CA1203931A - Color concentrates for thermoplastic polymeric materials - Google Patents

Abstract

TITLE

COLOR CONCENTRATES FOR THERMOPLASTIC POLYMERIC MATERIALS

ABSTRACT OF THE DISCLOSURE

A color concentrate for coloring thermoplastic polymeric materials, which is prepared from a blend of a water - or organic solvent-dispersible polymer and a heat-stable, chemically-inert coloring agent selected from water-soluble dyes, organic-soluble dyes, polymer-soluble dyes, and pigments, from which blend any solvent present during processing is subsequently removed.

Description

BACKGROUND OF THE INVENTION
. . .

Field of the Invention This invention relates generally Jo the coloring of thermoplastics. In particular, it relates to the coloring of thermoplastics by the incorporation of color concentrates therein.

Prio The coloring of thermoplastic axticles by incorpora-tion of pigments introduced as color concentrates is well known.
Likewise, the coloring vf synthetic thermoplastic fibers by absorption of dye from solution is also a common procedure.
However, coloring of fibrous materials through the use of color concentrates is a less common practice. The reasons for this are many fold. It i5 imperative that the degree of dispersion of pigmentary particles in the concentrate be very high so that the spinning process will not be interrupted. On the other hand, preparation of masterbat~hes of dye concentrate,which would not have such a dispersion problem,by a chip dyeing procedure is complicated and expensive. Furthermore, the majority of color concentrates :
available today contain vehicles which are not totally compatible with, for instance, nylon, since nylon is one of the fibers which is less commonly colored by the addition of color concentrates.

Descrihed here is the preparation of pigment or dye concentrates in vehicles which are compatible with common giber-worming thermop1astic materials, in particular nylon. The pro-cedure is simple and very flexible. It can be used to prepa~econcentrates of pigments or water - or solvent - soluDle dyes,starting from dry colorant powders or from ~resscakes or aqueous or solvent dispersions. The concentrates can be used to color thermoplastic '' ., 1.

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materials using blending techni.ques or melt injection of con-centrzte into polymer streams The degree of dispersion is very good, so the concentrates can be used to color fibrous as well as more dimensionally uniform objects.

Advantages of the instant system over those descried in the priox art are a result of the advantages of employing a polymer which is soluble in water and/or in organic solvents:
A.) Water Pigments and dyes are precipitated from aqueous -reaction mixtures during manufacture. Pigments are very finely divided at this point. Subse-quent drying agglomerates pigment,and this is undesirable. Having a polymer which is watex soluble allows for easy incorporation of pigment }5 into polymer by mixing polymer solution and pigment dispersion and drying. Water soluble dyes can also be incorporated with no dispersion problem whatsoever and with very high color yields B.) Organic Solvent There are classes of dyes which are very soluble in certain oXganic solYents. Having a polymer soluble in these polar organic solvents enables one to make high concentration concentrates with no dispersion problem and with very high color yields.

Statement of Closest Known Art _ l U. S. lpll9,960. The essence of this process is a transfer of pigment from aqueous to "oil" phase. This is a three phase process - solid aqueous and oil. The oil and the aqueous phase remain as two distinct liquids. The resent process is two

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phase - solid and one liquid. No surfactants are used. There is no concern about incomplete transfer of pigment, so Jo pigment is lost. There is no concern about partial miscibility of oil in water thus resulting in loss of some of the oil phase and contamination of the water. All of the instant polymer is recovered, and any water present i5 removed by d2yins.

Another advantage of the present system is that a thermoplastic color concentxate can be made with else from process performed completely at room temperature. If the process of the reference is done at room temperature, it is necessary that the oil phase be a liquid, and thus the resulting colored product is not suited for handling using conventional plastic extrusion equipment. If the oil phase is a thermoplastic, : then the process must be carried out at elevated temperatures.
15 This is undesirable and also preser.ts problems of miscibility of the different phases, because of vi.scosity d.ifferences and too rapid drying of the aqueous phase.

Moreover, slnce the lnstant polymers are soluble in aqueous and polar organic solvents, one can incorporate dyes, both ~:20 water soluble and solvent soluble, into such polymers at room temperature without going through a phase transfer process.

