DE2318336A1 - METHOD OF APPLYING MICROCAPSULES TO TISSUE AND PRODUCTS CONTAINED THEREOF - Google Patents

Description

1) Eurand SpΑ. , Cinisello Balsamo , Prov. Milan (Ital.)

2) Ignazio de Feiice ,

Cassano Magnaqo, Varese Province (Italy)

Method for applying microcapsules to tissue

and products received

The present invention relates to a method for applying microcapsules to tissue and the thereby obtained products, i.e. on tissue with applied microcapsules.

It is known that the manufacture of microcapsules is a technique based on the phenomenon of coacervation and allows closed capsules of microscopic size to be made, which have an internal phase contained, released when cutting the outer wall of the capsule or by slowly penetrating the wall will.

It has now been found that it is possible to apply microcapsules to tissue to make this particular special To give features that emphasize the qualities of the product. A practical embodiment of the process

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according to the present invention, which is of particular economic interest, is application from such microcapsules to tissue which contain fragrances, perfumes, fragrances and essences.

The term "fabric" refers to substances natural, of artificial and synthetic origin and textile products for which it is particularly advantageous Applying microcapsules with perfumed substances, such as tapes, linings for clothing, Handkerchiefs, scarves, ties, bra straps, textile fabrics and curtains for interior decoration, Divan and armchair covers, bed covers, hat trimmings, sheets, pillow cases and other household linen, dolls and Marionette dresses, etc. However, these examples are not intended to limit the invention.

The microcapsules are produced by one of the known technical processes in this field, such as, for example in German patents 1 l4l 256 and 1 245 320 are described.

These microcapsules are mixed into a suitable finishing bath, which is suitable for treating the fabric, on which they are to be applied, and then the mixture thus obtained is suitably applied to the fabric applied, such as by dipping the fabric in the bath, brushing on, splashing on, inflating, etc, preferably using the usual machines for treating fabrics such as finishing machines and Impregnation and pressing devices, which are commonly referred to as wringers, poulards, etc.

Some specific examples of the production of microcapsules, which contain fragrances and essences and themselves suitable for application to tissue will now be described in detail, as well as specific examples

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for the production of finishing baths to which the microcapsules are added, and finally examples for applying the mixture obtained in this way to fabric, in particular for applying it to ribbons and linings.

example 1

An aqueous solution of gum arabic is prepared by dissolving 55.5 g of said gum in 50 ml Water and keep the solution at 45 C. A second Solution of pig skin gelatin with an isoelectric Point at pH 9 is established by dissolving 55.5 g of the gelatin in 500 ml of water and holding the solution up 45 ° C. 80 g of lavender essence is in the gelatin solution emulsified. The emulsion thus obtained and the solution of gum arabic are mixed together and the temperature is adjusted the mixture is kept one degree above the gelatin's gelling point.

The mixture obtained is diluted with 4,000 g of water which has been heated ^{to 45 ° C. beforehand.} 32 g of a 5% strength aqueous solution of a copolymer obtained by condensing maleic anhydride and methyl vinyl ether are then added to the aqueous mixture.

Up to this point the mixture to a pH of 9 or higher pH value is maintained and the temperature is .Approximately 45 ⁰ C. Thereafter, the pH is by the addition of a 20 £ aqueous solution of acetic acid 6 humiliated.

The discrete oil droplets are now individually in the liquid State covered by a membrane. The pH of the

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The dispersion is reduced to 4.2 by adding a 20% aqueous acetic acid solution while stirring continuously.

This decrease in pH causes the part of the coacervate to precipitate that is not precipitated at pH 6 became. Then the temperature of the dispersion is lowered in order to cause the membrane to gel, and at the same time an aqueous solution of formaldehyde is added to remove that which has precipitated around the oil droplets To make coacervate insoluble.

For the abovementioned amounts, 10 ml of an aqueous solution containing 38 percent by weight of formaldehyde are added.

After the addition of formaldehyde, the pH value is immediately increased to 9 to 10 in order to reduce the hardening effect of the Aldehyde to accelerate the gelatin.

The aqueous solution is further stirred for several hours and finally become filled with lavender essence Obtain microcapsules that are suitable for application to tissue.

Example 2

A gelatin solution is prepared by dissolving 12 g of gelatin having an isoelectric point at pH 8 in 1,200 g of water of 55 C. If necessary, the solution is made by adding a 20 $ aqueous Solution of sodium hydroxide brought to pH 9.

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50 g of spruce needle oil are poured into the gelatin solution while stirring and the conditions are chosen so that that droplets with an average diameter of .30 microns are obtained.

With continued stirring, the solution on a Temperature of 55 ° C is maintained, 100 g of an aqueous solution with 20 percent by weight of a copolymer added which was obtained by condensation of maleic anhydride and polyethylene and a molecular weight has from 1,000 to 2,000.

