CA1058982A - Method for installing carpeting and thermoplastic adhesive tape therefor - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
Carpet and other types of covering are installed by a method using thermoplastic adhesive tape in a strip-like form with a substrate according to one form including an electrically conductive metal to carry a layer of hot melt adhesive at one or both of its sides. In a second form the substrate carries parallel tracks of thermoplastic adhesive which includes an electrically conductive pigment and/or resin. The adhesive is heated to a bonding temper-ature by passage of a low voltage electric current through the electrically conductive substrate and/or conductive materials in the adhesive. In one aspect, the adhesive is heated to form a carpet seam by placing the tape to under-lie abutted edges of carpet. A paper backing is located on the adhesive at the remaining side to avoid bonding the tape to the floor. In a second aspect, the adhesive tape is used to bond a covering to a support surface. In a third aspect, heating of the thermoplastic adhesive is carried out to bond a nailing strip to the floor after which the nailing strip is used to anchor an edge of the carpet.

Description

~ S8~ ~Z `-A MEDH~D FOR INSTALLING CARPETING AND
THERMOPLASTIC ADHESIVE TAPE THEREFOR - :
The present înve~tion relates to an improved method and thermopla~tic adhes~ve tape or adhering cover~
ing material to a support surfaceO M~re particularl~ ~he ins~allation of carpe~ whereln as ~n incident to the ins~al~
lation, adjacent and abut~ing pieces o carpet are seamed together by me~ns of the tape positioned to underlie the two carpet pieces along ~he abutting marginal zone thereo~
to ~hereby present a generally seamless appearance when ~ .
~: viewing from the fa e of the carpet as it lays on the floorO
, The thermoplastic tape is further useul ~o bond carpet to ,~
i ~loor, eO~O a concre~e floorO The present inven~ion is :~
also addressed to a method of and tape assembly ~or bo~ding `
tackin~ strip~ about the periphe~.~ of a ~o ~ so that the '~
carpet can be anchored to the nai:Ling stripsO The present .
invention specifically pr~vide~ a~n adhesive ~ape including :.
a~hot melt adhesive and a method ~or heating the adhesi~e :to a bonding temperature u~ing re~is~ance heating of an 20 ~ electrically conductive means included as pnrt o~ a substrate or the adhesiveO
i Hot melt adhesive ~ape is currently used in the carpet industry to ~e~m abut~ing edge~ of two pieces of ~ ~ .
. carpe~ togetherO The adhesive tape consists o a kraft paper backing with a film o~ hot melt adhesive ~o secure a .1 ,`:, .':

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iberglass reinforcing strip ~o the kraft paper backing.
Hot melt adhesive, in a continuous pattern, is deposited along ~he upper surfa~e o~ the reinforcing fiberglass str~pO The adhesive, in the continuous pattern, is re:melted just prior to its application to the adjacent marginal zones a~ the backs o ~he ~wo carpet pieces for seaming them ~oge~herO This is ~ccomplished by progressively moving an elertric iro~ or direoting hot air from a blower along the tape to melt the adhesive, and then progressively positioning the carpet edges and pressing the marginal zones at the baeks of the carpet on~o the ~wo halves of the tape so that when -, ~.
the melted adhesive resolidifies~ i~ will unite ~he backs o~ the carpe~ togetherO mis u~e of 8n electric iron or ` ~ ~ .
hot air blower is haæardous and awkward. These operations require great skill by ~he in~taller because he must know at wha~ ra~e ~he electric iron or blower ~hould be mo~ed along the tape in order to heat the hot melt adh~s~ve ~o a `~
su~icient temperature which wiLL insure its full use as a ~ :`
~hermoplastic adhesive to form a bond~ The bond must be a high integrity in order to assure ~he succes~ful use of the tape. .
Heating the ~ape is very critical and the instal~
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ler must take in~o considera~ion not o~ly ~he available heat supply ~rom ~he iron or blower but also the am~ient temper-ature in the room and the temperature of the tape itselfO

