US3633974A

US3633974A - Method of making tufted constructions

Info

Publication number: US3633974A
Application number: US20624A
Authority: US
Inventors: John C Lewis Jr
Original assignee: TUCEL INDUSTRIES
Current assignee: TUCEL INDUSTRIES; TUCEL INDUSTRIES Inc
Priority date: 1970-03-18
Filing date: 1970-03-18
Publication date: 1972-01-11
Anticipated expiration: 1989-01-11
Also published as: GB1276760A; DE2109972A1

Abstract

This invention, consisting of a new method for making brushes, allows tufted brushes and tufted mat components to be manufactured having pretrimmed synthetic filament tufts supported by thin foamed substrates. The method comprises first picking synthetic filament tufts and subsequently assembling the tufts in a predetermined tuft pattern. Secondly, the tufts are then attached to a weblike support. Third, the supported tufts are then set in a foam composition whereby the base of each tuft is surrounded and supported by foam.

Description

United States Patent Inventor John C. Lewis, Jr.

Middlebury, Vt.

Appl. No. 20,624

Filed Mar. 18, 1970 Patented Jan. 1 l, 1972 Assignee Tucel Industries, Inc.

Middlebury, Vt.

Continuation-impart of application Ser. No. 841,160, Oct. 25, 1968, now Patent No. 3,596,999, dated Aug. 3, 1971, and a continuation-impart of 800,330, Jan. 24, 1969, now Patent No. 3,604,043, dated Sept. 14, 1971. This application Mar. 18, 1970, Ser. No. 20,624

METHOD OF MAKING TUFTED CONSTRUCTIONS 12 Claims, 22 Drawing Figs.

U.S. Cl 300/21 Int. Cl A46b 3/04 Field of Search... 300/21 [56] References Cited UNITED STATES PATENTS 2,878,069 3/1959 Wessel, Jr 300/21 3,053,575 9/1962 Zeilstra 300/21 3,072,945 1/1963 Peterson. 300/21 X 3,256,546 6/1966 Schmidt 300/21 X 3,425,084 2/1969 St. Laurence et al.. 300/21 X 3,471,202 10/1969 Lewis,.lr. 300/21 X Primary ExaminerGranville Y. Custer, Jr. Attorney- LeBlanc & Shur PATENTED Jun 1 I972 sum 3 0F 4 METHOD OF MAKING TUFTED CONSTRUCTIONS This application is a continuation-in-part of my copending application Ser. No. 841,160, filed Oct. 25, 1968, now U.S. Pat. No. 3,596,999, issued Aug. 3, 1971; and a continuationin-part of copending application Ser. No. 800,330, filed Jan. 24, 1969, now U.S. Pat. No. 3,604,043, issued Sept. 14, 1971; both of which are divisional applications of parent application Ser. No. 578,840, filed Sept. 12, 1966, now U.S. Pat. No. 3,47 l ,202, issued Oct. 7, 1969.

This invention relates to new and useful brush-type articles and a method for producing same. More specifically, it is concerned with fabrication of tufted synthetic filament whereby said filament is supported by foamed substrates. It includes novel brush constructions and methods of manufacture.

The brush and carpet industry for many years have been limited in design due to the conventional substrates and methods employed for joining tufts of filaments to the substrates. In most instances, the filaments forming the tuft are doubled over in a U-shape and held to a somewhat thick substrate by means of a staple in the case of a brush and a cordlike rope in the case of a carpet. in both cases, the tufts are held fast by the anchoring means. Also, the method of making tufts and joining them to the substrate does not allow for multiple tuft formation.

The picking and formation of multiple tufts from synthetic filament have been described in U.S. Pat. No. 3,471,202 by Lewis, and allow pretrimmed synthetic filament tufts to be assembled from filament having a length nearly the same as the finished desired tuft. By employing the method of forming tufts in accordance with the Lewis patent, it becomes possible to construct tufted articles having this foamed substrates, i.e., l-inch tufts supported by polyurethane foam having a thickness of one-eighth inch.

It will be apparent in the discussion which follows wherein the novel constructions of this invention differ from conventional constructions and it should be apparent also that there are many economical factors to be gained by such methods of construction.

