RS59284B2

RS59284B2 - Tanning process for producing leather with high elastic properties and leather obtained

Info

Publication number: RS59284B2
Application number: RS20191146A
Authority: RS
Inventors: Daniele Marinai
Original assignee: Kemas S R L
Priority date: 2013-09-04
Filing date: 2014-08-29
Publication date: 2025-10-31
Also published as: RS59284B1; ES2743414T3; SI3041962T2; SI3041962T1; HRP20191429T4; ITPI20130078A1; ES2743414T5; FI3041962T4; PL3041962T3; PT3041962T; EP3041962B1; PL3041962T5; EP3041962A1; HRP20191429T1; WO2015033259A1; EP3041962B2

Description

Opis Description

Oblast tehnike Technical field

[0001] Predmetni pronalazak se odnosi na hemijski postupak uključen u postupak štavljenja i pogodan za dobijanje kože koja ima posebne estetske i funkcionalne osobine. [0001] The present invention relates to a chemical process included in the tanning process and suitable for obtaining leather that has special aesthetic and functional properties.

[0002] Pronalazak se takođe odnosi na kožu koja ima osebujne estetske i funkcionalne kvalitete dobijene određenim postupcima štavljenja. [0002] The invention also relates to leather having distinctive aesthetic and functional qualities obtained by certain tanning procedures.

Stanje tehnike State of the art

[0003] Postupak štavljenja je dug i složen i u osnovi je hemijski proces koji se sastoji od uzastopnih faza koje se naizmenično mešaju mehaničkim operacijama, a u kojima su životinjske kože pripremljene za izradu krznarskih proizvoda napravljene ne samo otporno na truljenje, već i komercijalno privlačne dajući im određene karakteristike boje, mekoće, teksture , miris, izdržljivost, otpornost i ostale karakteristike. [0003] The tanning process is long and complex and is basically a chemical process that consists of successive phases that are alternately mixed with mechanical operations, and in which the animal skins prepared for the production of fur products are made not only resistant to rotting, but also commercially attractive by giving them certain characteristics of color, softness, texture, smell, durability, resistance and other characteristics.

[0004] Kože koje se koriste u postupku štavljenja mogu da potiču od bilo koje kopnene, morske, vodozemne ili prenate životinje, čija je upotreba naravno dozvoljena ili regulisana zakonom. [0004] The skins used in the tanning process can come from any terrestrial, marine, aquatic or predated animal, the use of which is of course permitted or regulated by law.

[0005] Celi postupak se može podeliti u tri opšte faze: štavljenje, obrada nakon štavljenja/ponovno štavljenje (doštava) i završna obrada. Svakoj od ovih makrofaza pripada veći broj pojedinačnih faza sa specifičnim namenama. [0005] The whole process can be divided into three general stages: tanning, processing after tanning/re-tanning (delivery) and finishing. Each of these macrophases has a larger number of individual phases with specific purposes.

[0006] Štavljenje se sastoji od svih pripremnih operacija za štavljenje, poznatih i kao pripremne operacije prerade kože, i samog štavljenja. Pripremne operacije uključuju: kvašenje (močenje) sirove kože, uklanjanje mesa, skidanje dlake, luženje, cepanje, odluživanje/otkrečavanje, nagrizanje (bajcovanje), odmašćivanje. [0006] Tanning consists of all preparatory operations for tanning, also known as preparatory operations for leather processing, and tanning itself. Preparatory operations include: wetting (soaking) of rawhide, fleshing, hair removal, leaching, splitting, descaling/deliming, pickling (staining), degreasing.

[0007] Cilj kvašenja je da obnovi hidrataciju krzna i kože koja je izgubila u procesu konzerviranja, ukloni prljavštinu, krv, gnojivo i so u slučaju soljenih koža ili krzna. Izvodi se u bubnjevima uz upotrebu vode, pomoćnih materija i surfaktanata [0007] The aim of wetting is to restore the hydration of fur and skin that has been lost in the preservation process, to remove dirt, blood, fertilizer and salt in the case of salted hides or furs. It is carried out in drums with the use of water, auxiliary substances and surfactants

[0008] Proces skidanja dlaka se koristi za uklanjanje dlaka i epiderme, a tada se uvek izvodi izuzev ako pravi koža sa dlakom ili krznom. Luženje je neophodno da bi se omekšala vlaknasto tkanje kože. Pošto se uklanjanje i luženje vrši sa istim hemikalijama, dve faze se izvode istovremeno i obično se nazivaju fazom uklanjanja dlaka-luženje ili, jednostavnije, fazom oluženja. Uklanjanje dlaka i luženje se uobičajeno odvija u vlažnom okruženju, najbolje u bubnju sa odgovarajućom količinom vode i sa dodatkom redukujućih agenasa, posebno natrijum-sulfida (Na2S), natrijum-hidrogen sulfata (NAHS) i kreča (Ca(OH)2, kalcijum hidroksid). [0008] The hair removal process is used to remove hair and epidermis, and then it is always performed unless it is making leather with hair or fur. Leaching is necessary to soften the fibrous tissue of the skin. Since depilation and leaching are done with the same chemicals, the two phases are performed simultaneously and are commonly referred to as the depilation-leaching phase or, more simply, the leaching phase. Hair removal and leaching usually takes place in a wet environment, preferably in a drum with an adequate amount of water and the addition of reducing agents, especially sodium sulphide (Na2S), sodium hydrogen sulphate (NAHS) and lime (Ca(OH)2, calcium hydroxide).

[0009] Odluživanje, namakanje i odmašćivanje su druge važne hemijske operacije. Odluživanjem većeg dela lužine koje se koristi u procesu uklanjanja dlačica, je uklanjeno se sa kože. Kao sredstva za odluživanje mogu se koristiti jake kiseline (sumporna, hlorovodonična), slabe kiseline (mravlja, sirćetna, borna kiselina, itd.), ili soli u disocijaciji kiseline, kao što je amonijum sulfat ili hlorid. Nagrizanje završava delovanje faze luženja što izaziva dalje opuštanje strukture kolagena. U tom cilju koriste se proteolitički enzimi. Odmašćivanje se koristi da se eliminiše ili barem smanji originalni sadržaj masti na koži koji može dovesti do problema u apsorpciji i fiksiranju hemikalija i do različitih vrsta oštećenja na gotovoj koži. Izvodi se primenom jonskih ili nejonskih površinski aktivnih sredstava. Odluživanje, namakanje i odmašćivanje odvijaju se u vlažnom okruženju, najbolje u bubnju u prisustvu, pored navedenih supstanci, odgovarajuće količine vode. [0009] Descaling, soaking and degreasing are other important chemical operations. By leaching most of the lye used in the hair removal process is removed from the skin. Strong acids (sulfuric, hydrochloric), weak acids (formic, acetic, boric acid, etc.), or salts in acid dissociation, such as ammonium sulfate or chloride, can be used as descaling agents. Etching completes the action of the leaching phase which causes further relaxation of the collagen structure. For this purpose, proteolytic enzymes are used. Degreasing is used to eliminate or at least reduce the original fat content of the skin which can lead to problems in the absorption and fixation of chemicals and to various types of damage to the finished skin. It is performed using ionic or non-ionic surfactants. Descaling, soaking and degreasing take place in a humid environment, preferably in a drum in the presence, in addition to the above substances, of an appropriate amount of water.

[0010] Skidanje mesine je mehanička operacija kojom se eliminišu ostaci mesa i masnog tkiva u potkožnom sloju. [0010] Meat removal is a mechanical operation that eliminates the remains of meat and fatty tissue in the subcutaneous layer.

[0011] Međutim, nakon pripremnih operacija, koža je još uvek podložna truljenju i mora se podvrgnuti štavljenju, obično posle zakiseljavanja (piklovanja). Najčešći i najpopularniji tipovi procesa štavljenja su hromno štavljenje i biljno štavljenje, dok druge vrste štavljenja mogu koristiti druge reagense kao što su sintetički tanini, fosfonijum, aluminijum ili cirkonijum soli, aldehidi, ulja ili njihove smeše. Hromno štavljena koža se naziva Wet Blue jer na kraju operacije imaju tipično plavkastu / plavu boju. Štavljenje se vrši u vlažnoj sredini. [0011] However, after preparatory operations, the skin is still susceptible to rotting and must undergo tanning, usually after acidification (pickling). The most common and popular types of tanning processes are chrome tanning and vegetable tanning, while other types of tanning may use other reagents such as synthetic tannins, phosphonium, aluminum or zirconium salts, aldehydes, oils or mixtures thereof. Chrome tanned leather is called Wet Blue because at the end of the operation they have a typical bluish / blue color. Tanning is done in a humid environment.

[0012] Štavljena koža je i dalje samo kruti poluproizvod, sličan kartonu i sa bojom karakterističnom za tip štavljenja kojim je dobijen. Da bi postao gotov proizvod koji se može prodati, mora se podvrgnuti operacijama posle štavljenja (nadoštave) i završne obrade. [0012] Tanned leather is still only a rigid semi-product, similar to cardboard and with a color characteristic of the type of tanning by which it was obtained. In order to become a salable finished product, it must undergo post-tanning and finishing operations.

[0013] Operacije nadoštave uključuju: brušenje, presovanje, skidanje dlake, cepanje, ponovno štavljenje, bojenje, mašćenje, sušenje i drugo. [0013] Finishing operations include: sanding, pressing, hair removal, splitting, re-tanning, dyeing, oiling, drying and others.

[0014] Brušenje, presovanje, uklanjanje dlake, cepanje i sušenje su mehaničke operacije. [0014] Grinding, pressing, hair removal, splitting and drying are mechanical operations.

[0015] Ponovno štavljenje, bojenje i močenje su osnovni hemijski procesi za određivanje karakteristika proizvoda koje se žele postići u proizvodnji kože. Posebno, štavljenje je obrada po izboru sa pomoćnim sredstvima i sredstvima za štavljenje, često drugačijim od onih koji se koriste za glavno štavljenje, koje služi za promenu karakteristika kože postignuto gladvnim štavljenjem. Na primer, ako želite da napravite kožu manje fleksibilnu od kože dobijene hromnim štavljenjem, ponovno štavljenje treba izvesti biljnim taninima. Suprotno tome, ako želite da napravite fleksibilniju i meku kožu od kože biljnim štavljenem, mora da se izvrši hromna doštava. Dalje, često se sredstva za štavljenje na bazi aluminijuma, cirkonijuma ili titanijuma koriste kao sredstva za doštavu da bi se dobila koža reaktivnija prema bojama i samim tim da bi se dobile intenzivnije i sjajnije boje. [0015] Re-tanning, dyeing and soaking are the basic chemical processes for determining the product characteristics to be achieved in leather production. In particular, tanning is a treatment of choice with auxiliaries and tanning agents, often different from those used for the main tanning, which serves to change the characteristics of the leather achieved by starved tanning. For example, if you want to make leather less flexible than chrome-tanned leather, retanning should be done with vegetable tannins. Conversely, if you want to make a more flexible and soft leather than vegetable tanned leather, chrome delivery must be done. Furthermore, aluminum, zirconium or titanium based tanning agents are often used as delivery agents to make the skin more reactive to the dyes and therefore to produce more intense and brighter colors.

[0016] Bojenje je operacija koja koži daje željenu boju. Bojenje se obično vrši u rotirajućoj bačvi, na unapred definisanoj temperaturi, obično sa bojama, kiselim bojama, ali i organometalnim, kationskim, reaktivnim, sumpornim, itd. sredstvima za bojenje. [0016] Dyeing is an operation that gives the skin the desired color. Dyeing is usually done in a rotating barrel, at a predefined temperature, usually with dyes, acid dyes, but also organometallic, cationic, reactive, sulfur, etc. coloring agents.

[0017] Mašćenje je hemijska operacija koja se koristi za unošenje lubrikansa između vlakana kože, koji razdvaja vlakna i omogućava im da se klize jedno preko drugog Na ovaj način koža može pretpostaviti fleksibilnost, mekoću i druge kvalitete koje se komercijalno cene. Za mašćenje se koriste ulja ili masti životinjskog, biljnog, mineralnog ili sintetičkog porekla. Naravno, ulja ili masti kao takva, da bi se koristila kao lubrikansi za kožu, hemijski su modifikovana ili dodata sa emulgatorima da bi ih učinila rastvornim u vodi, a naročito da bi im obezbedila određeni kapacitet vezivanja za kožu. Obično da bi lubrikanasi postali rastvorni, uvode se anjonske hidrofilne grupe (sulfonatne, sulfatne, fosfatne, fosfonatne itd.), katjonske (kvartarni amonijum itd.) ili neionske. U čestom slučaju mašćenja anjonskim proizvodima, hemija mašćenja je prilično slična onoj za boju za koju se, ponekad, bojenje i mašćenje vrše istovremeno. [0017] Oiling is a chemical operation used to introduce a lubricant between the fibers of the leather, which separates the fibers and allows them to slide over each other. In this way, the leather can assume flexibility, softness and other qualities that are commercially valued. Oils or fats of animal, vegetable, mineral or synthetic origin are used for greasing. Of course, oils or fats as such, in order to be used as skin lubricants, are chemically modified or added with emulsifiers to make them soluble in water, and especially to provide them with a certain binding capacity to the skin. Usually, to make lubricants soluble, anionic hydrophilic groups (sulfonate, sulfate, phosphate, phosphonate, etc.), cationic (quaternary ammonium, etc.) or nonionic groups are introduced. In the frequent case of degreasing with anionic products, the chemistry of degreasing is quite similar to that of paint, for which dyeing and degreasing are sometimes done simultaneously.

[0018] Kada se završe obrade nakon štavljenja, a posebno sušenje, koža je spremna da se podvrgne delikatnim i složenim operacijama, kako mehaničkim, tako i hemijskim, završnim obradama, korisnim da prikaže željene estetske i funkcionalne karakteristike. [0018] When the post-tanning treatments, especially drying, are completed, the leather is ready to undergo delicate and complex operations, both mechanical and chemical, finishing treatments, useful to show the desired aesthetic and functional characteristics.

[0019] Hemijska završna obrada sastoji se u prekrivanju površine kože tankim filmom sintetičkog materijala (akrilne smole, butadiena, poliuretana) ili prirodnim materijalom (kazeinom, albuminom, modifikovanim proteinom baziranim celulozi koji formira film ), a koji može da sadrži pigmente, boje, omekšivače, agense za poliranje i različita pomoćna sredstava. Film se može načiniti na površini kože polazeći od monomera ili polimera različite prirode ili se može oblikovati i naneti na površinu kože uz pomoć lepka. U prvom slučaju smeša veziva za formiranje filma i pomoćnih sredstava se nanosi na površinu kože prskanjem, valjcima (nanošenje valjkom), sa zavesom za lakiranje (proizvodnja "lakirane kože"). U drugom slučaju film je najčešće na poliuretanskoj osnovi, modernog dizajna, promenljive debljine, na različitim podlogama sa kojih se prenosi na kožu. Iz tog razloga se ova vrsta završne obrade često generički naziva „završna obrada“. [0019] Chemical finishing consists in covering the surface of the skin with a thin film of synthetic material (acrylic resin, butadiene, polyurethane) or natural material (casein, albumin, modified protein-based cellulose that forms the film), which may contain pigments, dyes, softeners, polishing agents and various auxiliaries. The film can be made on the surface of the skin starting from monomers or polymers of different nature or it can be shaped and applied to the surface of the skin with the help of glue. In the first case, a mixture of film-forming binders and auxiliaries is applied to the surface of the leather by spraying, rolling (roller application), with a coating curtain (production of "lacquered leather"). In the second case, the film is usually polyurethane-based, modern design, variable thickness, on different substrates from which it is transferred to the skin. For this reason, this type of finishing is often referred to generically as "finishing".

[0020] U stvarnoj praksi, potraga za inovativnim proizvodima ili drugim proizvodnim često dovodi do obrnutog ili modifikovanog redosleda operacija, pri čemu se prvo izvršava završna obrada, a zatim se koža ponovo vlaži, štavi, boji i omašćuje, kombinovanjem i razmenom svih normalnih faza procesa štavljenja [0020] In actual practice, the search for innovative products or other manufacturing often leads to a reversed or modified sequence of operations, where the finishing is first carried out, and then the leather is re-wetted, tanned, dyed and oiled, combining and exchanging all the normal stages of the tanning process.

[0021] Međutim, suštinska razlika između hemijskih operacija završne obrade i hemijskih operacija faza štavljenja i naknadnog štavljenja sastoji se u činjenici da se poslednje izvode sa visokom apsolutnom vlažmošću kože, a prve se izvode uglavnom na suvo, tj. sa apsolutnom vlažnošću kože, koja se odnosi na njihovu težinu suve materije, manjom od 25% (prosečne završne operacije se izvode sa apsolutnom vlažnošću kože manjom od 15%, dok se operacije štavljenja i doštave izvode sa apsolutnom vlažnošću kože od obično većom od 50%, pa čak i do 2000% i više). [0021] However, the essential difference between the chemical operations of the final treatment and the chemical operations of the tanning and post-tanning phases consists in the fact that the latter are carried out with high absolute moisture of the skin, and the former are carried out mostly dry, i.e. with an absolute moisture content of the hides, referring to their weight of dry matter, of less than 25% (average finishing operations are carried out with an absolute moisture content of the hides of less than 15%, while tanning and rendering operations are carried out with an absolute moisture content of the hides of usually greater than 50%, and even up to 2000% and more).

[0022] Od ranije je poznata upotreba elastomera u postupcima završne obrade. Na primer u US patentu 4,581,034 opisan je postupak završne obrade prema kome se na površinu kože nanosi sintetički karboksilatni elastomer dobijen emulzijom kroz polimerizaciju nezasićenih karboksilnih kiselina, butadiena ili izoprena, stirena i akrilonitrila. Oblaganje sa supstancama na bazi elastomera daje koži osobine nepropusnost, elastičnost, mehaničku otpornost, međutim, ove karakteristike zavise od celovitosti i homogenosti sloja za oblaganje. [0022] The use of elastomers in finishing processes has been known for a long time. For example, US patent 4,581,034 describes a finishing process according to which a synthetic carboxylate elastomer is applied to the skin surface obtained by emulsion through the polymerization of unsaturated carboxylic acids, butadiene or isoprene, styrene and acrylonitrile. Coating with elastomer-based substances gives the skin the properties of impermeability, elasticity, and mechanical resistance, however, these characteristics depend on the integrity and homogeneity of the coating layer.

[0023] Takođe su poznate obrade koje su deo procesa štavljenja u kome se elastomeri dodaju u komoru za tretiranje u vlažnoj fazi postupka, poželjno tokom faza naknadnog štavljenja ili štavljenja. U nastavku će se takav postupak nazvati "gumiranje" i deo je procesa štavljenja, a "gumirana koža" će biti koža dobijena postupkom štavljenja koji sadrži postupak gumeniranja. Na primer, američki patent 2,949,335 opisuje tretman gumiranja, koji se izvodi u prisustvu najmanje jednog agensa za štavljenje, koji obezbeđuje dodavanje u komporu za tretiranje vodene emulzije polimera ili kopoimera ili smeše polimera ili elastomernih kopolimera. U dokumentu se navodi mogućnost upotrebe smeša polimera i kopoimera najrazličitijih tipova za dobijanje štavljenih koža koja imaju posebne osobine koje između ostalog imaju funkciju dodatih elastomera. Konkretno, pominje se upotreba emulzije koja sadrži kopolimer dobijen iz butadiena, akrilonitrila i stirena za dobijanje kože sa sledećim karakteristikama visoke nepromočivosti, visoke otpornosti na abraziju i visoke otpornosti na kidanje. [0023] Also known are treatments that are part of the tanning process in which elastomers are added to the treatment chamber in the wet phase of the process, preferably during the post-tanning or tanning phases. In the following, such a process will be called "gumming" and is part of the tanning process, and "gummed leather" will be leather obtained by a tanning process that includes a gumming process. For example, U.S. Patent 2,949,335 describes a rubberization treatment, performed in the presence of at least one tanning agent, which provides addition to the treatment compound of an aqueous emulsion of a polymer or copolymer or a mixture of polymers or elastomeric copolymers. The document mentions the possibility of using mixtures of polymers and copolymers of various types to obtain tanned leathers that have special properties that, among other things, have the function of added elastomers. In particular, it mentions the use of an emulsion containing a copolymer derived from butadiene, acrylonitrile and styrene to obtain leather with the following characteristics of high waterproofness, high abrasion resistance and high tear resistance.

[0024] Iako postupak definisan u citiranom patentu US 2,949,335 zapravo može doneti poboljšanja u pomenutim karakteristikama kože dobivene na taj način, potrebno je potražiti rešenja koja mogu omogućiti praktičnu primenu onoga što je slično sugerisano i koja mogu da optimiziraju neke specifične karakteristike procesa gumiranja i povezane gumirane kože. [0024] Although the process defined in the cited patent US 2,949,335 can actually bring improvements in the mentioned characteristics of the leather obtained in this way, it is necessary to look for solutions that can enable the practical application of what is similarly suggested and that can optimize some specific characteristics of the rubberizing process and the associated rubberized leather.

[0025] Dalje, umetanje tretmana gumiranja u postupku štavljenja određuje potrebu traženja posebnog načina izvođenja narednih procesa sušenja kako bi se dobio najbolji konačni rezultat i time izbegli problemi svojstveni karakteristikama elastičnosti stečenih uglavnom kod kože tretirane dodavanjem elastomera tokom vlažne faze štavljenja. [0025] Furthermore, the insertion of rubberizing treatment in the tanning process determines the need to search for a special way of performing subsequent drying processes in order to obtain the best final result and thus avoid problems inherent in the characteristics of elasticity acquired mainly in leather treated by adding elastomer during the wet phase of tanning.

[0026] Uobičajeno, najčešće korišten postupak sušenja je vakuum sušenje koje u svom širem značenju obuhvata i korake provlačenja kože kroz valjke sa povratnim kretanjem za preradu kože, presovanja (ako je potrebno) i sušenja. Koža koja dolazi iz faza procesa štavljenja koja se odvijaju u vlažnom okruženju i zato u proseku sadrži količinu vode koja iznosi približno 400% njene suve težine, suši se vešanjem ili njenim polaganjem pomoću hvataljki ili u drugi način, nakon čega se prebacuje u mašinu u kojoj je valjci opuštaju i uklanjaju oko 70% - 80% vlage koja se nalazi u koži. Naknadno sušenje vakuumom vrši se umetanjem kože između dve ploče zagrejane na temperaturu između 30 ° i 65 °. Nakon odlaganja kože sa zrnatastom stranom okrenutom na donju ploču, gornja ploča se spušta i uređaj za usisavanje stvara određeni stepen vakuuma između dve ploče. Pravilnim sušenjem dobija se koža sa zaostalom vlagom ispod 20% suve mase, podešavanjem temperature, stepena vakuuma i vremena sušenja [0026] Usually, the most commonly used drying procedure is vacuum drying, which in its broader meaning includes the steps of passing the leather through rollers with a reciprocating movement for processing the leather, pressing (if necessary) and drying. Leather that comes from the stages of the tanning process that take place in a humid environment and therefore contains an amount of water that is approximately 400% of its dry weight on average, is dried by hanging or laying it down using tongs or in another way, after which it is transferred to a machine where the rollers relax it and remove about 70% - 80% of the moisture contained in the leather. Subsequent vacuum drying is done by inserting the skin between two plates heated to a temperature between 30 ° and 65 °. After placing the hide with the grain side facing the bottom plate, the top plate is lowered and a suction device creates a certain degree of vacuum between the two plates. Proper drying results in leather with a residual moisture below 20% of the dry weight, by adjusting the temperature, vacuum level and drying time.

[0027] Kada se sušenje mora da izvede na gumiranoj koži, potrebno je na poseban način sprečiti naboravanje koje bi bilo posebno teško ukloniti provlačenjem kože kroz valjke sa povratnim kretanjem za preradu kože, i sušenjem ili čak upotrebom drugih sredstava posebno konstruisanih u tu svrhu. Uobičajeno, oštećenja poput bora ili nabora ili prekomerno skupljanje kože izbegavaju se održavanjem kože rastegnutom, između izlaza iz poslednje vlažne faze i provlačenjea kože kroz valjke sa povratnim kretanjem za preradu kože ili sušenja vakuumom, korišćenjem mehaničkog oruđa, posebno štipaljki, deluje blizu graničnog područja kože. Ovo mehaničko dejstvo uzrokuje, međutim, znatan nedostatak homogenosti fizičkih i mehaničkih karakteristika kože između delova uhvaćenih štipaljkama i delova koji su najudaljeniji od njih, odnosno centralnih delova kože. [0027] When drying must be performed on rubberized leather, it is necessary to prevent wrinkling in a special way, which would be particularly difficult to remove by pulling the leather through rollers with a reciprocating movement for leather processing, and drying or even using other means specially designed for that purpose. Normally, damage such as wrinkling or folds or excessive skin shrinkage is avoided by keeping the skin stretched, between exiting the last wet phase and passing the skin through reciprocating rollers for leather processing or vacuum drying, using mechanical tools, especially tweezers, acting close to the border area of the skin. This mechanical effect causes, however, a considerable lack of homogeneity of the physical and mechanical characteristics of the skin between the parts captured by the clips and the parts furthest from them, i.e. the central parts of the skin.

[0028] Uobičajeno, nakon sušenja izvode se završni koraci koji uključuju presovanje. Presovanje, koje se uobičajeno vrši pomoću valjaka za presovanje, opremljenih bušačima, zahteva temperature veće od temperature sušenja, obično između 90 ° i 130° C i pritiske obično između 250 i 300 Bara. Druga važna varijabla procesa presovanja je trajanje pritiska koji je u proseku između 5 i 20 sekundi. Poznato je da se presovanje može izvršiti istovremeno sa vakuum sušenjem, korišćenjem vakuumskih mašina za sušenje koje su opremljene trodimenzionalnim pločama koje su opremljene uzorkom za utiskivanje u kožu. Ova vrsta vakuumskog sušenja presovanjem je veoma povoljna jer omogućava uštedu vremena i troškova za mašine, međutim ne daje optimalne rezultate kada se koristi na ne gumiranoj koži ili na konvencionalnoj gumiranoj koži. [0028] Usually, after drying, final steps involving pressing are carried out. Pressing, which is usually carried out using press rollers equipped with punches, requires temperatures higher than the drying temperature, usually between 90° and 130° C and pressures usually between 250 and 300 Bar. Another important variable of the pressing process is the duration of the pressing, which is on average between 5 and 20 seconds. It is known that pressing can be done simultaneously with vacuum drying, using vacuum drying machines that are equipped with three-dimensional plates that are equipped with a pattern for pressing into the leather. This type of vacuum press drying is very advantageous because it saves time and costs for the machines, however it does not give optimal results when used on non-rubberized leather or on conventional rubberized leather.

Kratak opis pronalaska Brief description of the invention

[0029] Cilj predmetnog pronalaska je predložiti postupak štavljenja koji uključuje tretman "gumiranja", tj. obrada tokom koje se dodaju supstance koje sadrže elastomerne polimere tokom vlažne faze postupka štavljenja, što omogućava proizvodnju kože sa karakterističnim estetskim i funkcionalnim karakteristikama. [0029] The aim of the present invention is to propose a tanning procedure that includes a "rubbing" treatment, ie. processing during which substances containing elastomeric polymers are added during the wet phase of the tanning process, which enables the production of leather with characteristic aesthetic and functional characteristics.

[0030] Sledeći cilj predmetnog pronalaska je da predloži postupak štavljenja koji uključuje postupak "gumiranja" koji omogućava izradu kože koja ima posebne i optimizovane karakteristike pritiska pomoću različitih sistema za presovanje koji se koriste u oblasti tehnike i/ili otpornosti na cepanje klinom i/ili otpornost zrnatosti kože na delaminaciju (break grain resistance). [0030] The next objective of the present invention is to propose a tanning process that includes a "rubbering" process that enables the production of leather that has special and optimized pressure characteristics by means of various pressing systems used in the field of technique and/or resistance to wedge splitting and/or resistance of the grain of the leather to delamination (break grain resistance).

[0031] Naredni cilj predmetnog pronalaska je da predloži postupak štavljenja koji sadrži postupak "gumiranja" koji omogućava da se dobije gumirana koža sa hemijsko-fizičkim karakteristikama suštinski konstantnim duž cele debljine kože. [0031] Another goal of the present invention is to propose a tanning process that includes a "rubbering" process that allows to obtain rubberized leather with chemical-physical characteristics essentially constant along the entire thickness of the leather.

[0032] Sledeći cilj predmetnog pronalaska je da predloži postupak štavljenja koji uključuje postupak „gumiranja“ koji omogućava izbegavanje problema koji su tipično povezani sa sušenjem gumirane kože. [0032] A further aim of the present invention is to propose a tanning process that includes a "gumming" process that allows avoiding the problems typically associated with drying gummed leather.

[0033] Sledeći cilj predmetnog pronalaska je da obezbedi postupak štavljenja koji obuhvata postupak "gumiranja" koji omogućava optimizaciju procesa presovanja i sušenja dobijene kože. [0033] The next objective of the present invention is to provide a tanning process that includes a "gumming" process that enables optimization of the process of pressing and drying the obtained leather.

[0034] Sledeći cilj ovog pronalaska je da predloži gumiranu kožu koja ima bolje karakteristike, u poređenju sa konvencionalnom gumiranom kožom, sa stanovišta otpornosti na kidanje, otpornost zrnatosti kože na delaminaciju, homogenosti fizičkih i mehaničkih karakteristika duž cele debljine kože, mogućmosti štampanja, oblikovanju. [0034] The next objective of this invention is to propose rubberized leather that has better characteristics, compared to conventional rubberized leather, from the point of view of resistance to tearing, resistance of the grain of the leather to delamination, homogeneity of physical and mechanical characteristics along the entire thickness of the leather, possibility of printing, shaping.

[0035] Prema aspektu ovog pronalaska, gornji predmeti i drugi se postignuti su pomoću postupka prema onome što je izloženo i naznačeno u nezavisnom patentnom zahtevu 1. [0035] According to an aspect of the present invention, the above objects and others are achieved by the process as set forth and indicated in independent patent claim 1.

[0036] Zahtevi zavisni od patentnog zahteva 1 opisuju druge karakteristike ovog pronalaska ili varijante glavne inventivne ideje. [0036] The dependent claims of patent claim 1 describe other features of the present invention or variants of the main inventive idea.

[0037] Tipično, proces štavljenja obuhvata veći broj hemijskih operacija u vlažnoj fazi, pri čemu je apsolutna vlažnost kože u odnosu na njenu suvu težinu veća od 25%. Uobičajeni postupak gumiranja omogućava, tokom najmanje vlažne faze postupka štavljenja, dovođenje određene količine elastomera u okruženje za obradu. [0037] Typically, the tanning process includes a large number of chemical operations in the wet phase, where the absolute humidity of the leather in relation to its dry weight is greater than 25%. The usual gumming process allows, during the least wet phase of the tanning process, to introduce a certain amount of elastomer into the processing environment.

[0038] Prema predmetnom pronalasku, navedeni elastomeri se sastoje od polimera ili smeše polimera koji pripadaju porodici karboksiliratnih termoplastičnih elastomera, u količini suve mase proizvoda koji sadrži elastomere od najmanje 0,1% težine svežih soljenih koža ili 0,5% težine vlažnih obrijanih koža ili 1% suve težine pomenutih koža. [0038] According to the present invention, said elastomers consist of polymers or mixtures of polymers belonging to the family of carboxylated thermoplastic elastomers, in the amount of dry mass of the product containing elastomers of at least 0.1% of the weight of fresh salted skins or 0.5% of the weight of wet shaved skins or 1% of the dry weight of said skins.

[0039] Tretman gumiranja koji se vrši dodavanjem polimera u komoru za tretiranje kako je gore definisano, stvara karboamidne veze između kože i samog polimera koje su vrlo jake stabilne i planarne kovalentne veze, u osnovi koje se ne mogu dobiti dodatkom elastomera različitog tipa, koje su uglavnom odgovorne za visok kvalitet otpornosti na kidanje i otpornost zrnatosti kože na delaminaciju koja je gumirana prema postupku prdmetnog pronalaska. [0039] The rubberizing treatment, which is carried out by adding a polymer to the treatment chamber as defined above, creates carbamide bonds between the skin and the polymer itself, which are very strong stable and planar covalent bonds, basically which cannot be obtained by the addition of elastomers of different types, which are mainly responsible for the high quality of tear resistance and the resistance of the grain of the leather to delamination that is rubberized according to the method of the present invention.

[0040] Poželjno, navedeni polimer je polimer izabran od hloroprenskog kaučuka sa karboksilnim grupama (neoprena) (XCR), izoprenskog kaučuka sa karboksilnim grupama (XIR), akrilonitril/butadienskog kaučuka sa karboksilnim grupama (XNBR), stiren/butadienskog kaučuka sa karboksilnim grupama (XSBR), ili njihove smeše i moguće kopolimera stiren/butadienskog kaučuka sa karboksilnim grupama . [0040] Preferably, said polymer is a polymer selected from chloroprene rubber with carboxyl groups (neoprene) (XCR), isoprene rubber with carboxyl groups (XIR), acrylonitrile/butadiene rubber with carboxyl groups (XNBR), styrene/butadiene rubber with carboxyl groups (XSBR), or mixtures thereof and possibly copolymers of styrene/butadiene rubber with carboxyl groups.

[0041] Kada se doda elastomer, okruženje za tretiranje (kupka) je anionsko s alkalnim pH koji se odnosi na izoelektričnu tačku kože, uslove u kojima je prodiranje elastomera u dermis kože promovisano, a nakon minimalnog perioda od 15 min tretmana gumiranja, pomenuto okruženje za tretiranje postaje kiselo sa pH vrednostima poželjno između 2 i 4. Posebno, nakon tretmana gumiranja sledi tretman sušenja u vakuumu sa istovremenim presovanjem. [0041] When the elastomer is added, the treatment environment (bath) is anionic with an alkaline pH related to the isoelectric point of the skin, conditions in which the penetration of the elastomer into the dermis of the skin is promoted, and after a minimum period of 15 min of the rubberizing treatment, said treatment environment becomes acidic with pH values preferably between 2 and 4. In particular, the rubberizing treatment is followed by a vacuum drying treatment with simultaneous pressing.

[0042] Dalje, tretman gumiranja prema pronalasku prati najmanje jedna faza obrade pod kontrolisanom temperaturom i / ili pritiskom. [0042] Furthermore, the rubberizing treatment according to the invention is followed by at least one processing phase under controlled temperature and/or pressure.

[0043] Tačnije, postupak štavljenja prema pronalasku omogućava, nakon tretmana gumiranja, konzervaciju kože u vlažnom okruženju tako da između poslednje vlažne faze navedenog procesa štavljenja i narednog koraka sušenja pomenutog postupka štavljenja , vlažnost kože nikada nije niža od 250% suve težine kože. [0043] More specifically, the tanning process according to the invention enables, after the rubberizing treatment, the conservation of the skin in a humid environment so that between the last wet phase of the mentioned tanning process and the next drying step of the mentioned tanning process, the humidity of the skin is never lower than 250% of the dry weight of the skin.

[0044] Povoljno, očuvanje vlage čuvanjem kože u posudi za tečnosti, uronjene u vodu ili drugu tečnost na vodenoj bazi. [0044] Advantageously, preservation of moisture by storing the leather in a liquid container, immersed in water or other water-based liquid.

[0045] Povoljno, korak sušenja koji obuhvata korak provlačenja kože kroz valjke sa povratnim kretanjem za preradu kože, i korak vakuumskog sušenja. [0045] Advantageously, a drying step comprising a step of passing the leather through reciprocating rollers for processing the leather, and a step of vacuum drying.

[0046] Poželjno, nakon ekstrakcije kože iz pomenutog okruženja za konzervaciju vlažnosti, koža je podvrgnuta procesu sušenja tako da između ekstrakcije kože iz okruženja za konzervaciju vlažnosti i trenutka u kome zaostala vlažnost kože nije veća od 40% suve težine kože u periodu koji ne prelazi dva sata. [0046] Preferably, after the extraction of the skin from the said moisture conservation environment, the skin is subjected to a drying process so that between the extraction of the skin from the moisture conservation environment and the moment when the residual moisture of the skin does not exceed 40% of the dry weight of the skin in a period not exceeding two hours.

Kratak opis crteža Brief description of the drawing

[0047] Ove i druge karakteristike i prednosti postupka pronalaska će se lakše razumeti iz sledećeg opisa specifičnih realizacija,koje su neograničavajuće, uz pomoć priloženih crteža na kojima: [0047] These and other characteristics and advantages of the inventive method will be more easily understood from the following description of specific embodiments, which are non-limiting, with the help of the attached drawings in which:

• Slika 1 prikazuje uvećane fotografije snimljene na mikroskopu dela kože štavljene bez procesa gumiranja: Sl.1a prikazuje uvećanje od 500x, 100 µm, Sl. • Fig. 1 shows magnified photographs taken on a microscope of a section of leather tanned without the gumming process: Fig. 1a shows a magnification of 500x, 100 µm, Fig.

1b prikazuje uvećanje 500x, 20 µm; 1b shows magnification 500x, 20 µm;

• Slika 2 prikazuje uvećane fotografije snimljene na mikroskopu dela kože štavljene postupkom štavljenja kože koji obuhvata postupak gumiranja prema pronalasku: Sl.2a prikazuje uvećanje od 500x, 100 µm, Sl.2b pokazuje uvećanje od 500x, 20 µm; • Fig. 2 shows enlarged photographs taken on a microscope of a part of leather tanned by a leather tanning process comprising a gumming process according to the invention: Fig. 2a shows a magnification of 500x, 100 µm, Fig. 2b shows a magnification of 500x, 20 µm;

• Slika 3 prikazuje rezultate FTIR - ATR analize izvedene na različitim slojevima uzorka kože štavljen prema postupku gumiranja prema pronalasku: Sl. 3a prikazuje površinu zrna, Sl. 3b prikazuje drugi sloj sa zrnataste strane, Sl. 3c prikazuje treći sloj sa zrnataste strane, sl. 3d prikazuje četvrti sloj sa zrnataste strane; • Figure 3 shows the results of FTIR - ATR analysis performed on different layers of a leather sample tanned according to the gumming process according to the invention: Fig. 3a shows the grain surface, FIG. 3b shows the second layer from the grain side, FIG. 3c shows the third layer from the granular side, fig. 3d shows the fourth layer from the grain side;

• Slika 4 prikazuje dijagram upoređivanja spektra dobijenih ATR analizom na površini zrnataste strane gumirane kože prema pronalasku i na površini zrnataste strane kože koja nije gumirana; Figure 4 shows a diagram comparing spectra obtained by ATR analysis on the surface of the grain side of rubberized leather according to the invention and on the surface of the grain side of leather that is not rubberized;

• Na slici 5 prikazani su spektri dobijeni FTIR-ATR analizom na uzorku kože tretirane elastomerima u završnoj fazi (faza štavljenja bez vlaženja): Sl. 5a prikazuje površinu zrna, Sl. 5b prikazuje drugi sloj zrnataste strane, Slika 5c prikazuje treći sloj sa zrnataste strane. • Figure 5 shows the spectra obtained by FTIR-ATR analysis on a sample of leather treated with elastomers in the final phase (tanning phase without wetting): Fig. 5a shows the grain surface, FIG. 5b shows the second layer of the grain side, Figure 5c shows the third layer of the grain side.

Opis poželjnih realizacija Description of desirable implementations

Primer 1 Example 1

[0048] Gomila (hrpa)sirove kože namenjene za proizvodnju kože pogodne za završetak postupcima bojenja, koji se sastoji od 100 kg težine polovine teleta obrijane kože zrnataste strukture u debljini od oko 1 mm, koja je štavljena hromnim štavljenjem i doštavljena sintetičkim taninima, akrilne smole i sintetičkim mastima, podvrgava se u rotirajućoj bačvi (bubnju) sledećim postupcima naknadnog štavljenja koji su navedeni u daljem tekstu. [0048] A pile (pile) of raw hide intended for the production of leather suitable for finishing dyeing procedures, consisting of 100 kg of half-calf weight of shaved skin with a grain structure in a thickness of about 1 mm, which has been tanned by chrome tanning and provided with synthetic tannins, acrylic resin and synthetic fats, is subjected in a rotating barrel (drum) to the following post-tanning procedures listed in the following text.

[0049] Izvodi se prva operacija pranja dodavanjem u bubanj hemijske kupka koja se sastoji od smeše 600 kg vode na 30 ° C i 0,5 kg amonijaka u vodenom rastvoru od 30% i održavanja kože u takvoj sredini oko 30 minuta, nakon čega se kože ocede, pa se pokreće ciklus pranja sa 200 kg vode, a koža se ponovo cedi oko 5 minuta. [0049] The first washing operation is carried out by adding to the drum a chemical bath consisting of a mixture of 600 kg of water at 30 ° C and 0.5 kg of ammonia in a 30% aqueous solution and keeping the skin in such an environment for about 30 minutes, after which the skins are drained, and the washing cycle is started with 200 kg of water, and the skin is drained again for about 5 minutes.

[0050] Zatim se izvodi operacija mašćenja dodavanjem 100 kg vode na 30 ° C i 4 kg hemijskog proizvoda za sintetičko polimerno mašćenje. Nakon 30 minuta obrade dodaje se dodatnih 12 kg hemijskih proizvoda za mašćenje, sintetičkih i prirodnih, koji između ostalog sadrže prirodne sulfite tokom perioda tobrade od 90 dodatnih minuta. Konačno je dodat 1 kg sirćetne kiseline sa kojom se obrada nastavlja dodatnih 30 minuta, nakon čega se kože ocedei isperu sa 300 kg vode. [0050] Then the degreasing operation is performed by adding 100 kg of water at 30 °C and 4 kg of chemical product for synthetic polymer degreasing. After 30 minutes of processing, an additional 12 kg of chemical degreasing products, synthetic and natural, which, among other things, contain natural sulfites are added during the tobrade period of 90 additional minutes. Finally, 1 kg of acetic acid was added, with which the processing continued for an additional 30 minutes, after which the skins were drained and washed with 300 kg of water.

[0051] Zatim je izvedena operacija bojenja dodavanjem kiselih boja u hemijsku kupku i ostavljeno oko 30 minuta. [0051] Then the dyeing operation was performed by adding acid dyes to the chemical bath and left for about 30 minutes.

[0052] Zatim se izvršeno nekoliko ciklusa pranja u trajanju od 5 minuta svaki sa 300 kg vode na 30 ° C kako bi se kože dovele do pH iznad 4,5. [0052] Several washing cycles of 5 minutes each with 300 kg of water at 30 °C were then carried out to bring the hides to a pH above 4.5.

[0053] Zatim je izvedena doštava u trajanju od 10 minuta sa hemijskom kupkom koja se sastoji od 50 kg vode na 30 ° C i 4 kg aldehida za doštavu. [0053] Delivery was then performed for 10 minutes with a chemical bath consisting of 50 kg of water at 30 °C and 4 kg of aldehyde for delivery.

[0054] Nakon toga, u istoj sredini tretiranja, koja je anionska na alkalnom pH, operacija gumiranja se izvodi dodavanjem 24 kg AMBRASAN DAS® (komercijalni naziv smeše karboskilovanih termoplastičnih polimera) i držanjem sredine u kojoj se odvija obrada tokom 20 minuta, nakon čega je dodato 100 kg vode na 50 ° C i 3 kg mravlje kiseline, što čini kupku za tretiranje sa kiselim pH od oko 3,5, u trajanju od 5 minuta, na kraju čega je koža oceđena. [0054] After that, in the same treatment environment, which is anionic at an alkaline pH, the gumming operation is carried out by adding 24 kg of AMBRASAN DAS® (commercial name of a mixture of carboxylated thermoplastic polymers) and holding the environment in which the treatment takes place for 20 minutes, after which 100 kg of water at 50 ° C and 3 kg of formic acid are added, making a treatment bath with an acidic pH of about 3.5, for a duration of 5 minutes, at the end of which the skin is drained.

[0055] Zatim se izvodi dodatna operacija bojenja unošenjem 2 kg kisele boje i održavanje tokom 10 minuta, zatim je dodato 2 kg mravlje kiseline i zadržavanjem dodatnih 30 minuta, nakon čega se kože ocede i operu. [0055] An additional dyeing operation is then carried out by introducing 2 kg of acid dye and maintaining it for 10 minutes, then 2 kg of formic acid is added and kept for an additional 30 minutes, after which the skins are drained and washed.

[0056] Konačno, daljnja operacija mašćrnja se izvodi unosom 200 kg vode na 50 ° C i 4 kg prirodnog sulfitnog proizvoda za mašćenje i održavanje kože u takvoj sredini tratiranja oko 60 minuta, nakon čega su oceđene. Zatim je dodato dodatnih 100 kg vode na 50 ° C i 1 kg mravlje kiseline u trajanju od 60 minuta. [0056] Finally, a further degreasing operation is performed by adding 200 kg of water at 50 ° C and 4 kg of natural sulphite product for degreasing and maintaining the skin in such a treatment environment for about 60 minutes, after which they are drained. An additional 100 kg of water at 50 °C and 1 kg of formic acid were then added for 60 minutes.

[0057] Na kraju kože su oceđene i isprane sa 300 kg vode. Zatim su kože uklonjene iz sredine za obradu (bubanj) i odmah stavljene u cev punu vode u kojoj su zadržane potpoljene dok nisu podvrgnute fazama sušenja. Sušenje se može obaviti u istom proizvodnom pogonu u kojem se odvijalo štavljenje ili u drugom. U ovom drugom slučaju očigledno je suštinski da se cev ili drugi kontejner u kome se čuvaju kože mogu hermetički zatvoriti da se spreči curenje vode tokom transporta. [0057] Finally, the skins were drained and washed with 300 kg of water. Then the skins were removed from the processing environment (drum) and immediately placed in a tube full of water where they were kept underfoot until they were subjected to the drying stages. Drying can be done in the same production facility where tanning took place or in another. In the latter case it is obviously essential that the tube or other container in which the hides are stored can be hermetically sealed to prevent leakage of water during transport.

[0058] Zatim je izveden postupak sušenja koji se odvija u okruženju pod pritiskom ispod atmosferskog pritiska, dok se kože održavaju na temperaturi između 40 ° C i 45° C do dobijanja kože sa apsolutnom vlažnošću u poređenju sa njihovom suvom težinom koja ne prelazi 30%. [0058] Then a drying procedure was carried out, which takes place in a pressurized environment below atmospheric pressure, while the skins are maintained at a temperature between 40°C and 45°C until obtaining skins with an absolute moisture content compared to their dry weight that does not exceed 30%.

[0059] Tačnije, kože su izvučene iz kupke za očuvanja vlažnosti. U ovom trenutku, kože sa stepenom vlažnosti većim od 300% svoje suve težine, podvrgavaju se provlačenja kože kroz valjke sa povratnim kretanjem za preradu kože u mašini koja sadrži nekoliko suprotnih valjka koji istiskuju kožu i najmanje jedan valjak opremljen sečivima tako da češljaju i slažu kožu. [0059] More precisely, the hides were taken out of the bath to preserve humidity. At this point, hides with a moisture content greater than 300% of their dry weight are subjected to passing the hide through reciprocating rollers for processing the hide in a machine containing several opposed rollers which squeeze out the hide and at least one roller equipped with blades to comb and stack the hide.

[0060] Odmah nakon provlačenja kože kroz valjke sa povratnim kretanjem, kože se podvrgavaju vakuumskom sušenju, poželjno u vakum sušnici za višeslojnu kožu. Stepen vakuuma, temperatura ploča i vreme sušenja (4 - 5 minuta) se prilagođavaju tako da se dobiju kože sa rezidualnom vlažnošću koja ne prelazi 40% njihove suve težine. [0060] Immediately after passing the hides through the reciprocating rollers, the hides are subjected to vacuum drying, preferably in a multi-layered leather vacuum dryer. The degree of vacuum, the temperature of the plates and the drying time (4 - 5 minutes) are adjusted in order to obtain skins with a residual moisture not exceeding 40% of their dry weight.

[0061] Zatim je sušenje završeno na sobnoj temperaturi do vrednosti apsolutne vlažnosti od 12% (mereno higrometerom). [0061] Then drying was completed at room temperature to an absolute humidity value of 12% (measured with a hygrometer).

[0062] Potom se dobijene kože mogu podvrgnuti željenim završnim postupcima, konačnim farbanjem. [0062] Then the skins obtained can be subjected to the desired finishing procedures, final painting.

[0063] Prednosti dobijene umetanjem postupka gumenizacije ovog pronalaska u postupku štavljenja kao što je gore opisano, odmah su očite u sledećim tabelama 1.1 i 1.2 u kojima stoji poređenje određenih tehničkih karakteristika štavljene kože spremne za sledeći postupak završne obrade (po mogućnosti farbanje ) proizvedene u skladu sa konvencionalnim postupkom štavljenja i kožom proizvedenom u istu svrhu, ali koja je podvrgnuta procesu gumiranja ovog pronalaska u skladu sa gornjim primerom. [0063] The advantages obtained by inserting the rubberization process of this invention in the tanning process as described above are immediately apparent in the following tables 1.1 and 1.2 in which there is a comparison of certain technical characteristics of tanned leather ready for the next finishing process (preferably dyeing) produced in accordance with the conventional tanning process and leather produced for the same purpose, but which is subjected to the rubberization process of this invention in accordance with the above example.

Tabela 1.1 Table 1.1

Tabela 1.2 Table 1.2

[0064] Konkretno, tabela 1.1 se odnosi na eksperimentalne vrednosti za „Rastezanje i jačina na kidanje zrna - Metoda ispitivanja lomljenjem kuglice (UNI 11308)“, dok se u tabeli 1.2 odnosi na eksperimentalne vrednosti „Određivanje čvrstoće na jednostrano kidanje (UNI EN ISO 3377-1) i dvostrano kidanje (UNI EN ISO 3377-2). " [0064] In particular, table 1.1 refers to the experimental values for "Strength and breaking strength of the grain - Ball breaking test method (UNI 11308)", while in table 1.2 it refers to the experimental values "Determination of strength at one-sided tearing (UNI EN ISO 3377-1) and double-sided tearing (UNI EN ISO 3377-2)."

[0065] Iz tabele se jasno vidi prosečan porast od oko 30% gornjih vrednosti. [0065] The table clearly shows an average increase of about 30% of the above values.

[0066] Gore pomenuto poboljšanje performansi kože, naročito otpornost i jačina na kidanje zrna i zrnaste čvrstoće, dobijeni su zahvaljujući gore opisanom posebnom postupku gumiranja. [0066] The above-mentioned improvement in leather performance, in particular resistance and grain tear strength and grain strength, are obtained thanks to the special gumming process described above.

[0067] Polimer koji je korišćen u proizvodu AMBRASAN DAS® ima odličnu rastvorljivost i elastičnost. U poređenju sa istim polimerom, koji nije karboksilovan, iz kojeg potiče, to je polarni kopolimer koji se dobija podvrgavanjem daljnjem procesu karboksilacije (dodavanje karboksilne grupe-COOH na dienskim vezama) čime se dobijaju polarne karakteristike sa karboksilnim grupama raspoređenim na površini molekula. [0067] The polymer used in the AMBRASAN DAS® product has excellent solubility and elasticity. Compared to the same polymer, which is not carboxylated, from which it originates, it is a polar copolymer that is obtained by undergoing a further carboxylation process (adding a carboxyl group-COOH on diene bonds) which gives polar characteristics with carboxyl groups distributed on the surface of the molecule.

[0068] Svojstvo polarnosti karboksilovanog molekula polimera je od primarne važnosti u procesu gumiranja jer čini polimer više rastvoran u polarnim rastvaračima (kupka za štavljenje je ustvari polarna kupka jer je vodeni rastvor) i može da formira kovalentne karbonat -amidne veze sa proteinskim jedinjenjima kože. U stvari, koža je hemijski sastavljena većim delom iz kolagena čiju strukturalnu jedinicu čini tropokolagen. [0068] The polarity property of the carboxylated polymer molecule is of primary importance in the rubberization process because it makes the polymer more soluble in polar solvents (the tanning bath is actually a polar bath because it is an aqueous solution) and can form covalent carbonate-amide bonds with protein compounds of the skin. In fact, the skin is chemically composed mostly of collagen, the structural unit of which is tropocollagen.

[0069] Tropokolagena nije ništa drugo nego ponavljanje glicin-hidroksiprolina (ili prolin) -X (gde je X bilo koja aminokiselina). Ova ponavljanja sekvenci su spojena vodoničnim vezama da bi formirala neku vrstu trostruke spirale. [0069] Tropcollagen is nothing but a repeat of glycine-hydroxyproline (or proline)-X (where X is any amino acid). These repeat sequences are joined by hydrogen bonds to form a sort of triple helix.

[0070] Različita vlakna tropokolagena su zatim povezana umrežavanjem između dva alizina ili između lizina i alizina. Karboksilovani polimer dodat u kupku za tretiranje će se povezati sa lizinom / alilizinom, što rezultira formiranjem karboamidne veze. [0070] Different tropocollagen fibers are then connected by cross-linking between two allisines or between lysine and allisine. The carboxylated polymer added to the treatment bath will bind to the lysine / allyllysine, resulting in the formation of a carboamide bond.

[0071] Karboamidne veze formirane su planarne stabilne kovalentne veze, gde sve komponente leže na istoj ravni: u stvari, u vezi C-N nema rotacije, za koju se ispostavilo koja je kraća od jednostruke C-C veze [0071] Carboamide bonds are formed by planar stable covalent bonds, where all components lie on the same plane: in fact, there is no rotation in the C-N bond, which turns out to be shorter than the single C-C bond.

[0072] Ova veza je određena SEM analizom koja je izvršena na uzorcima goveđih koža štavljenih u bubnju koristeći konvencionalni recept za dobijanje konvencionalnog hromnog štavljenja (videti slike 1 i slike 1A) i iste kože su štavljene u bubnju pomoću postupka gumiranja sa AMBRASAN DAS® (vidi slike 2 i slike 2A). [0072] This connection was determined by SEM analysis performed on samples of beef hides tanned in a drum using a conventional recipe for obtaining conventional chrome tanning (see figures 1 and figures 1A) and the same hides were tanned in a drum using the gumming process with AMBRASAN DAS® (see figures 2 and figures 2A).

[0073] Iz poređenja morfologija dobijenih sa SEM dva uzorka kože (naročito na slici 1 i slici 2), može se primetiti da je u slučaju gumirane kože (slika 2) raspored kožnih vlakana više ne sledi slučajni i haotični poredak, već su uredno poređani paralelno jedan preko drugog: karboksilovani polimer ispunjava najčešće prazne intersticije dermisa i imobilizuje ih. Kao što se pretpostavlja, u stvari, gumirana koža deluje organizovanije duž celog svog preseka (samim tim i dublje). [0073] From the comparison of the morphologies obtained with the SEM of two skin samples (especially in Figure 1 and Figure 2), it can be observed that in the case of rubberized skin (Figure 2), the arrangement of skin fibers no longer follows a random and chaotic order, but they are neatly arranged parallel to one another: the carboxylated polymer fills the mostly empty interstices of the dermis and immobilizes them. As hypothesized, in fact, the rubberized skin appears more organized along its entire cross-section (and therefore deeper).

[0074] Da bi se podržao ovaj argument, odnosno kuplovanje / impregnacija polimera kroz njegov karboksil u dermisu, pored SEM analize, takođe je sprovedena IR analiza. Naime, FTIR-ATR analiza je rađena direktno na koži uz pomoć tehnike Chemical Imaging. [0074] In order to support this argument, that is, the coupling / impregnation of the polymer through its carboxyl in the dermis, in addition to SEM analysis, IR analysis was also carried out. Namely, the FTIR-ATR analysis was performed directly on the skin with the help of the Chemical Imaging technique.

[0075] Konkretno, koža je „podeljena“ na mnogo tankih komada koji su podvrgnuti FTIR-ATR analizi na površini zrnataste strane da bi se kontrolisala usaglašenost karakterističnih vrhova polimera u slojevima dermisa. [0075] In particular, the skin was "split" into many thin pieces which were subjected to FTIR-ATR analysis on the surface of the grain side to control the alignment of the characteristic peaks of the polymers in the dermis layers.

[0076] Rezultati su pokazali da je karboksilovani polimer u potpunosti prožet u ukupnom preseku kože, kao što je prikazano spektrima sa slike 3. [0076] The results showed that the carboxylated polymer was completely permeated in the total cross-section of the skin, as shown by the spectra of Figure 3.

[0077] Da bi se procenile razlike između negumirane kože i gumirane kože u skladu sa postupkom ovog pronalaska, snimani su spektri na površini zrna, negumiranog uzorka i uzorka gumiranog sa AMBRASAN DAS ® (Sl.4). [0077] In order to evaluate the differences between non-rubberized leather and rubberized leather according to the process of the present invention, spectra were recorded on the grain surface of the non-rubberized sample and the sample rubberized with AMBRASAN DAS ® (Fig. 4).

[0078] Pored toga, iz spektra sa slike 5 je takođe moguće zaključiti značajne razlike između gumirane kože prema postupku iz ovog pronalaska i kože koja je u završnoj fazi tretirana gumiranim proizvodima, iako uz pomoć penetranata. [0078] In addition, from the spectrum of Figure 5 it is also possible to conclude significant differences between the rubberized leather according to the method of the present invention and the leather that was treated in the final phase with rubberized products, albeit with the help of penetrants.

[0079] Kao što se može videti na slici 5, karakteristični pikovi polimera nestaju uklanjanjem površinskog premaza nanetog postupkom završne obrade. [0079] As can be seen in Figure 5, the characteristic peaks of the polymer disappear by removing the surface coating applied by the finishing process.

[0080] Karboksilacija takođe može uticati na moguće obrazovanje vodoničnih veza koje se mogu formirati na površini i u delu dermisa za proizvodnju stabilnije gumirane kože. [0080] Carboxylation can also affect the possible formation of hydrogen bonds that can be formed on the surface and in part of the dermis to produce a more stable rubberized skin.

[0081] Na sposobnost karboksilovanog polimera da formira karboamidne veze duž cele debljini tretirane kože je pod uticajem okruženja za tretiranje. U stvari, priprema kupke za tretiranje u početku anionska i alkalna sprečava taloženje proizvoda koji sadrži elastomerni polimer koji je i dalje dostupan za prodiranje u kožu i stvaranje veza sa ovim poslednjim. Dalje, prodiranje polimera (polaran) u kožu snažno je podstaknuta anionsko prirodom kupke za tretiranje, jer osnovni pH kupke za tretiranje daje pozitivno naelektrisanje koži i pospješuje prodiranje polimera koji je negativno polarizovan . [0081] The ability of the carboxylated polymer to form carbamide bonds throughout the thickness of the treated skin is influenced by the treatment environment. In fact, preparing the treatment bath initially anionic and alkaline prevents the deposition of a product containing an elastomeric polymer that is still available to penetrate the skin and form bonds with the latter. Furthermore, the penetration of the polymer (polar) into the skin is strongly encouraged by the anionic nature of the treatment bath, because the basic pH of the treatment bath gives a positive charge to the skin and promotes the penetration of the negatively polarized polymer.

[0082] Nakon toga, kupka za tretiranje postaje kisela, što stvara najbolje uslove za stvaranje karboamidnih veza između kože i elastomernog polimera. [0082] After that, the treatment bath becomes acidic, which creates the best conditions for the formation of carbamide bonds between the skin and the elastomeric polymer.

[0083] "Gumirana" koža dobijena postupkom gumiranja prema pronalasku ima mehaničke osobine vrlo slične onima elastomera koji se nalazi u njoj. Međutim, hemijske veze koje koži daju takve karakteristike, učvršćuju se samo gubitkom vlažnosti kože, dokle god koža ostane vlažna može se obraditi i njen oblik se može menjati. Kako koža gubi vlagu, unutrašnje hemijske veze se učvršćuju i koža dobija oblik tipičan za elastomer koji se nalazi u njoj. Iz ovog razloga je od suštinskog značaja da se ne samo stvarna faza sušenja, već i svaki gubitak vlage kože posle tretmana gumiranjem dogodi na kontrolisan način. Prema ovom pronalasku, između završetka procesa štavljenja u vlažnom okruženju i početka faze sušenja, koža se održava uronjena u vodu ili drugu pogodnu vodenu tečnost, tako da hemijske veze koje daju gumiranoj koži njena posebna svojstva nastavite da budu "opuštene" dok proces sušenja ne započne, tokom koga se koža istegne i ostavi da leži. Na taj način se efikasno izbegava stvaranje nabora ili drugih deformacija, a gumirana koža je mikroskopski i makroskopski homogena. [0083] The "rubberized" leather obtained by the rubberizing process according to the invention has mechanical properties very similar to those of the elastomer contained therein. However, the chemical bonds that give the skin such characteristics are only strengthened by the loss of skin moisture, as long as the skin remains moist it can be processed and its shape can be changed. As the skin loses moisture, the internal chemical bonds solidify and the skin takes on the shape typical of the elastomer found within it. For this reason, it is essential that not only the actual drying phase, but also any loss of skin moisture after the gumming treatment occurs in a controlled manner. According to the present invention, between the end of the wet tanning process and the beginning of the drying phase, the leather is kept immersed in water or other suitable aqueous liquid so that the chemical bonds which give the rubberized leather its special properties continue to be "relaxed" until the drying process begins, during which the leather is stretched and left to lie. In this way, the creation of wrinkles or other deformations is effectively avoided, and the rubberized leather is microscopically and macroscopically homogeneous.

Primer 2 Example 2

[0084] Hrpa sirove kože od wet-blue kože sastoji se od 100 kg suve težine polovine teleće francuske nubuke, koja je štavljena hromnim štavljenjem i doštavljena sintetičkim i biljnim taninima i omašćena sa prirodnim mastima, podvrgnuta je u bubnju daljom obradom doštavom navedenim u daljem tekstu. [0084] A pile of wet-blue leather rawhide consists of 100 kg dry weight of half-calf French nubuck, which is tanned by chrome tanning and supplied with synthetic and vegetable tannins and greased with natural fats, is subjected in a drum to further processing as specified below.

[0085] Izvodi se prva operacija ponovnog vlaženja unošenjem u bubanj hemijsku kupatilu koje se sastoji od smeše 600 kg vode pri 30 ° C i 0,5 kg amonijaka u vodenom rastvoru od 30% i čuvanja kože u u tom okruženju oko 30 minuta, nakon čega se kože ocede, pokrenut je ciklus pranja sa 200 kg vode i kože se ponovo cede oko 5 minuta. [0085] The first operation of rewetting is carried out by introducing into the drum a chemical bath consisting of a mixture of 600 kg of water at 30 ° C and 0.5 kg of ammonia in a 30% aqueous solution and keeping the skin in that environment for about 30 minutes, after which the skins are drained, a washing cycle with 200 kg of water is started and the skins are squeezed again for about 5 minutes.

[0086] Zatim se izvodi operacija mašćenja dodavanjem 100 kg vode na 30 ° C i 6 kg smeše polimernih sintetičkih agenasa za mašćenje. Nakon 30 minuta obrade dodaje se dodatnih 25 kg hemijskih proizvoda za mašćenje, sintetičkih i prirodnih, koji između ostalog sadrže amfoterne prirodne agense za mašćenje i sulfatne prirodne agense za mašćenje u periodu tretiranjaa od 90 dodatnih minuta. Konačno, dodat je 1 kg sirćetne kiseline sa kojom se nastavlja sa obradom još 30 minuta, nakon čega se kože ocede i isperu sa 300 kg vode na 30 ° C. [0086] Then the degreasing operation is carried out by adding 100 kg of water at 30 °C and 6 kg of a mixture of polymeric synthetic agents for degreasing. After 30 minutes of processing, an additional 25 kg of chemical degreasing products, synthetic and natural, are added, which, among other things, contain amphoteric natural degreasing agents and sulfated natural degreasing agents for a treatment period of 90 additional minutes. Finally, 1 kg of acetic acid was added, with which the processing continued for another 30 minutes, after which the skins were drained and washed with 300 kg of water at 30 °C.

[0087] Zatim se izvodi konvencionalna operacija bojenja. [0087] A conventional dyeing operation is then performed.

[0088] Zatim je izedeno nekoliko ciklusa pranja u trajanju od 5 minuta svaki sa 300 kg vode na 30 ° C da bi dovele pH kože do iznad 4,5. [0088] Several washing cycles of 5 minutes each with 300 kg of water at 30 °C were then carried out to bring the pH of the skin to above 4.5.

[0089] Zatim se vrši doštava u trajanju od 10 minuta sa hemijskom kupkom koja se sastoji od 50 kg vode na 30 ° C i 4 kg aldehida za ponovno štavljenje. [0089] Then delivery is made for 10 minutes with a chemical bath consisting of 50 kg of water at 30 ° C and 4 kg of aldehyde for re-tanning.

[0090] Nakon toga, u istom okruženju za obradu, postupak gumiranja se izvodi dodavanjem 20 kg termoplastičnog karboksilovanog elastomernog kopoimera i vreme trajanja obrade od 30 minuta, nakon čega se doda 100 kg vode na 50 ° C i 3 kg mravlje kiseline u trajanju od još 10 minuta, nakon čega se kože cede. [0090] After that, in the same processing environment, the gumming process is performed by adding 20 kg of thermoplastic carboxylated elastomeric copolymer and a processing time of 30 minutes, after which 100 kg of water at 50 ° C and 3 kg of formic acid are added for another 10 minutes, after which the skins are squeezed.

[0091] Konačno, jedna poslednja hemijska operacija se izvodi unosom 100 kg vode na 50 ° C i 1 kg mravlje kiseline, u trajanju od 60 minuta. [0091] Finally, one last chemical operation is performed by adding 100 kg of water at 50 ° C and 1 kg of formic acid, for 60 minutes.

[0092] Na kraju se kože ocede i isperu sa 300 kg vode. Kože se zatim izvlače iz bubnja i čuvaju kao što je opisano u prethodnom primeru. [0092] Finally, the skins are drained and washed with 300 kg of water. The skins are then removed from the drum and stored as described in the previous example.

[0093] Zatim se izvodi postupak sušenja. U ovom slučaju vakuumsko sušenje se odvija u mašini za sušenje u vakumu u kojoj su ploče između kojih je koža položena odgovarajuće trodimenzionalno oblikovane tako da predstavljaju odgovarajuće kalupe i kontra kalupe. Na ovaj način, faza presovanja kože odvija se istovremeno sa korakom vakuumskog sušenja sa očiglednim prednostima sa stanovišta ekonomičnosti celokupnog procesa. U stvari, iz vakuumske sušinice dobija se gumirana koža koja je trodimenzionalno oblikovana i / ili presovana šarenim uzorcima, logotipovima i drugim grafičkim simbolima. [0093] Then the drying procedure is carried out. In this case, vacuum drying takes place in a vacuum drying machine in which the plates between which the skin is laid are suitably three-dimensionally shaped to represent the corresponding molds and counter molds. In this way, the skin pressing phase takes place simultaneously with the vacuum drying step with obvious advantages from the point of view of the economy of the entire process. In fact, the vacuum dryer produces rubberized leather that is three-dimensionally shaped and/or pressed with colorful patterns, logos and other graphic symbols.

[0094] Gornji postupak sušenja u vakuumu i istovremenog presovanja je konvencionalno poznat, ali je posebno povoljan zahvaljujući upotrebi gumirane kože u skladu sa predmetnim pronalaskom. U stvari, moguće je vršiti presovanje sa parametrima temperature i pritiska mnogo nižim nego što je slučaj sa presovanjem u procesu završne obrade, zahvaljujući činjenici da koža i dalje ima visok stepen vlažnosti koji značajno smanjuje vrednosti plastifikacije temperature / pritiska polimera koji se nalazi u njemu. Zatim se tokom faze sušenja gumirana koža može presovati, deformišući je sa visokim stepenom preciznosti i definicije, a nakon sušenja oblik zbog homogenog prisustva elastomera duž cele debljine kože omogućava da se očuvaju oblik i šara. Pored toga, izvođenje presovanja na niskim temperaturama (prosečna 30-65 ° C umesto 90-130 ° C) sprečava toplotni stres površine kože uzrokujući stvrdnjavanje, gorenje ili druga oštećenja. [0094] The above procedure of vacuum drying and simultaneous pressing is conventionally known, but is particularly advantageous thanks to the use of rubberized leather according to the present invention. In fact, it is possible to perform pressing with temperature and pressure parameters much lower than the case of pressing in the finishing process, thanks to the fact that the skin still has a high degree of humidity that significantly reduces the temperature / pressure plasticization values of the polymer contained in it. Then, during the drying phase, the rubberized leather can be pressed, deforming it with a high degree of precision and definition, and after drying, the shape due to the homogeneous presence of elastomer along the entire thickness of the leather allows the shape and pattern to be preserved. In addition, performing pressing at low temperatures (average 30-65 ° C instead of 90-130 ° C) prevents thermal stress of the leather surface causing hardening, burning or other damage.

[0095] Konačno, dobijena gumirana koža može da bude podvrgnuta željenim završnim postupcima. [0095] Finally, the obtained rubberized leather can be subjected to the desired finishing procedures.

[0096] Prednosti dobijene umetanjem postupka gumeniranja pronalaska u postupku štavljenja kao što je gore opisano, odmah su očigledne u sledećim tabelama 2.1 i 2.2 u kojima se vrši poređenje vrednosti nekih tehničkih osobina štavljene kože od poluproizvoda wet blue proizvedene u skladu sa konvencionalnim postupkom štavljenja i koža proizvedena za istu namenu, ali koja je podvrgnuta postupku gumiranja prema predmetnom pronalasku prema gornjem primeru. Kao što je već navedeno u prethodnom primeru, što se tiče ove poređenja, štavljena koža proizvedena konvencionalnim postupkom štavljenja je opterećenje kore bivših wet blue koža kao što je korišćeno u postupku štavljenja opisanom u primeru 2, kojem je podvrgnuta istim koracima postupka koji su opisani u primeru 2, osim postupka gumiranja koji u ovom primeru obuhvata: dodavanje 20 kg termoplastičnog karboksilovanog elastomernog kopoimera i održavanje tretmana 30 minuta, nakon čega je dodato 100 kg vode na 50 ° C i 3 kg mravlje kiseline u trajanju od još 10 minuta, nakon čega se kože cede. [0096] The advantages obtained by inserting the gumming process of the invention into the tanning process as described above are immediately apparent in the following tables 2.1 and 2.2 in which a comparison is made of the values of some technical properties of wet blue semi-tanned leather produced according to the conventional tanning process and leather produced for the same purpose, but subjected to the gumming process according to the subject invention according to the above example. As already stated in the previous example, as far as this comparison is concerned, the tanned leather produced by the conventional tanning process is the loading of the bark of the former wet blue hides as used in the tanning process described in Example 2, subjected to the same process steps as described in Example 2, except for the rubberizing process which in this example includes: adding 20 kg of thermoplastic carboxylated elastomeric copolymer and maintaining the treatment for 30 minutes, after which 100 kg of water is added at 50 ° C and 3 kg of formic acid for another 10 minutes, after which the skins are squeezed.

Tabela 2.1 Table 2.1

Tabela 2.2 Table 2.2

[0097] Konkretno, tabela 2.1 se odnosi na eksperimentalne vrednosti za „Otpornost i jačina na kidanje zrna - Metoda ispitivanja lomljenjem kuglice (UNI 11308)“, dok se Tabela 2.2 odnosi na eksperimentalne vrednosti „Određivanje čvrstoće na kidanje -jednostrano kidanje (UNI EN ISO 3377-1) i dvostrano kidanje (UNI EN ISO 3377-2)." [0097] In particular, Table 2.1 refers to the experimental values for "Resistance and tear strength of grains - Ball breaking test method (UNI 11308)", while Table 2.2 refers to the experimental values "Determination of tear strength - single-sided tear (UNI EN ISO 3377-1) and double-sided tear (UNI EN ISO 3377-2)."

[0098] Iz tabele je jasno vidljivo prosečno povećanje od oko 30% gornjih vrednosti. [0098] From the table it is clearly visible an average increase of about 30% of the above values.

[0099] Dalje, čak je i presovanje u procesu završne obrade posebno povoljno kod kože proizvedene postupkom gumiranja prema pronalasku, jer je moguće dobiti utisnut motiv vrlo visoke definicije zahvaljujući fizičkim i mehaničkim svojstvima elastomernog polimera koji je sadržan u koži koje u osnovi usvaja sâma koža, uz moguće prednosti u sprečavanju falsifikovanja. [0099] Furthermore, even pressing in the finishing process is particularly advantageous for leather produced by the gumming process according to the invention, because it is possible to obtain an embossed motif of very high definition thanks to the physical and mechanical properties of the elastomeric polymer contained in the leather which is basically adopted by the leather itself, with possible advantages in preventing counterfeiting.

[0100] Očigledno, gore opisani postupci su samo dati kao primer, a ne ograničavajući, a postupak gumiranja prema ovom pronalasku, kao i postupak štavljenja koji čini deo, takođe se značajno mogu razlikovati. [0100] Obviously, the processes described above are merely exemplary and not limiting, and the gumming process of the present invention, as well as the tanning process of which it is a part, may also vary significantly.

[0101] Zapravo, koža koja se tokom postupka štavljenja može podvrgnuti gore opisanom postupku gumiranja može nastati od bilo koje kopnene, morske, amfibijske ili pernaate životinje, a proces štavljenja je optimizovan kao funkcija vrste kože koja se obrađuje i estetske i funkcionalne osobine kože koja se dobija, a koja zauzvrat može da bude pogodna za realizaciju velikih i malih kožnih proizvoda, obuće, gornjih delova i đona za obuću, odeću, nameštaj, krzno, uvezivanje knjiga, tehničke predmete, presvlake, itd. [0101] In fact, the leather that can be subjected to the above-described gumming process during the tanning process can come from any terrestrial, marine, amphibian or feathered animal, and the tanning process is optimized as a function of the type of leather being processed and the aesthetic and functional properties of the leather obtained, which in turn can be suitable for the realization of large and small leather products, footwear, shoe uppers and soles, clothing, furniture, fur, bookbinding, technical items, upholstery, etc.