The degree of dispersion achieved in a solid concentrate in the process of the reference is usually limited to ; the degree of dispersion originally present in the presscake.
2~ In the present invention, it is a simple matter to disperse the colorant, either in pure solvent or in the polymer solution or aispersion, to any desired degree of dispersion.

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2. U.S. 3,360,49'7~ This reference uses a phase transfer process. However, wince the final phase thereof is hydrophobic and is not soluble in water, a preliminary phase transfer step i required in order to transfer pigment from aqueous to hydrophobic phase. Complicated surfactants are needed. This hydrophobic dispersion is then combined with a solution of polymer in a hydrophobic solvent. In an embodiment of the present system, polymer is added directly to the aqueous dispersion. This simplifies matters greatly. No preliminary phase transfer step is necessary and no phase transfer surfactants are needed. The problems of incomplete transfer and other problems associated with phase transfer as mentioned above ore eliminated. The referenced system would have utility with solvent soluble dyes, but transfer of colorant from aqueous phase to "oil" phase is still required; whereas the present system is a single liquid phase system.

SUMMARY OF THE P:RE5ENT INVENTION

Difficulties resulting from the utilization of prior art processes and compositions are obviated by the provision of a color concentrate according to the present invention. This color concentrate is a blend of two essential components, advantageously a fluid - phase blend, from which blend any solvent present during processing is subsequently removed The firs component is a water - dispersible or organic solvent -dispersible polymer which is capable of being:

(1) utilized in the preparation of a 1 - 95%
solution or dispersion;
) recovered from a 1 - 95% solution ox dispersion thereof at a temperature which will not cause substantial volatilization Dr degradation thereof;
l (3) fused at standard thermoplastic processing temperatures; that is, between about 130 and 350C;

(4) melted with a thermoplastic material to be colored without s~bstantiai degradation or reaction and without any visible separation on a microscopic scale; and . (~) utilized as a wetting agent for pigments.
-The second component is a heat - stable, chemically inert coloring agent selected from the group consisting of water - soluble dyes, : organic - soluble dyes, polymer - soluble dyes,and pigments.

Especially advantageous results are achieved if the first component of the concentrate is selected from the yroup consisting of water -dispersible or organic solvent - dispersible polyamides; water -3~L

dispersible or organic solvent: - dispersible polyester; water -dispersible or organic solvent - dispersible vinyl polymers or copolymers; and water - dispersible or organic solvent -dispersible alkylene oxide polymers or copolymers. Under such conditions, very beneficial results are obtained when khe coloriny agent is a pigment, which is present in the color concentrate in an amount sufficient to provide from about 1 to about 70 percent by weight thereon, based on the total weight of the color concentrate. Equally beneficial results are achieved, moreover, it the coloring agent is a dye, which is present in the color concentrate in an amount sufficient to provide from about 1 to about 70 percent by weight thereof, based on the total weight ox the color concentrate.

Concentrates according to the present invention are utilized with especially advantageous results in coloring thermoplastic l polymeric materials which are employed in the production of synthetic textile fibers.

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, EXA~P _ The following examples set forth in detail various methods of preparing and utilizing color concentrates according to the present invention. As is understood by those of skill in the art, these examples are illustrative in nature, and should not be taken as limiting the invention in any way.

_ 176g of the water dispersible polyamide of USP 3,846,507 was combined with 704g of water. The mixture was stirred at 80C
until dispersion of the polymer was complete.

200g of Milton Davis Peacoline (copper phthalocyanine) Blue 37.7%
solids presscake was placed in a two quart stainless steel Waring blender. 80g of the aqueous polymer dispersion was added to the l blender. the mixture was blended for 25 minutes. The remaining 800g o~polymer dispersion was added it 20~g increments with approximately 10minutes blending time between increments. Microscopic examination ofthe pigment slurry at this point revealed very good wetting of the p~me~t by the vehicle and dispersion of the pigment in the vehicle.
: -2~ he slurry was then filtered through a 35mm screen pack assembly consisting of 4 jilter greens a 20 me5h, a 60 mesh, a 180 mesh, and : : : .
:: a 325 mesh (40 micron) .screen. One filter change was required.
The slurry was then collected in a shallow pan and dried under vacuum at 6CC until hard (approximately 2 days). This yielded a color concentratP containing 30~ pigment.
:: `:
: -One part of the solid color concentrate was blended with 79 parts of uncoIored nylon-6 polymer containing 0.03~ titanium dioxide.

