• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    Embodiments of sized fluff pulp, or fluff pulp treated with a sizing agent, have desirable characteristics for one or more intended applications. The sized fluff pulp can be debonded or non-debonded. In several examples, the one or more desirable characteristics includes a reduction in its absorption characteristics (e.g., the pulp is less hydrophilic). Some characteristics improved by the sized fluff pulp include, but are not limited to, soak and drip capacity and wicking rate. In several examples, the sized fluff pulp are less hydrophilic but retain or exhibit other desirable characteristics for producing non-wovens, including low fiberization energy and fiberized knot percentage.
    公开号:SE1451552A1
    申请号:SE1451552
    申请日:2014-12-16
    公开日:2015-07-01
    发明作者:James H Wiley
    申请人:Weyerhaeuser Nr Co；
    IPC主号:
    专利说明:

    [1] [0001] Wood pulp fibers are valued for their low cost and ease of handling. Wood pulp fibers arealso compostable and renewable and can be grown on land typically not suitable for food crops.
    [2] [0002] Wood pulp fibers are produced by either mechanical pulping or chemical pulping. Wood,which is a composite structure in which mostly cellulosic fibers are held together with hemicellulose andlignin, is broken down during the pulping process so that individual fibers are obtained. Mechanicalpulping uses various types of grinding to accomplish this task and most of the hemicellulose and ligninare retained. Chemical pulping, on the other hand, uses chemicals to break the bonds holding thecomposite structure together and most of the lignin is dissolved and removed.
    [3] [0003] Pulps are generally characterized in the industry as paper-grade pulp or fluff pulps. Paper-grade pulps, derived from either hardwoods or softwoods, are used in the manufacture of paper, tissue,and packaging. Paper-grade pulps are typically sold in a heavy-weight sheet form similar to cardboard,with densities greater than 0.700 grams/centimeter3. The paper-grade pulp sheets are packaged asdiscontinuous sheets that are stacked up to form bales.
    [4] [0004] To make articles with paper-grade pulp, the baled paper-grade pulp is introduced into ahydropulper and a slurry is formed. ln the hydropulper, the paper-grade pulp fibers are redispersed inwater by aggressive mechanical agitation. Consequently, moisture content of paper-grade pulps istypically disregarded, and thus, the high costs associated with pulp drying are avoided. As a result,paper-grade pulps have a moisture content greater than 10% and in some cases as high as 20-25% ormore. Further, the high densities (greater than 0.700 g/cm3) of paper-grade pulp do not pose a problemas the aggressive mechanical agitation easily disperses the fibers into a slurry suitable for paper-making.
    [5] [0005] Fluff pulps are typically employed in the manufacture of non-wovens. Non-wovens arefibrous webs or fabrics in which the fibers are neither woven nor knitted. Non-wovens are typicallymade by dry-laying processes, such as airlaying, spunbonding, hydroentangling, etc. As such, and incontrast with paper-grade pulp, fluff pulp has a moisture content of 10% or less. Fluff pulps are typicallymade from long fibered softwoods, such as loblolly pine. Fluff pulps are dried in a continuous sheetform and wound onto rolls.
    [6] [0006] Currently available fluff pulp is quite hydrophilic, limiting the uses of fluff pulp toadsorbents, such as diapers, feminine hygiene products, incontinence products, etc. Since fluff pulp iseconomical, the pulp industry is constantly striving to produce new applications for fluff pulps.
    [7] [0007] This summary is provided to introduce a selection of concepts in a simplified form that arefurther described below in the Detailed Description. This summary is not intended to identify keyfeatures of the claimed subject matter, nor is it intended to be used as an aid in determining the scopeof the claimed subject matter.
    [8] [0008] ln accordance with aspects of the present disclosure, a fluff pulp sheet is provided. Thefluff pulp sheet comprises a composition that includes pulp fibers and a sizing agent. The compositionhas a soak and drip capacity of less than 15 grams/gram, and an air laid pad wicking rate of less than 3.0mm/s. The fluff pulp sheet in some embodiments has a density of less than 0.650 g/cm3 and a moisturecontent of less than 10%.