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The use o~ an lron to hea~ the ho~ mel~ adhesive i5 - cumbersome operationO The iron mu~t be inserted between ~he two pieces of carpe~ing and then moved orward along the tape for a distance o~ approxima~aly 2 to 3 fee~O Thls distance is usually de~ermined by the installer~s skill to predict the period of time at which the adhe~ve will remain ..
at an open temperature ~or bonding upon coolingO The car~
pet installer must then retrace his pa~h back along ~he se~m of the carpet and abut the carpe~ pieces ~ogether while pressing them again~t the tape as he returnsO The installer :
is severely restricted as to the speed at which he can per~
. ~orm ~hese operationq because if too many fee~ o adhesive .
i. have been he~ted to a bonding t~mperature, then the adhes~ve . will solidiy be~ore he can co~plete the bonding o ~he :: ;
carpet edgesO During these operations there is the potential : danger of burni~g ~he ca~peting due to an accidental mis :', .;- ;
placement of the iron as well as burning ~he carpeting at ~ the seam line between the pieces of csrpeti~gO Alsoj~ the `:~
,~ installer may incur severe burns by accidental contact with ~ :-the ironj~ par~icularly in li~ht of his required quick move~
ments to per~orm the carpet seaming operationsO Afte~ the ~'! adhesive has cooled, it is practically impossible to adjust or reposition the carpet sh~uld this be ~ecessary or desir~
able. -~

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~, . A method of bonding together abutting edges of carpeting with carpet seaming tape along a . :
seam line at a surface of the carpet which faces toward a support surface for the carpet, the method :-: :
including the steps of selecting a desired length of carpet seaming tape which essentially includes a layer of thermoplastic adhesive extending partly along only one face surface of a heater strip forming part of a substrate having an exposed marginal edge ;~
thereof at each side of the layer of thermoplastic adhesive to receive heated adhesive when displaced .
as an incident to the carpet being urged into con~
tact with the layer of adhesive, locating the selected length of carpet seaming tape to extend along the support surface, abutting the edges of the carpet to . ~, ., -. ~. ~
~!~ : : form a seam line extending along in an overlying ~: relation with the carpet se~ning tape such that the layer of thermoplastic adhesive contacts the back surface of the carpet only along marginal edges at : each side of the seam line, connecting electrical ~ leads to a low voltage power supply to an exposed ::~ marginal edge of the heater strip across the length .: : :
of carpet seaming tape to be heated, controllably ~ - -.j :- ~ .
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limiting the passage of an electrical current along the heater strip through an adjustable current limiting control to produce resistance ~ :
heating thereof and thereby heat the layer of thermo- ; :
plastic adhesive, maintaining the resistance heating to provide a controllably selected open time during ~;
which the thermoplastic adhesive is non-functional, maintaining the carpet in contact with the thermo~
: plastic adhesive during heating thereof, ad~usting the position of the abutting edges of the carpet ~ along the entire seam line into a desired aligned ~ ~ relation therehetween during the open time, there~
after discontinuing the resistance heating to allow the thermoplastic adhesive to cool to an :~ : ambient temperature and thereby bonding together the ~ ~ `
abutting edges of carpeting with seaming tape, and disconnecting the electrical leads from the exposed ~: marginal edge of the heater strip after the dis~
continuing resistance heating.
: ~ These features and advantages of the : present invention as well as others will be more fully understood when the following description is " , read in light of the accompanying drawlngs~ in : ~ which~
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Figure 1 is a partial plan view with broken away portions to illustrate portions of a thermoplastic adhesive tape embodying the features of the present invention and including the method of seaming carpet pieces during their installation;
Fig. 2 is a sectional view taken along line II-II of Fig. l;
Fig. 3 is a partial plan view similar to j~ Fig. 1 but illustrating thermoplastic adhesive tape -~
J , for securing a tack strip to the floor;
Fig. 4 is a sectionaI view taken along line IV-IV of Fig. 3;
-, ~ Fig. S is a partial plan view similar to Fig. 1 but illustrating another form of thermo-~ plastic adhesive tape according to the present 3~ ~ invention; ' , .