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This mixture was extruded into yaxn comprised of fiber of 52 denier/filament at a temperature of 255C and a spinning speed of 330 meter/minute, This fiber was then drawtwisted at a draw ratio 3.4 to 1 at a speed of 400 meters/munute with a twist of

5 . O . 25 turns/inch to yield yarn containing drawn fiber of approximately 16 denier~filan~ent. Deeply eolored blue fiber containing l pisment was obtained.

The procedure of Example 1 was repeated except that the Hilton Das~is Peacoline Blue 37 . 7Pb solids presscake was replaced my duPont Monastral Green G 53 . 4~ high-solids presscake. Deeply colored green f.iber containing 1% copper phthalocyanine green pigment was obtained.

15 The procedure of Example 1 was repeated except that the Hilton Davis Peacoline Blue presscake was replaced by BASF Paliofast LBGD-K 46. 6% solids copper phthalocyanine blue presscake.
Deeply colored blue fiber containing 1% pigment was obtained.

20 The procedure of Example i was replated except that Hilton Davis Peacoline Blue presscake W2S replaced by duPont Monastral Green G GT-751-D dry powder copper phthalocyanine pigment and dis-persion was accomplished ultrasonically using an ultrasonic dispersing device manufactured by 50nic Corp. tStratf~rd, CT. ) to produce a concentrate containing 25~ pigment The concentrate was used as before to produce deeply colored green giber. .

* Trademark .I!L~o~s~

EXAMPLE S

The procedure of Example 1 was repeated except that Hilton DaYis Peacoline Blue presscake was replaced by BASF Luconyl Red 387, a 30 percent dispersion of pigment Red 123 in water, and no high speed mixing was employed. One part of the 30 percent concentrate was blended with 29 parts of uncolored nylon

6 polymer containing O percept titanium dioxide, and the procedure of Example 1 was ollowed to produce deeply-c~lored red fiber containing l piyment.

320g of BASF Neozapsn Yellow R ~olvent-soluble dye was dispersed in 1067ml of anhydrous ~ethan~l. The colorant dispersed (except or a small amount of residual insolubles) almost instantly end very little stirring was required.
.
l 480g of the polyamide of USP 3,846,507 was combined with 2400g of a solvent which consisted ox 300g of water and 2100g of methanolO the mixture was stirred at 50~C until dispersion of the polymer was complete.

The 17~ polymer dispersion was added slowly to the methan~lic dispersion of ~eozapon R wlth stirring. The resulting dispersion W25 then filtered through the filter pack assembly described in Example 1. Almost no pressure build-up on the screen pack was recorded. the dispersion was then placedin a shallow pan and dried : under vacuum a 5006QC. 670g of a 40% color c~nGen~rate w s obtained.

One part of the slid color concentxate was blel,~ed ~i~h 39 parts of uncolored nylon-6.polymer containing 0~03~ titanium dioxide.
The mixture was extruded into fiber as in Example 1 to obtain deeply colored gold~fi giber containing 1% color~n~.
* Trademark to 9-,~

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`XAMPLE_7 6.5g of the nylon 801uble colorallt Fil~mid Red 841 (Ciba Geigy) was combined with lOOg of a 204 aqueoug ~i~persion of the polyamide of USP 3,846,507. The mixture was heated to 50~C and agitated overnight. The mixture was then xemoved from the heat and left undisturbed until the colorant completely dispersed. The dispersion was filtered through the ilter pack assembly described in Example 1. It was estimated that 34 of the original amount of colorant was dep~sïted on the screen. The disperslon was dried in a vacuum oxen at approximately 60C to obtain a color concentxate ~ont~ining 25~ pigment.

One part of the solid color concentrate was blended with 24 parts of uncolored nylon-6 polymer containing 0.03% titanium dioxide.
The mixture was extruZed into yarn comprised of fiber of 52 denier/
filament at a temperature of 2~5~C and a spinning speed of 330 miens minute. The yarn way then dra~rt~isted Jo yield deeply colored maroon fiber ox 12 denier/filament.