Objects and advantages of this invention will be set forth in part hereinafter and in part will be obvious herefrom, or may be learned by practice with the invention, the same being realized and attained by means of the steps, methods, combinations and improvements pointed out in the appended claims.

The invention consists in the novel steps, methods, combinations, compositions and improvements herein shown and described.

The objects of this invention will now be described. While this invention is primarily concerned with new and novel brush constructions and tufted modular components, it should be realized that the principles of this invention are attained only through the novel combination of retaining cut-to-length parallel synthetic filament and dispensing those filaments in situations wherein (1) single filament tufts are formed, (2) multiple filament tufts are formed, (3) complete tufted brushtype constructions are simultaneously formed and (4) continuous modular tufted strip-type constructions are formed. Any of these described situations can be supported by foamed substrates.

An object of this invention is to provide a tufted brush-type construction comprising pretrimmed synthetic filament tufts arranged in a tuft pattern and self-supported by a thin foamed substrate. Another object of this invention is to provide a tufted construction comprising synthetic filament tufts supported by lightweight flexible foam.

Further objects of this invention are to provide novel methods for the production of tufted constructions employing the features set forth in the foregoing objects. These objects are attained by the procedure particularly described hereinafter, as well as in my hereinabove-mentioned U.S. Pat. No. 3,471,202, which procedure comprises, in its broader aspects, joining filament tufts at their fused base by employing a substrate or connector, said substrate employed for aligning tuft formations prior to supporting said tufts in foam. The more usually preferred connectors are those of extruded thermoplastic monofilament whereby the unset fused tuft-end is brought into contact with said connector prior to cooling and then allowed to cool, providing a tuft-base secured by the monofilament. This construction is then subsequently set in foam in one of the ways designated hereinafter.

Brushes have been prepared as described in U.S. Pat. No. 2,576,546 wherein plastic filaments, i.e., nylon, have fused ends. The fused ends are set in rubber and cured until the filaments are held securely. Unlike the instant invention, tufts are not held together at their bases prior to insertion into rubber, nor are the tufts capable of being arranged in tuft formations, i.e., 48-tufted scrub brush. it should be noted that the prior constructions could not be supported in foam, nor were they, in fact, susceptible to being supported prior to being secured in the rubber. The rubber had to be supported on a core thus not allowing for self-supporting tuft formations.

in the discussion which follows, for convenience sake, the term synthetic filament applies to those synthetic monofilaments which are formed from linear thermoplastic polymers from the group consisting of polystyrene and polystyrene copolymers, polyvinyl chloride and polyvinyl chloride acetate copolymers, polyflourides, polyethylene, polypropylene, polyethylene-polypropylene copolymers, polyamides, polyimides, polyesters and polyurethane. Both oriented and unoriented monofilaments may be employed. Also, various cross-sectional shapes may be imparted to the monofilaments, such as for instance, i.e., circular, lobular, trifoil, X and Y" cross sections, triangular, polygonal, star, etc. Mixtures of synthetic monofilaments may be employed in cases where the compositions of the filaments are compatible during any fusing operations, i.e., heat-sealing. Such filaments may have suitable crimp imparted to all or some portion of their length.

The term picking as used in the specification refers to the formation of a filament tuft wherein the tuft is formed by engaging more than one cut-to-length filament by its end and removing same from a parallel disposed bundle of filaments. The picking device employed is of the type disclosed in the aforementioned U.S. Pat. No. 3,471,202.

The term substrate refers to the foamed composition surrounding the filament tufts and can be either flexible or rigid. The foam acts as the handle or back in conventional brush constructions.

As indicated above, the foam substrate of this invention is made from a polyurethane foam. The term polyurethane foam as used herein, includes both polyester-based polyurethane foam and polyetherbased polyurethane foam. Any conventional polyester based-polyurethane foam or polyether-based polyurethane foam may be employed for the substrate. As is well known, polyester-based polyurethane foams are conventionally made by reacting an organic polyisocyanate, i.e., toluene diisocyanate, with a polyester containing free hydroxyl and/or carboxyl groups, i.e., the polyester resin reacting product of ethylene glycol and adipic acid. When reacting a polyisocyanate with a hydroxy-polyester, a small amount of water is added to bring about carbon dioxide formation with polyisocyanate and the reaction is accelerated in known manner by the addition of catalysts, i.e., a tertiary amine catalyst such as triethylamine and N-methylmorphaline.

