CA2186393A1 - Resilient inlaid products and methods for making such products - Google Patents

Abstract

Disclosed are products and processes which utilize a reactive matrix (70) containing decorative elements to form the wear layer of a resilient, inlaid flooring product. The inlaid layer of the preferred floor covering products comprises an intelpenetrat-ing polymer network and a plurality of decorative elements at least partially embedded in the interpen-etrating polymer network. The method aspects of the invention include consolidating the matrix (70) by exposure to elevated pressure and initiating poly-merization of the reactive components in the matrix during the consolidation step.

Description

~WO9S/2700~ 21 B 63~ p~"~,~ c0ll49 T TCRTT.TT"A~T INL~ID ~KUI;JU-: ~ D AND
ME~rHOD8 FOR NAl~ING RUCF~ ~KUUUU~c~
Related APPliCationEI
This application is a continuation-in-part of application 5 Serial No. 08/66,~68, filed May 25, 1993, now pending.

Fiel~ of the Invention The present invention relates to inlaid surface covering products and to methods o~ manufacturing such products. r5ore particularly, the present invention relates to improved inlaid lO sheet materials useful as resilient surface coverings, inrlll~;n~ floor, wall and ceiling coverings; table, desk and countertop surfaces; automotive interiors; and the like.

Backqround of the Invention Resilient inlaid sheet materials have wide applicability 1'. as surface coverings and are commonly used as the wear surface, or as a portion of the wear surface, in floor, wall and ceiling coverings. As used herein, the term "inlaid" refers to ~ 8~3`93 W095l27007 2 1~ C~149 decorative sheet products characterized by a wearlayer having certain decorative elements which remain visually unchanged as the covering wears.
Traditionally, resilient inlaid surface coverings include 5 a wear surface comprising "~lrticles of resinous material, such as resinous chips, f lakes, granules, beads or the like.
According to one known method of f orming such products, a decorative inlaid pattern or design is built-up by applying particulate materials of different colors and/or shapes to a 10 substrate or backing portion of the surface covering. Groups of s~nri 1~ are commonly employed to arrange the particles in the desired pattern or design, and accordingly such ~_u~ Lu~:Lions are sometimes referred to herein as "stencil build-up" type of inlaid products. In such products, the 15 resinous particles are then consolidated under heat and ~L~5~.uL~: to form a wearlayer in which the decoration is carried substantially through the entire thickness of the layer.
According to certain more recent construction terhniq~
the inlaid characteristic is achieved by forming a matrix 20 comprising adhesive and resinous particulate material on the sur~ace of a substrate. In such constructions, the matrix material is ~r ucec~ed under appropriate ~L~S~UL~ and temperature conditions to form a layer in which the decorative aspect provided by the resinous particulate is carried through 25 the entire layer. These types of inlaid constructions, which are sometimes referred to herein as "matrix" constructions, are ? 1 ~3~
~ WO 9sl27007 3 ~ 0~149 - described, for example, in U.S. Patent No. 4,212,691 - Potosky et al.
While many variations of resilient inlaid surface coverings are known, among the most common type are matrix 5 inlaide comprising thermoplastic particulate material bound together by a thermoplastic adhesive composition. It has heretofore been common practice to utilize a poly (vinyl chloride) ("PVC") plastisol composition as the thermoplastic adhesive composition in such inlaid floor coverings.
It is understood by those skilled in the art that inlaid types of floor covering products are different in many i~portant ~,,ye~;L~ from non-inlaid products. For example, the presence of decorative particulate material in the wearlayer of inlaid f looring products is capable of producing aesthetic 15 ef~ects which are difficult, if not impos6ible, to produce in other types of flooring products. It is generally r~ro~n; 7~d thllt inlaid ~du~, can be manufactured to possess highly desirable three-dimensional effects and various textured appearances. Fur~hl- e, inlaid floor coverings are 20 frequently perceived by rrn! 5 and other users as having exceptional durability and high quality relative to non-inlaid materials. As a result of these and other properties, resilient inlaid floor covering products have generally enjoyed a signif icant degree of success in the f loor covering industry .
25 Notwithstanding the sllcr~cce~ of prior forms of resilient inlaid flooring, applicants have recognized that certain needs have remain unfulfilled ~y prior inlaid products. For example,

2~ ~393 W0 95/27007 4 P~ I49 the desirable appearance of most inlaid products i5 due in large part to the character of the decorative particles used, which particles are typically selected only after intensive study and analysis to suit the particular design objectives of 5 the flooring manufacturer. However, the manufac~aring techniques heretofore commonly used have sometimes resulted in, or at least tended to produce, a 6ubstantial degradation of the aesthetic properties being sought. More particularly, typical methods f or the preparation of matrix type inlaid surf ace 10 coverings involve introducing the decorative chips or flakes into a coating of thermoplastic plastisol adhesive on a substrate or backing surface, such as felt. The particle-laden thermoplastic plastisol is then consolidated and fused by the application of heat and/or ~esDu~ ~ from heated drums and/or lS plAni~hin~ rolls. See, for example, U.S. Patent No. 4,212,691 - Potosky et al.
Applicants have rDco~ni7Pd, however, that undesirable "streaking" of the decorative particles can sometimes occur as a result of the consolidation and/or fusion process. The term 20 "streaking", as used herein, refers to the phr- wherein decorative particles, and decorative resinous particles in particular, tend to deform or elongate in the direction that the decorative sheet travels as it passes around the drum and/or through the plAni~hing rolls. The desired aesthetic 25 and/or textured appearance of the inlaid surface covering is theref ore e ~ ther i~paired or not obtained .

~539 ~ woss/27oo7 5 ~ rc~ 49 - Applicants have also recognized ~he need to improve the "hand" or feel of certain prior inlaid floor covering products.
As used herein, the term "hand" refers to the proper balance between the elongation and tensile strength of inlaid sheet 5 materials. Prior inlaid prccucts produced by the stencil build-up method are frequently deficient in that they are undesirably stiff, that is, the elongation value is too low.
This condition detrimentally increases the dif f iculty of installing such products, ~CpP~iAl ly when such products are 10 produced in wide-widths, for example 6' or greater. This characteristic makes the products concomitantly less desirable and less commercially 6~lccPccful.
On the other hand, inlaid products produced according to the adhesive matrix technique are frequently considered to be 15 too limp, that is, the elongation value is too high. This condition is undesirable because "limp" floor covering products are r, ~uut..Lly perceived by c~n , as being of inferior quality .
Furth, ~, applicants have rP~ O~n; zed that certain 20 . ~;ial products made in accordance with the adhesive matrix technique have inferior indentation resistance, F~cpOCi~lly as compared to inlaid products made in accordance with the stencil build-up technique. As used herein, the term "indent resistance" refers to the ability of the surface coverings to 25 resist ind~ntation from repeated and/or prolonged application of pressure. Resistance to indentation is particularly L"-IL when the inlaid surface covering is used, for 21 863q3 Wo 95/27007 6 P~""~ ~ ll49 example, as a floor covering in a high traffic area that is subject to impact by heavy objects and/or exposure to concc.l~L~ted loads resulting from objects such as tables, chairs and the like.

~lumm~rY of the Invention ArplicAnts have dis~ uvc~ed i uved inlaid surface covering products and processes for producing such products.
The products and processes of the present invention uveL
numerous deficiencies recognized by applicants in prior products and ~luces~es~ including those defiri~nri~c identified hereinbefore. More particularly, applicants have discc~vered that products and proces6es which utilize a reactive matrix containing decorative elements to form the wearlayer are capable of providing resilient inlaid f loor covering products which have i uvcd hand, ~r:p~ciAl ly as compared to stencil ~uild-up products, and i uved indentation resistance, ~-cp~ri;~l ly as ~cd to inlaid products based on conventional adhesive matrix techniques. The preferred floor covering ~Ludu~;Ls of the present invention are resilient inlaid floor covering pLudu~;L; in which the inlaid layer thereof comprises an inteL~el-cl.Lc-ting polymer network and a plurality of decorative elements at least partially ~ in said interpenetrating polymer network.
The method aspects of the present invention pref erably include consolidating the matrix by e~O~ur e to elevated y aS~-u~ e and processing the particle-laden reactlve matrix to 63q3 ~ Wo95l27007 7 r~ e ~0~l49 - form an inlaid wearlayer by at least initiating polymerization of the reactive components during consolidation of the matrix.
Applicants have found that such processing steps have a strong tendency to eliminate the streaking problem associated with 5 prior methods.
The products and processes of the present invention also posses other advantageous features, as will become apparent from the detailed description hereinbelow.
Brief DescriDtion of the DrAwinq~
Each of Fig6. lA, lB, lC, lD and ~E is a diagrammatic, schematic drawing of one pmhotg;r L of the present invention, illustrating a preferred and typical process and apparatus theref or .

