Note: Descriptions are shown in the official language in which they were submitted.
~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 .
393
~ 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
21 86393
~ 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.
2 1 86393
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
2 1 86393
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.
21 86393
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
21 86393
~ 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.
21 86393
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
393
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~
21 86393
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
373
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
21 86393
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.
21 86393
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. )
TABLE 1
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) .