Polyether-based polyurethane foams are conventionally made in a manner similar to that described above except that in place of a polyester, a polyether is employed for the reaction with the polyisocyanate. U.S. Pat. Nos. 2,726,219, 2,8l4,606 and 3,029,209 disclosed polyurethane foam compositions that may be used as the substrate in accordance with this invention. Specific foam examples will be set forth hereinafter.

The term connector" refers to any material, for example a monofilament, which is employed for attaching tufts thereon in order to arrange and support tufts prior to foaming. The connector can be in the form of a screen knit or other similar constructions.

In the drawings:

FIG. 1 is a front view of a fiber tuft of this invention.

FIG. 2 is a front view of the tufts of this invention attached to one another at their base by a connecting means.

FIG. 3 is a bottom view of the tufts of FIG. 2.

FIG. 4 is a side cross-sectional view taken along line IVIV of FIG. 2.

FIG. 5 is a front view in cross section of the tufts of FIG. 2 supported in rigid foam.

FIG. 6 is a side cross-sectional view taken along line VIVI of FIG. 5.

FIG. 7 is a front view in cross section of the tufts of FIG. 2 supported in flexible foam.

FIG. 8 is a sectional view in cross section of the tufts of FIG. 2 being set in foam to form a foam-supported tuft construction.

FIG. 9 is a longitudinal sectional view of the foam-supported tufts as formed in FIG. 8.

FIG. 10 is a fragmentary bottom view of a group of tufts held together by a weblike means.

FIG. 11 is a side cross-sectional view of some of the tufts of FIG. 10.

FIG. 12 is a detailed fragmentary view of a mat in perspective and partly in section showing one arrangement of the tufts from FIGS. 10 and 1 1 supported in foam.

FIGS. 13-17 illustrate a method of assembling a brush employing the sections of FIG. 5. FIG. 13 is a front view of a section comprising a multiplicity of filament tufts joined together and supported by rigid foam. FIG. 14 is an end view of FIG. 13. FIG. 15 is an end view of four sections aligned side by side. FIG. 16 is an end view of a cap adapted to be placed over the aligned segments of FIG. 15 in the manner shown in end view FIG. 17 which shows a finished brush construction with the sections held by the cap.

FIG. 18 is a front view of the tufts of this invention attached to each other by polypropylene monofilament.

FIG. 19 is a fragmentary bottom view of a group of tufts as shown in FIG. 18.

FIG. 20 is a side view partially in cross section of a shoebrush from the tuft formation of FIG. 19.

FIG. 21 is an end view of the shoebrush of FIG. 20.

FIG. 22 is a fragmentary side view of a flexible continuous belt-of-tufts supported in flexible foam.

In order to describe the invention more fully, reference is now made to specific embodiments illustrated in the drawings. The invention is directed to brush making wherein tufted brushes and tufted constructions result by first forming modular tufted arrangements, said tufted arrangements comprising cut-to-length synthetic filament fused at one end and attached to adjacent tufts by means of a connector, then setting the arrangement in a foamed substrate whereby the resultant construction is self-supporting and said tufts are held securely within the foam support. Such a tuft employed for these constructions is shown in FIG. 1. The tuft of FIG. 1 is formed from cut-to-length filament 100 by picking said filament from one end and heating to fuse the opposite end portion 101 to a temperature of approximately that of the melting point of the particular type of synthetic filament employed. Most thermoplastic filaments have softening points which make them pliable and capable of fusing together under slight pressure. Consequently, as the heated ends of the filaments soften, they are brought into contact with a connecting material, i.e., polypropylene monofilament, and subsequently pressed around the connectors thus resulting in the filament tuft being supported in a weblike structure whereby the fused base end 104 of FIG. 2 of each tuft is attached to an adjacent tuft. The tufts in FIG. 2 show one such tuft construction where the base 103 is attached to an adjacent tuft 102 by means of connector 104. This construction can be likened to a string-of-pearls." The fused base 103 for purposes of illustration, is shown much larger than necessary, and does not have to extend beyond the filament in the tuft. The base 401 of FIG. 18 shows another embodiment of the fused section where the base does not extend beyond the width of the filament diameter.