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" , , Figo 6 is a par~ial plan view similar tc> Figo 1 but illustrating another ~o~m of ~hermoplas~lc adhesive .
~ape according ~o the present i~en~ion;
Figo 7 is a sectional v-Lew ~aken along Lines VII-VII of Figo 6;
Figo 8 is a seetional view similar to Fi~o 7 `
but illustra~es a diferent form of ~he present ~nventionO
The thermoplastic adhesive ~ape illustrated in igæO 1 and 2 is adap~ed to seam together a7but~ing edges of two piece~ of carpetingO It is preferred to construct ~:
this ~ape in a maNner such that i~ can be handled and `~
transported in ~he form of a roll of tapeO Each roll will ., ~, preferably inelude a leng~h o~ tape of 15 fee~ or some muLtiple of ~bis length for maximum compatibility with ~he .. :~
standard widths of Farpet prese~ly available in the industryO me length of tape which is removed from the -~
roll will be select~d so that i~ will extend along ~he full;`~
length of~abutted edges of carpet to be seamed togetherO
~s illustrated in Figs~ 1 and 2, the ~hermoplas~ic adhesive tape 10 includes a krat paper backing 11 which is in a strip-l~ke form and receives on its one surface, a ~hin film or Layer o~ thermoplas~ic adhesive 120 The adhesive 12 and paper backing Ll form part of a substrate that further -~
includes an overlying strip-like length of metallic screen or wire m2sh 130 The wire mesh is actually bond~d by the -7- ;

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~ 58~ 82 adhesive layer 12 to the backing strip 11, thereby providing a metallic reinforcing member for an overlying l~ya~ of thermoplastic adhesive~ The size of the wire mesh may be as s~all as mPsh s~ze 3~5 and as large as a mesh size of 80 or even a mesh size o 30 The mesh size and wire dia- -meter represent variables afecting ~he quantity of heat .
produced by resistance hea~ing to meIt the thermoplastic adhesive an~ mus~ be selected accordingly The upper surface of the wire mesh receives a `~
layer o thenmoplastic adhesive 14 preferably in the form of 6 to 8 spaced-apart tracks or beadis of thermoplastic adhesive which extend in ~he d~rection of the tape length and spaced inwardLy from its longitudinal edges approximately :, :: ,;
1 inch so that w~en the a & esive is heated to a bonding ~em- ~:h perature and a marginal edge of carpeting ls pressed onto ,. i , . , the adhesive9 the adhesive will not inadvertently flow beyond the edge of the tape i~to c~ontact with the floor Instead of employing a wir~ mesh, as will be explained in greater detail hereinafter, a strip of expanded me~al~ a ~ .
st~ip of perforated metal or a plurality of spaced parallel -wires with a~ adhesl~e coating may be used as both a reinforcing member and as a means for electrically heating .
": . ' a fina~e length o the adhesive tapeO Moreover, ~he thermoplastic adhesive can be compounded so that i~ is ~ ?
eLectrically conductiveO The adhesive layers L2 and 14 -~

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as well as the adhesive layers to be described hPreinafter ln regard to Figs~ 3 and 4 should be selecte o a material ~hat is s~rong, ~ha~ ages well, and will not damage the ~loor sur~aceO The adhesive 8hould be resiYtant to cleaning ma~erialsO The preferred adhesive is a thermoplastic, high viscosity ethylene-vinyl acetate copolymer modified with paraffin wax, an antioxidant and a plasticizing re8in~ The sof~e~ing point of th~s adhesive is 65C and it has a crack-ing point below 0C~ Such an adhesive is ma~ufac~ured by Gateway Pain~ and Chemical Company of Pit~sburgh, PaO ~ -~
Fig. 2 ilLustrates the location of the adhesive ,:
tape 10 upon the top surfac~ of a carpet pad 15 in relation to two pieces o carpetn If the carpet ha~ a pad adhered to ~: it, then the tape 10 will underli~! both the carpet and pad~
Di~ided pieces of carpet 16 are shown with an edge o~ each .
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positio~ed into an a~utted relatic)n to form a seamline at 17. I~ i8 intended, however, tha1: a~ter the pieces of carpet .`~ :
: are bonded together with the tape 10, that the seamline 17 will be generaLly invisible when viewed from the top su~ace .
~: 20 of th~ carpetingO ~ ~ ~After ~he sel~cted length of adhesi~e tape 10 is ~ : :
placed on the pad or ~loor, the two pieces o~ carpe~ing are ;~ :
brought into an abutting xelation defining the seamline 17 which is orien~ed in regard to the adhesive strip so ~ha~ two `~
marg~nal zones at either side of the seamline at the backs of th~ caxpet ov~rlie ~he two or more ribs of the thermoplastic _9~

