US3186869A - Coated film for laundry package - Google Patents

Description

June 1, 1965 J. FRIEDMAN COATED FILM FOR LAUNDRY PACKAGE Filed Jan. 29, 1962 FIG.2

INVENT OR.

ATTORN ES 3,186,869 CQATED FETJM FQR LAUNDRY PACKAGE lack Friedman, 250 Kensington Ave, iontreal, Quebec, Canada Filed ran. 29, 1962, S61. No. 169,316 19 Claims. (Cl. 117--138.8)

The present invention is a continuation-in-part of application Serial No. 90,959, filed February 23, 1961, entitled Laundry Package, now abandoned, and relates to a water soluble package adapted to contain corrosive or volatile compounds. More particularly, the present invention is useful as a water soluble package containing a bleach and, if desired, a detergent or soap, for laundry use.

Heretofore, packages have been used for laundry purposes which comprise a water soluble bag containing detergents and a weak bleaching agent. Such bags have particular appeal for home use where a measured amount of bleach and detergent may be thrown into a laundry machine without waste or mess. Such packages are intended to provide the required amount of bleach and in most cases detergent required for a single filling of the machine. Unfortunately, such packages are inefiicient because Weak bleaching agents, such as oxygen containing compounds must be used.

Some attempts have been made to improve these laundry packages by using stronger bleaches, and in particular by using chlorine bleaches. However, these stronger bleaches and in particular chlorine bleaches, react with the material which has heretofore been used to form the walls of the package. Chlorine bleaches will react with every known water soluble film useful for such packaging including, for example, polyvinyl alcohol, methyl cellulose, carboxymethyl cellulose and film derivatives of polyethylene glycol. When a chlorine bleach reacts with this film forming material, it becomes insoluble and loses its disintegrating or dissolving properties. Consequently, if the package is allowed to stand long enough, it will not satisfactorily dissolve when thrown into the laundry water.

The present invention overcomes such difiiculties, and provides a package containing a strong bleaching compound, preferably a chlorine containing bleach, which has an indefinite shelf-life, and in which the packages does not react with the bleach. The present invention also provides a water soluble laundry package adapted to contain detergents and/ or a chlorine bleach, in which the package will readily dissolve in water and in which the package material will not react with the bleach and thereby become insoluble.

A further object of the present invention is to provide a coated film material which is particularly useful for containing highly reactive oxidizing agents, such as chlorine containing bleaches without the likelihood of the coated film material reacting with the bleach.

These and other objects and advantages of the present invention will be more clearly understood when considered in conjunction with the accompanying drawings, in which:

FIG. 1 is a plan view of a laundry package embodying the invention, and

FIG. 2 is a cross sectional view taken along the line 22 of FIG. 1.

As illustrated in the drawing, the laundry package of the present invention may be formed of a thin Walled flexible bag havingflexible walls 3 of water soluble film forming material, whose inner surfaces are provided with a Waterdispersible barrier coating 2, which is non-rective with the bleach and/ or detergent material 1 contained Within the package. Theflexible Walls 3 may be heatsealed together about theirperipheral margins 4.

3,l8fi,8fi0 Patented June 1, 1965 Thewall 3 formed by the film forming material is of bag thickness, preferably from about .001 to approximately .003 of an inch in thickness. A typical bag may have overall dimensions of 2 1" by about 4 /2", with a heatsealed margin i of approximately /3". These figures are examplary and may be varied depending upon the particular use desired. Thebarrier coating 2 is contiguous with thewall 3 and forms a complete covering for its inner surface. The thickness of thebarrier coating 2 is preferably in the range of about .001 to .003 of an inch, but this may be varied depending on the particular use and content of the bag. 7

The film forming material may comprise any of a number of water soluble film forming materials which are generally used to package laundry material in water soluble packages. Such film forming materials includes, for example, polyvinyl alcohol, preferably plasticized: methyl cellulose; 21 carboxymethyl cellulose such as sodium carboxymethyl cellulose; sodium carboxymethylhydroxyethyl cellulose; or, a film derivative of polyethylene glycol. Other film forming materials such as set forth in Canadian Patent 510,555, issued March 1, 1955, or comprising high molecular Weight polymeric materials containing water solubilizing groups or hydrophilic groups, such as hydroxyl groups or carboxylic groups may be useful even though they are reactive with strong bleaches and in particular with chlorine, providing they are coated with a barrier as described herein.

