CA1260774A - Writable adhesive tape - Google Patents
Writable adhesive tapeInfo
- Publication number
- CA1260774A CA1260774A CA000480700A CA480700A CA1260774A CA 1260774 A CA1260774 A CA 1260774A CA 000480700 A CA000480700 A CA 000480700A CA 480700 A CA480700 A CA 480700A CA 1260774 A CA1260774 A CA 1260774A
- Authority
- CA
- Canada
- Prior art keywords
- adhesive
- weight
- tape according
- tape
- substrate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Abstract
ABSTRACT.
The writable adhesive tape has a flexible substrate, a self-sticking coating on one side thereof, and an anti-adhesive writable coating on the opposite side constituted by a film forming resin, an anti-adhesive agent, and a matting agent.
The substrate is selected from oriented and non-oriented films of alpha-olefine polymers and co-polymers having at least the side bearing the anti-adhesive coating free from any additional priming layer and adhesion promoting surface treatment. The anti-adhesive writable coating comprises from 25% to 55% by weight of at least one chlorinated polyolefine and from 20% to 50% by weight of a polyaldehyde resin as a film forming resin and as a substrate adhesive promoter resin, together with 5% to 20% by weight of an anti-adhesive agent, and 5% to 25% by weight of a matting charge.
The writable adhesive tape has a flexible substrate, a self-sticking coating on one side thereof, and an anti-adhesive writable coating on the opposite side constituted by a film forming resin, an anti-adhesive agent, and a matting agent.
The substrate is selected from oriented and non-oriented films of alpha-olefine polymers and co-polymers having at least the side bearing the anti-adhesive coating free from any additional priming layer and adhesion promoting surface treatment. The anti-adhesive writable coating comprises from 25% to 55% by weight of at least one chlorinated polyolefine and from 20% to 50% by weight of a polyaldehyde resin as a film forming resin and as a substrate adhesive promoter resin, together with 5% to 20% by weight of an anti-adhesive agent, and 5% to 25% by weight of a matting charge.
Description
~ ia in~rention relates to a ~qritable hdhe~i~re tape.
Curr~rltly knor~ a:re adhe~ive tap~s which compri~3e a ~ub~trate~ mo8tl;y form~d ~rom a ~lexible pla~tic material, hav~ng on o~e ~ide a coati~g or layer o~ an adhe~i~e wh~ch, in u~a, adhe~ whs~ applied ~ith a ~light pressure, i.e~, an adhe~iYe la~er~ a~d ~ the oppo~lte ~ide a~ a~ti-~ldhesi.ve coati~g or layer whi~h ia al~o ~uited ~o be written or printed u?orl (the 10 term "writE~blen ~,nill be u~ed herei~after ~or brevity) by means o~ arur ordinary writing or pr~nting mean~, In fact, that coa~ing~w~ioh ha~ in such tapes the function o~ a ~ritabl~ layer i9 ~ IBO required to per~orm a~ ~ti-adhe3~:ve or '~elsa~e~ function ~relea~e coati~g)9 15 ThiEI becaul3e ad~esi~e tapes are mostly sold in the ~orm of rolls w~erein the tack~ side contaet~, owi~g to the rol~ing up~ the juxtaposed writabl8 0id~ .
order ~or the tape to be ea8ily us~olled
Curr~rltly knor~ a:re adhe~ive tap~s which compri~3e a ~ub~trate~ mo8tl;y form~d ~rom a ~lexible pla~tic material, hav~ng on o~e ~ide a coati~g or layer o~ an adhe~i~e wh~ch, in u~a, adhe~ whs~ applied ~ith a ~light pressure, i.e~, an adhe~iYe la~er~ a~d ~ the oppo~lte ~ide a~ a~ti-~ldhesi.ve coati~g or layer whi~h ia al~o ~uited ~o be written or printed u?orl (the 10 term "writE~blen ~,nill be u~ed herei~after ~or brevity) by means o~ arur ordinary writing or pr~nting mean~, In fact, that coa~ing~w~ioh ha~ in such tapes the function o~ a ~ritabl~ layer i9 ~ IBO required to per~orm a~ ~ti-adhe3~:ve or '~elsa~e~ function ~relea~e coati~g)9 15 ThiEI becaul3e ad~esi~e tapes are mostly sold in the ~orm of rolls w~erein the tack~ side contaet~, owi~g to the rol~ing up~ the juxtaposed writabl8 0id~ .
order ~or the tape to be ea8ily us~olled
2~ without dams,~e to the tape it9eL~, it i~l ~ace~ary to pre~ent ~h~ writable ~id~ ~aoing the . adheaive "la~rer" from 8'tiC3~i~ to the latter, i~,e. to ma~e ~t adhesion-pr~r~ti~gO
~ Sever~ able sel~-~ti.o}~l~g (adhe~i~re )tap~ ve b~
25 sugg~3ted in the pa~t~ ~rhich dif~er from one another by the ~a~ure of the compo~ent~ which m~:e up the su~trate9 adhe~i~e la~er9 ~d a~ti~esi~e layer9 a~
~vell as bg the ~ature of tha m~a~& utilisGed to mal~
th~ ~ti-adhe~ er ~a~Le,, Tn general~ th0 a;nti~adh~
30 d~ la~er i~ made ~ita~Le ~r rou~g or matting it by mechanical mean~ or by incorporating therein some ~illere, e.g. mineral fillers.
