be low. However, if there is very little contrast between the alkali, time and'temperature detectors of set No. 1 and set No. 2, it is proof that the sudsing step was deficient, and that alkalinity, time and temperature of the bleach bath was excessive. The reason that these conditions do not increase the overall bleaching intensity is the fact that bleach will be destroyed by the loosened soil, and thereby not be available to alter the bleach sensitive detectors.

Variations in bleaching intensity on different sections of the same towel, for example, may be noted by including square yard sections of the dyed fabric of detectors 1 and 2. A decided mottledeffect will be observed when there is an attempt to carry out a sudsing and bleaching operation simultaneously.

If the combined effects of soil and bleach are low, the green fabric of. detector 1 will have black areas. If excessive bleach is used, both the green and light blue fabric (detector 2) will be mottled in appearance.

The addition of square yard pieces of bleach-sensitive 2efabr-ic is unnecessary -tomonitor normal washing formulas. The combined use of set No. 1 and set No. 2 is reserved for. conditions in which the bleaching intensity is unaccountably low.

If the sudsing operation was normal according to the report of detectors 4 to 8a, and the detectors. 1. to 3. show an abnormal condition in the bleach, this abnormality may be the result. of an abnormality in the parameters of alkalinity of a bleach bath, and the temperature and time, and their levels during their conjoined action present during the bleaching operation.

OTHER USES In the previous discussion, I have described the use of my detectors as indicators wherein they are structurally separated from the wash load byadding them in a tester to the wash load. However, it is possible to combine them with the fabric to be washed, as by sewing them to the fabric. An alternative is to interweave them with the fabric'by dyeing theyarn with the dyes as described above.

Thus, as an example only, yarn dyeings have been prepared of three vatdyes used to detect bleaching intensity of detectors 1, 2 and 3, thus producing three'yarn strands so dyed. It would be possible for a cotton mill to incorporate the three colors of detectors 1-3- into a stripe or hem of a towel. It would serve the very useful purpose of giving anindication of the bleaching intensity to which the towel has been subjected.

The dark green detector 1 would turn black and remainthat way for the life of the towel. The light blue detector 2 becomes colorless under normal light after two or three stain removal treatments; especially if the pH of the bleach bath is low. However, the bleached yarn, which is colorless under ordinary visuallight, will appear colored when viewed with the aid of an ultraviolet lamp. The dark blue yarn detector 3 would serve as an excellent monitor in guarding against over-bleaching, and probably be visible during the entire service life of the fabric. These yarns could be used to sew pocket seams, etc., on white cotton garments. They would be inconspicuous and serve as a monitor of'bleaching eifects.

A cotton mill or bleachery may find these yarns extremely valuable in monitoring J-box bleaching. Commercial laundries that rent cotton goods may find it advantageous to request these yarns in stripe form on towelling or in the selvage of cotton yardage. It would furnish proof that the mill or bleachery has not prepared fabrics that were bleached at low pH values.

These detectors may be employed as an aid in evaluating the comparative efiiciency of two different washers or washing supplies.

Many textile chemists have pointed out the difficulty of evaluating comparative detergent efiiciency of two different washers or washing products.

It is necessary to exercise very careful control over the operators who sort and classify linens prior to sending them to the customer. In most laundries it is impractical to reject minor stains which are acceptable to the customer. It is necessary to rely upon the judgment of employees in maintaining uniform quality. A constant quality standard must be maintainedwhile stain treat percentages are being accumulated. Daily variations are quite large, and several. months are required to accumulate data with statistical significance in evaluating the comparative efiiciency of washers and detergents and washing formulas. Thus, it becomes apparent that the costof evaluating minor changes. in either supplies or washing equipment would exceed that of the resultant savings. Detectors can aid significantly in eliminating. trial and error methods of intensifying parameters related to supplies or equipment. They are also an invaluable aid when the effluent from washing. baths is titrated for alkalinity, residual bleach', and .the like;

Detectors may be used to determine whether various 27 portions of the washer vary in rinsing rates and bleaching intensity when all of the water enters the machine from one end, instead of in the middle. Uneven bleaching intensity usually occurs, as evidenced by the mottled appearance of the detector fabric.