Thebarrier coating 2 is preferably formed of a Wax or oleaginous substance, for example, a wax selected from the group consisting of hydrocarbon, microcrystalline, animal and vegetable Waxes, saponified fatty acids, saponified fatty acid esters, condensation products of ethylene oxide, esters and mixtures of these and similar substances. The material forming the barrier coating should melt between room temperature of approximately 68 F. and the boiling point of water, 212 F. and preferably should melt in hot water in a melting temperature range preferably of about F. to about F., but this depends upon the specific nature of the coating material. This barrier coating material should be water dispersible. it functions to seal the inner surface of thewalls 3 from contact with the bleach material. Since the barrier material which preferably comprises paraffin is itself not water soluble, it should preferably have incorporated or homogeneously dispersed throughout, a dispersing agent which will, upon wetting of the bag, cause the barrier material to disperse in colloidal form. Since the barrier material does not have structural strength, it Will readily break up when the film forming material dissolves in water. The barrier material will thereupon disperse in the water in colloidal form, releasing the contents of the package into the Water. This Wax or oleaginous substance comprises the major portion of the barrier coating and preferably constitutes up to approximately 85 by weight of the coating.

Preferably mixed with the wax or oleaginous substance is an emulsifier, a film forming material, and/ or a softener. The function of the emulsifier is to assure a suitable colloidal dispersion of the barrier coating when the bag is immersed in water so that the barrier coating material will not interfere with the washing process. Preferably a film forming material is incorporated into the barrier coating. This film forming material is intended to assure a uniform and consistent barrier coating which is not likely to break or crack during application or stor-- age. It is also useful to incorporate a softener into the barrier coating, for purposes of assuring flexibility of the barrier coating so that it will not crack or otherwise become defective during handling or storage of the laundry package. Certain materials may have a dual function as such an emulsifier, film forming material or softener.

Suitable emulsifiers comprise, for example, various nonionic surface active agents such as, glycerol monostearate. Other synthetic emulsifiers include salts of fatty acids, as for example, salts of oleic or stearic acids. Triethanclamine has also been found to be a suitable emulsifier. These compounds may also be used in various combinations with one another for specific desired effects. The emulsifier may preferably comprise up to approximately 20% by weight of the barrier coating.

Glycerol monostearate has also been found suitable as a film forming material and may preferably constitute up to approximately 20% of the total weight of the barrier coating.

In place of glycerol monostearate, other nonionic emulsifiers or surface active agents may be used and substituted as emulsifiers. Such materials include materials referred to on page 970 of Merck Index, 7th Edition, copyright 1960 under the definition of Span and Tween. Ionic surface active agents, as for example, salt of fatty acids, such as the reaction product of oleic and/ or stearic acid with triethanolamine and/or morpholine may be used. Such substitutes may be used in the same range as glycerol monostearate.

Suitable softening agents include for example, lanolin and petroleum jelly. Other softening agents may be used in place of petroleum jelly or lanolin, provided they are chemically inert with respect to the chlorine or other bleaches and detergents contained within the package, and provided they are chemically compatible with the paraffin. Such a softener may comprise up to approximately 25% by weight of the barrier coating.

The materials referred to above may perform multiple functions. For example, as indicated, glycerol monostearate may function both as an emulsifier and a film forming material, while lanolin may function both as an emulsifier and as a softener. This multiple utility permits a wide range of compositions in the barrier coating. However, any of the materials used in the barrier coating must be chemically inert with respect to the material contained within the package, and other materials normally encountered in washing. The materials of the barrier coating must be emulsifiable on dissolution of the supporting film and must be flexible or capable of being made flexible in film form.