~ apes have been ~ugge9ted ~or example, wherein the anti-adhe~i~e wribable layer i~cluded a polyuretha~e resin a~ a gilm-generating re~in, and an an~i~sdhesi~e and matting agent (~ee US Patent No. 4138527). ~aid patent mentions polyvinylchloride as a pre~erred sub~trate for ~he ~uggested ~el~-stiok~n~ tape, although it also discloses ~ome other aUl~b~ ~.~bstrates, such as polypropylene.
However, ~e have experimentally ascertained that, on a polypropylene substrate, the release or an~i-adhesive layer taught by the aforementioned US patent was inadequately sec~, and ~he risk exi~ted that9 upon unr`o~ng the tape, ~aid anti~Qdhesive layer might be stripped o~ the sub~trate, thus making the tape unusable.
Briti~h Patent Application~ ~o. 2103513 discloses a writable adhesi~e tape, wherein, on 2 polyprop~lene ZO sub~trate9 a ~ritable layer is applied which again comprises polypropylene incorporating ~ine particl0s of an inorganic filler. In thi~ particular in~tanca, therefore, a secure bond between the writable l ayer and polypropylene substrate ~as achieved b~ u~in~ the poly-propylene itself as a ~ilm-generating resin in the writable layer as well.
Further sel~-sticking tape~ have been ~ugge3ted comprising, as ths anti-adhe~i~e coatin~ suited to : be marked a~ by writing or printing, a ~ilm generating ;
~ 26 ~7~
resin~ in particular a polyester reain, a polyketone re~in meant to imp~rt print~bility~ and conventional anti-adhesive agents (US Patent No. 4070523)o The self-sticking coatings reco~mended hereto~ore for writable self-~ticking tape~, ha~e the di~advantage of being dif~icult to use with olefinic polymer substrates which haYe not been previou~ly coated, on the back side intended to reoeive the anti-adhes1ve agent, with a bonding or primer layer, or ha~e not been subjected, on that same side, to a sur~ace treatment of the chemical or electronic type ~corona effect, flame treatment, etc.). This hold~
particularly true for polypropylene substrate tape~ OW~Dg to the inadequate bonding that can be obtai~ed bet~een known compositions for the anti-~dhe~i~e writable coating and polypropyleneO
It is a primary object of this invention to provide a sol~-~ticki~g tape that can be e~sily written upon and unrolled, while economically advantageous.
In particular~ it is an object of the in~ention to pro~ide a ~elf-sticki~g tape having an anti-~dhe~ive wri~able layer that can be very well secured to an economically adva~ ~ polyolefinic substrate.
A ~urther object of thiR invention i~ to provide a sel~-stic~ing tape o~ the ~pe mentio~ed ~bove 9 which requires no addition&l p~ing layers, nor any ~urface treatment of the chemical~ electronic~ or flame type to ensure integrity o~ its structure.
These and oth~r object~, such as will be apparent , .
' ~
~ 7 7 ~
hereinaf~er, are achieved by a self-sticking tape .
according to the invention, which eomprises a flexible plastic material ~ub~trate~ a ~el~-sticking coating on one ~ide thereo~, a~d an anti-adhe~ive writable coating on the opposite side, characterized in that said ~ub~trate i~ ~elected ~rom oriented and non-oriented films of slpha-olefine polymers and copolymers, and said anti-adhe~ive ~ritable coating comprises at lea t one chlorinated polyole~ine and a polyaldehyde resin as the film ~orming and the adhe~ive promoters to the sub~trate~ along with at least one anti-adhesive agent and at lea~t one matt~ a~ent~
It has, in ~actS been ~ound that the simultaneou~
presence, ~n the antl-adbesi~e la~er o~ the in~ren~re tape, 15 of the chlorinated polyolefine and polyaldehydic re~in, con~ers to ~aid layer optimum film~orming and bonding properties toward the polyolefinic ~ub~trate~ ~uch a8 not to jeopardize the t~pe integrlty whe~ unrol~ing even in ths absence of any further 20 bonding layer or treatment. Furthermore, the anti-aahe~ re layer of the inventi~o tape, incorporati~g the aforesaid anti-adhe~ re and~ mattlng agent~9 gho7~3 a hi~h degree of ~ifor~ity both in appe~rance and writabillty or printability, which remains u~altered after the tape has been ~ound and unwound in use.