Dyeing for many years has been considered an art rather than a science. To a lesser degree, washing had followed the same pattern. A set of rules regarding parameters that contribute to fabric damage had been established. Detectors permit a quantitative evaluation of these effects. As an example: Dr. Pauline Berry Mack, editor of Fellowship Reports (a monthly publication for Linen Supply Laundries), cautions members about the damage caused by high temperature rinsing after the bleach bath-operation step No. 8, Formula No. 3; or operation step No. 6, Formula No. 2. Detectors have demonstrated that the concentration of bleach carried over into this step is so low that for all practical purposes it can be ignored. They have also shown that damage formerly attributed to high temperature rinses following the bleach bath was far more likely to be caused by the unevenness of bleaching intensity than from the use of multiple suds washing formulas recommended by the American Institute of Laundering.

Detectors have been used to monitor the intensity changes of bleaches other than hypochlorite. Both dichlorodimethylhydantoin and trichlorocyanuric acid will alter all three of the bleach-sensitive fabrics in substantially the same way. The slower decomposition rate of these bleaches can be demonstrated by using a detector during and another after the bleach bath.

Most oxygen bleaches do not affect the three test fabrics, detectors 1-3. Formulations of oxone based on potassium monopersulfate do not alter the color of detectors 1-3, unless sufficient salt (NaCl) is added to provide a hypochlorite ion. Even under these circumstances, the color loss in detector 2 is very slight.

While I have described a particular embodiment of my invention for purposes of illustration, it should be understood that various modifications and adaptations thereof may be made within the spirit of the invention, as set forth in the appended claims.

I claim:

1. A laundry tester for determining the intensity of a sudsing operation in a laundry process comprising:

(a) a cotton textile enclosed in a water-permeable and dye-impermeable plastic envelope, said textile being dyed with a dye classified by the Color Index No. 16,605 to a color substantially equivalent to a color classified as ISCC-NBS No. 248;

(b) an alkali-reaction intensity indicator comprising a wool textile dyed with a dye classified by Colour Index No. 45,100 to a color substantially equivalent to a color classified as ISCC-NBS N0. 254;

(c) an alkali-reaction intensity indicator comprising a cotton textile dyed with a dye mixture composed of a dye classified as Colour Index No. 30,925, containing minor amounts of dyes classified as Colour Index No. 11,020 and Colour Index No. 19,555, to a color substantially equivalent to a color classified as ISCC- NBS No. 151; and

(d) a mechanical action indicator comprising a piece of cotton sheeting and a piece of poplin both pinked at their edges.

2. In the tester of claim 1, in which:

(a) said color equivalent to ISCC-NBS No. 248 color is a color substantially equivalent to a color classifield as Plochere 388; and

(b) said ISCC NBS No. 254 color is a color substantially equivalent to a color classified as Plochere 434; and

(c) said ISCC-NBS No. 151 color is a color substantially equivalent to a color classified as Plochere 977.

3. In combination with the tester of claim 1, a temper- 28 ature indicator comprising a piece of paper colored with a paint pigmented with anhydrous chromium chloride.

4. In .the tester of ,claim 3, said paper having a color substantially equivalent to a color classified as a Merz and Paul color at Plate 41-F-5.

5. In combination with the tester of claim 2, a temperature indicator comprising a piece of paper colored with a paint pigmented with anhydrous chromium chloride.

6. In the tester of claim 5, said painted paper having a color substantially equivalent to a color classified as a Merz and Paul color at Plate 41-F-5.

7. In combination with the tester of claim 1;

(a) a bleaching intensity indicator formed of a cotton textile dyed with a dye classified by the Color Index No. 59,850, to a color classified as ISCC-NBS No.

(b) an alkali-reaction intensity indicator formed of a cotton textile dyed with a dye classified by the Colour Index No. 74,140, to a color identified by ISCC-NBS No. 168; and

(c) a bleaching intensity indicator formed of a cotton textile dyed with a dye classified by the Colour Index No. 73,065, to a color classified as ISCCNBS No. 194.

8. In the tester of claim 7, in which:

(a) said ISCC-NBS No. 145 color is a color substantially equivalent to a color identified as Plochere 1034; and

(b) said ISCCNBS No. 169 color is a color substantially equivalent to a color identified as Plochere 771; and

(c) said ISCC-NBS 'No. 194 color is a color substantially equivalent to a color identified as Plochere 625.

a 9. In the tester of claim 7, in which said ISCCNBS No. 145 color is a color substantially equivalent to a color identified as Munsell 6.06 3.8/2.5, and said ISCC-NBS No. 169 color is substantially equivalent to a color identified as Munsell 6.0B 4.9/9.0, and said ISCO-NBS No. 194 color is a color substantially equivalent to a color identified as Munsell 8.0PB 2.8/14.