    [9] [0009] ln accordance with another aspect of the present disclosure, a fluff pulp sheet is provided.The fluff pulp sheet comprises a composition that includes wood pulp fibers, a debonding agent, and asizing agent, wherein the composition has a soak and drip capacity of less than 15 grams/gram, an airlaid pad wicking rate of less than 3.0 mm/s. The fluff pulp sheet is some embodiments has a moisturecontent of less than 10%, and a density of less than 0.650 g/cm3.
    [10] [0010] ln accordance with another aspect of the present disclosure, a fluff pulp sheet, comprisingfluff pulp fibers and a sizing agent. The fluff pulp sheet in some embodiments has a soak and dripcapacity of less than 15 grams/gram, an air laid pad wicking rate of less than 3.0 mm/s, a fiberizationenergy of less than 120 kJ/k, and a fiberized knot percentage of less than 30 percent.
    [11] [0011] The concepts, features, methods, and component configurations briefly described aboveare clarified with reference to the accompanying drawings and detailed description below.
    [12] [0012] The foregoing aspects and many of the attendant advantages of the claimed subjectmatter will become more readily appreciated as the same become better understood by reference tothe following detailed description, when taken in conjunction with the accompanying drawings,wherein:
    [13] [0013] FIGURE 1 illustrates a representative production process for a fluff pulp sheet inaccordance with aspects of the present disclosure; and
    [14] [0014] FIGURE 2 illustrates a representative post production process for adding a sizing agent to afluff pulp sheet in roll form in accordance with aspects of the present disclosure.
    [15] [0015] The detailed description set forth below in connection with the appended drawings,where like numerals reference like elements, is intended as a description of various embodiments of thedisclosed subject matter and is not intended to represent the only embodiments. Each embodimentdescribed in this disclosure is provided merely as an example or illustration and should not be construedas preferred or advantageous over other embodiments. The illustrative examples provided herein arenot intended to be exhaustive or to limit the claimed subject matter to the precise forms disclosed.Similarly, any steps described herein may be interchangeable with other steps, or combinations of steps,in order to achieve the same or substantially similar result.
    [16] [0016] The following discussion provides examples of fluff pulps treated with a sizing agent(hereinafter referred to as sized fluff pulp) in order to realize desirable characteristics for one or moreintended applications. Several examples set forth in the present disclosure may include debonded ornon-debonded, sized fluff pulps, sized Kraft fluff pulps, etc., that include one or more desirablecharacteristics, including a reduction in its absorption characteristics (e.g., less hydrophilic). As will bedescribed in more detail below, some characteristics improved by the fluff pulp of the present disclosureinclude but are not limited to soak and drip capacity and wicking rate. As will be further described inmore detail below, examples of the sized fluff pulp are less hydrophilic but retain or exhibit otherdesirable characteristics for producing non-wovens, including low fiberization energy and fiberized knotpercentage.
    [17] [0017] "Fiberization Energy" as used herein means the amount of energy in kilo Joules requiredto fiberize one kilogram of pulp in dry sheet form. Fiberization is the process of breaking apart a drypulp sheet into individualized fibers. The section entitled "Test Methods" provides a test procedure inwhich a hammermill, commercially available from Kamas Laboratory, is used to measure fiberizationenergy as the pulp sheets are fiberized.
    [18] [0018] "Knots" are fiber bundles and pieces of the pulp sheet that have not fully broken apartduring the fiberization process. Knots are defined herein as the fraction of the fiberized fluff that isretained on an ASTM 12 mesh screen. "Knot percentage" or "Fiberized Knot percentage" as used hereinmeans the percentage of knots (vs. accepts). The section entitled "Test Methods" provides a testprocedure for measuring the weight fractions of accepts, knots and fines in a fiberized fluff sample.[0019] "Soak and drip capacity" as used herein means the weight of test liquid retained by afiberized fluff pulp specimen after the specimen has been submerged in the test liquid for 30 minutesand then allowed to drip for three (3) minutes. The soak and drip capacity is expressed as the weight ofliquid absorbed to the original weight of the test specimen. The section entitled "Test Methods"provides a test procedure for measuring soak and drip capacity.