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, ~L~58'.'.3i~f'2 adhesive 140 In the event, the thermopl~stic adhesive layer 14 i9 deposited as a continuous s~rip-like layer, then the tape i3 oriented so that the seamline 17 extends approximately midway between ~he longitudlnal edges of the tape~ As indicated prevlously, it is intended that the length of tape be selected so that it extends along - the length of the seam to be formed between two pieces of carpetO Thu , for e~ample, when two 15-foot wide pieces of carpet are to be joined together, then ~he l ~gth of ;~ 10 taye selected would be 15 feet longO After the carpeting ::~
:- and tape have been loca~ed as just described, then a lead ~s .,: ~:
wire 20 ls connected by way of a~ alligator clip 20A into : .
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electrical contact with the metal reinforcing wire mesh 13 `~ at one end o~ the tape and a lead wire 21 is connected by an ~:~ alliga~or clip 2L~ to the metal reinforcing wire mesh 13 at ~he othçr e~d of the ~apeO The le3ad wires 20 and 21 areJ
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in turn, connec~ed to the output ~:erminals of a powar supply 22 including a step-down transormerO The power supply is of a conventional well-lcnown constructionO It ~:
20 ~ receives, ~or e~ample, a 120-volt alkernating cur~ent to p~ovide an ou~pu~ of 16 vol~s in the leads 20 and 2L at a-ma~imum cur~ent o~ 100 amperes for example. M4reover, the -rating of the power 9upply shouLd be of ~he order of 1-1/2: ;
kilovol~ amperes and includes a current limiting adjustmen~
control whereby an operator may control ~he resis~ance heatlng o~ w~re mesh and the adhesive s~rip in a dependent ~10~

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relation to the actual length o the thermoplastic adhesive tapeO
Figs. 3 and 4 lllustra~e a second embodiment of the presen~ in~en~ion wherein a thermoplastic adhesi~e ~ape 30 is used to bond a tac~ strip 31 to the 1Oor ~bo~t the p~rimeter o the axea to be carpeted~ This mann~r o att~chment is partlcularly advantageous in circumstances where nail~ng is prohibited by reason of, or example, a concre~e floor or llmi~ed access to the area~ The presen~ `-invention is additionally useful for securing ~acking strlps in an accelerated manner over that which can be accomplished by a conven~ional nailing techniqueO The adhesi~e s~rip 30 includes a reinforGing metallic wir~
mesh 32 onto which at its opposi~e sides, there is deposited .: .- .
.~:: a top and bottom layer of th~rmoplastic adhesive 33 and 34 :respectively. .~

According to the embodiment illustrated in Figs. ~;

:: 3 and 49 the reinforclng metallic wire me h 32 along with : ~: .. ., - -one of the layers of thenmoplastic adhesive 33 and 34 define the sub~trate carrying ~he remaining layer o ~he : thenmoplastic adheslve 33 or 34O The adhesive strip 30 is intended for handling and transporting in a coiI-fonm, whereby at the job site, the coil is uncoiled and a ~elected length of strip i~ cut from the coil~ The strip is then -~: . , positioned wi~h a ~hermoplas~ic adhesive layer in contact , ~`