It has al90 been ~ound that the tape of this in~ention ~ psr~ ly ad~antageous a~so wnth helio-graphic printing techniques, where it affords a hi~h quality printing. ~oreo~er, the tape pro~ed to ha~e
~ Sever~ able sel~-~ti.o}~l~g (adhe~i~re )tap~ ve b~
25 sugg~3ted in the pa~t~ ~rhich dif~er from one another by the ~a~ure of the compo~ent~ which m~:e up the su~trate9 adhe~i~e la~er9 ~d a~ti~esi~e layer9 a~
~vell as bg the ~ature of tha m~a~& utilisGed to mal~
th~ ~ti-adhe~ er ~a~Le,, Tn general~ th0 a;nti~adh~
30 d~ la~er i~ made ~ita~Le ~r rou~g or matting it by mechanical mean~ or by incorporating therein some ~illere, e.g. mineral fillers.
~ apes have been ~ugge9ted ~or example, wherein the anti-adhe~i~e wribable layer i~cluded a polyuretha~e resin a~ a gilm-generating re~in, and an an~i~sdhesi~e and matting agent (~ee US Patent No. 4138527). ~aid patent mentions polyvinylchloride as a pre~erred sub~trate for ~he ~uggested ~el~-stiok~n~ tape, although it also discloses ~ome other aUl~b~ ~.~bstrates, such as polypropylene.
However, ~e have experimentally ascertained that, on a polypropylene substrate, the release or an~i-adhesive layer taught by the aforementioned US patent was inadequately sec~, and ~he risk exi~ted that9 upon unr`o~ng the tape, ~aid anti~Qdhesive layer might be stripped o~ the sub~trate, thus making the tape unusable.
Briti~h Patent Application~ ~o. 2103513 discloses a writable adhesi~e tape, wherein, on 2 polyprop~lene ZO sub~trate9 a ~ritable layer is applied which again comprises polypropylene incorporating ~ine particl0s of an inorganic filler. In thi~ particular in~tanca, therefore, a secure bond between the writable l ayer and polypropylene substrate ~as achieved b~ u~in~ the poly-propylene itself as a ~ilm-generating resin in the writable layer as well.
Further sel~-sticking tape~ have been ~ugge3ted comprising, as ths anti-adhe~i~e coatin~ suited to : be marked a~ by writing or printing, a ~ilm generating ;
~ 26 ~7~
resin~ in particular a polyester reain, a polyketone re~in meant to imp~rt print~bility~ and conventional anti-adhesive agents (US Patent No. 4070523)o The self-sticking coatings reco~mended hereto~ore for writable self-~ticking tape~, ha~e the di~advantage of being dif~icult to use with olefinic polymer substrates which haYe not been previou~ly coated, on the back side intended to reoeive the anti-adhes1ve agent, with a bonding or primer layer, or ha~e not been subjected, on that same side, to a sur~ace treatment of the chemical or electronic type ~corona effect, flame treatment, etc.). This hold~
particularly true for polypropylene substrate tape~ OW~Dg to the inadequate bonding that can be obtai~ed bet~een known compositions for the anti-~dhe~i~e writable coating and polypropyleneO
It is a primary object of this invention to provide a sol~-~ticki~g tape that can be e~sily written upon and unrolled, while economically advantageous.
In particular~ it is an object of the in~ention to pro~ide a ~elf-sticki~g tape having an anti-~dhe~ive wri~able layer that can be very well secured to an economically adva~ ~ polyolefinic substrate.
A ~urther object of thiR invention i~ to provide a sel~-stic~ing tape o~ the ~pe mentio~ed ~bove 9 which requires no addition&l p~ing layers, nor any ~urface treatment of the chemical~ electronic~ or flame type to ensure integrity o~ its structure.
These and oth~r object~, such as will be apparent , .
' ~
~ 7 7 ~
hereinaf~er, are achieved by a self-sticking tape .
according to the invention, which eomprises a flexible plastic material ~ub~trate~ a ~el~-sticking coating on one ~ide thereo~, a~d an anti-adhe~ive writable coating on the opposite side, characterized in that said ~ub~trate i~ ~elected ~rom oriented and non-oriented films of slpha-olefine polymers and copolymers, and said anti-adhe~ive ~ritable coating comprises at lea t one chlorinated polyole~ine and a polyaldehyde resin as the film ~orming and the adhe~ive promoters to the sub~trate~ along with at least one anti-adhesive agent and at lea~t one matt~ a~ent~
It has, in ~actS been ~ound that the simultaneou~
presence, ~n the antl-adbesi~e la~er o~ the in~ren~re tape, 15 of the chlorinated polyolefine and polyaldehydic re~in, con~ers to ~aid layer optimum film~orming and bonding properties toward the polyolefinic ~ub~trate~ ~uch a8 not to jeopardize the t~pe integrlty whe~ unrol~ing even in ths absence of any further 20 bonding layer or treatment. Furthermore, the anti-aahe~ re layer of the inventi~o tape, incorporati~g the aforesaid anti-adhe~ re and~ mattlng agent~9 gho7~3 a hi~h degree of ~ifor~ity both in appe~rance and writabillty or printability, which remains u~altered after the tape has been ~ound and unwound in use.