    [20] [0020] "Air laid pad wicking rate" as used herein means the rate, in millimeters/second, that atest fluid will wick through an air|aid pad containing four (4) grams of f|uff under load of 2.5 kilopascals.The section entitled "Test Methods" provides a test procedure for measuring wicking rate in air|aid pads.[0021] One intended application for the sized f|uff pulps of the present disclosure includes but isnot limited to non-woven disposable wipes, including wipes to which a saturant, such as a surfactant, isapplied. Disposable wipes are usually manufactured from non-wovens containing conventional f|uffpulp and a quantity of saturant. To be effective, a selected amount of saturant is needed at the surfaceof the wipes so that, when the wipe is used, the saturant will transfer to the surface being cleaned (e.g.,hands, countertops, etc.). ln disposable wipes manufactured with conventional f|uff pulp, a hydrophilicmaterial, a larger quantity of saturant than is transferred during use is required, due to thehydrophilicity of the pulp retaining some saturant in the wipe. Contrastingly, a sized f|uff pulp (i.e., onethat is less hydrophilic than conventional f|uff pulps), according to aspects of the present disclosure, isbeneficial for use in the manufacture of disposable wet wipes in that it reduces the amount of saturantadded in the manufacturing process because less saturant will be retained by the f|uff pulp when thewipe is used. This may result in lowered costs due to decreased saturant cost, less shipping cost, and soforth.
    [22] [0022] Other intended applications may benefit from a sized f|uff pulp having a reduction in itsabsorption characteristics, such as wet wipes for absorbing oil and other oleophilic substances, diaperliners, paper towels, among others.
    [23] [0023] ln certain embodiments, the pulp used to form the pulp sheets of the present disclosureincludes cellulose pulp or wood pulp. "Cellulose pulp" or "wood pulp" as used herein refers to theproduct resulting from the wood pulping process. The pulping process can be either mechanical,chemical, or both (e.g., hybrid processes such as chemithermomechanical pulping (CTMP)). The pulpedfibers can be bleached or non-bleached. ln some embodiments, the chemical process known as "kraftpulping" is employed, although other chemical pulp processing, such as sulfite processing, can beemployed. Kraft and sulfite pulping processes are known to those of skill in the art and will not bediscussed in detail herein.
    [24] [0024] The fluff pulping raw materials in some embodiments are sources of cellulose,hemicellulose and lignin and the terms "wood" or "tree" is used herein to generically describe anysource of cellulose, hemicellulose and lignin. ln the wood pulping industry, trees are conventionallyclassified as either hardwood or softwood. Examples of softwood species from which fluff pulp isformed include, but are not limited to: fir such as Douglas fir and Balsam fir, pine such as Eastern whitepine and Loblolly pine, spruce such as White spruce, larch such as Eastern or Siberian larch, cedar, andhemlock such as Eastern and Western hemlock. ln certain embodiments, the fluff pulp is a southernbleached softwood kraft (SBSK) pulp. Alternatively, fluff pulps in some embodiments of the presentdisclosure may also utilize hardwoods as the source of wood for the pulp, or a combination of softwoodand hardwoods.
    [25] [0025] While the various aspects of the present disclosure are presented in terms of examplesrelated to pulp derived from wood, it will be appreciated that the disclosed examples are illustrative innature, and therefore, should not be construed as limited to wood pulp applications. lt should thereforebe apparent that these various aspects of the present disclosure have wide application, and can beemployed with pulp derived from any source, such as fiber crops, etc.
    [26] [0026] As will be described in more detail below, in some embodiments, during the fluff pulpmanufacturing process, debonders or debonding agents may be used. Debonders are surface activechemicals that are added prior to, or during, the forming and drying operation of the fluff pulpmanufacturing process. The purpose of debonders is to reduce the amount of fiber-fiber bonding thattakes place during drying. Examples of debonding agents are Evonik Arosurf® PA 777 and PA 780, EkaSoftTM F509 HA, F587 and F639. The fluff pulps of the present disclosure can be treated with otherdebonders as well.