In order to form a single length of self-supporting tufts as illustrated in FIGS. 5 and 6, it is necessary to first prepare a continuous length of attached synthetic tufts as shown in FIG. 2. The tufts are then brought into contact with a polyurethane foam-producing mix which, within seconds, begins to react and a foam structure results. Within a relatively short period of time, i.e., seconds, the foaming action will reach a peak or rise point, and then gel. Within another few minutes, i.e., I20 seconds, the foam substrate will be tack free and for all practical purposes, will be considered set. The tufts are, at this point, securely held and of a self-supporting nature.

To illustrate the aforedescribed procedure more specifically, the following specific example is now given:

EXAMPLE I A batch of 9 pounds per cubic foot rigid polyurethane foam was made by the following recipe (all reactants were at room temperature):

One-hundred grams of Mistafoam 850-8 urethane foam base (material manufactured by M-R Plastics and Coatings, Inc.) was blended with grams of Mistafoam 80l-H urethane foam prepolymer in an electric mixer for 60 seconds (cream time) and then poured to a depth of one-sixteenth inch onto a metal tray measuring three-eighth inches wide, 36 inches long and three-sixteenth inches deep. Immediately, a string-of-tufts" was placed into the foam composition and within 30 seconds the foaming reaction started. At the end of 120 seconds the tufts were held fast within the foam substrate. A strip of self-supporting tufts as shown in FIG. 5 resulted wherein the foam substrate supports tufts 102, the thickness of the substrate being on the order of one-eighth inches.

The invention in its broader aspects is not limited to rigid foam compositions. In order to fully describe the flexible strip of tufts as shown in FIG. 7, reference is now made to the flexible substrate 106 in FIG. 7.

EXAMPLE II A batch of 2 pounds per cubic foot flexible polyurethane foam was made by the following recipe (all reactants were at room temperature):

Fifty grams of Formez-SO (a polyester-resin) was blended with 2 grams of N-ethyl morpholine in an electric mixer for 45 seconds and then 3.6 grams of distilled water added and the mixture allowed to mix for another 30 seconds. To this resin premix, 105 grams of Nacconate 80 (80:20 mixture of 2,4 and 2,6-toluene diisocyanate) was added and mixed for approximately 10 seconds, then poured onto the same metal tray as cited in example I. Immediately after, a string-of-tufts was immersed in the premix and foaming allowed to continue. Soon after, 5-10 seconds, the foaming action started and the cell structure formed. Within 240 seconds the tufts were selfsupported in the substrate and a strip of tufts as shown in F IG. 7 resulted. The substrate portion 106 was approximately three-sixteenth inches in thickness.

While the invention is susceptible of embodiment in many different forms, there is shown now in FIGS. 8 and 9 specific embodiments with the understanding that the present disclosure is to be considered as an exemplification of the principle of the invention and is not intended in any way to limit the invention to the embodiment illustrated.

Particular attention is now given to the cylindrical brush construction and method of forming as shown in FIGS. 8 and 9. The method consists of wrapping a string-of-tufts 102 around a rigid supporting means 109 while simultaneously applying a foamed polyurethane premix from supply 108 through nozzle 107 in order that the fused ends 103 of tufts 102, said tufts attached by connector 104, can become securely held in the substrate 110. The foaming support means 109 is rotated in direction B while the tufts 102 come from direction A. As the foaming begins and cell structure takes place, substrate 110 is formed. After the foam composition is set, it is removed from support means 109 in direction C thereby resulting in a tufted cylindrical brush 11 l. The method can be carried out whereby the brush 111 is simultaneously removed during the foaming operation by allowing enough time between removal and curing of the foam. This only requires a sufficient distance between the wrapping and foaming section and the cured section of brush. Although not shown, it is possible to form an inverted cylindrical tufted unit wherein the tufts project inward.