It has al90 been ~ound that the tape of this in~ention ~ psr~ ly ad~antageous a~so wnth helio-graphic printing techniques, where it affords a hi~h quality printing. ~oreo~er, the tape pro~ed to ha~e
3 profitable easy tear properties in the tr~sver~al .. ~
774~
direction, which greatly facilitates its use in practical usual applications.
The chlorinated polyolefine which may be used in the tape of this invention, may be any homopolymer or copolymer polyolefine having a chlorine content in the 15% to 65%
range, or mixtures thereof, and a suitable molecular weight for film formation, a Brookfield viscosity preferably in the to 180 centipoises range and a specific gravity at 25/25C preferably in the 0.850 to 0.950 range, for 25%
solutions in xylene. By way of example, chlorinated polyolefines may be used which are available commercially under the trademark CP 343, produced by Eastman Kodak, U.S.A., or trademark HARDLEN, produced by Toyo Kasey Kogyo, Japan, under the trademark TRAPYLEN, produced by Rowa, Germany. The chlorinated polyolefine varies in amount from 25% to 55%, preferably 35% to 40~ by weight relative to the overall weight (dry) of the anti-adhesive layer componen-ts in the final product.
A usable polyaldehyde resin may be any polyaldehyde resin obtained by reaction of a 4-to-8 carbon atoms, linear or branched chain aliphatic aldehyde such as isobutylaldehyde with urea. Among the ~uitable polyaldehydes is the one available from BASF under the trademark LAROPAL
8652. The u~able amount of polyaldheyde ranges from 20% to 50%, preferably 30% to 40% by dry weight.
In addition to the two film-forming resins used in the anti-adhesive writable layer of the tape of this invention, the layer may include, according to tï
.
.. . .
;
' ~'~"' '~ '' ' :.
~6~77 ~ 6 alternatiYe embodiments of the invention, further re3in componentis.
~us~ ~ccording to ~nother embodiment of the anti-adhesive ~!vritable layer, tl~is comprises 25y to 59~ju of said chlorinated polyole~ine7 15~ to 30p of ~sid polyaldehgde, together with 5~ to 20~ o:E a linear elastomeric polyuretha~e as film~:I'oxmir~
resins~ in addition to said anti-adhesi~e agent ~nd ~aid mattlng ager~t.
~referably, for the film-form~g and bonding resins, the follo~ing proportions are used in this embodimelt: 35,~ to 406jo chaorinated polyole$i~, 20jo to ; 2550 pol~aldehyde, and 10C/~ to 1570 polyurethane.
The usable polyurethane i~ a linear elastomeric ', 15 polyurethane ha~ing preferably a high crystallinity.
I As an example, a polyurethane ob~ained by reacting a i polyester having end hydroxyl group~ as deri~ed from a dicarboxylic acid o~ 4 to 10 carbon atoms and a diol of 4 to 10 carbon~i, with æn aliphatic or 2a aromatic di-isocyanate, ma~ be u~ed. Also a polyester obtained by the reaction of adipic acid with hexanediol and then cross-linked with toluene-di-isocyan~te, may be u~ed.
By way of exemiple9 c.~iable polyurethane i~ the one available from BASF under the trademark of lUsi~E;~
142~.
: ~he anti-3dhe~1~e ~unctio~ ia proYided by lncorporat-ing,q~to the anti-~dhesi~e l~yer ~ the inventive tape, ~n ~: anti-adhe~i~e or rel~aQe agent ~elected from thoRe 3 con~en~ionally utili~ed ~or t~e ~ame pu~po~e. Among ,"., .
lZ60774 such agents may be mentioned the polyvinylalkylcarbamates, e.g. polyvinyloctadecylcarbammate, the alkyilurethane of polyvivylalcohols, and the amides of fatty acids and polyethyleneimine. The anti-adhesive agent is used in amounts ranging from 5~ to 2Q%, preferably 10~ to 15% by weight of the overall weight of the components in the anti-adhe~ive layer.
The anti-adhesive layer is made writable by the incorporation of a matting agent, in accordance with conventional techniques. As the matting agent, an inorganic material may be used in the form of finely divided particles, such as talc, silica, calcium carbonate, etc., a high purity silica being preferredfor instance the high purity ~ilica available under the trademark SYLOYD from W.R.Grace, U.S.A.. The dulling filler should be used in amounts ranging from 5% to 25, preferably 10% to 15~, by weight of the overall dry weight of the anti-adhesive layer components.
The substrate to be used in the tape according to the invention is an olefinic homopolymer or copolymer,such a~
polyethylene, polypropylene, or copolymers thereof. The invention has shown to be specially advantageous with polypropylene substrates. The substrate may be uni-oriented, bi-oriented, or unoriented.
