In one of its more specific aspects, this invention relates to a size for wet process strand.

GTaTs-^fT_Ters ^— are employed in a wide v ^' ariety of uses, some of which involve processes in which chopped, sized glass fibers are dispersed in an aqueous solution as for example, in the production of glass mat.

One of the most important properties possessed b sized glass strands used in such wet processes is the dispersal property of the strands in the aqueous solution. The dispersal property of such strands is dependent, to a large degree, upon the size on the exterior of the strand.

One of the sizes principally used for such purposes is a size comprised of polyvinyl alcohol, a silane, and a fatty amine condensate, referred to in Examples II and III as the PVA size.

There has now been developed an improved size which is superior to the size having the above composition This inventive size is superior in that it results in improved urea-formaldehyde bonded mat tensile strength, ha decreased foaming tendencies, is easier to prepare, is les expensive, its dispersion quality is much less affected by drying and the sized strand, during drying, is less tacky.

BACKGROUND ART The art is replete with sizes for glass strands,

but no art has been found to either anticipate or make obvious the size composition of this invention.

DISCLOSURE OF INVENTION

The size of this invention comprises a fatty acid amide, hydroxyethyl cellulose and a biocide.

The size will contain a quaternary fatty acid amide in an amount within the range of from about 0.05 to about 0.5 weight percent. In the preferred embodiment, the amide will be contained in an amount of about 0.15 weight percent. Particularly suitable as the quaternary fatty acid amide is Cartaflex PL as available from Sandoz Colors and Chemicals, Atlanta, Georgia. This material has an activity of 90%, a pH (4£ Solution) of 5-6 and a specific gravity (25°C) of 0.97, and a weight average molecular weight of about 1100. Another material which can be used as the fatty acid amide is Cartaflex AL, available from the same company.

The quaternary fatty acid amide is a particularly important aspect of this invention. It must meet the necessary cationic properties and limited solubility to aid in the dispersion of the glass fibers and promote good bond formation between the U.F. binder and the glass fiber surface _*

The size will contain hydroxyethyl cellulose in an amount up to about 1 weight percent, perferably in an amount of about 0.5 weight percent.

Particularly suitable as the hydroxyethyl cellulose is Cellosize QP-40-H available from Union Carbide Chemicals and Plastics, South Charleston, West Virginia. This material has a viscosity (2% solπ. Broo field, LVT No. 1 spindle at 30 RPM) of 113 to 145 cps at 25°C and a water insolubles of 0.4 weight percent and a pK (2* soln.) of 6-7.

The water soluble polymer which can be included in the size improves the cleanliness in forming, gives better moisture control of the product as a means of obtaining improved packing densities and aids the

dispersion quality in particular for high levels of the dispersant in the size.

The size will contain a biocide in an amount up to about 0.4 weight percent, perferably in an amount of about 0.05 to about 0.2 weight percent.

One suitable biocide is l,2- ibromo-2,4- dicyanobutane, known as Tektamer 38, available from Merck Chemical, Rahway, New Jersey. If this materiaal is used, it is preferably used in an amount of about 0.05 weight percent.

Another suitable biocide is Nuosept 95 as available from Tenneco, Piscataway, New Jersey. If this material is used, it is preferably used in an amount of about 0.20 weight percent.

BEST MODE OF CARRYING OUT INVENTION

The size of this invention is easily formulated as follows:

EXAMPLE I

The composition of this size formulation is as follows:

Weight % Gtπs./Liter

(as received)

Hydroxyethyl cellulose 0.50 4.94

Fatty Acid Amide 0.15 1.49

1,2-dibromo-2,4-dicyanobutane 0.05 0.48

Distilled Water 99.30 Bal.

A cellulose premix is prepared by adding 2,271 liters of water to the main mix tank and slowly dispersing the cellulose therein while the water is at 38 C. After the addition to the water, the composite is stirred for 30 minutes or until the mix becomes clear and free of particles.

A fatty acid amide solution is prepared by addin the fatty acid amide to 189.2 liters of water and stirring for 15 minutes. This mixture is then added to the cellulose solution as are 189.2 liters of water used to rinse out the tank in which the amide solution is prepared.

The 1, 2 ,dibromo-2,4-dicyanobutane , or whatever

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biocide is selected for employment, is added directly to the resulting mixture and the total solution is then agitated for one hour, or until uniformity of solution is attained.

Thereafter, an amount of water sufficient to make 3,785 liters of size _* or to give a desired solids content within the range of 0.60-0.7, is added to the solution, and the total composite is stirred for one-quarter hour after which it is suitable for use.

The size prepared as above is applied in the usual manner employing the usual size applicators, the size being employed in forming.

The strand coated with the size of this invention results in strand having 2G to 30 percent hig.her tensile strength than that realized with the previously described size containing fatty amide condensate, as shown by the following data for mats weighing two pounds per hundred square feet and having a urea-formaldehyde binder on the mat.

EXAMPLE II Size Average Tensile Strength

Designation (20% L.Q.p q. /Sq.Cm.

PVA Size 1.6

Invention Size 2.1

Invention S ze 1.8

In a similar manner, wet process mats produced from glass employing the size of this invention show superior properties as shown by the following data:

EXAMPLE III

Mat Properties, Urea-Formaldehyde Binder

Strand Basis Weight Tensile Disper

Sol ds (Gms. /Sq.Cm.) LOI(X) Kg./Sq.Cm.

( 20% LQ I R ati n P VA Si ze 0. 22% C.975 20.9 1. 43 Goo

0. 95 20.4 1 . 53 Goo

0. 93 22. 7 1. 60 Good

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St rand Basis Weight Teπsi 1 e Di sp S o l ds (Gms. /Sq.Cm.) L0I(%) Kg./Sq. Cm. (20% LOI Rat

I nvent i o n 0. 08% 1.01 19.1 1.68 F 0.87 19.7 2.67 G 0.91 24.2 2.02 G

While it can be seen from the above data that in one instance the dispersal rating of the inventive size was slightly less than that of the PVA size, in all instances the tensile strengths of the mat were definitely superior and superior in amounts from about 17 to about 86 percent

It will seem from the foregoing that various modifications can be made to this invention. Such, however, are considered within the scope of the invention.

INDUSTRIAL APPLICABILITY

This invention is empTo"ya ^~ b e in glass fiber production.

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