D¢t~il¢d De~c~iDtion of Prefe~.red F~h~-~ir ' ~
15 I. T~ ~ICODIJ-:Li~
The pref erred surf ace covering products of the present invention comprise an inlaid wearlayer of matrix con~l u-_~ion.
Importantly, the wearlayer of such preferred products comprises a plurality of decorative Pl~ ~3 at least partially Pmherl~lPd 20 in a composition comprising an interpenetrating polymer network .
A. Decorative Elements As used herein, the term decorative element refers to an element of the wearlayer which carries or exhibits discrete 25 decorative effects. In general, it is preferred that the W095/27007 ~ 393 p~"~ 01149 decorative element comprise decorative particles, and even more preferably decorative resinous particles.
The decorative particles may comprise chips, f lakes or granules prepared from resinou6 polymer compositions comprising 5 synthetic resins, plasticizer3, fillers, light and heat stabilizers, dyes, colorants and pigments, and any other conventional desired or required constituents. One decorative resinous particle which may be preferred in ceratin ~ -'i Ls are dry blended PVC resin particles of the type well known in lO the art.
According to P~horl i r ~S in which the decorative elements comprise resinous f lakes, the various constituents of the 6~1e--tecl flake formulation are formed into sheets of the desired th;ol~n~c~c by any suitable means, such as by passage 15 through rAlPnrl~r rolls or by extrusion processes, and the resulting sheets 50 produced are converted into the desired LLic shapes, for example, squares, spheroids, triangles, circles, annuli, other polygons, and the like, or irregular sizes and shapes, or mixtures of any or all of such shapes. If 20 a multiplicity of colors and hues are desired, then a multiplicity of separate sheets are so prepared, each with its own individual colorant, dye, or pigment, and then these sheets are individually cut into the desired sizes and shapes and then int~rmi Y~ in the desired or required proportions in order to 25 obtain the multi-colored effects. Sheets of different th; (-l~n~cc~c may be used also . The particulars of the particles used in such ~mho~ Ls are fully disclosed in U. S. Patent No .

~ Woss/27007 9 r~ [~l49 - 4 , 212, 691 - Potosky et al ., which is incorporated herein by ref erence .
The thiC~nPcc of the various sheets of material from which the decorative chips or f lakes are made depends primarily upon the desirkd pattern or design and upon the thickness of the layer of reactive adhesive into which they are to be ultimately ~'^d. Under normal cil- ul -La~i~ces, sheet th;~nPssPC of f rom about 1 to about 3 times, and pref erably f rom about 2 to about 3 times the thickness of the wet, tacky, ungelled reactive plastisol material are used. Such a thickness range is normally from about 5 mils to about 60 mils, and preferably from about 45 mils to about 55 mils. Naturally, various th; ~ nPcgpc of these g~ ic decorative chips or f lakes may be inf Prm; s~pc~, The th; ~l~nPcc of the layer of decorative chips or f lakes, as initially applied to the surface of the wet, tacky, lln^~ Pd plastisol varies widely but normally is in the range of from about 3 mils to about 30 mils, or even more, as desired or required by circumstances and conditions.
The decorative chips or flakes need not nP-Pcc~rily be all plastic. A particularly desirable effect is obtained by using small pieces, chips or flakes of a metal foil, such as ;mlm, which have been coated with a pigmented vinyl coating composition, similar to those described hereinbefore. These materials are sheeted, as described previously, and converted into y~ Lric shapes, as desired. The metal foil can be LL ~ 1 y thin and can range down as low as about 2 mils, or

3 93 WO gS127007 10 P~ 1149 even down to 0. 6 mil. The metal foil can even be embossed to give it an additional luster. The longe6t or the largest dimension of these decorative chips or f lakes may range ~p to as much as about 50 mils or lO0 mils, or even to 500 mils in 5 some circumstances.
B. The Inten~enetratinq PolYmer Network Interpenetrating polymer networks (IPNs) are a special class of polymer blends in which two or more polymers exist in a highly networked structure. As the term is used herein, 10 int~L~el.~LL~-ting polymer network refers to true IPNs, apparent IPNs, semi-IPNs, and combinations and hybrids of these.
A true IPN refers to those polymer networks in which the polymers in a system of two or more polymers are cross-linked to themselves but not to each other. In such a network, the 15 distinct polymer systems form networks that interpenetrate each other. A semi-IPN refers to those polymer networks in which one polymer system exists in an uncross-linked state while a second polymer system is cross-linked to itself. The term apparent IPN refers to co-continuous interpenetrating phases in 20 which none of the polymer5 is rhPm;rA11y cross-linked but which is nevertheless stabilized by physical polymer cross-links.
Although it is contemplated that the IPN of the present invention may be formed from polymeric materials of various types, it is generally preferred that the IPN comprise at least 25 a first thermopla6tic polymer int~L~..eLL~ted with at least one thermoset polymer. As is generally known, thermoplastic polymers are generally not cr--ss-linked polymers while ~ WO9512700~ 21 ~3~3 ~ 1149 - thermoset polymers are generally at least partially cross-linked. In such preferred embodiments, therefore, the IPN
comprises a semi-IPN and/or an apparent IPN.
Although it is contemplated that various techniques f or 5 f orming an IPN may be adaptabl~ ~or use in the present products, the preferred techniques are described in full detail hereinafter in connection with the method aspects of the present invention.
C. Thermo~lastic PolYmer A preferred thermoplastic polymer for use in the IPN
portion of the inlaid layer of the present product is vinyl resin, and even more preferably poly(vinyl chloride) resin.
Although the preferred thermoplastic polymer comprises PVC
homopolymer, many other vinyl resins may be used, for example, 15 vinyl chloride-vinyl acetate copolymers, vinyl chloride-vinylidene chloride copolymers, and copolymers of vinyl chloride with other vinyl esters, such as vinyl butyrate, vinyl propionate and alkyl substituted vinyl esters.
It is also preferred that the vinyl polymer comprise a 20 plasticized vinyl polymer of the type well-known in the flooring industry. Conventional plasticizers may be used for this purpose, although it is generally preferred that s~cnn~ ry plasticizers be avoided. Suitable plasticizers include dibutyl sebacate, dioctyl sebacate, butyl benzyl sebacate, dibenzyl 25 sebacate, dioctyl adipate, didecyl adipate, dibutyl phthalate, dicapryl phthalate, dioctyl phthalate, dibutoxyethyl phthalate, butyl benzyl phthalate, dibenzyl phthalate, di (2-3~3 Wo 95/27007 12 r~ 49 ethylhexyl)phthalate, alkyl aryl modified phthalate esters, alkyl aryl hydrocarbons, tricresyl phosphate, octyl diphenyl phosphate, dipropylene glycol dibenzoate, and dibasic acid glycol esters.
D. Thert~loset Polvmers It is contemplated that numerous ~hF' -~et polymers may be used to form the preferred IPN in accordance with the present invention. Nevertheless, applicants have found that acrylic polymers produce highly desirable results. Preferably, the acrylic polymers of the present invention are formed from compositions comprising, and even more preferably consisting essentially of reactive acrylate _I.ds~ and even more preferably reactive multifunctional acrylate _ _ 'q.
Exemplary and preferred reactive acrylates are reactive acrylate ~ and ol i ~ s. The terms "acrylate and "acrylate ol i J ~I as used herein refer broadly to substantially low molecular weight ~ -c characterized by the ~rese~lce of an acrylic acid or ester moiety (H2C=CHCOIR, wherein R is, for example, IIYdLOY~ or alkyl).
Particularly suitable acrylate ~ ~, are multifunctional acrylate - 2" that is, r ~, substituted with about two or more acrylic acid or ester groups . Such pref erred _ are ref erred to herein as acrylate - ~ having a functionality of about 2 or greater.
In accordance with certain preferred aspects of the present invention, the acrylate monomer comprises the reaction product of alcohol and acrylic ~cid reagent. The term "acrylic ~ Wo 95/27007 13 PC~r~Ss5/04149 - acid reagent" refers to acrylic acid and/or acrylic acid analogs which are reactive with alcohol. It is contemplated that the reaction of alcohol with acrylic acid reagent may comprise the reaction of one or more alcohols with one or more 5 acrylic acid reagents. The term "alcohol", as used ~2rein, refers to any organic ~_ _ ' which comprises one or more hydroxy substituents which are reactive with acrylic acid reagents. Accordingly, alcohols which may be reacted with acrylic acid reagents include mono-alcohols, diols, triols, and lO polyols, generally.
In accordance with certain pref erred r~mhorl i r -nts of the present invention, the monomer comprises the reaction product of diol and acrylic acid reagent. Preferred diols include ethylene glycol, propylene glycol, 1~ 6-h~yAnr~ ol and neopentyl 15 glycol. An example of a reaction product of diol and acrylic acid reagent which is particularly suitable for use in the plastisol composition 28 is l, 6-h~YAne~;nl rl;~ rrylate.
This material is commercially available from Sartomer Co. as SARTOMER 23 9B .
In accordance with certain other preferred aspects of the present invention, the monomer comprises the reaction product of triol and acrylic acid reagent. Preferably, the triol comprises trimethylol propane. An example of a reaction product of triol and acrylic acid reagent for use in the plastisol composition 28 is trimethylol propane trimethacrylate. This material is commercially available form Sartomer Co. as SARTOI~ER S-350.