    [27] [0027] As will be fully described in more detail below, during the fluff pulp sheeting process,sizing agents may be used. Sizing agents are chemicals that are added prior to, during, or after the sheetforming process. The purpose of the sizing agent is to increase water resistance of the fiber or fibers.Generally speaking, sizing agents are amphiphilic molecules, having both hydrophilic (water-loving) andhydrophobic (water-repelling) ends. The sizing agent adheres to substrate fibers and tends to form afilm, with the hydrophilic tail facing the fiber and the hydrophobic tail facing outwards, imparting asmooth finish that tends to be water-repellent. Examples of sizing agents include alkyl succinicanhydrides (ASAs), alkyl ketene dimers (AKDs), polysiloxanes, rosin, starches, gums, and so forth. Thefluff pulps of the present disclosure can be treated with other sizing agents as well.
    [28] [0028] The sized fluff pulp sheets of the present disclosure can be employed in the manufactureof non-woven articles, such as disposable wipes, paper towels, etc. ln that regard, the sized fluff pulpsheets are fiberized in order to obtain individual fluff pulp fibers. Next, the individual fluff pulp fibersare used to manufacture the non-woven article via dry-laying processes, such as airlaying, spunbonding,hydroentangling, etc. ln some embodiments, the fluff pulp fibers are mixed with non-fluff pulp fibersprior to the dry-laying process. For example, synthetic fibers, such as polypropylene, polyester, etc., canbe mixed with the fluff pulp fibers. Other fibers may be additionally or alternatively included, such asnatural fibers, including cotton, etc. The additional non-fluff pulp fibers can be employed to obtaindesired characteristics, or to enhance the characteristics obtained from the sized fluff pulp fibers. Theamount of added non-fluff pulp fibers can be, for example, from 2% to 20% by weight or greater.
    [29] [0029] ln the following description, numerous specific details are set forth in order to provide athorough understanding of one or more embodiments of the present disclosure. lt will be apparent toone skilled in the art, however, that many embodiments of the present disclosure may be practicedwithout some or all of the specific details. ln some instances, some process steps are not described indetail in order to not unnecessarily obscure various aspects of the present disclosure. Further, it will beappreciated that embodiments of the present disclosure may employ any combination of featuresdescribed herein.
    [30] [0030] FIGURE 1 illustrates in block diagrammatic form, one representative process 100 forforming fluff pulp sheets in accordance with aspects of the present disclosure. Process 100 includespulping 102, pulp sheet forming 104, pressing 108, and one or more stages of drying 112. The processmay also include reeling 116, in which the fluff pulp sheet is wound into roll form. The forming of fluffpulp sheets begins with pulping 102, in which pulp raw materials, such as wood, fiber crops, etc., arepulped in a chemical pulping process. The chemical pulping process can be any conventional pulpingprocess that arrives at fluff pulp fibers, such as Kraft pulping, sulfite pulping, etc. The slurry of pulpedfibers can then be optionally bleached with chlorine or chlorine-free compounds, for example.
    [31] [0031] The fluff pulp, typically in a slurry, resulting from pulping 100 is then poured onto amoving screen at pulp sheet forming 104 in order to form a fluff pulp sheet. As the fluff pulp slurrytravels on the moving screen, one or more processes may occur to remove moisture from the fluff pulpslurry. For example, a mechanical press can be used to force liquid out of the fluff pulp at pressing 108,and/or heat, air flow, etc., can be employed at drying 112, to remove liquid from the fluff pulp. Drying112 can be carried out in one or more stages, including a first stage of drying 112A and a second stage ofdrying 112B. The fluff pulp sheet may then be rolled into roll form at reeling 116. ln someembodiments, the fluff pulp sheet prior to roll form has a moisture content of 10% or less, and in someembodiments between 6% and 10%, and has a pulp density of less than 0.650 g/cm3, and in someembodiments between about 0.500 g/cm3 and 0.610 g/cm3.
    [32] [0032] ln embodiments in accordance with the present disclosure, a sizing agent is added to thefluff pulp. ln some embodiments, one or more sizing agents can be added to the fluff pulp during thefluff pulp sheet forming process. For example, in some embodiments, the one or more sizing agents canbe added before pulp sheet forming 104 when the fluff pulp is in a slurry, after pressing 108, when fluidfrom the pulping process is pressed out of the fluff pulp, and/or after the first and/or second stages ofdrying 112A, 112B, where additional moisture is removed from the fluff pulp. When adding the sizingagent before pulp sheet forming 104, the sizing agent may be in a dispersed or emulsified form. Whenadding the sizing agent to the fluff pulp sheet after pressing and/or drying, techniques including but notlimited to spraying, showering, and/or dipping techniques may be employed. ln some of theseembodiments, the sizing agent may be in a melted or neat form.