.
The procedure oP Example 7 was repeated except that Filamid Red 841 was replaced by ~ilamid Yellow 2732. Deeply coloxed golden fiber was obtained.

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The proc~durç of Example 1 was repeated except that American Roechst pigment Nov~perm Rev BL was used,and the pigment was oompound2d directly into the molten polyamide of USP 3,846,507 using a high shear process rather than dispersed into an aqueous dispexsion of the polymer using high speed mixing process. A
color concentrate containing 25% pigmer.~ was obtained.
* Trademark 10 .
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i., I, .

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One part ox this solid color c:oncentrate was blended with 24 parts of uncolored nylon-6 polymer containing 0.~3% titanium dioxide and spun and drawtwisted into yarn as described in Example 1.
Deeply colored red fiber containing 1% pigment was obtained.

One part of the color concentrate of Example 2 was blended with 29 parts ox uncolored poly(ethylene terephthalate) containing 0.33% titanium dioxide and spun into yarn comprised of fiber of 52 denier/filament at a temperature of 3~0& and a spinning speed of 330 meters/mi~ute. The yarn was drawtwisted as in Example 1 to yield .deeply colored green fiber of.l6 denier/filament~containing 1% pigmP~t.

463g of Hilton Davis Peacoline (copper phthalocyanine) Blue 37.7 solids presscake was placed in a two quart stainless steel Waring lS blendex. 715g of a 28~5% dispersion of the water-dispersible polyester of USP 4,098,741 was added to the blender and the mixture was blended for one hour. on additional 715g of the polyester dispersion was added to the mixture and blending was continued for another hour. Microscopic examination of the pigment slurry at :: 20 this point revealed good wetting of the pigment by the chicle and good dispersion of the pigment in the vehicle.

The slurry was then filtered through the 3~mm screen pack describea in Example 1. No filter changes were required. The slurry was collected in a hallow pan and dried under vacuum at 60C until ~5 hard. This yielded a color concentrate containing 30% pigment.

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One part of the solid color concentrate was blended with 29 parts uncolored nylon-6 polymer containing 0.03~ titanium dioxide. The mixture was extruded into yarn comprised of fiber of 52 denier/
filament at a temperature of 255 C and a spinning speed of 330 meters/minute. This yarn was then drawtwisted into fiber of 12 denier/filament to yield deeply colored blue fiber containing 1%
pigment.

xample 12 One part of the color concentrate of Example 11 was blended with 29 parts of uncolored poly[ethylene terephthalate) containing 0.33%
titanium dioxide and spun into yarn comprised of fiber of 52 denier/
filament at a temperature of 300C and a spinning speed of 330 meters/minute. The yaxn was drawtwisted to yield fiber of 16 denier/
filament. Deeply colored blue fiber containing l pigment was obtained.
l Example 13 one part of the color concentrate of Example 11 was blended with 29 parts of the uncolored poly(ethylene terephthalate) containing no titanium dioxide and spun into yarn comprised of fiber of 52 denier/
filament at a temperature of 300 C and a spinning speed of 330 meters/minute.
The yarn was drawtwisted to yield fiber of 12 denier/filament.
Deeply colored blue fiber containing 1% pigment was obtained.
Example 14 142g of duPont ,~onastral Green G GT-751-D dry powder copper phthalocyanin2 pigment was placed in a two quart stainless steel Waring blender 750g of a 28.5% dispersion of the water dispersible polyester ox USP 4,098,741 was added to the blender and the mixture was blended for 1 hour. An additional 750g of ~2~3~3~1L
polymer dispersion was added and blending was continued for an additional hour. Microscopic examination of the pigm~;lt slurry x~vealed good jetting of~t~e pigment my the vehicle and good do spors on of tl e pigment irl the vehicle .
The slurry was filtered through the screen pack assembly described in Example 1. One filter change was made during the filtering.
The slurry was collected in a shallow pan and dried in a vacuum oven at 50C until hard. A color concentra e containing 25%
pigment was obtained.

One paxt of the solid dolor concentrAte was blended with 24 parts sf uncolored polyethylene terephthalate) containing 0.33% titanium dioxide and spun into yarn comprised of fiber of 52 denier/filament ¦
at a temperature of 300C and at a spinning speed of 330 meters/
minute. The yarn was drawtwisted as in Example 1 to yield a fiber of 16 denier/filament~ Deeply colored green fiber ~nta~ pigment was obtained.