2~ ~b3~3 W095/27007 14 1~ '0~149 Other suitable acrylate :, would be readily apparent to one of ordinary skill in the art in view of the present disclosure .
E. Product rol~erties Although applicants do not ~ end to be nec~cP::~rily bound by or limited to any particular theory of operation, it is believed that the formation of an interpenetrating polymer network containing substantially : ' ' '^~ decorative elements is in large part responsible for many of the beneficial properties and characteristics of the present invention. More particularly, the f ormation of an interpenetrating polymer network, particularly the preferred IPN's of the present invention, as an ~ lin~ material for the decorative elements contributes in large part to the avoidance clf the undesirable streaking rh^r - characterized by prior art proces6es. For example, applicants believe that ut i l; 7 i n j an IPN having a first polymer comprising thermoplastic resin and a second, th- - ~ polymer which int~L~ene ~L~tes with and into the thermopla8tic polymer is r-~p^n~ihle, in large part, for the ~^y-!Pl 1 r-nt hand exhibited by the present products . More specifically, applicants have discovered that combining polymer _ -- Ls in the manner and under the conditions described herein permits an inlaid product having a balance of tensile :~L~ yL~l and elongation that has heretofore been long sought but not achieved.
The products of the present invention preferably exhibit a rolling indentat~on resistanFe of no greater than about 5 mil, ~1 86393 ~ Wogs/27007 15 P~ ''Cll49 - more preferably no greater than about 4 mil, and even more preferably no greater than about 3 mil. Rolling indentation resistance is one property that is an important measure of the quality of wearlayers used in floor and wall coverings in that 5 it represent~ the ability of a wearlayer to resist pprr~npnt surface deformation resulting from movement of furniture, such as castered chairs and tables, along the surface. The results reported herein for rolling indentation resistance are ~etPr-ninPd by first est~hl ichin~ a path of travel, such as a 10 circular path. Seven points along this path are then identif ied and the initial th i rknpss of the sample i5 measured at each of these points. An apparatus containing three casters with a 100 pound load per caster is run along the predetPr-nin path such that each caster ~, ~v~ .es the entire path one time.
15 The th i rknPcs of the product at the seven predetermined points after the casters have traversed the path is then measured.
This same test is then repeated for a second sample of the same product. The rolling indent resistance is then reported as the average value in mils ( 0 . 001 inch) obtained by subtracting the 20 final thirknPcc at each prP~PtPrrinPA site and on each sample from the initial thirknPcc at each site on each sample.
The products of the present invention also preferably exhibit a stiletto indentation resistance of no greater than about 10 mils, more preferably no greater than about 9 mils, 25 and even more preferably no greater than about 8 mils.
Stiletto indentation resistance is a measure of the relative ability of a wearlayer to withstand pprr~npnt deformation W095/27007 ~6~8~393 resulting from exposure to stiletto heels. The values reported herein for Stiletto indentation resistance are de~Prm; nP-l by exposing a sample of the product to an applied load of 150 pounds on a one-half inch diameter ball for=a duration of about 5 ten seconds. The test is ~n~ tPd by providing a 2 ~ ._h x 6 inch sample of the f looring product and marking on the sample three test points . The gauge of the f looring sample is measured at each test point using a Randall Stickney gauge equipped with a one-quarter inch flat foot. A 150 pound load lO is applied to each test point for ten seconds via a one-half steel inch ball. The sample is allowed to recover from ~yO_ULe to the load for a period of one hour, after which the depth of the residual indent at each test point is measured using a one-quarter inch hemispherical tip gauge. The f inal 15 indentation thickness, measured in mils, is then subtracted from the initial thickness for each test point, and the average of these three readings is reported as the residual indentation resistance .
The preferred products of the present invention also 20 possess an exceptional balance between tensile _L~c.,yL~l and elongation . More specif ically, the present products pref erably exhibit a relatively high tensile strength, which is indicative of the durability and quality aspects of the product, while simultaneously exhibiting relatively high elongation values, 25 which are desirable from an installation point of view.
According to .~cper i~ l l y pref erred embodiments, the present surface covering products exh~bit a tensile strength of at 21 i~3~
~ WO9~l27007 17 r~ 0ll49 - least about 30 pounds, more preferably at least about 45 pounds, and even more preferably at least about 50 pounds. It is also preferred that the flooring products of the present invention possess an elongation of greater than about 25% and 5 less that about 60%, and more prefE~ ably of from about 30% to about 60%, with a range of from about 45% to about 55% being even more pref erred .
Tensile strength and elongation values reported herein are measured utilizing a Dilman tester, Model No. Motorized Ml. A
lO test sample of the flooring material measuring 1 inch x 1/32 inch x 5 inch, with the long dimension of the sample being parallel to the machine direction of the sample, is provided.
The flooring sample is then ~ Am;nAted such that the overlying wear layer is separated from the substrate. The wear layer is 15 then tested byplacing it in the tester with a one inch gap between the upper and lower jaws after calibration according to standard procedures. The apparatus is operated at a pull speed of about 12 inches per minute and otherwise according to standard ~LoceduL~s. The force, in pounds, at break is 20 reported as the tensile ~LL~ h. Elongation is similarly ~ tP~minPcl using standard pr~ luL s for such a Dilman tester, which provides an elongation value reported in inches. The value in inches is then multiplied by 100 and reported as elongation percent.
The products of the present invention also preferably exhibit a Taber stiffness value of no greater than about 600, more pref rably no greater than about 500, and even more `9~
WO gs/27007 18 r~ /01149 preferably no greater than about 450. The Taber stiffness values reported herein are det~ n;ne~l using a Taber st;ffnPcfi tester, Model 150-B or 150-D. The test utilizes a 2-3/4 inch x 1-1/2 inch test sample with the longer dimension parallel to 5 the machine di~ction. Because temperature and humidity influence stiffness, samples are flattened for 24 hours with a six-pound weight in a constant condition room (73F +/- 2F, 50% RH +/- 4% RH). The weight is removed from the sample one hour prior to testing. The testing equipment is operated 10 according to standard conditions with the degree switch set to 15. The average of the "right" and the "left" readings is det~rm;n~cl. This result is multiplied, flP~n~inq upon the pendulum weight, according to the following table to determine the resulting Tabor stiffness in half-Tabor stiffness units (TU/2).
penfl-ll Weiqht ~ulti~lY Averaqe Re~dinq BY:
None o . S
125 0. 62 250 1. 25 500 2.5 1, 000 5 0 2,000 10.0 II. ~HE PROCESSES
A. Providinq the reactive matrix In general, the present invention requires providing on a substrate a layer of reactive adhesive haYing decorative Wo s5/27007 2 ¦~ 6 3 ~ 3 r~ 149 elements on or in the reactive adhesive layer. For the purposes of convenience, this layer is sometimes ref erred to herein as a particle-laden reactive matrix or reactive adhesive matrix. As the term is used herein, "reactive adhesive" refers to adhesive or binding compositions which include reacti-~ e -Ls capable of reacting to form a polymer, copolymer, and/or polymer network. According to highly preferred ;--ntS, the reactive adhesive comprises, and preferably consists esscntially of, reactive plastisol, and even more preferably reactive PVC plastisol. As the term is used herein, "reactive plastisol" refers to a plastisol composition which includes reactive ic or oligomeric materials as ~:rr;he~l hereinbefore-In general, it is preferred that the decorative elements are substantially PmhP~lalPd in the reactive adhesive material, it being recognized that in some Pmho,a~ i r Ls at least some portion of the decorative element may not be in contact with the reactive adhesive. In certain preferred ~ - ts, for example, a portion of at least some of the decorative elements are exposed through the top of the wear layer and are therefore not in contact with the reactive adhesive . Nevertheless, f or the purposes of the present invention, such decorative Pl L~
are cnn~idPred to be substantially Pmh~PnoPd in the matrix layer .
It is contemplated that numerous techniques are readily available within the scope of the present invention for providing a particle-laden reactive adhesive matrix layer on a WO95/27007 ~ ~ 8~3~9~ ..,.. Cc~l49 substrate. For example, it is within the scope of the present invention that decorative elements may be simply admixed in a suitable blender or other mixing device with the reactive adhesive composition to produce a substantially homogeneous 5 distribution o~ decorative elements 11l the reactive adhesive.
This reactive adhesive with the decorative elements distributed therein may be coated or otherwise applied to a suitable substrate using conventional coating equipment. Eiowever, the use of a reverse roll coater to apply a particle-laden 10 plastisol composition is preferred in such P~o~li Ls. U.S.
Patent No. 5,178,912 - Piacente, which is assigned to the ARai~nDP of the present invention and incorporated herein by reference, A; aClosDc such techniques.
It is also within the scope of the present invention to 15 provide such a particle-laden reactive layer by f irst coating the substrate with a layer of reactive adhesive and then depositing the decorative elements onto the surface of such reactive adhesive. Either as a result of decorative elements sinking into the reactive adhesive and/or as a result of a 20 subsequent processing step, the decorative elements become substantially: ' ''?d in the layer of reactive adhesive. Such a process is described in more detail in connection with the attached Figures hereinafter.
The reactive adhesive of the present invention preferably 25 comprises the following: thermoplastic polymer; plasticizer for the thermoplastic polymer; and a reactive ,_ -nPnt. The thermoplastic polymer and plasticizer are preferably selected 3~3 W0 9sl27007 2 1 P~ ~ 149 in accordance with the rP~rh;n~s contained hereinbefore. In addition, the reactive components of tlle present invention preferably include not only the reactive monomeric and oligomeric ~ '~ identified above, but also catalyst for 5 the reactive ~ u--ds. In PsrP~ ly preferred Pl-ho~ s, the thermoplastic polymer and the plasticizer together comprise a fluid, coatable poly(vinyl chloride) plastisol composition and the reactive Ant comprises reactive th' - etting monomer and catalyst f or the monomer .
It is contemplated that a wide variety of catalysts would be suitable f or use in the pref erred reactive plastisol .
Preferably, the catalyst comprises a thermal catalyst which catalyzes polymerization and/or crosG-linking of the reactive monomer upon ~X~O:iulc: to elevated temperature conditions.
Applicants have discovered that certain catalysts are generally not preferred for use in accordance with the present invention while others are highly pref erred . While not intending to bound by or limited to any particular theory of operation, it is believed that this dichotomy occurs because 20 certain catalysts are deactivated by PVC resin. According to preferred Pmho~ nts discovered by applicants, therefore, the catalyst preferably comprises compounds characterized by the presence of a peroxide (-0-0-) moiety. It is contemplated that various types of peroxide catalysts may be used in the reactive 25 plastisol compositions of the present invention, ;nr~ ;nrJ
alkyl peroxide, for example, di-t-butyl peroxide and dicumyl peroxide, and peroxy ester c~ _ ~c. As the term is used 2 i ~393 WO95/27007 22 ~ /0'149 herein, a peroxy ester c, _-ld is a compound characterized by the presence of a -C(=O)-o-o- moiety, for example, t-butyl peroxybenzoate and t-butyl peroxy-2-methylbenzoate. The inventors have found that peroxy ester catalysts are preferred cataly6ts for use in the methods of the present invention t-Butylperoxy benzoate is particularly preferred and is commercially available a5 ESPEROX 10.
The catalyst is preferably incuL~oLated in the reactive adhesive composition in an amount sufficient to initiate polymerization and/or crosslinking upon ~x~o~u- a of the plastisol to elevated t ~ILu~as and pressures, as explained more fully hereinafter.
Applicant's have found that the proportion the PVC resin to reactive components is of special importance in r-mho~l i r Ls of the present invention which utilize reactive PVC plastisol as the reactive adhesive. More particularly, applicants have found that if the proportion of PVC resin to reactive acrylate i8 not within certain limits, then the unusual but highly desirable combination of physical properties according to the present invention will not be obtained. More particularly, applicants have found that the reactive plastisols of the present invention preferably have a PVC:reactive acrylate weight ratio of from about 2:1 to about 5:1, and even more preferably from about 3.5:1 to about 4.5:1.
The reactive PVC plastisol adhesive composition of the present invention preferably comprises from about 35 to about 50 parts by weight (pbw) of PVC resin, with from about 35 to 2~ 86393 WO 95127007 2 3 r ~ .'0 ~1~9 about 45 p~W being even more preferred. The reactive plastisol also preferably comprises from about 8 to about 12 pbw of plasticizer, with from about 9 to about 11 pbw being even more preferred. The reactive plastisol also preferably comprises 5 from about 8 to about 12 pbw of react- ~e acrylate, with from about 9 to about 11 pbw of reactiYe acrylate being even more preferred. Furthl e, from about 0.2 to about 0.5 pbw of catalyst is preferably incorporated in the reactive plastisol composition, with about 0. 3 pbw being even more preferred.
For: ' ';~ ~s in which the reactive components of the reactive plastisol comprise multifunctional acrylate monomer and peroxy catalyst for the monomer, the reactive plastisol composition preferably comprises from about 35 to about 45 pbw of PVC resin, from about 8 to about 10 pbw of plasticizer for 15 the PVC resin, from about 8 pbw to about 12 pbw of reactive monomer, and from about 0 . 2 to about 0 . 3 pbw of peroxy catalyst .
B. Consolidatinq the matri ,~
For Pmho~l i r--lts in which the decorative elements are 20 deposited onto a coating of reactive adhesive, the present methods preferably comprise consolidating the reactive matrix.
Although the decorative elements of the matrix may already be at least partially ~mh~ rl in the reactive adhesive upon the formation thereof, as described above, it is preferred to - 25 consolidate and thereby compact and densify the matrix, preferably by exposing the matrix to ~ ~s~u~ ~. Such a process serves to en~ure maximum ~m~ of the particles and, 2 ~ 86393 Wo 95l27007 24 F~I/~J..''C ~149 importantly, to eliminate or at least substantially reduce unwanted voids in the adhesive matrix layer.
)r~lin~ly, the consolidation ~Lvc~ule of the present invention preferably comprises exposing the reactive matrix to 5 time, temperature ~lld pressure conditions that are sufficient to cause substantial ~ - -nt of the particle in the adhesive matrix and to cause densification of matrix layer. Preferred conditions comprise F-Ypoci ng the reactive matrix layer to pressures of from about 150 to about 350 pounds (gauge) per 10 square inch (psi). Such exposure may be provided by any one of several known means, including pressure drums and pl ~n i ch~r rolls .
In certain preferred embodiments of the present invention, consolidation is carried out in two or more stages. Such a 15 staged consolidation process is especially preferred for ~ o~lir Ls in which the decorative eléments are deposited on a coating of reactive adhesive. More particularly, it is preferred in such 'i- ~s that the reactive adhesive matrix is exposed to elevated pressures in a first consolidation step 20 preferably by passing the substrate containing the particle-laden adhesive matrix through a heated ~- e6Lu~ ~: drum which preferably exposes the matrix to pressures of from about 150 to about 300 psi. Such an operation serves not only to initiate consolidation of the matrix, but also to ensure sufficient 25: `-- -nt of the decorative elements into the adhesive. The adhesive matrix is then preferably exposed to higher ~)LeS~ULeS
in subsequent stages of consolidation.