When cutting the final product into small rolls, the tape edges are made easy to cut in the transversal direction,both manually and through automatic or manual dispensers, by creating micro-indentations which facilitate starting of the crosswise cut. The micro-indentations are formed, in , ~ ~6~7~
conformity with con~entional techniques, by mean~ of cutting blades, usually termed l'score cutting".
~ he adhesive layer of the tape of this invention is ~ormed with adhe~i~e products conventionally employed with such tapeR, like an adhesive material includi~g acrylic, polyuretha~e, or polyester copolymers, or natural or synthe~ic rubbers and na~unal or ~ynthetlc resins adhesives.
The tape of this invention is prepared by applying to the polyolefinic substrate the anti adhe~ve layer and adhesive layer, respectively, preferably in the form of a solution or disper~ion in ~ui~able solve~t~7 according to conventional techniques, ~nd then remoYing the solvents by evaporation. ~he a~ti-adhesive layer of this invention may be applied, ~or example, in the ~orm of a solution or dispersion in a hgdro-carbon solvent, such as toluene, by mixing 95q' to 70~ja pre~erably 85/o to 75a/o, ~f said solvent together with 5~/o to 30a/o~ preferably 15a/~ to 25/o~ o~ the mixture o~ the anti-adhesive layer component~ 9 with the u~e of such coating arrang~ents as rotogravure, wire bar (~eyer bar~, roto~ilkscreening, etc~ The thicknesses o~ the substrate ~nd of the adhesive and anti_adhesive writable ~ ayers are uncritical in the inventive tape ,.
25 U~;ually, thiclmes3e~ prefera~ly in the 25 to 40 11m ra~ge ar~ used ~o~ the ~u~ra~e7 in the 0.4 to 10 1~m ra;~ge for the anti-~dhesive la;srer, arld in the .. 18 to 32 ~m range for the adhesive layer.
The re~ulting adhesi~e ~ape ig easil~ ~nwou~d, , - ' . .
~ ~6 ~7 adheres perfectly to di~ferént surfaces~ become~
perf~ctly transparent on application, may be photo-copied, i6 specially suitable for heliograp~ic duplication a~ practiced in the workrooms of engineering draftsmen, i8 unalterab}e with time, and iB writQble by ~11 ordinary writing methods, and in particular, with all types of pencils.
~ he Example which follows iB gi~en by ~ay of ~llu~tra-tion, so as to make the in~ention more clearly understood~
and i~ ~pt to be con~trued as l~mitlng the scopeo~ ~he ~nventlon.
Exam~
The following compone~ts are mixed together in a fast mixer of the blade type7 according to known techniques~ in toluene a3 a sol~ent~ While heating gradu-ally to 50C, 11 parts by wei.ght (dry) of 25~ polyvi~ylocta-decylcarbama~e are added to the toluane. O~ce the product has been homogeni~ed, 35 parts ~y weight (dry) ~aropal 8652 are added; the mixture is aga~n homoge~ized, and 40 part3 b~ weight (dry) E~s~man CP343 and 14 parts by weight (dry) Syloid 276 are slowly added .
The re~ulting suspe~ion has a solid~ content o~.20%
and c~n be stored a~ roo~ temperature.
The mixture is then coated~, while maintaining it 25 at about 400~ using a coating metl~od of the wire bar type, to a thick~ess of 12 g/m~ wet, over the untreated side of a bi-oriented polypropyle~e film having a thickness of 35 ~ d dried for 20 secon~ at 80~C
on an indu9trial-type coating machine.
3~) The other side o~ the substrate i~ then co~ted -, - , , ~iO'774~
-- ~0 --~ith a sol~ent adhesive compri~ing a butylacryla~e-acrylonitrile-acrylic acid copolymer in an he~a~e-toluene sol~ent, the coat i~ dried ~or 50 ~econds at 8DC, and finally, the product is wound into rolls about Z~000 m long. ~he material can be stored wound ~n a roll ~or long periods, and is then conYerted into smaller rolls for consumer's u~e. The tape thus obtained is easily unwound i8 free of surface ~laws, can be applied either manually or with auto~atic s~stems, and retains its properties unaltered with time.
Specifically~ the tape can receive on it~ back any type of mar~ing ~ both in i~k and especiall~ pencil~ ~he marking is stable with time and of the same inten~ity as on usual writing paper. ~he tape i9 particularly transparent on application, and invisible on photocopies and, in particular, on blueprints.
774~
direction, which greatly facilitates its use in practical usual applications.
The chlorinated polyolefine which may be used in the tape of this invention, may be any homopolymer or copolymer polyolefine having a chlorine content in the 15% to 65%
range, or mixtures thereof, and a suitable molecular weight for film formation, a Brookfield viscosity preferably in the to 180 centipoises range and a specific gravity at 25/25C preferably in the 0.850 to 0.950 range, for 25%
solutions in xylene. By way of example, chlorinated polyolefines may be used which are available commercially under the trademark CP 343, produced by Eastman Kodak, U.S.A., or trademark HARDLEN, produced by Toyo Kasey Kogyo, Japan, under the trademark TRAPYLEN, produced by Rowa, Germany. The chlorinated polyolefine varies in amount from 25% to 55%, preferably 35% to 40~ by weight relative to the overall weight (dry) of the anti-adhesive layer componen-ts in the final product.