EXAMPLE III A tufted cylindrical brush (polypropylene tufts) having a 1- inch diameter and a 3-inch brush face comprising 108 synthetic tufts having a trim length of 1 inch and a tuft diameter of three-sixteenth inches, supported in rigid polyurethane foam, was constructed in the following manner:

A batch of 9 pounds per cubic foot rigid polyurethane foam was made according to the same procedures as cited in example I. The premix was then applied in liquid form to a paper mandrel (5 inches long and having a diameter of 1 inch, the thickness being 0.050 inches) and a continuous string-oftufts was wrapped around, taking care to embed to base of the filament tufts in the foam premix. When the tufts had been wrapped, foaming started and within 120 seconds, the whole mass had set. A few more minutes and the mass was tack free. The paper core was twisted from the brush unit leaving a completely self-supporting tufted polypropylene cylindrical brush having a substrate of rigid polyurethane foam. The substrate had an average thickness of three-sixteenth inches. The excess foam was removed at each end leaving a 3-inch brush face.

It is apparent that the tufted mat construction illustrated in FIG. 12 is a complicated construction, and could not be produced by any technique other than by practicing the method disclosed in the instant invention. In addition, the invention in its broader aspect is not limited to individual tufts having a base area greater than the area of the filament comprising the tuft whereby a bead is employed to anchor the tuft. Tufts so formed in accordance with this invention can have fused base portions wherein there is no significant portion of fused area, but more important is the fact that the fused portion is held to and attached thereto an adjacent fused portion by means of a finite substance. This connector acts as an alignment means for tufts, and arrangement control and a reinforcing medium for the foam composition, and contributes to the stability of the tuft with the foam support.

More specifically, referring now to the ski mat construction of FIG. 12, the tufts 199 are supported in flexible foam 202. The tuft bases 200 are attached to each other by means of connectors 201 as shown in FIGS. 10 and 11. The connector is formed from an oriented polypropylene monofilament whose diameter is in the order of 0.025 inches.

A ski mat in FIG. 12 was made by the following example:

EXAMPLE IV A tufted arrangement consisting of polyamide synthetic filaments was produced by first picking filament at its nonworking end to form tufts, and subsequently, adfixing the heated ends to a network of polypropylene monofilament in order to produce the construction shown in FIG. 10. A premix of flexible foam was prepared according to the method cited in example II and poured onto a flat sheet of wax paper. Before foaming started, the tuft arrangement was embedded in the foam premix. Immediately afterwards, foaming started and con tinued for approximately 240 seconds. At that time the foam set and there resulted a flexible tufted mat comprising polyamide filament tufts. This tufted mat can be employed as artificial snow for skiing.

FIGS. 13-17 show how foam segments with synthetic tufts illustrated in FIG. 5 may be assembled into a finished brush. More particularly, as shown in FIGS. 13 and 14, filament tufts 300 of this invention protrude from a common foam segment 301. The common segment 301, can contain holes or other means for attaching it to another similar segment, but in the instant invention reference is made to the use of an adhesive. An end view of this segment is shown in FIG. 14. In FIG. 15 four

similar segments

301, 301, 301" and 301" are placed so that they are aligned with each other. As shown in FIG. 16, there is provided a molded cap 302. When cap 302 is placed over

segments

301, 301, 301" and 301" as shown in FIG. 17, with adhesive, a finished brush emerges as shown in FIG. 17.

By employing synthetic filament tufts attached through their base 401 with connector 402 as shown in FIGS. 18 and 19, a rigid or semirigid foam supported shoebrush may be constructed. The shoebrush shown in FIGS. 20 and 21 clearly demonstrates the simplicity in forming brushes. Employing tuft picking machinery as disclosed in U.S. Pat. No. 3,47 I ,202 it is possible to form continuous modular strips of thermoplastic pretrimmed brush constructions as shown in FIG. 19. By simply cutting the construction every 12 tufts, 48- tufted shoebrushes can be formed. The interconnected tufts can be supported in either rigid or semirigid foam substrates, depending upon the physical shape and flexibility desired.

As shown in FIG. 22, a belt of tufts 501 may be made from the flexible strip construction shown in FIG. 7. By placing a continuously connected flexible foam-supported belt of tufts 501 onto a shaft 502 and rotated in direction D, a tufted brushing tool 500 is formed.

The filament tufts of this invention may best be tufted by use of heat-sealing technique and preferably by bringing the heated nonworking ends of the synthetic filament tuft into contact with a suitable source of heated air and subsequently pressing the heated mass into a connector means. An inert atmosphere such as nitrogen, carbon dioxide, or vacuum can be employed when discoloration and degradation through oxidation of the thermoplastic filament is critical.