WO 95/270~7 25 r~u~
- Subsequent stages of consolidation preferably comprise introducing the matrix into one or more pl~n;chpr rolls, and preferably cooled pl~n;~h~ rolls. The product is preferably exposed to ~Les~ ULdS of from about 330 psi to about 350 psi in 5 such pl~n;f:h~r rolls.
C. Gellin~ and fusion of the matrix In the preferred multi-stage consolidation: ' -;r Ls, the f irst stage of consolidation and gelation are carried out together in a heated ~L ~52.UL~ drum, as explained more fully 10 hereinafter.
It is known that fluid PVC plastisol compositions comprise liquid plasticizer and a dispersion or suspension of PVC re6in in the plasticizer. As is well known to those skilled in the art, the traditional, non-reactive fluid plastisol compositions 15 previously used must be processed to develop the desirable wear resistant properties required for resilient flooring. The application of heat to non-reactive f luid plastisols generally causes physical changes in the rheology of the plastisol. That is, the fluid plastisol composition passes through or enters a 20 gel phase as the t~ LuLe: of the plastisol is raised to a sufficiently high level.
For the yuL~oses of convenience, the term "gelation temperature range" is used herein to refer to the range of t~ ~ILuLes ~rAnn;nq from about the pre-gelation stage of a 25 plastisol, or about the initial increase in plastisol viscosity, to about the gel point. Techniques are well known and available to those skilled in the art for detc~rrn;n;n~ the 21 8~393 W0 95l27007 2 6 ~ 9 gel point of any particular plastisol. Por example, the gel point may be measured using a gelation plate which is heated only at one end, thereby developing a temperature gradient from one end of the plate to the other . When a f luid plastisol 5 composition is cast onto the plate, the t~mperature of the plate at the point the plastisol loses its fluidity is frequently referred to a5 the plastisol's gelation temperature or gel point.
The gelation temperature ranqe of any particular plastisol 10 is a function of many variables, including the type and relative amounts of plasticizer re5in present. It is generally contemplated, however, that the gelation temperature range of the fluid plastisols of the present invention will take place at t~ ~eL c. LUL ~5 of f rom about 15 0 F to about 3 4 0 F, and 15 pref erably f rom about 2 8 0 F to about 3 4 0 F . Af ter 1 ~ P
gelation, the plastisol is generally a :,ub~,~ant.ially dry, relatively firm solid.
It is generally preferred that the adhesive matrix of the present invention be gelled and fused. As is well known to 20 those skilled in the art, the gel comprising the plasticizer and the PVC resin will fuse upon the application of s~ffic iPr,t heat thereto. In particular, it is known that the heating of a plastisol suf f iciently past its gel point causes the plasticizer molecule5 to begin to become in- UL~OL~Ited into the 25 molecules of the PVC polymer, and "fusion" begins. As heating continues, the plasticizer becomes substantially integrated into the PVC polymer. In such a state, the pla5ti~01 is said 21 8~3`93 W095/27007 27 rC~ 9 to be a "fused-plastisol. " The term "fusion temperature range"
is used to refer to that temperature range over which fusion takes place, typically a range of t~ aLuLes bP~J;nnir~3 above - about the gel point. In many preferred r~mho~i ntS, the fusion 5 temperature range is ~reater than about 280F.
In certain -'i Ls of the present invention, tlie reactive particle-laden matrix may be both gelled and tused by simply elevating the temperature of the layer for a time sufficient to effect gelation and fusion. In such ' ';- -ntS~
lO fusion may be obtained by heating the consolidated product to a temperature of from about 325F to about 470F for a period of time of from about one minute to about six minutes.
Pre~erably, the product is heated to a t aLuL~ of at least about 385F, dPrPn~lin~J upon the nature of the particular 15 polymeric materials which are being used. This may be accomplished, for example, by passing the layer through a fusion oven.
It will be appreciated that the consolidation, gelation, and fusion steps described herein need not nPcP~c~ily occur 20 instan~nPo~lCly and separately. Rather, it is preferred in ceratin Pmho~ Ls that the steps of consolidation, gelation and fusion occur in stages, and that two or more of these steps may overlap with one or more of the other various steps. For example, it is preferred that both consolidation and gelation 25 of the matrix are at leact initiated by substantially simultaneously exposing the matrix to conditions of elevated pressure and t~ LUL~:. This can be done using, for example, ` - 2 1 WOgs/27007 86393 P~11-J~. 0~149 a heated pressure drum. For ~mhQ~iir Ls in which the decorative elements are already distributed in the reactive adhesive at the time the adhesive is applied to the substrate, the application of pl~st,u-e by the heated pressure drum is 5 p~ imarily for the purpose of smoothing the layer . On the oth~r hand, for ~ r-s in which the decorative elements are deposited onto a coating of reactive adhesive, the ~L~~`ULeS
exerted by the heated ~ ULe drum are relatively high, preferably from about 150 psi to about 300 psi, and are applied 10 not only for smoothing, but also for the purpose of consolidation. In the latter case, gelation and cnn~:c~ tion are at least initiated substantially simultaneously.
Furth, t:, it is contemplated that in certain ~mhorlir l_s fu6ion of the plasticizer and PVC resin may also begin to occur 15 in the heated pressure drum. Thus, it is seen that the steps of consolidation, gelation and fusion may all take place to some degree in a single piece of equipment.
D. Polvmerization of the reactive matrix Importantly and critically, the present methods require 20 polymerizing the reactive Ls of the reactive matrix.
Furth. e, for ~mho~i- Ls in which the reactive matrix comprises substantially non-reactive polymer, such as PVC
resin, and reactive components, it is highly preferred that the methods comprise at least partially polymerizing the reactive 25 _ ~n~nts in the y-esence of the non-reactive polymer to form an IPN . It is believed that such pref erred ~L ocesses serve to "lock" the de~orative elements into the polymeric matrix and .