The composition comprising the barrier coating may comprise merely the wax or oleaginous material. However this composition is not as satisfactory as a composition containing the emulsifier, fllm forming material, and/ or the softener for reasons set forth above.

The barrier coating material should comprise a homogeneous mixture of the materials referred to and may be applied to theflexible walls 3 at a temperature just above melting point of the barrier coating material. The coating operation may be performed in any suitable manner, as for example, by roller coating, or spraying. The thickness of the barrier coating will depend upon the method and temperature used.' A preferred coating temperature is within the range of 130 F. to approximately 160 F. This again will depend upon the specific composition of the barrier coating material.

The contents ofthe package, preferably comprise in combination, a synthetic detergent and a chlorine containing bleaching agent. In addition, it has been found useful to include an alkaline source, a washing aid, a stabilizing water softener sequestering agent, a soil suspending agent and an optical bleach. The synthetic detergent and chlorine conatining bleaching agent are com,-

bined in such a manner as not to decompose when mixed act with chlorine or chlorine releasing agents. Since chlorine is a strong oxidizing agent, detergents that are oxidizable or strong reducing agents should not be used.

Various suitable detergents include for example, alkali metal salts, ammonium salts and ethanolamine salts of 7 will of course, function only as a bleaching agent. The contents, which includes the detergents and chlorine con- 7 in dry form and packaged within the packaging material.

sulfonated higher alkyl mononuclear aryl hydrocarbons, having from 9 to 18 carbon atoms, for example, sodium dodecylbenzene sulfonate, alkali metal salts of fatty acids such as sodium oleate and sodium palmitate. Other synthetic detergents commercially available may also be used.

Thebleach should be a strong oxidizing agent and preferably comprises a chlorine containing bleaching chemical. This bleach must be solid at room temperature and must decompose water to release the bleaching agent, preferably chlorine. Suitable chlorine donor materials may comprise, for example, dichloroisocyanuric acid and tricmoroisocyanuric acid. Other chlorine releasing agents,

such as lithium hypochlorite and calcium hypochlorite, as

referred to in British Patent No. 606,431, issued to William H. Langdwell, August 13, 1948, are also useful.

A source of alkalinity may be provided from a compound selected from a group consisting of anhydrous sodiurn metasilicate, anhydrous potassium metasilicate, various metal phosphates or polyphosphates, such as sodium or potassium phosphates, or trisodium phosphate anhydrous may be useful. In addition to various other polyphosphates of sodium or potassium, sodium carbonate may also be used as an alkaline source. The alkaline source is optional and is useful primarily as an aid in the washing process. It has been found that soaps or detergents, ionize better in alkaline media. This alkaline source also functions to aid in stabilizing a chlorine containing material in the combination. A suitable washing aid such as anhydrous tripolyphosphate may also if desired, be included in the composition. This washing aid functions to keep complex heavy metal ions from precipitating when the package is dissolved in water.

A similar function is performed by the stabilizing water softener sequestering agent. Such agents may include for example, sodium tetraethylenediamine tetra-- acetic acid. A soil suspending agent, as for example, carboxymethyl cellulose may also be incorporated into the composition, together with an optical bleach such as products marketed under the names Calcofluor and Tinopal. The soil suspending agent and the optical bleach are conventional in washing compounds and their use is not critical. If desired various inert fillers such as sodium sulphate may also be used.

If present, the detergent preferably comprises from about 10% to about 20% by weight of the total mixture;

the alkalinity imparting compound preferably comprises up to about 25 to 35% by weight of the total mixture; the chlorine donor material comprises by weight at least 5% of the total mixture; the washing aid is employed in amounts up to about 25% to about 35% by weight of the total mixture; the stabilizing sequestering agent is used in amounts up to about .10% to about 2.5% by Weight of the total mixture; the soil suspending agent may be used in amounts up to about .5% to 1%, and the optical bleach maybe used in amounts of up to about .2% to .5 Each of these amounts are weights of the total composition.