    [33] [0033] ln accordance with aspects of the present disclosure, a sizing agent may be additionally oralternatively added to post processed fluff pulp (e.g., after the fluff pulp sheets are reeled into roll). lnthese embodiments, the rolled fluff sheet can be unwound at a pulp roll unwind stand, treated with asizing agent via spray, shower, and/or dipping techniques, and then rerolled into roll form by a rewinder,as shown in the process 200 of FIGURE 2. Optional processes may be carried out after the sizing agent isadded. For example, the sized fluff pulp sheet can be dried with an optional dryer or cured at an optioncuring station.
    [34] [0034] lt will be appreciated that in embodiments of the present disclosure the sizing agent isgenerally non-uniform in its interaction with and/or coverage on the composition of fibers of the sizedfluff pulp sheet. As such, the sized fluff pulp sheets may include fibers, or portions thereof, with andwithout a sizing agent adhered or otherwise coupled thereto. Similarly, certain sections of the sized fluffpulp sheets may include fibers, or portions thereof, with and without a sizing agent adhered orotherwise coupled thereto.
    [35] [0035] As a result of the addition of a sizing agent to fluff pulp in accordance with embodimentsof the present disclosure, a composition of sized fluff pulp fibers, and/or a sized fluff pulp sheet, orsections thereof, may be produced with one or more of the following characteristics: a soak and dripcapacity of less than 15 grams/gram; an air laid pad wicking rate of less than 3.0 mm/s; a fiberizationenergy of less than 120 kJ/kg, and less than 80 kJ/kg in some embodiments; a fiberized knot percentageof less than 30 percent, and less than 5% in some embodiments; and any combination thereof.
    [36] [0036] Test Methods
    [37] [0037] ln the non-limiting examples that follow, the following test methods were employed todetermine various reported characteristics and properties of the fluff pulp sheets. ASTM refers to theAmerican Society of Testing Materials.
    [38] [0038] Fiberization energy testing is used to measure the amount of energy required to fiberizethe fluff pulp sheet during the fiberization process. Fiberization energy can be measured by fiberizing afluff pulp sheet using a laboratory hammermill, such as one available from Kamas Laboratory. Onemodel suitable for testing is model number 91883422, type KVARN K.0l. This type of hammermillprovides the ability to measure power consumption during the fiberization process, which can bedisplayed as a readout on an associated control panel. For testing the fluff pulp sheet samples describedbelow, the hammermill was equipped with a screen having 19 millimeter (mm) round holes. Duringtesting, the breaker bar gap was adjusted to 2.6 mm, the rotor speed was 3300 revolutions per minute(rpm) and the pulp feed rate was 2.8 grams/second (g/s). A vacuum cleaner was used to provide airflow through the hammermill and draw the fiberized fluff through the screen. The air flow from thevacuum cleaner was 1500-2000 cubic feet per minute (CFM).
    [39] [0039] Fluff pulp sheet samples to be tested were cut into 2 inch wide by 18 inch long strips. Thestrips were conditioned at 50% relative humidity (RH) and 70° F (21.1° C) for at least four (4) hours prior11to measurement. The room where the test hammermill was located was also conditioned to 50% RH.The energy requirement values reported are an average of 10 individual readings.
    [40] [0040] Knot percentage testing is used to measure the percentage of knots. Fluff generated bythe test hammermill during the fiberization process described above was tested for knots content with aDefiberization Efficiency (DE) test apparatus manufactured by Courtray Consulting Labservice, 2 rueCharles, MONSARRAT, 59500 Douai France. This device uses a series of standard ASTM mesh screens toseparate fluff into knots and accepts. ln this test procedure, knots are the fraction that is retained on anASTM 12 mesh screen.