21 ~3~3 wossl27007 29 r~ . tl49 thereby contribute significantly to the advant2ges assolciated with the present invention.
According certain preferred embodiments, at least partial - polymerization of the reactive, _ ~c occurs prior to final 5 consolidation of the wearlayer. Such a p-ocess may be ;ChFrl, for example, by FYp~c;ng the layer to consolidation ~L ~SDUL a in two or more stages, with the earlier stage utilizing a lower ~Lt:5~ULe exposure than the later stage or stages. In this way, the inlaid layer is exposed to the 10 highest consolidation ~LC:SSULI:: only after the adv~ntagec-~lc properties of the present invention are at least partially imparted by at least partial polymerization of the reactive , _ c .
As is understood by those skilled in the art, prior 15 plastisol compositions containing decorative elements require exposing the matrix layer to consolidation under heat and ~1eSDUL ~. As mentioned hereinbefore, it was during this process that streaking and elongation of the decorative F.1~ L~ - O-~;ULL~d. Applicants have found, however, 20 that this undesirable rhF- - is substantially avoided by the preferred processes of the present invention which re~uire that the reactive components of the reactive adhesive undergo at least partial polymerization during the consolidation step.
Such preferred processes serve to at least initiate formation 25 of an IPN so that the pressures normally experienced by the adhesive matrix layer during consolidation do not elongate or deform the decorative elements.

-21 ~393 wosS/27oo7 30 r~ 0~149 --According to highly preferred F~mhc~l; l.Sr applicants have found that it is critically important that the reactive components of the reactive plastisol be selected to at least initiate polymerization prior to PYrosin~ the reactive matrix S to the maximum pressu~-~ experienced by the matrix during the consolidation step. For the preferred multi-stage consolidation step of the present invention, it is preferred that polymerization at least be initiated prior to the final stage of consolidation, and even more preferably that polymerization be initiated during the initial stage of consolidation .
Applicants have also found that it is preferred to at least initiate polymerization of the reactive ~~ L~ of the reactiYe matrix prior to full fusion of the PVC resin in the plastisol, and even more preferably prior to substantial initiation of fusion.
Initiation of polymerization in accordance with the present invention is desirably achieved by PYrOCin~ the particle-laden reactive matrix to processing in a heated pressure drum, as de5cribed in further detail hereinafter in connection with the Figures.
III . DT ~ lQN OF THE TT T TTSTRA~T n E~BODTMT~T~IT
A preferred pmho~l jr ~ of the present invention will now be described below in connection with the attached Figures.
With specific reference to Fig. lA of the drawings, there is shoyp therein ~ ~ot~t~bl~ ~upply rol~ lO ~ro~ whioh ls woss/27007 31 P~ 0ll49 delivered a relatively flat, fibrous or non-fibrous backing sheet material or substrate 12, such as a fibrous, felted or matted relatively flat sheet of overlapping, intersecting fibers, usually asbestos or of cellulosic origin. The 5 sut~strate 12 may, if desired, be a woven, non-woven, knitted or otherwise fabricated textile material, paper stock, a sheet or f ilm of a synthetic or man-made plastic or any of the materials clo5erl, for example, in U.S. Patent l!los. 3,152,002;
3,232,780; 3,239,364; 3,359,352; and 3,660,187.
A base resinous polymer composition 14, which is preferably a polyvinyl chloride (PVC) plastisol, is substantially uniformly applied to the surface of the substrate 12 at a coating station 16, for example, by means of a reverse roll coater.
The thickness of the base resinous polymer composition or plastisol 14, as it is applied to the surface of the substrate 12 and is still wet, is substantially uniform and is in the range of from about 0 . 005 inch to about 0 . 060 inch, or even thicker, if so desired or required by future requirements or 2 0 needs .
The particular means for applying the base resinous polymer composition 14 to the surface of the substrate 12 does not relate to the essence of the present invention and substantially any suitable coating means may be employed.
- 25 Although the preferred synthetic resin for the base resinous polymer composition 14 is a PVC homopolymer, many otheF vinyl resins as described herelnbefore may b~ used.

W0 95/Z7007 3 2 1 ~ 9 In addition to plastisols, organosols and aqueous lattices, for example, aquasols and hydrasols, may be used, employing as the dispersing or 5~cpr-n~1 i n~ media organic solvents and water, respectively.
S Other constituents of the base resinous polymer composition 14 may include blowing or foaming agents, such as azodicarbnn~mi-l~, if a blowing or foaming ~LUUedULI:: is desired;
various accelerators/stabilizers, initiators and catalysts, for example, zinc octoate and lead phosphite; various heat and/or light stabilizers, for example, metallic soaps; W ab5uL~_~D;
colorants, dyes and pigments, including titanium dioxide;
solvents and diluents, for example, methyl ethyl ketone, methyl isobutyl ketone and dodecyl benzene; fillers, for example, clay and limestone; viscosity modifiers; antioxidants; and bacteriostats and bacteriocides.
After the base resinous polymer composition 14 has been applied and adhered to the substrate 12, it is then heated in an oven or other suitable heating apparatus 18 maintained at an elevated t~ ~ clLULe of from about 240F to about 450F, and preferable from about 260F to about 410F for a period of time of from about one minute to about f ive minutes, whereby th~e composition gels and becomes firm. The t~ aLuLc: and the time are interd~r~n~nt and the higher the t~ CILUL~, th~!
shorter the time and vice versa. The elevated temperature, however, is not so high as to activate or to r~ se any blowing or foaming ~gent w~ich may be present in the ~ W095/27007 33 r~.,.,~ oll49 - formulation of the base resinous polymer composition 14 as to cause blowing or foaming at this time Optionally, the gelled or firmed base resinous polymer composition 14a may then be printed or coated, if so desir 3d, 5 at a printing station 2 ~ by means o~ two or more pairs of suitably engraved printing rolls 22 and 24 with printing ink compositions containing dyes, colorants, pigments, and the like, if a design or pattern is desired or reguired in the final product. The printing ink composition may also contain 10 synthetic resins, plasticizers, stabilizers, antir~Y~ ntc~ and blowing or foaming modifying agents in selected areas if an ' ~fil:ptl or textured surface appearance is desired or reguired.