10. A process of laundering comprising:

(a) mechanically agitating soiled wash in an aqueous alkali solution of a detergent at an elevated temperature for a period of time in the presence of a tester defined as in claim 5;

(b) withdrawing the alkali solution;

(0) rinsing said wash at an elevated temperature; and

(d) controlling the temperature during said washing such that (i) the temperature-sensitive textile with an initial color of Plochere 388, referred to in (a) of claim 2, changes in color to give a color having a higher Plochere number but less than a Plochere No. 451, when seen under ultra-violet light; and

(ii) said paper referred to in claim 3 changes in color but has a color intensity classified as a Merz and Paul color in Plates 43 to 46; and

(e) controlling the alkalinity (i) to substantially destroy the color of the textile referred to in (b) of claim 2; and

(ii) the color of said textile referred to in (c) of claim 2, changing to increase its Plochere number but to less than a Plochere No. 1094; and

(f) continuing said agitation for a time and with a degree of mechanical agitation to substantially remove the pinking on the white cotton cloth, without entirely removing the pinking of said white poplin cloth referred to in (d) of claim 1.

11. A process of laundering, employing a sudsing and a bleaching step, which comprises:

(a) agitating soiled wash in an aqueous alkali solution of a detergent at an elevated temperature for a period of time in the presence of a tester as defined in claim 8;

(b) withdrawing the alkali solution;

() rinsing said Wash and said tester at an elevated temperature;

(0.) adding a solution of a bleaching agent to said rinsed wash and tester;

(e) agitating said wash and tester in said bleaching solution at an elevated temperature and for a prolonged period of time;

(1) controlling the temperature such that (i) the temperature-sensitive textile, referred to in (a) of claim 2, changes in color to give a color having a higher Plochere number but less than Plochere 451 when seen under ultra-violet light; and

(ii) said paper referred to in claim 3 changes in color but has a color intensity classified as a Merz and Paul color in Plates 43 to 46; and

(g) controlling the alkalinity to substantially destroy the color of the textile, referred to in (b) of claim 2, and the color of said textile, referred to in (c) of claim 2, changes to increase its Plochere number to less than 1094; and

(h) controlling the bleach concentration, temperature and agitation during the bleaching step to (i) change the color of the textile, referred to in (a) of claim 8, to a black color, and the textile referred to in (b) of claim 8 to a higher Plochere number but less than Plochere No. 776; and

(ii) change the color of the textile, referred to in (c) of claim 8, to a higher Plochere number but but less than Plochere No. 628; and

(i) continuing said sudsing and bleaching steps for a time sufficient to remove the pinking of said white cotton fabric without entirely removing the pinking of the White poplin fabric.

12. In the process of claim 11, in which said Wash and tester are agitated with said bleaching solution in the presence of another tester as defined in claim 1, and in which the color changes in the textiles of said other testers are substantially the same as the like-colored textiles of the first-mentioned testers.

13. In the process of claim 2, in which said wash and tester are agitated with said bleaching solution in the presence of another tester as defined in claim 1, and in I which the color changes in the textiles of said other testers are substantially the same as the like-colored textiles of the first-mentioned testers.

14. In the process of claim 3, in Which said Wash and tester are agitated with said bleaching solution in the presence of another tester as defined in claim 1, and in which the color changes in the textiles of said other testers are substantially the same as the like-colored textiles of the first-mentioned testers.

15. In the process of claim 4, in which said Wash and tester are agitated with said bleaching solution in the presence of another tester as defined in claim 1, and in which the color changes in the textiles of said other testers are substantially the same as the like-colored textiles of the first-mentioned testers.

16. In the process of claim 5, in which said Wash and tester are agitated with said bleaching solution in the References Cited in the file of this patent UNITED STATES PATENTS 2,278,339 Vollmer Mar. 31, 1942 2,308,087 Lappala Jan. 12, 1943 2,567,445 Parker Sept. 11, 1951 2,663,692 Corso et al Dec. 22, 1953 2,799,167 Loconti July 16, 1957 2,880,070 Gilbert et al. Mar. 31, 1959 Jordan Oct. 31, 1961 OTHER REFERENCES Better Laundering, Procter and Gamble, 1949, pp. 98109.

fI-Iydrion pH, 1958 Catalog of pHydrion.

Claims (1)

1. A LAUNDRY TESTER FOR DETERMINING THE INTENSITY OF A SUDSING OPERATION IN A LAUNDRY PROCESS COMPRISING:

Images