    [41] [0041] Soak and drip capacity testing is used to measure the liquid absorption and retentioncharacteristics of the fluff pulp. ln the soak and drip capacity test, a sample of fiberized fluff was sealedinside a heat sealable teabag and submerged in a 0.9% saline solution for 30 minutes. After the 30minute saturation time, the bags were allowed to drip for three (3) minutes. The capacities werecalculated by measuring the amount of fluid remaining in fluff after the drip period, dividing by theweight of the original fluff.
    [42] [0042] The fiberized fluff for the soak and drip capacity test can be fiberized by the testhammermill as described above, or by a blender according to the following procedure. The fiberizedfluff generated by either procedure can be used in wicking rate or soak and drip capacity tests.
    [43] [0043] Samples of fluff pulp sheets where conditioned at 50% RH and 70° F (2l.l° C) for four (4)hours prior to fiberization. The fluff pulp sheets to be fiberized were torn into small pieces(approximately 0.5g each). About 1.5 g of the pulp sheet pieces where weighed, and then placed in theblender, such as a Waring Blendor, model 3lBL92l (7011). To fiberize the pieces of fluff pulp, theblender is started under the high setting and run for 30 seconds, a duration adequate to achievecomplete fiberization of 1.5 g pulp sample. Running the blender for longer times will increase the risk offiber damage and fines generation.
    [44] [0044]follows.
    [45] [0045]
    [46] [0046]The teabags are prepared as follows.12The materials, procedure, and calculations to determine soak and drip capacity were asTest equipment:teabag paper 3 inches (75 mm) wide, heat-sealable, or presealed material 60 x 85 mm,examples of which are commercially available from Ahlstrom Fiber Composites Division,Edinburgh, Scotland;screen Teflon®-coated, 0.25-inch (6-mm) mesh, available from Eagle Supply and Plastic,Inc., part # 7308 or equivalent;a heat sealer, such as Clamco Model 450 or equivalent;a swelling container - polyethylene, approximately 400 x 250 x 50mm;testing fluid: 0.9% (w/w) aqueous isotonic saline;a paper cutter; a balance; a timer; a paper toweling; and a writing instrument, such as apen.
    [47] [0047]Once the teabags were prepared, the following procedure was carried out in order to testthe soak and drip capacity of the fluff pulp:Weigh empty labeled teabag to the nearest 0.001 gram (g) and record (Wt 0);Using a balance, measure out 0.200 i- 0.005 g of fiberized fluff to be tested;Transfer into teabag and heat seal the open edge;Weigh the fluff-filled specimen teabag to the nearest 0.001 gram and record (Wt 1);Repeat steps 1-4 for all specimens;10.11.12.
    [48] [0048]
    [49] [0049]13Weight two (2) empty or "blank" teabags to the nearest 0.001 gram, and record.Calculate average weight of the blanks (Wb 0);Fill container with ” 1.5" of testing fluid;Place the fluff-filled specimen teabags as well as the two (2) blank teabags on one drypiece of mesh screen. The teabags should not be touching. For the fluff-filled specimenteabags, make sure that the fibers are evenly distributed in the center of the bag andaway from the seals.
    [50] [0050] Example 1: Laboratory Sizing Study - Wicking Rate, Fiberization Energy and Knots[0051] The following experiment was carried out to compare the effects of three (3) differentsizing agents on wicking rate, fiberization energy and knots percentage of a debonded fluff pulp. Thesizing agents were applied on commercially available fluff pulp sheets. After the application of the sizingagents, the treated sheets were aged for two weeks either at room temperature or in an oven at 38” C(100.4° F).
    [52] [0052] CF405 fluff pulp, manufactured by Weyerhaeuser NR in Columbus MS, was used in thisexperiment. CF405 fluff pulp is a bleached kraft southern pine fluff pulp containing a debonding agent.Three sizing agents were added to the CF405 fluff pulp: Aquapel 650; Hercon 100; and Hercules 5218, allavailable from Ashland Inc. Each of these sizing agents is an AKD-water emulsion having approximately15% solids.
    [53] [0053] All sizing agents were applied at 0.25% level (0.25 g of sizing agent per 100 grams pulp(dry solids basis)). The sizing agents were applied by drawing the desired weight of sizing agent solutioninto a syringe and then applying the sizing agent onto the pulp sheet in evenly space lines roughly 1/4-1/2 inch apart. The treated pulp sheets were wrapped in foil and aged two (2) weeks either at ambientroom temperature or in a forced air lab oven held at 38” C (100.4° F). Pulp sheet samples without sizingtreatment (i.e., control samples) were also wrapped in foil and aged under the same conditions as thesized samples.