Drying of the applied printing ink composition is accomp}ished by air drying, or by the use of conventional heating and drying 15 procedures.
In certain ~mho~l; Ls, the blowing or foaming action of the potentially foamable base resinous polymer composition 14 may be of such a strong or vigorous nature that the gases which are developed or released by the blowing or foaming agent tend 20 to escape upwardly from the heated base resinous polymer composition and tend to enter any wear layer or any other l~yer lying above it to undesirably affect the, Lhl,es~ and ev~ nes6 of the wear layer surface. This could be ruinous to the smoothness and evenness of surfaces, if such 25 characteristics are desired, and could be undesirable from an aesthetic viewpoint.

W09s/27007 Such undesirable effects may be avoided by placing a relatively thin barrier coat or layer having a th i rl~n~cs of only about 6 mils or less, down to about 1 or 2 mils, on top of the base resinous polymer composition 14, either before or 5 after any printed pattern or design is applied thereto but before any further coatings or layers are applied. Such a barrier coat or film effectively prevents the gases from ~-qclr;ng upwardly from the blowing or foaming base resinous polymer composition.
Such a barrier coat is applicable as a f ilm but is normally applied as a plasti601 or resinous polymer composition in a thin layer of a resin, such as a vinyl chloride polymer or copolymer having a relatively high molecular weight. Gelling of such a barrier coat naturally follows at an elevated 15 temperature below the activation or rle~ ~- ition t~ .Lu-,a of the blowing or foaming agent. A typical barrier coating station 25 is generally indicated in Fig. lA of the drawings.
Two typical barrier coat formulations are as follows.
~3~* Parts*
20 Polyvinyl chloride, high mol. wt., dispersion grade, inherent viscosity 1. 4 89 90 Polyvinyl chloride, high mol. wt., hlPn~in~ resin, inherent 25 viscosity 0. 9 11 10 Dioctyl phthalate 6 ~rnY; ~ soya oil 5 5 W095~27007 35 I~~ 49 2, 2, 4-trimethyl-1, 3-pentanediol diisobutyrate 6 . 9 8 . 8 Butyl benzyl phthalate 29 19 . 6 Polydodecyl benzene 8 . 5 5 . 5 5 Ba-Zn phosphite stabilizer ,- . 25 3 W absorber 0.32 0.32 Toner 0 . 01 0 . 01 ~Parts by weight, based on 100 parts of resin. phr As shown in Fig. lB of the drawings, the gelled resinous 10 polymer composition 14b is then advanced to a coating station 26 where a reactive plastisol 28, which is a wet, tacky, ungelled plastisol, is substantially uniformly applied to its surface, for example, by a suitable coating applicator roll 30 dipping into a conventional coating par 32.
The thickness of the layer of wet, tacky, ungelled plasti601 28 a6 it is applied to the sur~ace of the base resinous polymer composition 14b and is still wet is substantially uniform and is in the range of from about 20 mils to about 26 mils. The ~hic~npcs of the coating of the layer of 20 lln~el lecl plastisol 28 may be controlled by an air knife doctor device 34 and a backing roll 36. The particular means for applying and controlling the th; rkn~q~:: of the layer of n~ rl, reactive plastisol 28 does not relate to the essence of the present invention and substantially any suitable coating 25 device may be employed, provided it is capable of accurately applying and controlling the th i rl~n~c6 of the coating .

? ~ 8~393 W095/27007 36 ~ 5'0~149 The layer of reactive adhesive composition 28 which is, of course, ungelled, uncured and unfused, has a viscosity in the range of from about 2500 centipoises (cps) (Brookfield) up to as high as 3500 cps (Brookfield No. 3 spindle, 20 rpm, 87-89F) 5 provided the plastisol r~rlins its wet, tacky properties and characteristics .
As will be seen s~lhceqllPntly, the thi~-knP~s of the layer of wet, tacky, ungelled plastisol 28 and its viscosity are among the factors which will determine the metering and the 10 control of the amount and the l-h i t~knp~ of the layer of decorative chips or f lakes which are deposited and adhered thereon .
As shown in Fig. lC of the drawings, the gelled resinous polymer composition 14b and the layer of ungelled resinous 15 polymer composition 28 thereon are then f~,~w~-lded to a decorative chip or flake coating device 36. The resinous polymer composition 14b and the layer of ungelled resinous polymer composition 28 passes over a rotatable index roll 38 and then under a supply hopper 40 containing chips, flakes or 20 granules 42 which are to be substantially uniformly deposited on the surface of the layer of wet, tacky, ungelled plastisol 28 for subsequent adhering and: ` 'tl;n~ therein.
The preferred equipment for supplying the particles 42 to the reactive adhesive does not form a part of the present 25 invention and is fully disclosed in U.S. Patent No. 4,212,691.
As the layer of adhesive plastisol composition 28 passes f orwardly underneath the f lexible seal b ade memb-r 54, 2 ~ 8~3~3 o 9~/27007 37 F~l/.).,,~'C 1149 portion of the supply bank of decorative chips or flakes 42 is deposited substantially uniformly thereon and is adhered thereto . Pref erably, the decorative chips or f lakes are deposited onto the plastisol composition 28 in chip:adhesive weight ratio of from about 1.5:1 to about 2.0:1. More preferably, a weight ratio of about 1. 8 :1 is used.
Substantially simult~n~r~lcl y or immediately after deposition of the decorative chips .or f lakes, the substrate carrier 12 carrying the gelled resinous polymer composition 14b and the layer of wet, tacky, ungelled plastisol resinous polymer composition 28 thereon come into sliding contact with the angularly incl in~d bed plate 46 and is guided forwardly and upvardly in positive fashion thereby.
A rotating back beater 56 which is provided with radially-P~Pnrlin~ spokes or veins is supplied just beyond the upper end o~ the angularly ;nrl ined bed plate 46 and intermittently strikes the back surface of the carrier substrate 12 whereby it is shaken or vibrated so that any partially, insufficiently or loosely adhered decorative chips or flakes 42 which have not previously slid or fallen backwardly and downwardly into the supply bank are given an additional chance to be released to slide back into the supply bank, whereby only well-adhered decorative chips and flakes remain on the surface of the layer of wet, tacky, ungelled plastisol 28.
l~e substrate 12 carrying the gelled base resinous polymer composition 14b and the layer of wet, tacky, ungelled plastisol r-sinous polymer composition 28 thereon with the adhered ~ ~ 8~3~3 W095l27007 38 P~ 11149 decorative chip or f lake materials thereon then passes onward and upwardly over a rotatable guide roll 58 to be forwarded for further processing and finichin~, including conso1idation, gelation and fusion, as fliccllc5~q more fully hereinafter Such further processing and fin;ching opel3tions may take many dif f erent f orms and may involve many dif f erent f orms of apparatus One such further processing procedure is illustrated in Fig lD, wherein there is shown the f irst 6tage of a multi-stage consolidation p.uceduLæ employing a large steam-heated (or superheated steam-heated) rotatable cylindrical drum which is capable of being heated to elevated temperatures of about 400F, or even higher, to initiate consolidation In general, it is pref erred that ex~o- uL è of the adhesive matrix to such a heated drum raises the temperature thereof to about 300-310F This is also a gelation stage and the f irst stage of a multi-stage polymerization Located around the cylindrical surface of the heated drum are a plurality of heated, rotatable pLæs~uLe-applying cylindrical press rolls 62, 64, 66 and 68 which are capable of applying ~Læs~uLe to any materials placed on the cylindrical surface of the heated cylindrical drum 60 P~æs,~uLæs of up to about 300 psi of contact between the heated cylindrical drum 60 and the individual press rolls 62, 64, 66 and 68 may be used Applicants have found that it is highly preferred for the adhesive matrix layer on product 70 to be exposed to relatively low ~Les~uLes, and preferably pr--ssures of no gr~ater than 2~ 86393 ~ WO sS/27007 3 9 ~ 0 l l 19 - abQut 200 psi, upon initial contact with the heated drum 60.
A6 a result, polymerization of the reactive components of the matrix is initiated while the matrix is exposed to relatively low consolidation pressures. This may be achieved, for 5 example, by applying relat~vely low pressures, for example 150-200 psi, to press rolls 62 and 64 while applying higher ~JLeSDULeS, for example from about 250 to about 300 psi, to press rolls 66 and 68. In this way, the first consolidation stage is itself a multi-stage process insofar as different 10 stages of ~resDuLe are utilized. Because the preferred dwell time of the adhesive matrix around the heated drum 60 is about 20 to about 60 seconds, this permits a period of about 10 to about 30 seconds for initiation of polymerization under conditions of relatively low ~leDDuLe consoIidation.
Thus, the substrate 12 containing the base composition 14b and the plastisol composition 28 is exposed to temperature and sDuLe conditions from the heated drum 60 and the press rolls 62, 64, 66 and 68 for a time effective to substantially simultaneously (1) at least initiate polymerization of the 20 reactive - -~ts of the reactive plastisol and (2) at least initiate consolidation and gelation of the particle-laden plastisol layer. According to preferred ~ ~; Ls, the drum 60 heats the adhesive matrix to a temperature of from about 2950F to about 315F, with a temperature of from about 300F to 5 about 310F being even more preferred. In highly preferred ts, the cylindrical drum 60 produces a matrix t~ _ - o,Lur e of about 30sF. Applicants have found that suc~