A usable polyaldehyde resin may be any polyaldehyde resin obtained by reaction of a 4-to-8 carbon atoms, linear or branched chain aliphatic aldehyde such as isobutylaldehyde with urea. Among the ~uitable polyaldehydes is the one available from BASF under the trademark LAROPAL
8652. The u~able amount of polyaldheyde ranges from 20% to 50%, preferably 30% to 40% by dry weight.
In addition to the two film-forming resins used in the anti-adhesive writable layer of the tape of this invention, the layer may include, according to tï
.
.. . .
;
' ~'~"' '~ '' ' :.
~6~77 ~ 6 alternatiYe embodiments of the invention, further re3in componentis.
~us~ ~ccording to ~nother embodiment of the anti-adhesive ~!vritable layer, tl~is comprises 25y to 59~ju of said chlorinated polyole~ine7 15~ to 30p of ~sid polyaldehgde, together with 5~ to 20~ o:E a linear elastomeric polyuretha~e as film~:I'oxmir~
resins~ in addition to said anti-adhesi~e agent ~nd ~aid mattlng ager~t.
~referably, for the film-form~g and bonding resins, the follo~ing proportions are used in this embodimelt: 35,~ to 406jo chaorinated polyole$i~, 20jo to ; 2550 pol~aldehyde, and 10C/~ to 1570 polyurethane.
The usable polyurethane i~ a linear elastomeric ', 15 polyurethane ha~ing preferably a high crystallinity.
I As an example, a polyurethane ob~ained by reacting a i polyester having end hydroxyl group~ as deri~ed from a dicarboxylic acid o~ 4 to 10 carbon atoms and a diol of 4 to 10 carbon~i, with æn aliphatic or 2a aromatic di-isocyanate, ma~ be u~ed. Also a polyester obtained by the reaction of adipic acid with hexanediol and then cross-linked with toluene-di-isocyan~te, may be u~ed.
By way of exemiple9 c.~iable polyurethane i~ the one available from BASF under the trademark of lUsi~E;~
142~.
: ~he anti-3dhe~1~e ~unctio~ ia proYided by lncorporat-ing,q~to the anti-~dhesi~e l~yer ~ the inventive tape, ~n ~: anti-adhe~i~e or rel~aQe agent ~elected from thoRe 3 con~en~ionally utili~ed ~or t~e ~ame pu~po~e. Among ,"., .
lZ60774 such agents may be mentioned the polyvinylalkylcarbamates, e.g. polyvinyloctadecylcarbammate, the alkyilurethane of polyvivylalcohols, and the amides of fatty acids and polyethyleneimine. The anti-adhesive agent is used in amounts ranging from 5~ to 2Q%, preferably 10~ to 15% by weight of the overall weight of the components in the anti-adhe~ive layer.
The anti-adhesive layer is made writable by the incorporation of a matting agent, in accordance with conventional techniques. As the matting agent, an inorganic material may be used in the form of finely divided particles, such as talc, silica, calcium carbonate, etc., a high purity silica being preferredfor instance the high purity ~ilica available under the trademark SYLOYD from W.R.Grace, U.S.A.. The dulling filler should be used in amounts ranging from 5% to 25, preferably 10% to 15~, by weight of the overall dry weight of the anti-adhesive layer components.
The substrate to be used in the tape according to the invention is an olefinic homopolymer or copolymer,such a~
polyethylene, polypropylene, or copolymers thereof. The invention has shown to be specially advantageous with polypropylene substrates. The substrate may be uni-oriented, bi-oriented, or unoriented.
When cutting the final product into small rolls, the tape edges are made easy to cut in the transversal direction,both manually and through automatic or manual dispensers, by creating micro-indentations which facilitate starting of the crosswise cut. The micro-indentations are formed, in , ~ ~6~7~
conformity with con~entional techniques, by mean~ of cutting blades, usually termed l'score cutting".
~ he adhesive layer of the tape of this invention is ~ormed with adhe~i~e products conventionally employed with such tapeR, like an adhesive material includi~g acrylic, polyuretha~e, or polyester copolymers, or natural or synthe~ic rubbers and na~unal or ~ynthetlc resins adhesives.