While the foregoing percentages suggest a preferred range for a combination composition of a detergent and chlorine containing chemical, the package may consist in one embodiment, of the packaging material and a chlorine containing bleaching chemical alone. This composition taining chemical in the preferred embodiment, are mixed In preparing the composition, which includes the detergent and chlorine containing chemical, the constituents are weighed out, dried, and put through a sieve in a mixer, for example a Day-Type. The ingredients are thus mixed together thoroughly, forming a uniform dry powder. There is no mixing problem. T his procedure is carried out in a dry room having for example, less than 50% humidity at room temperature. The exact temperature and humidity is not critical. The mixed composition is then fed to a hopper in the packaging machine which makes the packages and then fills and seals them in a conventional manner. These packages, which are formed of the coated film material previously described, are water soluble and consequently dissolve readily when the package is placed in Water. When the package disintegrates there is no deposit left on the wash.

Various examples will more fully describe the scope of the present invention.

Example 1.The supporting film is formed Of polyvinyl alcohol having a thickness of two mils. ing film composition is a mixture of glycerol monostearate, oleic acid and triethanolamine. The preferred concentration of the glycerol monostearate is 85%, the oleic acid 5% and the triethanolamine However, the permissible range of glycerol monostearate may vary from about to about 85%, the oleic acid, 3% to 10% and the triethanolamine from 1% to 10% by weight of the total composition.

The glycerol monostearate presumably functions in this example primarily as a film forming material. The oleic acid and the triethanolamine in combination form an emulsifier (oleic acid triethyl ammonium salt). Other surface active agents, nonionic or ionic may be substituted for the oleic acid and triethanolamine. If desired, the composition may include lanolin or petroleum jelly or other softeners to give greater flexibility to the film. If included, such softeners should not exceed about of the total composition by weight. The composition is mixed preferably at -a temperature of 130 F., but a range of 130 F. to 140 F. is satisfactory. The coating material was applied to the supporting film by passing the film over rollers running in a bath of melt at a temperature of about 140 F., with a range of 150 F. to 180 F. being permissible, so that a film having a thickness of approximately .002" is applied to the supporting film. The barrier coating solidifies almost immediately. Supporting film carrying the barrier coating may be led to a package forming and filling machine, and packages are made continuously having dimensions of approximately 2%" in width and about 4 /2" in length, with a heat sealed margin of about The washing compound which fills the bags may contain a combination of a detergent in the range of 10% to 20%, an alkaline source in the range of 25 to a chlorine donating chemical of at least 5%, a washing aid in the range of 25% to 35% and a stabilizing water softener sequestering agent in the range of .l% to .25 all by weight. These materials forming the washing compound are selected from one of the aforementioned compounds.

Example 2.-A package made in accordance with Example 1 was thrown into a washing machine containing water at a temperature of 130 F. The supporting and barrier films of the bag dissolved quickly and released the contents into the wash water.

Example 3.A preferred coating material is made up from the following constituents, the percentages being the weight of the total composition.

Percent Glyceryl monostearate 10Lanolin 2 Parafiin 65 Petroleum jelly 23 The coat-v form a homogeneous molten mass. A polyvinyl alcohol film was coated with this mass at 160 F. Bags were made from the coated film and filled with detergents and chlorine containing bleach. The bags were tested as described in the previous examples. It was found that the coating material effectively prevented reaction between the chlorine of the washing compound and the polyvinyl alcohol, and that the bags dissolved freely when thrown into the water of a washing machine.

In addition, it has been found that coating made in accordance with the present invention also effectively prevent deterioration of bags containing detergents or other Washing compounds alone, which in the absence of the coating described, would deteriorate the bag over a period of time.

What is claimed is:

1. A film comprising a continuous base film of a watersoluble synthetic organic film-forming material normally reactive with chemical bleaching and washing agents provided with a thin continuous barrier coating capable of being emulsified and having a water-dispersible waxy maerial containing an emulsifier, said waxy material being non-reactive with such agents,

said barrier coating adapted to prevent the reaction of the agents with the substance of the supporting film, said emulsifier being present in sufiicient quantity to act as a dispersing agent for said waxy material,

the composite film being adapted to disperse in water at a temperature in the range of from 68 F. to 212 F.