In order to obtain the first deposition of the coacervate onto the oil droplets, the pH of the dispersion is h by addition of an aqueous solution containing 10 weight percent acetic acid to the value taken. 8

To this dispersion, which contains partially covered liquid droplets, such an amount becomes an aqueous one Solution with 20 percent by weight sodium hydroxide added that the pH is increased to 5.5.

Then 50 g of an aqueous solution with 2 percent by weight a copolymer of maleic anhydride-polyethylene with a molecular weight of 60,000 to 70,000 and at the same time the pH of the dispersion reduced to 4.6 by adding a 10% aqueous acetic acid solution. This causes complete precipitation of the remaining coacervate around the dispersed oil droplets.

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Thereafter, the temperature of the dispersion is lowered by the membrane to gel, and at the same time becomes an aqueous. Solution of formaldehyde added to make the coacervate insoluble close.

For the above amounts, 2.5 ml of an aqueous Solution with 38 percent by weight formaldehyde added.

Immediately after the addition of formaldehyde, the pH value is increased to 9 to 10 in order to prevent the hardening effect of the aldehyde to accelerate the gelatin.

The aqueous solution is stirred for several hours and finally microcapsules are obtained, which with Are filled with spruce needle oil and are suitable for application to tissue.

Example 3

A finishing bath for ribbons is made according to the following recipe:

Strength 3 kg

Melamine resin (Icefix from Icep, Italy) 10 kg Dextrin (Detrosil from Barzaghi, Italy) 7 kg Resintex strong (modified formaldehyde) 10 kg Sufficient catalyst (ammonium sulphate)

Water . 100 1

With a conventional stirrer, 50 parts of this Finishing bath and 50 parts of a suspension of microcapsules, prepared according to Examples 1 or 2, mixed and thereby obtain a bath mixture which is suitable

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to be applied to tapes by one of the methods mentioned above. The mixture must be applied at a temperature of about 35 to HO ° C and a tape with a width of 150 cm takes up about 100 liters over a length of 2,000 m.

Example 4

at HO% 0, 5 G kg at 15 % 0, 5 kg 100 5 kg

A finishing bath for lining materials is made according to the following recipe:

Melamine resin (Teefix from Icep, Italy)

) Anti-slip agents and fabric protectants (dispersed silica)

Plasticizer (soap)

Sufficient water up to

With a usual stirring device 5 kg of this Appreturbades and 7 _S5 kg of the suspension of microcapsules prepared according to Example 1 or 2 _f mixed 1 kg of a suitable binder such as polyvinyl alcohol is dissolved in the mixture or dispersed, wherein a bath mixture is obtained that is suitable for being applied to lining materials in one of the devices mentioned. The mixture must be applied at a temperature between 25 and 35 ° C and the lining materials absorb 30 to 50 liters per 1,000 m length, if the parts are 140 cm wide.

Although in Examples 3 and 4 the ratio between the finishing bath and the suspension of microcapsules is about 1: 1, this ratio can be within a wide range can be varied, from 1: 0.5 to 1:50, depending on the composition of the initial bath.

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As already mentioned, the examples represent only a few embodiments of the invention. The microcapsules can be made by any of the methods known in this particular art and as sizing baths all known compositions which are customary in the treatment of fabrics can be used.

10 claims

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Claims (10)

Patent claims: ^! 1.) A method for applying microcapsules to tissue, characterized in that to-. next microcapsules are produced with an outer shell which is compatible with the finishes and substances, and an inner liquid phase that a finish bath is produced that is suitable for the fabric to which the finish is to be applied, that a suspension of these microcapsules is mixed with the finishing bath and that the mixture thus obtained is applied to the fabric. 2.) The method according to claim 1, characterized in that a mixing ratio between the finishing bath and the Suspension of microcapsules in the range of 1: 0.5 to 1:50 is used. 3 ·) Method according to claim 2, characterized in that a mixing ratio of about 1: 1 is used. h.) Process according to one or more of the preceding claims, characterized in that a suitable binder is dispersed or dissolved in the mixture. 5) Method according to one or more of the preceding claims, characterized in that the inner phase of the microcapsules is a fragrance, a perfume, an odorant or an essence is used. 6.) Use of microcapsules containing fragrances, perfumes, Fragrances or essences mixed with finishing baths for application to fabrics or made therefrom Items. 309842/1005 7.) Tissue j treated for the application of perfumed microcapsules according to the method according to one or more of the Claims 1 to 5 8.) Lining for clothing, treated with perfumed microcapsules, which are applied according to the process according to one or more of claims 1 to 5. 9.) Textile tapes, treated with perfumed microcapsules, which are applied according to the method according to one or more of claims 1 to 5 · 10.) Articles made from textile fabrics which are perfumed with Microcapsules are treated that have been applied by the method according to one or more of the Claims 1 to 5 30 9842/1005