4ûOg of the sodium salt of a low molecular weight vir.yl copolymex consisting of the monomers ~-sulfoethyl methacrylate and ethyl acrylate in a ratio of 1 sul~onated monomer to every 4 non-sul-fonated monomers was combined with 400g of water. The polymer dissolve rapidly to yield a clear yellow liquid which appeared to be more of a true polymer solution than a dispersion as was obtained in the preYiOUS example,s.

454.7g of Hilton Dais Peacoline (copper phthalocyanine) Blue 37.7% solids presscake was placed in a two quart stainless steel Waring blender. 400g of the polymer solution was added to the blender and the mixture was blended for 45 minutes. The remaining polymer solution was added and the mixture was blended ~sr an 30 additional 45 minutes.

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The pigment slurry was then filtered through the screen pack assembly described in Example 1 with one filker change required.
The material was collected in a stainless steel beaker and dried under vacuum at 40-70C until hard. A color concentrate contain-i~g 304 pigment was obtained.

One part of the solid color concentrate was blended with 29 parts of uncolored nylon-6 polymer containing 0.03~ titanium dioxide.
This mixture was extruded into yarn comprised of fibex of 52 denier filament at a temperature of 255C and a spinning speed of 330 meters/minute.
A sulfur-like odor was noticed during spinning and extrusion of uncolored vinyl polymer with nylon-6 causing a slight discoloration of the nylon. Also some crocking of the blue colorant onto guides on the fiber takeup machine was noticed. The spun yarn was draw-twisted as described in Example 1 to yield fiber of 16 denier/filament. Deeply colored blue fiber containing 1 pigment was obtained.

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____ 400 g of a primarily poly (alkylene oxide) polymer such as those disclosed in U.S. 4,093,676 or U.S. 4,02g,694, was combined with 2266g of water and the mixture was heated and stirred until the polymer became dispersed homogeneously in the water solvent.
The mixture was blended in a Waring blender briefly to insuxe homogeneity.

606g of Hilton Davis Peacoline (copper phthalocyanine) glue 37.7% solids presscake was placed in a two quart stainless steel Waring blender. 500g of the polymer dispersion was added to the blender and the mixture was blended for 1 hour. The remaining 2166 g of polymer dispersion were added to the pigment slurry in four equal increments and the mixture was blended for ~0 minutes after each addition. MicrosCOpic examination of the pigment slurry revealed good wetting of the pigment by the vehicle and good dispersion of the pigment in the vehicle.

The pigment slurry was filtered through the filter pack assembly described in Example 1. Three filter changes were required.
The slurry was collected in a shallow pan and dried under vacuum at 50-60C until dry. A color concentrate containing 36%
pigment was obtained.

One part of the solid color concentrate was hlended with 35 parts of uncolored ~ylon-6 polymer containing 0.03% titanium dioxide.
The mixture was extruded into yarn comprised of fiber of 52 denier/
filament at a temperature of 255C and a spinning speed of 330 meters/minute. This yarn was then drawtwisted as in Example 1 -to yield deeply colored blue fiber of 16 denier/filament.

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EXAMPLE_17 40.2g of duPont Monastxal Green G GT-751-D dry powder copper phthalocyanine pigment, 6.0g of the surfactant, o It C13~27-C-0 (CH2CH~O)13 and 160.0g of demineralized water were charged into a two quart stainless steel Waring blender. The mixture was blended for 30 minutes and then filtered through the filter assembly described in Example l.

75g of nylon-6 polymer containing no titanium dioxide was dissolved in 300g of formic acid at a temperature near the boiling point of formic acid.

The pigment slurry was heated to 90 C and added slowly to the hot polymer solution. The resulting slurry was collected in a shallow pan and allowed to sit undisturbed for 2 days Upon cooling, a solid material was obtained. This solid material was broken into smaller pieces and placed in a vacuum oven at 60C until dry. A color concentrate containing 22% pigment was obtained.