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wlth the floor adjacent ~ wall 3~O It i5 preferred that straight continuous lengths of the adhsslve strip 30 should be electrically heated using the p4wer supply 22 in the manner already described in regard to Fi~so 1 and 20 Prior to hea~ing of the thermoplastic adhesive strip, a nail strip 37 is positioned on the top layer of thermoplastic adhesive follow:Lng ~hich the electric cur- .
rent is passed through the reinforcing metallic wire mesh to produce resistance he~ting thereof" The heating is maintained for su~ficien~ period of time to hea~ both -layers of thermoplastic adhesive 33 and 34 to a bo~ding temperature with a controlled open timeO -The expression "open tima" as used herein refers ~o a period o~ ~ime during which the thermoplastic adhes_ :
ive is nonfunctionalO The open tLme is, therefore, con- :
trolled according to ~he present invention and may be .
: extended by the agency of electrical heatingO The adhesive ;: ~:
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: can be repe~edly reheated to acilita$e adjusting the :~
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carpet as desired or necessaryO The resistance heating is ;1~ 20 ~hen discontinued to all~w the adhesi~e ~o cool and fonm -, ~
a bonded connection between the adhesive strip 30 and the .
100r as well as the tack strip 31 and the adhesivP strip ` :
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30~. The ~cack strips may be provided with thermoplastic :~
adhesive st~ips prior ~o their posi~ioning about the per_ ~ .

iphery of a room in which everlt, a bonding due ~o the :~
electrical resistance hea~ing, will occur at 'che job site -`
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~ 5~8 between ~he bottom layex of thermoplastic adhesive and the 1OorO The adhesive tape 30 ls equally useul to bond ~
carpet dlrectly to the floorO The tape 30 can be used, or :~.
example~ to bond wall paneling dlrectly to a vertical sup~
port surfaceO ~ `
~igure 5 illustrateis a modified form of thermo- ~
plas~ic adhesive tapeO This tape lncl~des a kraft paper ~ :
backing 40 ha~ing a film or layer of ~hermopLas~ic adhes~ve 41 for adhesiveLy seeuring a ~hin metal strip ~2 along the leng~h of the tapeO The strip 42 is perforated or expanded ~. :
to form a~ array of openings 43 along the length thereofO ~:
. ~ . , ~,~ While not show~ in Figo 5~ the strip 42 may consist of aluminum foil without t~e openings 43 and bonded directly .~ ~

; to the backing 400 In Figo 5~ the metal strip is arranged . ~ --, such that the side o~ the metal s~rip with the raised and ,~
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deformed edges surrounding the openings faces toward the backing surface of the carpe~O Deposited on this roug~
e~posed surface o~ ~he metal s~rip is a layer or alter~
;. . . ~ . -natively parallel beads of thermoplastic adhesive 44O ::
The a &esive 44 is heated by passing electrie ~ ~:
current ~hrough the me~al strip 42 in the same ~anner as already described in regard ~o Figure lo I~ is apparent ' ~ ~-that the adhesive strip illustrated by Figure 5 can be modified so a~ to eliminate the u~e of the kraft paper backing 40 whereb~ a carpet, for exa~ple, can be adhered to a floor surface by electricalLy heating the adhesive : --13- ~