The tape of this invention is prepared by applying to the polyolefinic substrate the anti adhe~ve layer and adhesive layer, respectively, preferably in the form of a solution or disper~ion in ~ui~able solve~t~7 according to conventional techniques, ~nd then remoYing the solvents by evaporation. ~he a~ti-adhesive layer of this invention may be applied, ~or example, in the ~orm of a solution or dispersion in a hgdro-carbon solvent, such as toluene, by mixing 95q' to 70~ja pre~erably 85/o to 75a/o, ~f said solvent together with 5~/o to 30a/o~ preferably 15a/~ to 25/o~ o~ the mixture o~ the anti-adhesive layer component~ 9 with the u~e of such coating arrang~ents as rotogravure, wire bar (~eyer bar~, roto~ilkscreening, etc~ The thicknesses o~ the substrate ~nd of the adhesive and anti_adhesive writable ~ ayers are uncritical in the inventive tape ,.
25 U~;ually, thiclmes3e~ prefera~ly in the 25 to 40 11m ra~ge ar~ used ~o~ the ~u~ra~e7 in the 0.4 to 10 1~m ra;~ge for the anti-~dhesive la;srer, arld in the .. 18 to 32 ~m range for the adhesive layer.
The re~ulting adhesi~e ~ape ig easil~ ~nwou~d, , - ' . .
~ ~6 ~7 adheres perfectly to di~ferént surfaces~ become~
perf~ctly transparent on application, may be photo-copied, i6 specially suitable for heliograp~ic duplication a~ practiced in the workrooms of engineering draftsmen, i8 unalterab}e with time, and iB writQble by ~11 ordinary writing methods, and in particular, with all types of pencils.
~ he Example which follows iB gi~en by ~ay of ~llu~tra-tion, so as to make the in~ention more clearly understood~
and i~ ~pt to be con~trued as l~mitlng the scopeo~ ~he ~nventlon.
Exam~
The following compone~ts are mixed together in a fast mixer of the blade type7 according to known techniques~ in toluene a3 a sol~ent~ While heating gradu-ally to 50C, 11 parts by wei.ght (dry) of 25~ polyvi~ylocta-decylcarbama~e are added to the toluane. O~ce the product has been homogeni~ed, 35 parts ~y weight (dry) ~aropal 8652 are added; the mixture is aga~n homoge~ized, and 40 part3 b~ weight (dry) E~s~man CP343 and 14 parts by weight (dry) Syloid 276 are slowly added .
The re~ulting suspe~ion has a solid~ content o~.20%
and c~n be stored a~ roo~ temperature.
The mixture is then coated~, while maintaining it 25 at about 400~ using a coating metl~od of the wire bar type, to a thick~ess of 12 g/m~ wet, over the untreated side of a bi-oriented polypropyle~e film having a thickness of 35 ~ d dried for 20 secon~ at 80~C
on an indu9trial-type coating machine.
3~) The other side o~ the substrate i~ then co~ted -, - , , ~iO'774~
-- ~0 --~ith a sol~ent adhesive compri~ing a butylacryla~e-acrylonitrile-acrylic acid copolymer in an he~a~e-toluene sol~ent, the coat i~ dried ~or 50 ~econds at 8DC, and finally, the product is wound into rolls about Z~000 m long. ~he material can be stored wound ~n a roll ~or long periods, and is then conYerted into smaller rolls for consumer's u~e. The tape thus obtained is easily unwound i8 free of surface ~laws, can be applied either manually or with auto~atic s~stems, and retains its properties unaltered with time.
Specifically~ the tape can receive on it~ back any type of mar~ing ~ both in i~k and especiall~ pencil~ ~he marking is stable with time and of the same inten~ity as on usual writing paper. ~he tape i9 particularly transparent on application, and invisible on photocopies and, in particular, on blueprints.
Claims (16)
1. A self-sticking tape, comprising a flexible substrate, a self-sticking coating on one side thereof, and an anti-adhesive writable coating on the opposite side, comprising at least one film forming resin along with at least one anti-adhesive agent and at least one matting agent, wherein said substrate is selected from oriented and non-oriented films of alpha-olefine polymers and copolymers, having at least the side bearing said anti-adhesive coating free from any additional priming layer and adhesion promoting surface treatment, and said anti-adhesive writable coating comprises 255 to 55% by weight of at least one chlorinated polyolefine and 20% to 50% by weight of a polyaldehyde resin as said film-forming resin and as substrate adhesive promoter resin.
2. A self-sticking tape, according to claim 1, wherein said anti-adhesive writable coating comprises 5% to 20% by weight of said at least one anti-adhesive agent and 5% to 25% by weight of said at least one matting agent.
3. A tape according to claim 1, wherein said substrate is a polypropylene substrate.
4. A self-sticking tape, according to claim 1, wherein said anti-adhesive writable coating comprises 35% to 40% by weight of said chlorinated polyolefine, 30% to 40% of said polyaldehyde, 10% to 15% of said anti-adhesive agent, and 10% to 15% of said matting agent.
5. A tape according to claim 1, wherein said chlorinated polyolefine is a homopolymer or copolymer film-forming polyolefine having a chlorine content of 155 to 65%.
6. A tape according to claim 1, wherein said polyaldehyde resin is a film-forming resin obtained by the condensation of a linear or branched chain aliphatic aldehyde with 4 to 8 carbon atoms in the aliphatic chain with urea.