W095/27007 40 P~ 01149 preferred procedures result in at least the initial conversion of the reactive plastisol into an IPN. That is, heating and/or pressurizing the particle-laden reactive layer as described herein produces polymerization, and preferably cross-linking, 5 of the leactive ~ _ ' in the presence of the PVC resin and the decorative elements, which in turn at least begins the formation of the preferred inteL~ LLGting polymer network.
It will be appreciated, however, that further reaction of the reactive ^-~ts may pref erably occur in subsequent 10 processing steps, such as fusion of the wearlayer. In these -~li Ls, the IPN becomes more highly networked and the full advantage of the present is realized.
Exposing the matrix to the elevated t~ , - G~UL~:S of drum 60 not only pref erably initiates polymerization of the reactive ts, but also causes at least partial gelation, and even more preferably substantially full gelation, of the plastisol.
During the preferred initiation of polymerization and gelation, the present processes also preferably comprise initiating consolidation of the adhesive matrix layer. This 20 initial consolidation stage is achieved primarily through the plurality of heated, rotatable press rolls 62, 64, 66 and 68.
During this initial consolidation stage, the decorative surface covering is preferably exposed to ~res,.uLe:s of from about 150 to about 300 psi, with the pressures increasing as 25 the product 70 travels around the periphery of the drum.
Preferably, the decorative surf~ce covering is exposed to a 1~ WO95/27007 41 I. I/IJ,, _. 1149 - ~r~ U- ~ of no greater than about 300 psi in the first st2ge of consolidation .
The time required for the ungelled, coated substrate to be partially cured and consolidated by passing between the drum 60 and the press rolls 62, 64, 66 and 68 may be sei ected as desired and is a function, among other parameters, of the nature and thickness of the resinous compositions and the t~ -- aLur 2s and pr~5~uLes used. Preferably, the ungelled substrate is exposed to the above noted pref erred elevated tL.~.~eL a LUL eS and presDuL es f or a period of time of from about 20 seconds to about 40 seconds, with a period of time of from about 25 seconds to 35 seconds being preferred. Preferably, the pre-gelled, coated substrate is 6ubjected to such elevated temperatures and ~leS`iULt:S for a period of time of about 30 seconds to cause partial polymerization, partial consolidation and substantially complete gelation.
As one of the results of this consolidation stage, a partially consolidated resinous polymer sheet materiâl 70 is obtained, wherein the decorative chips or flakes 42 are - 'c~d into wet, tacky, ungelled plastisol 28 and form a particle laden plastisol having a relatively firm, smooth surf ace tightly bonded to the base layer resinous polymer composition 14 situated on the underlying carrier substrate 12.
The gelled, partially consolidated, partially polymerized matrix 70 is then pref erably processed so as to complete consolidation, if that is required or desired, and to complete fusion. It is contemplated that complete fusion of the Woss/27oo~ 42 1~ '0~149 plastisol may occur as a result of simply exposing sheet 70 to elevated temperatures in a fusion oven of a type common in the rlooring industry (not shown). In such ~ho~ s, it is preferred that the reactive plastisol matrix is substantially 5 fully fused and the reactive ~ Ls thereof are substantially fully polymerized. Fusion in such cases is normally obtained by heating the product 70 to a t~ -- aLuLt: of from about 325F to about 470F for a period of time of from about one minute to about six minutes. Preferably, the product 0 70 i5 heated to a temperature of at least about 385F, ~"r"n~l i n :1 upon the nature of the particular polymeric materials which are being used. Such elevated temperatures are also normally sufficient to bring about blowing and foaming in the base resinous polymer composition, if a blowing or foaming 15 agent was originally included in the base formulation. Blowing or foaming may take place in any and all areas wherein the effect of the blowing or foaming agent has not been inhibited by the inclusion of an inhibitor in certain areas of the 8~'1 ect~d portions of the desired printed pattern or design 20 applied by the printing ink compositions.
In more preferred ~ ho~ ts~ however, consolidation, polymeri2 ation and fusion is completed in a stage-wise process as illustrated in Fig. lE. In accordance with such a process, the gelled, partially consolidated, partially polymerized 25 product 70 is introduced to an oven comprising a series of infrared heating banks, shown schematically in Fig. lE as 80.
This step thus preferably further elevates the temperature of 2~ 863~3 WOgS/27007 43 ~ 01149 the adhesive matrix layer to about 370F and causes further polymerization of the reactiYe ~ -~AntS. Preferably, fusion of the plastisol into the PVC resin i5 also at least initiated by introduction of the product 70 into the oven 80.
The rartially fused product 70 which exits oven 80 is then il.LLuluced to plAn;~h~r rolls 81 wherein the adhesive matrix layer of product 70 is exposed to a second stage of consolidation . It is pref erred that during the second stage of consolidation the adhesive matrix layer is exposed to pL~::S~uLt:S
of from about 320 to about 350 psi, and even more preferably of from about 330 to about 350 psi. It is also preferred that the rlAnichPr rolls 81 are cooled pl~n;chpr rolls.
The product which leaves pliln;ch~r rolls 81 is then i~.LLu-luced into a gas fired radiant oven 82 wherein the adhesive matrix is preferably substantially completely fused ~nd polymerized. Accordingly to preferred ~ - Ls, this rinal fusion and polymerization stage comprises heating the ~dhesive matrix to a t~ ALuLt range of from about 270 to ~bout 320F for time sufficient to effect substantially complete fusion and polymerization. Applicants have found that such times are pref erably f rom about 1 to about 4 minutes .
Optionally but preferably, the product 70 exiting oven 82 is exposed to yet a second set of plAn;ch~r rolls 83. While rlAn; ch~r rolls 83 serve, in part, to further consolidate the -25 adhesive matrix layer of product 70, it is preferred that such pl:~n;Ach~r rolls also comprise embossing rolls which emboss the surface of the product 70 in a desired pattern or design.

WO 95/27007 44 PCrrUSsS/04149 In pl;~ni chor rolls a3, the adhesive matrix layer is also preferably exposed to pressures of from about 320-350 psi, and even more preferably of from about 330-350 psi.
The f inal product is then advanced to a rotatable wind-up 5 roll 84 for disposition or for further processing 2~nd h~nrll ;ng, as desired or roqttlrecl The present invention will be further described with particular reference to the following examples which are primarily illustrative of the present invention.
E~SPLE I
The apparatus schematically and diagrammatically illustrated in Fig. 1 is used to carry out the following process:
The fibrous backing sheet material or substrate comprises 15 a relatively flat, 0.040 inch thick fibrous sheet of felted and matted asbestos fibers provided with an acrylic smooth leveling coatinq thereon.
The ba6e resinou6, potentially foamable polymer composition, such as PVC plastisol, is applied to the substrate 20 to a substantially uniform wet thickness. Gelling and firming of the potentially foamable base resinous polymer composition takes place in a heated oven at an elevated temperature of about 300F for a period of time of about three minutes. The gelled, firmed PVC plastisol is then printed with a pattern or 25 design, if desired, after which a barrier coat layer is applied to a thickness of ~bout 3 mils on the sur~ace of the PVC base layer .

~ Wo 95/27007 2 1 8 6 3 9 3 ~ o 1149 The printed, gelled and firmed base layer plastisol having a barrier coat layer thereon is then coated with a layer of a wet, tacky, ungelled PVC plastisol resinous polymer composition containing: about 33% by weight of calcium carbonate filler;
5 about 9% by weight butyl benzy~ phthalate plasticizer; about 40% by weight of PVC homopolymer resin; and about 10% by weight SARTOMER 350. The PVC homopolymer resin is a 1" ~ m molecular weight resin comprising a mixture of 8096 by weight of dispersion resin and 20% by weight of suspension resin. The 10 dispersion resin is sold by Occidental Chemical Co. under the trade designation 688C and the suspension resin is 601d by Borden under the trade designation R501. The reactive plastisol further contains 3% by weight, based on the weight of SARTOMER 350, of ESPEROX 10.
The gelled base resinous polymer composition with the layer of ungelled, wet, tacky plastisol thereon is then advanced to a chip or f lake coating station, whereat there is deposited substantially uniformly thereon a layer of resinous decorative chips or flakes in a chip:adhesive weight ratio of 20 about 1. 8 :1. The coated substrate is then forwarded to a con~:oli~Ation apparatus, such as shown in Fig. lD, for at least partial polymerization and/or consolidation.
The main, s~lr~rh~Ated steam-heatf d rotating drum has a t~ , a,~ULe: of about 410F and the four peripheral rotatable 25 LJLt~Ur ~ applying rolls 62, 64, 66 an~ 68 apply ~Les.,uLes of 150, 200, 250 and 300 psi, respectively. The dwell time of the product ~n the drum is about 3 o seconds .