2. A film in accordance with the film of claim 1 Wherein said water soluble film-forming material is selected from the group consisting of polyvinyl alcohol, methyl cellulose, carboxymethyl cellulose and a water soluble film forming derivative of polyethylene glycol.

3. A film in accordance with the film of claim 1 wherein said barrier coating melts at a temperature in the range of about F. to F.

4. A film in accordance with claim 1 wherein said barrier coating comprises in approximate percentages by weight:

5. A film in accordance with the film of claim 1 wherein said barrier coating comprises in percentage by weight from about 20 to 85% glycerol monostearate, about 3- 10% oleic acid and about 110% triethanolamine.

6. A film in accordance with claim 1 wherein said barrier coating contains a film forming material.

7. A film in accordance with claim 1 wherein said barrier coating contains a film forming material and a softener for said barrier coating.

8. A film in accordance with the film of claim 7 wherein said waxy material is selected from the group consisting of hydrocarbon Waxes, microcrystalline waxes, animal waxes, vegetable waxes, saponified fatty acids, saponified fatty acid esters and condensation products of ethylene oxide.

9. A film in accordance with the film of claim 7 wherein said waxy material is parafiin.

10. A composite film comprising a continuous base supporting film of a water-soluble synthetic organic filmforming material normally reactive with chemical bleaching and washing agents provided with a thin continuous barrier coating capable of being emulsified and having a water dispersible waxy material containing an emulsifier,

said waxy material being non-reactive with such agents,

said barrier coating adapted to prevent the reaction of the agents with the substance of the supporting film,

said emulsifier being present in sufiicient quantity to act as a dispersing agent for said waxy material,

said barrier coating having a thickness of from between approximately 1 to 3 mils,

the composite film being adapted to disperse in Water at a temperature in the range of from 68 F. to 212 F.

References Cited by the Examiner UNITED STATES PATENTS 2,436,433 2/48 Jebens. V 2,495,283 1/50 Werntz 117168 XR 2,655,480 10/53 Spitzer et a1 252--90 2,636,008 4/53 Iurgensen et a1. 25293 2,778,748 1/57 Rowe et 211.

2,841,572 7/58 McMahon 252-90 XR 8 2,995,521 8/61 Estignard-Bluard 252-90 3,079,640 3/63 Kawai et a1.

FOREIGN PATENTS 5 510,555 1/55 Canada.

550,865 12/57 Canada. 7

20,116 1889 Great Britain.

OTHER REFERENCES Elvanol (Polyvinyl' Alcohols), issued by E. I. du Pont de-Nernours and Co., Inc., 1947, p. 17. 7

WILLIAM D. MARTIN, Primary Examiner.

J. FREEMULD, RICHARD D. NEVIUS, Examiners.

Claims (1)

1. A FILM COMPRISING A CONTINUOUS BASE FILM OF A WATERSOLUBLE SYNTHETIC ORGANIC FILM-FORMING MATERIAL NORMALLY REACTIVE WITH CHEMICAL BLEACHING AND WASHING AGENTS PROVIDED WITH A THIN CONTINUOUS BARRIER COATING CAPABLE OF BEING EMULSIFIED AND HAVING A WATER-DISPERSIBLE WAXY MAERIAL CONTAINING AN EMULSIFIER, SAID WAXY MATERIAL BEING NON-REACTIVE WITH SUCH AGENTS. SAID BARRIER COATING ADAPTED TO PREVENT THE REACTION OF THE AGENTS WITH THE SUBSTANCE OF THE SUPPORTING FILM, SAID EMULSIFIER BEING PRESENT IN SUFFICIENT QUANTITY TO ACT AS A DISPERSING AGENT FOR SAID WAXY MATERIAL, THE COMPOSITE FILM BEING ADAPTED TO DISPERSE IN WATER AT A TEMPERATURE IN THE RANGE OF FROM 68*F. TO 212*F.

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