7. A tape according to claim 1, wherein said anti-adhesive agent is selected from polyvinylalkylcarbamates, alkylurethanes of polyvinylalcohols, and amides of fatty acids and polyethyleneimine.
8. A tape according to claim 1, wherein said matting agent comprises silica.
9. A tape according to claim 1, wherein said anti-adhesive writable coating further comprises a linear elastomeric polyurethane.
10. A tape according to claim 9, wherein said anti-adhesive writable coating comprises 25% to 50% by weight of said chlorinated polyolefine, 15% to 30% by weight of said polyaldehyde resin, and 5% to 20% by weight of said linear elastomeric polyurethane as the film-forming and substrate adhesive promoters resin.
11. A tape according to claim 1o, wherein said anti-adhesive writable coating comprises 35% to 40% by weight of said chlorinated polyolefine, 20% to 25% by weight of said polyaldehyde, 10% to 15% by weight of said linear elastomeric polyurethane, 10% to 15% by weight of said anti-adhesive agent, and 10% to 15% by weight of said matting agent.
12. A tape according to any of claims 9 to 11, wherein said linear elastomeric polyurethane is the reaction product of a hydroxy-terminated polyester of a dicarboxylic acid of 4 to 10 carbon atoms and a diol of 4 to 10 carbon atoms with an aliphatic or aromatic di-isocyanate.
13. A tape according to claim 10, wherein said linear elastomeric polyurethane is the reaction product of a hydroxy-terminated polyester of a dicarboxylic acid having 4 to 10 carbon atoms and a diol having 4 to 10 carbon atoms with an aliphatic or aromatic di-isocyanate.
14. A tape according to claim 9, wherein said substrate is a polypropylene substrate.
15. A tape according to either claim 9 or 10, wherein said chlorinated polyolefine is a homopolymer or copolymer film-forming polyolefine having a chlorine content of 15% to 65%.
16. A tape according to claim 10, wherein said polyaldehyde resin is a film-forming resin obtained by condensation of a linear or branched chain aliphatic aldehyde of 4 to 8 carbon atoms with urea.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT20815/84A IT1173584B (en) | 1984-05-04 | 1984-05-04 | SELF-ADHESIVE TAPE OF WRITABLE TYPE |
| IT20815A/84 | 1984-05-04 | ||
| EP841089048 | 1984-07-27 | ||
| EP84108904A EP0163761B1 (en) | 1984-05-04 | 1984-07-27 | Writable adhesive tape |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1260774A true CA1260774A (en) | 1989-09-26 |
Family
ID=26092036
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000480700A Expired CA1260774A (en) | 1984-05-04 | 1985-05-03 | Writable adhesive tape |
Country Status (2)
| Country | Link |
|---|---|
| AT (1) | ATE60075T1 (en) |
| CA (1) | CA1260774A (en) |
-
1984
- 1984-07-27 AT AT84108904T patent/ATE60075T1/en active
-
1985
- 1985-05-03 CA CA000480700A patent/CA1260774A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| ATE60075T1 (en) | 1991-02-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4708907A (en) | Writable adhesive tape | |
| US4960637A (en) | Polymeric films | |
| US6403190B1 (en) | Release liners for pressure sensitive adhesive labels | |
| US4536441A (en) | Adhesive tape | |
| US5401560A (en) | Polymer backed material with non-slip surface using E-beam cured urethane binder | |
| US5093187A (en) | Tear strip | |
| CA2251196A1 (en) | Polyethylene wax as processing aid for hotmelt adhesive compositions | |
| US5674600A (en) | Laminating film without a release layer, process for the production thereof and use thereof | |
| US4070523A (en) | Printable pressure-sensitive adhesive tapes | |
| US4424244A (en) | Printable release coating composition tapes | |
| US5374482A (en) | Masking tape | |
| JP2003335911A (en) | Film and adhesive tape made of the same | |
| CA1158489A (en) | Coated film | |
| EP0852611B1 (en) | Clear monolayer label filmstock | |
| AU686711B2 (en) | Self-adhesive wallcoverings | |
| CA1260774A (en) | Writable adhesive tape | |
| US6139967A (en) | Clinging sheet | |
| US5876852A (en) | Laminating film without a release layer, process for the production thereof and use thereof | |
| US4751141A (en) | Process for the manufacture and use of a polypropylene foil with improved adhesion | |
| EP0158428B1 (en) | Coating composition and directly printable pressure-sensitive adhesive tape comprising same | |
| JP4741058B2 (en) | Water- and moisture-proof paper resin composition, water- and moisture-proof paper using the same, and method for producing the same | |
| EP0312289A1 (en) | Polymeric films | |
| JP4441010B2 (en) | Hot melt composition, moisture-proof paper using the same, and method for producing the same | |
| EP2094482B1 (en) | Labels | |
| JP3840745B2 (en) | Easy adhesive film for vinyl chloride resin |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |