US 20190177913A1 ( 19) United States (12 ) Patent Application Publication ( 10) Pub . No. : US 2019 /0177913 A1 Basilio et al. ( 43 ) Pub . Date : Jun . 13 , 2019 ( 54 ) REMOVAL OF STICKIES IN THE 2) U . S . CI. RECYCLING OF PAPER AND PAPERBOARD CPC . .. .. .. .. D21C 5 /022 ( 2013 .01 ) ; D214 1 /00 ( 2013. 01 ); D21H 11/ 14 ( 2013 .01 ) (71 ) Applicant: Thiele Kaolin Company, Sandersville , GA (US ) (72 ) Inventors : Cesar I . Basilio , Milledgeville , GA (57 ) ABSTRACT (US ) ; Steven W . Sheppard , Sandersville , GA (US ) Removal of stickies from waste paper and paperboard is obtained with the use of a modified kaolin -based stickies (21 ) Appl. No. : 15 /834 , 497 removal composition . The modified kaolin - based stickies ( 22) Filed : Dec . 7 , 2017 removal composition is produced by modifying the kaolin clay, separating the modified kaolin clay from the non Publication Classification reactive kaolin clay, and then adding a nonionic surfactant to (51 ) Int. Ci. the modified kaolin -based particles . Removal of stickies is D21C 5 / 02 ( 2006 .01 ) improved by the use of this modified kaolin -based stickies D21H 11/ 14 (2006 . 01) removal composition during the recycling of the waste paper D21 ) 1 / 00 ( 2006 . 01 ) and paperboard . US 2019 /0177913 A1 Jun . 13 , 2019 REMOVAL OF STICKIES IN THE ies control in which stickies are removed from the product RECYCLING OF PAPER AND PAPERBOARD would be a superior solution than those presented in the prior art, because such a method would not involve the use of TECHNICAL FIELD additional chemicals, polymers, dispersants or other addi [ 0001] The present invention relates to the removal of tives , at an additional production cost , and would provide a stickies from waste paper and paperboard . In a more specific more comprehensive solution to the paper quality problems aspect , this invention relates to the use of a modified caused by stickies rather than just masking their presence in kaolin -based composition for the removal of stickies from the product . waste paper and paperboard . [ 0005 ] U . S . Pat. No . 6 ,210 , 526 ( to Pohlen ) discloses a method of inhibiting and eliminating stickies from waste BACKGROUND OF THE INVENTION paper through the addition of hydrophobized synthetic or [0002 ] The recovered fiber from waste paper and paper naturalmineral to a waste paper pulp wherein the stickies are board such as old newspaper ( ONP ) , old magazine ( OMG ) , removed together with the ink and dirt particles during mixed office waste (MOW ) , sorted white ledger (SWL ) , flotation deinking . The hydrophobized synthetic or natural sorted office paper (SOP ) , and old corrugated carton (OCC ) mineral is added in the form of a fiber containing slurry . The has become a principal source of raw material for making method disclosed by Pohlen only works in recycling opera paper in the US and Europe , with significant growth in tions that use flotation , which limits its application . For China and other Asian countries . Although the production of example , the recycling of paperboard does not use flotation , recycled newsprint and printing paper has been significantly and so the Pohlen method would not be acceptable for reduced in the US and Europe , those of recycled tissue, stickies removal in such operations . brown and paperboard grades have continued to grow . [ 0006 ] U . S . Pat. No . 5 ,540 , 814 ( to Curtis et al. ) describes [ 0003] One of the current issues in paper recycling is the a method of reducing stickies and removing ink from waste quality of the recovered paper and paperboard . With single paper fiber wherein a cationic kaolin is added to a waste stream recycling being more common now , the quality of the paper fiber under conditions such that the kaolin attaches to recovered paper and paperboard has been getting poorer. It the stickies or the ink and the stickies or ink are then has also resulted in stickies issues being more prevalent in removed using a centrifugal cleaner due to the stickies or ink paper recycling operations . In the paper industry, stickies now having a higher specific gravity . The cationic kaolin is refers to a mixture of organic contaminants used to join the prepared from anionic kaolin and a cationic polymer , such as paper substrate to other materials . This includes adhesives , epicholorohydrin polymer, poly ( dialkyldiallylammonium hot melts , wax , coating binders , wood resins , rosins , and wet halide ) , poly ( diallydimethylammonium chloride ) or poly strength resins. The problem of stickies is now a global issue alkylester of a tertiary amine halide . However , the presence that affects recycling all types of paper and paperboard . of cationic polymers significantly affects the wet end part of Stickies deposit on machine surfaces, fabrics , wires , felts papermaking . In addition , the presence of cationic polymers and rolls , which leads to machine breaks. These operational in stock preparation where fractionation is used is detrimen problems associated with stickies result in excessive down tal to the separation of the long fiber from the short fiber . times as a result of an increase in maintenance, cleaning , Thus, most paper and paperboard recycling operations avoid replacing equipment, and breaks. The issue with stickies not the use of any material in the recycling operation that only affects the operational side of recycling but the quality contains cationic or anionic polymers . As such , the Curtis of the product itself. On the product side, stickies can cause method also has limited use in certain stickies removal holes, sheet defects , high dirt count, and problems in con operations . verting which all cause an increase in breakages and rejects . [ 0007 ] U . S . Pat. No . 6 ,013 , 157 ( to Li et al. ) discloses a Both problems reduce process efficiency and increase pro chemical deinking agent for controlling froth and reducing duction costs and contribute to a decrease in machine stickies during flotation wherein the deinking agent consists productivity . Thus, there is a strong need to solve the stickies from nonionic surfactant represented by the following for problem . mula : [0004 ] Current stickies control used in industry by its very nature just “ cures the symptoms. ” This approach focuses on R - C6H40 – C2H40 ) m — ( C3H30 )n - ( C4H20 ) — R ! minimizing the effect of the stickies on the paper machine and in the final product . Current stickies control methods fatty acid esters of sorbitan , certain alkoxylated fatty acid include passivation , dispersion , fixation , and detackification . esters of sorbitan , polypropylene glycols , and a combination In passivation , the stickies are stabilized through the use of of at least two of the aforesaid materials . However , similar an additive such as talc , bentonite , smectite , and other to the method disclosed by Pohlen , the Limethod is limited minerals as disclosed in U . S . Pat. Nos . 4 , 923 , 566 ; 5 ,798 , to recycling operations that use flotation , and so this method 023 ; 8 ,691 , 052 ; 8 ,840 , 761; and 9 ,017 ,519 . Stickies control would not be acceptable for stickies removal in operations by dispersion is achieved through the use of anionic or that do not involve flotation . nonionic dispersants . In terms of stickies control through [ 0008 ] U . S . Pat. No. 8 ,043 , 473 (to Yuzawa et al. ) discloses fixation into the fibers , this is typically carried out using a method of making deinked pulp using anhydride of cationic polymers as described in U . S . Pat. No . 7 ,407 , 561 . crystalline layered silicate . This patent claims to improve the For stickies control via detackification , various chemical deinking of waste paper but prevents excessive reduction in compounds, enzymes, and chemically structured minerals as the size of the stickies , resulting in a deinked pulp with disclosed in U . S . Pat. Nos. 4 , 886 ,575 ; 4 , 956 ,051 ; 5 , 080 ,759 ; reduced stickies content. However , the Yuzawa method is 6 ,471 , 826 ; 8 ,048 ,268 ; 8 , 388 ,806 ; 8 , 784 ,606 ; 8 ,784 ,613 ; limited to deinking applications and requires deinking sur 9 ,057 , 155 are generally used . However , a method for stick factants in order to be effective . In addition , this method is US 2019 /0177913 A1 Jun . 13 , 2019 not applicable to the recycling of paperboard . Therefore , the inefficient since most of the stickies are too small to be Yuzawa method is not acceptable for certain stickies removed even by the finest screens . Also , most of the removal operations . stickies such as hot melts are semi- solid at typical operating [ 0009 ] U . S . Pat . Nos. 8 ,052 , 837 and 8 ,815 , 051 (both to temperatures during recycling , so under prior art methods Basilio et al. ) showed that a modified kaolin -based deinking these stickies are able to extrude and pass through holes and reagent developed for use in the flotation deinking of slots together with paper fiber . In the case of conventional recovered paper can improve the removal of inks, dirts , and centrifugal cleaning, the separation of stickies is based on other contaminants . In the current invention , this technology the difference in the density between the stickies and the has been developed further to produce a modified kaolin paper fiber . The prior art methods of removing stickies by based composition for removing stickies from waste paper centrifugal cleaning are also inefficient since the density of and paperboard which does not suffer from the drawbacks of most stickies is very close to that of fiber. But by collecting prior art methods for stickies removal . and agglomerating the stickies with the modified kaolin [ 0010 ] Moreover , many current methods of stickies based composition of this invention to form bigger particles removal, including those described by the Basilio U . S . Pat. with a higher density, the present invention provides a means Nos. 8 , 052 ,837 and 8 , 815 ,051 , are not suitable for one to make centrifugal cleaning more efficient in removing additional means of stickies removal, that involving a wash stickies. Finally , unlike many of the prior art methods and deinking or “ washing ” process .