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cation o~ the present invention which differs from that already described essentially by providing that parallel tracks or beads 46 of ~henmoplastic adhesive are mixed with materials added to the adhesive so tha~ the beads : :
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them~elves are electrically conductive or the purpose of heating the adhesiveO To provide the~e beads or ~ ~ .
tracks of th~rmoplas~ie material, I pre~er ~o select a -~hermoplastic material as previously described to form the adhesive layers 12 and 14 and modify this material ~` -,~
by adding either a resin ~ha~ is electrically conductive or, preferably, I would modiy the adhesive material by ~:~
adding a resin and ill~ng it with a conductive material :~ such as divided metal par~icles o silver or copper ~ ~ .
typicaLly in the form of powders of these metals ~o pro~
vide electricaLly conductive medium in the form of a pigmentO mis avoids the need to use a resin which is ` : :
electrically conductiveO The adhesive with ~he added .l 20 ele~trically conductive materîals is then deposLted in ~he `~` for~n of the beads 46 upon a substrate that need not be :
electrically conducti~e and may be a rein~orcing strip of `
fiberglass webbing 47 that is adhered by an adhesive layer 48 to a kra~ paper backing 490 Again~ the kraf~ paper backing 49 can be eliminated and the adhesive layer 48 ' can be formed by the same m~terial used ~o form the beads .'1 `.
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:, " , ~ ,,, ... " , . . , , ~ ~, ~S~C~2 46 and thexeby prol,riding an adhesîve strip for adhering carpe~ or the like to a support surface by the passage of an electrical currentO
Figure 8 illustrat:es a still fur~er modified ~.
., form of the pressnt invention wherein the thermoplastic ~-~
material that was used ~o form the adhessi~e layers 12 and 13 ~ ~
sh~R~h inq ~ :
is used in the form of a ~be~h~g ~or covering SO ~hat incapsulates each of a plurality o~ electrically eonductive ::
wires 51~ These adhesively coated wires are arranged in the paralleL spaced-apart relation upon a reinforced substrate 52 that includes a nylon or fiberglass webbing 53 which is inturn adhered to a kraft paper b cking 54 by an adhesive layer 55. The wires 51 are used ~o pass an elec~ric current to heat the thermoplastic adhesive 50 .
to a bonding temperatureO The adhesive layer 55 can be -~
provided by using the adhesive coated wires at both sides .~, .
, of the reinforcing material for bonding a surface o~ a ,: ~ov~ri~g to a support sur~aceO
The present inve~tion greatly improves the me~hod ~:
, 20 ~ and tape used for forming a bonded connec~:ion incident to -:~ the installation of a covering. ~he installer can quickly :~
~ ~ position ~he adhesive ~ape at the seamline below pieces of ,s, ~ carpetlng and quickly positio~ the adhesive tape in the :; -desired relation with regard to the nailing stripO Aftcr :-' f ~ `
. the adhesive ~ape is posi~ioned the resistanceS heating of ;~ -- the thermoplastic adhesive is carried out throughout the entire selected lengtSh of the adhesive strip~ This frees :::
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the operator to assure optimum r~sults without the necessity of manually bringing ~he covering, iOeo carpet-ing or the nailing strip, into final dQsired relationshipO
Long continued integrity of the bonded connection can be assured by applying pressure to the top surface o the :~
covering a~ter the ~hermoplastic adheslve has attained a bonding temperature. .
Although the invention has been shown in ~ -sonnection with cer~ain specific embodiments, it will be readily appa~ent to those skilled in the art that various changes in form and arrangement of parts may be mQde to ~ :.
suit requirements ~ithout departing from the spirit and ,.` :~
scope o~ the inventio~O
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Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are fefined as follows:

1. A method of bonding together abutting edges of carpeting with carpet seaming tape along a seam line at the surface of the carpet which faces toward a support surface for the carpet, said method including the steps of:
selecting a desired length of carpet seaming tape which essentially includes a layer of thermoplastic adhesive extending partly along only one face surface of a heater strip forming part of a substrate having an exposed marginal edge thereof at each side of the layer of thermoplastic adhesive to receive heated adhesive when displaced as an incident to the carpet being urged into contact with the layer of adhesive, locating the selected length of carpet seaming tape to extend along said support surface, abutting the edges of the carpet to form a seam line extending along in an overlying relation with said carpet seaming tape such that said layer of thermoplastic adhesive contacts the back surface of the carpet only along marginal edges at each side of said seam line, connecting electrical leads of a low voltage power supply to an exposed marignal edge of said heater strip across the length of carpet seaming tape to be heated, controllably limiting the passage of an elec-trical current along said heater strip through an adjustable current limiting control to produce resistance heating there-of and thereby heat said layer of thermoplastic adhesive, maintaining said resistance heating to provide a controllably selected open time during which said thermoplastic adhesive is non-functional, maintaining the carpet in contact with said thermoplastic adhesive during heating thereof, adjusting the position of the abutting edges of said carpet along the entire seam line into a desired aligned relation therebetween during said open time, thereafter discontinuing said resistance heating to allow said thermoplastic adhesive to cool to an ambient temperature and thereby bonding together said abutting edges of carpeting with seaming tape, and disconnecting said electrical leads from the exposed marginal edge of said heater strip after said discontinuing resistance heating.