[0102] Postupak gumiranja se povoljno izvodi pomoću bubnjeva unutar kojih se može stvoriti odgovarajuće okruženje za hemijsku obradu, a kontekstualno su u stanju da mehanički deluju na kožu. Međutim, postupak gumiranja se takođe može primeniti u drugim mašinama za faze vlažnog štavljenja, kao što su stacionarni rezervoari, kolutovi, mašine za pranje veša, mešalice ili drugi odgovarajući spremnici. [0102] The gumming process is advantageously carried out by means of drums within which a suitable environment for chemical processing can be created, and contextually they are able to mechanically act on the leather. However, the gumming process can also be applied in other machines for the stages of wet tanning, such as stationary tanks, reels, washing machines, mixers or other suitable containers.

[0103] Upotrebljeni elastomeri su pogodno karboksilovani polimeri odabrani od hloroprenskog kaučuka sa karboksilnim grupama (neoprena) (XCR), izoprenskog kaučuka sa karboksilnim grupama (XIR), akrilonitril/butadienskog kaučuka sa karboksilnim grupama (XNBR), stiren/butadienskog kaučuka sa karboksilnim grupama (XSBR), ali se mogu koristiti i drugi različiti karboksilatni termoplastični elastomeri. [0103] The elastomers used are suitably carboxylated polymers selected from chloroprene rubber with carboxyl groups (neoprene) (XCR), isoprene rubber with carboxyl groups (XIR), acrylonitrile/butadiene rubber with carboxyl groups (XNBR), styrene/butadiene rubber with carboxyl groups (XSBR), but other various carboxylate thermoplastic elastomers can be used.

[0104] Gore navedeni elastomeri, rastvorni ili rastvoreni u vodi, koriste se pojedinačno ili u njihovoj smeši ili u smeši sa drugim vrstama proizvoda. [0104] The above-mentioned elastomers, soluble or dissolved in water, are used individually or in their mixture or in a mixture with other types of products.

[0105] Poželjno, postupak gumiranja se odvija istovremeno ili uzastopno u postupcima ponovnog štavljenja, bojenja ili mašćenja. Međutim, postupak pronalaska se takođe može izvesti istovremeno ili uzastopno u jednoj ili više pripremnih operacija, ili čak istovremeno ili uzastopno u operaciji štavljenja, odkišeljavnja ili fiiksiranja. [0105] Preferably, the gumming process takes place simultaneously or sequentially in the processes of re-tanning, dyeing or oiling. However, the process of the invention can also be carried out simultaneously or sequentially in one or more preparatory operations, or even simultaneously or sequentially in the operation of tanning, deacidification or fixing.

[0106] U svakom slučaju, poželjno je da, u vreme dodavanja elastomera, sredina za obradu bude anionska sa alkalnim pH u odnosu na izelektričnu tačku kože i da, posle toga, na određeno vreme obrade, po mogućnosti od najmanje 15 minuta, pH postane kiseo (i dalje u odnosu na izoelektričnu tačku kože), na primer dodavanjem kiselina kao što je mravlje kiselina, sirćetna kiselina ili druge organske kiseline, poželjno kratkog lanca. U takvim uslovima se inicijalno potpomaže prodiranje elastomera u dermis kože, a potom njeno fiksiranje i korišćenje. [0106] In any case, it is preferable that, at the time of adding the elastomer, the processing medium is anionic with an alkaline pH in relation to the isoelectric point of the skin and that, after that, for a certain processing time, preferably of at least 15 minutes, the pH becomes acidic (still in relation to the isoelectric point of the skin), for example by adding acids such as formic acid, acetic acid or other organic acids, preferably short chain. In such conditions, the penetration of the elastomer into the dermis of the skin is initially supported, and then its fixation and use.

[0107] Minimalne količine elastomera (odnosi se na suvu težinu) korišćenih u procesu gumiranja prema pronalasku, koje se odnose na težinu kože, jednake su 0,1% u poređenju sa težinom sveže soljene kože ili 0,5% u poređenju sa težinom vlažne obrijane kože ili 1% u poređenju sa suvom težinom. Očigledno je da se količine elastomera mogu koristiti takođe mnogo veće od onih naznačenih, u zavisnosti od željenih svojstava kože. Na primer, posebno značajna svojstva se dobijaju sa količinama elastomera jednakim 1% težine sveže soljene kože ili 5% u poređenju sa težinom vlažne obrijane kože ili 10% u poređenju sa suvom težinom. [0107] The minimum amounts of elastomers (referred to dry weight) used in the gumming process according to the invention, referred to the weight of the leather, are equal to 0.1% compared to the weight of freshly salted leather or 0.5% compared to the weight of wet shaved leather or 1% compared to the dry weight. Obviously, amounts of elastomer can be used also much higher than those indicated, depending on the desired properties of the leather. For example, particularly significant properties are obtained with amounts of elastomer equal to 1% of the weight of freshly salted leather or 5% compared to the weight of wet shaved leather or 10% compared to the dry weight.

[0108] Kože su ostavljene u hemijskoj kupki koja sadrži elastomere, tokom određenog vremena, što je funkcija kožnog proizvoda koji se proizvodi, a poželjno najmanje 15 minuta. To omogućava dovoljan prodor elastomera u unutrašnje slojeve kože. Međutim, koncentracija elastomera u hemijskoj kupelji i trajanje tretmana su promenljivi u zavisnosti od vrste i osobina kožnog proizvoda koji se traže i / ili žele. [0108] The skins are left in a chemical bath containing elastomers for a certain time, which is a function of the leather product being produced, preferably at least 15 minutes. This enables sufficient penetration of the elastomer into the inner layers of the skin. However, the concentration of the elastomer in the chemical bath and the duration of the treatment are variable depending on the type and properties of the leather product that are sought and/or desired.

[0109] Postupak gumiranja se može izvesti još uvek u vlažnoj fazi, čak i posle operacija završne obrade. Naročito je u ovom slučaju posebno korisno da nakon postupka gumiranja sledi postupak sušenja koji se odvija pod kontrolisanom temperaturom i / ili pritiskom. Posebno, sušenje može biti korisno korišćenjem vakuumskih sušnica ili komora za sušenje. [0109] The gumming process can be carried out still in the wet phase, even after the finishing operations. Especially in this case, it is especially useful that after the gumming process, the drying process takes place under controlled temperature and/or pressure. In particular, drying can be beneficial using vacuum dryers or drying chambers.

[0110] Kože koje su prošle postupak gumiranja su konzistentne, elastične, gumirane, izuzetno su pogodne za štampanje, visoku definiciju, imaju odličnu otpornost na kidanje i jačinu na kidanje zrna (grain) i poboljšanu mehaničku čvrstoću uopšte, bolju otpornost na visoke temperature i pritisci, bolja otpornost na apsorpciju vode i na curenje. Kožni artikli za glatke predmete, čini se da imaju zrno koje prijanja a nije nabubrilo; kože sa bubnjevim zrnom odlikuju se time što poprimaju vrlo pun i prirodan izgled. Uz to, mesnate kože sa bočne strane (ili ostaci) predstavljaju naročitu kompaktnost. [0110] Skins that have undergone the rubberizing process are consistent, elastic, rubberized, extremely suitable for printing, high definition, have excellent resistance to tearing and strength to tearing grain (grain) and improved mechanical strength in general, better resistance to high temperatures and pressures, better resistance to water absorption and leakage. Leather goods for smooth items, appear to have a grain that adheres and is not swollen; leathers with a drum grain are characterized by the fact that they take on a very full and natural appearance. In addition, the fleshy skins on the side (or scraps) represent a special compactness.

Claims

Patent claims

1. The tanning process includes a rubbering process in which during at least the wet phase of the tanning process elastomers are present in the processing environment, characterized in that the given elastomers are a polymer or a mixture of polymers from the family of carboxylate thermoplastic elastomers, which are present in an amount of the dry weight of the product containing elastomers of at least 0.1% by weight of fresh salted hides or 0.5% by weight of wet shaved hides or 1% by weight of dry hides, wherein the treatment environment is mentioned at the beginning anionic at an alkaline pH relative to the isoelectric point of the skin and after a minimum period of 15 min of gumming treatment, said treatment environment becomes acidic, wherein said gumming treatment is followed by a vacuum drying treatment with simultaneous pressing.

2. The tanning process according to claim 1, characterized in that the elastomer is a mixture of elastomers selected from chloroprene rubber with carboxyl groups (neoprene) (XCR), isoprene rubber with carboxyl groups (XIR), acrylonitrile/butadiene rubber with carboxyl groups (XNBR), styrene/butadiene rubber with carboxyl groups (XSBR).

3. The tanning process according to one of the previous requirements, indicated by the fact that the treatment medium is acidified by the addition of a product containing at least one formic acid and acetic acid, wherein the said product is added in an amount that reaches a pH of less than 4.

4. Tanning procedure according to one of the previous requirements, characterized by the fact that after the gumming procedure, drying operations follow, at the end of which the leather has a residual moisture that does not exceed 40% in relation to their dry weight.

5. The tanning process according to the previous claim, characterized in that between the last wet phase of the tanning process, after the gumming operation and the drying operation, the hides are stored in a humid environment so that between the last wet phase of the tanning process and the drying step of the tanning process, the moisture content of the hides is never less than 250% of the dry weight of the hides.

6. The tanning process according to the preceding patent claim, characterized in that it is stored in a humid environment with the skin being kept in containers for liquids immersed in water or other water-based liquids.

7. The tanning process according to the previous claim, characterized in that between the removal of the leather from the wet preservation environment and the time of the drying process in which the remaining moisture of the leather does not exceed 40% of the dry weight of the leather, does not last longer than two hours.

8. The tanning process according to claims 5 and 6, characterized by the fact that the drying process includes the operations of passing the hides through rollers with a return movement and successive vacuum drying operations, from the removal of the hides from the moist environment for conservation and the end of the vacuum drying operations, does not last longer than two hours.

9. A tanning process according to one of the preceding claims, characterized in that the gumming process is carried out in a drum or washing machine, or similar wet phase machines, wherein said elastomer is added to a chemical treatment bath located in said drum or washing machine.

10. Rubberized leather, characterized in that it is obtained by a tanning process according to one of the preceding claims.

11. Leather items made of rubberized leather or containing elements of rubberized leather, characterized by the fact that they are obtained by tanning according to one of the previous requirements.