One part of the solid color concentrate was blended with 21 parts of uncolored nylon-6 polymer containing 0.03% titanium dioxide. The mixture was extruded into yarn compr~ed of fiber of 52 denier filament at a temperature o ~55~C and a spinning speed of 33Q
meters/minute. this yarn was then drawtwisted as in Example l to yield deeply colored green fiber of 16 ~enier~filament.

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194g of the water dispersible polyamide of USP 3,846,507 was combined with 775g of water. The mixture was stirred at 80C
until dispersion of the polymer was complete.

83g of Ciba-Geigy Nylaspin Scarlet G heat stable, water soluble dye was added to the aqueous polymer dispersion. As the mixture was stirred, the dye particles dissolved and went into solution forming a deep maroon-colored liquid. The viscosity of the polymer dispersion increased as the dye particles dissolved. Heating to 40~C accelerated the dissolution process.

Microscopic examination of the dye solution revealed a deeply and uniformly colored liquid containing a small number of insoluble particles, the particles being present in the original ; dye powder.

The solution/dispersion was filtered through the filter pack assembly described in Example 1 and dried in a vacuum oven at 60C to obtain a thermoplastic color concentrate containing 30%
colorant.

One part of the solid color concentrate was blended with 29 parts of uncolored nylon-6 poIymer containing 0.03% titanium dioxide. The more was extruded ho yarn ccmprised of fiber of 52 denier/
filament at a temperature of 255 C and a spinning speed of 330 meters/minute. This yarn was then drawtwisted as in Example 1 to yield drawn fiber of approximately 16 denier/filament.

Deeply colored brownish-orange fiber con~ainin~ l colorant was obtained.

3~3~a The present invention has been described in detail with respect to certain preferred embodiments thereof. As is understood by those of skill in the art, variations and modifications in this detail may be effected without any departure from the spirit and scope of the present invention, as defined in the hereto-appended claims.

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Claims (7)

I CLAIM

1. A color concentrate for coloring thermo-plastic polymeric materials, the concentrate comprising a blend of the following two essential components, from which blend any solvent present during processing is subsequently removed:
(A) A water - or polar organic solvent -dispersible polycondensation or addition polymer polymerized from condensable or unsaturated monomers containing functional groups capable of solubilizing or dispersing the polymer in water or in polar organic solvents, and which is capable of being:
(1) utilized in the preparation of 1-95 solution or dispersion;
(2) recovered from a 1-95% solution or dispersion thereof at a temperature which will not cause substantial volatilization or degradation thereof;
(3) fused at a temperature between about 130 and 350°C;
(4) melted with the thermoplastic polymeric material to be colored without substantial degrada-tion or reaction and without any visible separation therefrom on a microscopic scale; and (5) utilized to wet the surface of pigments by adhesion thereto; and (B) A heat - stable, chemically - inert coloring agent selected from the group consisting of: water - soluble dyes; polar organic solvent -soluble dyes; polymer - soluble dyes; and pigments, the coloring agent causing no visible chemical reaction with the thermoplastic polymeric material to be colored or the water - or polar organic solvent - dispersible polycondensation or addition polymer.

2. The color concentrate of claim 1, wherein component A is selected from the group consisting of: water - or polar organic solvent - dispersible polyamides; water - or polar organic solvent -dispersible polyesters; water - or polar organic solvent - dispersible vinyl polymers or copolymers;
and water - or polar organic solvent - dispersible alkylene oxide polymers or copolymers.

3. The color concentrate of claim 2, wherein the coloring agent is a pigment, which is present in the color concentrate in an amount sufficient to provide from about 1 to about 70 percent by weight thereof, based on the total weight of the color concentrate.

4. The color concentrate of claim 2, wherein the coloring agent is a dye, which is present in the color concentrate in an amount sufficient to provide from about 1 to about 70 percent by weight thereof, based on the total weight of the color concentrate.

5. The color concentrate of claim 2, wherein the functional groups capable of solubilizing or dispersing component A in water or in polar organic solvents are selected from the group consisting of sulfonate groups, phosphate groups, and polyglycol groups.

6. The color concentrate of claim 1, wherein the thermoplastic polymeric material to be colored is nylon-6.

7. The color concentrate of claim 1, wherein the thermoplastic polymeric material to be colored is poly (ethylene terephthalate).