2 ~ 86393 Wo95/27007 46 P~"~. 1149 During the partial consolidation/polymerization procedure, the decorative chips or f lakes are es~ed into and become ~mh~lrl~ in the layer of wet, tacky, ungelled plastisol.
Partial polymerization of the SARTOMER 350 and partial consolidat- on of the particle laden plastisol occurs substantially simultaneously during the consolidation/
polymerization EJL UCedUL e .
The partially consolidated product is then advanced to a series of heaters and pl ~ni ~hl~r rolls, as shown in Fig. lE, to produce a resilient inlaid floor covering product.
VE EXAMPLE I
This example is directed to inlaid surf ace coverings typical of prior art products which do not utilize a reactive plastisol adhesive. An inlaid surface covering is prepared using the pLoct-luL~:, Ls and apparatus described in Example I, except the plastisol adhesive consists essentially of about 13% by weight of calcium carbonate filler, about 26 by weight plasticizer and about 51% by weight PVC resin.
COMPARaTIVE EXAMPLE II
An inlaid surface covering is prepared using the u~eduLc ~ - ~x and apparatus described in Example I, except the plastisol adhesive consists essentially of about 40%
by weight of calcium carbonate filler; about 16% by weight plasticizer; and about 32% by weight PVC resin.
The products ~L uduc~d in accordance with each of the above r 1F'~ are tested to determine the following properties:
tensile strength; elongation; indent resistance (residual and ~ WO g~t27007 2 1 8 ~ 3 ~ 3 r~ . ,. 149 - rolling); fl~lAm;n~tion; and Taber stiffness. These results are reported in Table l below. The res~lts for Comparative Example I and Comparative Example II are identif ied in the Table by the designations CEX. I and CEX. II, respectively. Also reported in 5 Table l are test results f or a leading competitive ~ I.laid product, namely CORLON~D, produced using the stencil build-up technique. (CORLON3 is a registered trademark of AL.u.,LLu..g World Industries, Inc. ) 150 Ib-. Tab~r 151Ongll- Rollil~g Stiletto r ~ tiffn--Gaug~ T~nsil~ tion Ind-nt (l~r/72}1rs) (6000 cycl-~) (50F/73F) - l_ (mils~ ~T~ ) (mils~ ~m;lc~ IPA~s/Fa71~ U/2~
EX.I84-86 59-62 45-55 3.4 9.3/8.9 Passed 500/420 15CEX.I 85--87 23--25 130--140 6.5 12.0/11.5 F~il~d 215/185 CEX.II 84-86 17-20 100-110 5.6 11.4/11.0 Failed 245/205 CORLON~ 82--84 54--56 20--30 3.3 8.3/7.8 Passed 800/675 The above test results ~ I .ate that the inlaid surface coverings of the present invention possess highly desirable 20 physical properties, as measured by tensile :~LL~I~yL~l~
elongation, indent resistance, ~ m;n~tion and stiffness. In comparison to typical prior products which do not utilize a reactive matrix, (CEX.I and CEX.II), the surface coverings of the invention possess superior tensile, elongation, indent and 25 ~ Amin~tion properties. In addition, the present inlaid surface coverings possess superior hand as compared to the prior art surface coverings which are either excessively flexible (CEX. I and CEX. II) or excessively stiff (COr~LON3) .

Claims (33)

We claim:

1. A process for manufacturing a decorative inlaid floor covering product comprising:
(a) providing substrate means for supporting overlying layers of the product at least during the manufacture thereof;
(b) providing a reactive plastisol layer on said substrate, said reactive plastisol layer comprising reactive plastisol and a plurality of discrete, decorative elements which exhibit decorative effects at least substantially embedded in said reactive plastisol, said reactive plastisol comprising vinyl resin, plasticizer for said vinyl resin, and a reactive component;
(c) gelling said plastisol;
(d) during said gelation step (c), at least partially polymerizing said reactive component; and (e) forming a wear resistant inlaid layer by substantially fully fusing said reactive plastisol.

2. The process of claim 1 wherein said step of providing a reactive plastisol layer comprises providing a coating of said reactive plastisol on said substrate and depositing said decorative elements onto said coating.

3. The process of claim 1 wherein said decorative elements comprise decorative resinous particles.

4. The process of claim 1 wherein said reactive component comprises monomer capable of polymerizing to a thermoset polymer and wherein the weight ratio of said vinyl resin to said reactive component is from about 2:1 to about 5:1.

5. The process of claim l wherein said step of providing a reactive plastisol layer comprises providing a coating of said reactive plastisol on said substrate, depositing said decorative elements onto said coating, and substantially embedding said decorative elements into said plastisol coating.

6. The process of claim 1 wherein said plastisol comprises from about 35 to about 50 pbw of vinyl resin, from about 8 to about 12 pbw of plasticizer, and from about 8 to about 12 pbw of reactive monomer.

7. The process of claim 7 wherein said plastisol further comprises from about 0.2 to about 0.5 pbw of catalyst for catalyzing polymerization of said monomer.

8. The process of claim 1 wherein said step of at least partially polymerizing comprises heating said reactive plastisol to temperature of from about 200 to about 300°F.

9. The process of claim 8 wherein said partial polymerization comprises exposing said adhesive matrix to a rotating heated drum for a period of from about 20 to about 40 seconds.

10. The process of claim 1 wherein said vinyl resin comprises poly(vinyl chloride) resin.

11. In a process for manufacturing a decorative floor covering of the type having an inlaid wear layer comprising the steps of providing substrate means for supporting the wear layer at least during the manufacture thereof, providing the substrate with a layer of fluid plastisol composition, depositing decorative resin particles onto said layer of fluid plastisol composition to produce a particle-laden fluid plastisol layer, and fusing the particle laden plastisol layer and thereby forming an inlaid wearlayer for the floor covering, the improvement characterized by the steps comprising:
(a) forming the plastisol to comprise from about 35 to about 50 pbw of vinyl resin, from about 8 to about 12 pbw of plasticizer, from about 8 to about 12 pbw of reactive acrylate monomer, and from about 0.2 to about 0.5 catalyst for catalyzing polymerization of said monomer to produce a particle-laden reactive plastisol layer; and (b) exposing said particle-laden reactive plastisol to time, temperature and pressure conditions effective to substantially simultaneously (i) cause at least partial polymerization of said reactive monomer and (ii) cause at least partial gelation of the particle-laden plastisol layer; and (c) forming a wear resistant inlaid layer by fully fusing said particle-laden reactive plastisol and polymerizing said reactive acrylate monomer.

12. The process of Claim 11 comprising forming the plastisol to comprise from about 35 to about 45 pbw vinyl resin.

13. The process of Claim 12 comprising forming the plastisol to comprise about 41 pbw vinyl resin.

14. The process of Claim 11 wherein said vinyl resin comprises poly(vinyl chloride) resin.

15. The process of Claim 11 comprising forming the plastisol to comprise from about 9 to about 11 pbw plasticizer.

16. The process of Claim 15 comprising forming the plastisol to comprise about 12 pbw plasticizer.

17. The process of Claim 11 wherein said plasticizer comprises butyl benzyl phthalate.

18. The process of Claim 11 comprising forming the plastisol to comprise from about 9 to about 11 pbw of reactive acrylate monomer.

19. The process of Claim 18 comprising forming the plastisol to comprise about 10 pbw of reactive acrylate monomer.

20. The process of Claim 11 wherein said monomer comprises 1,6-hexanediol dimethacrylate.

21. The process of Claim 11 wherein said monomer comprises trimethylolpropane trimethacrylate.

22. The process of Claim 11 wherein said catalyst comprises peroxy ester catalyst.

23. The process of Claim 22 wherein said catalyst comprises t-butyl peroxybenzoate.

24. A resilient inlaid floor covering comprising an inlaid layer comprising an interpenetrating polymer network and a plurality of decorative elements at least partially embedded in said interpenetrating polymer network.

25. The inlaid floor covering of claim 24 wherein said interpenetrating polymer network comprises at least a first thermoplastic polymer and at least one thermoset polymer.

26. The inlaid floor covering of claim 25 wherein said floor covering has a rolling indentation resistance of no greater than about 5 mils.

27. The inlaid floor covering of claim 25 wherein: said floor covering has a stiletto indentation resistance of no greater than about 10 mils.

28. The inlaid floor covering of claim 25 wherein said floor covering has a tensile strength of at least about 30 pounds and an elongation of greater than about 25% and less than about 60%.

29. The floor covering of claim 25 wherein said floor covering has a rolling indentation resistance of no greater than about 5 mils, a stiletto indentation resistance of no greater than about 10 mils, a tensile strength of at least about 30 pounds, and an elongation of from about 25% to about 60%.

30. The inlaid floor covering of claim 25 wherein said floor covering has a Taber stiffness of no greater than about 600.

31. The inlaid floor covering of claim 25 wherein said thermoplastic polymer comprises poly(viny chloride).

32. The inlaid floor covering of claim 31 wherein said poly(vinyl chloride) comprises plasticized poly(vinyl chloride).

33. The inlaid floor covering of claim 25 wherein said thermoset polymer comprises acrylic polymer.