There is no restriction on the trim length, tuft diameter and tuft arrangement when manufacturing such foam-supported brush-type constructions.

The foregoing considerations conclusively demonstrate the advantages to be gained by providing self-supporting tufted arrangements of the type hereinbefore described. When such constructions are incorporated into brushes, mats and the like, there is attained new and novel constructions heretofore not known.

The invention in its broader aspects is not limited to the specific steps, methods, compositions, combinations and improvements described but departures may be made therefrom in the scope of the accompanying claims without departing from the principles of the invention and without sacrificing its chief advantages.

I claim:

1. The method of making tufted constructions comprising:

assembling a plurality of cut-to-length synthetic filaments to form at least one tuft;

heating the nonworking end of said tuft until said filaments fuse and said tuft extends from a fused mass of filamentary material;

mounting the fused end of said tuft on a flexible filamentary connector before said end cools so that said connector extends laterally through at least a portion of the fused end, thereby retaining said tuft on said connector when said end cools;

coating said connector and fused tuft end with a foam premix composition;

allowing said composition to foam and cure to form a tuft support, so that said composition forms a supporting cellular substrate with said connector and fused tuft end embedded therein and said working end of said tuft extending therefrom.

2. The method of claim 1 further comprising the steps of supporting a plurality of cut-to-length synthetic filaments to form a plurality of tufts; heating the nonworking end of each of said tufts until said filaments fuse; mounting the fused end of said tufts on said connector in a mutually spaced relationship before said ends cool to form an array of interconnected tufts extending from a fused mass of filamentary material, interconnected by said connector; coating said connector and tuft ends with said foam premix composition.

3. The method of claim 2 wherein the nonworking ends of said tufts are simultaneously heated and fused; and sub sequently, said tufts are simultaneously mounted on said connector.

4. The method of claim 2 further comprising orienting the connector in a preselected configuration before coating said connector and said fused tuft ends with said foam premix composition to form a tufted construction having said configuration when said coating foams and cures.

5. The method of claim 4 wherein said configuration is circular.

6. The method of claim 4 wherein said connector is oriented by wrapping said connector around a mandrel element.

7. The method of claim 6 wherein said foam premix composition is simultaneously applied to said connector and fused tuft ends mounted thereon as said connector is wrapped around said mandrel element.

8. The method of claim 7 further comprising continuously wrapping said connector, having said tufts mounted thereon, around a rotating mandrel in abutting rows and simultaneously applying said foam premix composition; and continuously removing said tufted construction from said mandrel as said composition foams and cures.

9. The method of claim 2 wherein said connector is a network of filaments and said tufts are mounted thereon in a preselected, mutually spaced array to form a tufted mat,- after said connector and fused tuft ends are coated with said foam premix composition.

10. The method of claim 9 wherein said connector is woven and said foam premix composition is flexible when cured.

11. The method of claim 2 wherein said foam premix composition is rigid when cured.

12. The method of claim 2 wherein said foam premix composition is flexible when cured.

Claims

1. The method of making tufted constructions comprising: assembling a plurality of cut-to-length synthetic filaments to form at least one tuft; heating the nonworking end of said tuft until said filaments fuse and said tuft extends from a fused mass of filamentary material; mounting the fused end of said tuft on a flexible filamentary connector before said end cools so that said connector extends laterally through at least a portion of the fused end, thereby retaining said tuft on said connector when said end cools; coating said connector and fused tuft end with a foam premix composition; allowing said composition to foam and cure to form a tuft support, so that said composition forms a supporting cellular substrate with said connector and fused tuft end embedded therein and said working end of said tuft extending therefrom.

3. The method of claim 2 wherein the nonworking ends of said tufts are simultaneously heated and fused; and subsequently, said tufts are simultaneously mounted on said connector.

5. The method of claim 4 wherein said configuration is circular.

9. The method of claim 2 wherein said connector is a network of filaments and said tufts are mounted thereon in a preselected, mutually spaced array to form a tufted mat, after said connector and fused tuft ends are coated with said foam premix composition.