    [54] [0054] The pulp sheet samples to be oven aged after treatment were preheated in a 60°C(140° F)oven for at least two (2) hours prior to the application of the sizing agent. The control samples werealso preheated. The moisture content of these preheated samples was 2.3% prior to the application ofthe sizing agent. The sizing agents were diluted to 2.78% solids prior to application so that the moisturecontent of the treated sheets was 9.99%.
    [55] [0055] The pulp sheet samples to be aged at room temperature were not preheated. Themoisture content of these samples prior to sizing application was 5.9%. The sizing agents were dilutedto 4.9% solids prior to treating these samples so that the final moisture content of the treated pulpssamples was 9.99%.
    [56] [0056] After the samples had been aged for two (2) weeks, the samples were conditionedovernight at 50% RH and 70° F (21.1° C) prior to testing. The samples were then tested to determinefiberization energy, knots percentage, and wicking rate in accordance with the testing proceduresdescribed above. The results are summarized in Table 1 below. The results demonstrate that it ispossible to obtain a fluff pulp with very low wicking rates while retaining beneficial fiberization energyand knots percentage levels.
    [57] [0057] Example 2: Laboratory Sizing Study - Wicking Rate, Fiberization Energy, Soak and DripCapacity, and Knots Percentage
    [58] [0058] The following experiment was carried out to compare the effects of one (1) sizing agenton wicking rate, fiberization energy, soak and drip capacity and knots percentage of a non-debondedfluff pulp. ln this experiment, a sizing agent (Aquapel 650) was applied to CF416 fluff pulp at twodifferent application levels, 0.5 grams of sizing agent solids per 100 grams of dry fibers, and 0.75 gramsof sizing agent solid per 100 grams of dry fibers. After the application of the sizing agents, the treatedsheets were aged in a laboratory oven held at 60 C (140° F) for approximately 20 hours. After the 20hours of aging time, the pulp sheets were allowed to stand at 50% RH and room temperature for at least4 hours before testing.
    [59] [0059] CF416 is a fluff pulp manufactured by Weyerhaeuser NR in Columbus, MS. lt is madewithout a debonding agent. Aquapel 650 is an AKD-water emulsion sizing agent manufactured byAshland Inc. Prior to use, the sizing agent was diluted from the as-received solids level of 15% to 10% inorder to facilitate more uniform application.
    [60] [0060] The sizing agent was applied on the pulp sheet by drawing the desired weight of the sizingsolution into a syringe and then expressing the sizing agent onto the pulp sheet in evenly spaced linesone quarter to one half an inch apart. After the sizing agent was applied, the treated sheets wereplaced directly in a lab oven for aging. An untreated control was also prepared which contained nosizing agent and was stored at room temperature rather than being placed in the oven.
    [61] [0061] The samples were then tested to determine fiberization energy, knots percentage, soakand drip capacity and wicking rate in accordance with the testing procedures described above. Theresults are summarized in Table 2 below. The results demonstrate that it is possible to obtain a fluff17pulp from a non-debonded fluff pulp with very low wicking rates and soak and drip capacities whileretaining beneficial fiberization energy and knots percentage levels.
    [62] [0062] Example 3: Laboratory Sizing Study - Soak and Drip Capacity[0063] ln this experiment, a sizing agent (Aquapel 650) was applied to CF405 fluff pulp at twodifferent addition levels, 0.25% (0.25 grams of sizing agent solids per 100 grams of dry fiber) and 0.50%(0.5 grams of sizing agent solids per 100 grams of dry fiber). The sizing agent in this experiment wasapplied in the same manner as described above in Example 1, except that the sizing agent was appliedas received without dilution and the pulp sheets were all at ambient temperature when the sizing agentwas applied.
    [64] [0064] After the sizing agent was applied, the fluff pulp sheets were wrapped in foil and aged in aforced air lab oven at 60° C (140° F) for four (4) hours. A sample of untreated CF405 was also oven-agedin the same manner to serve as a control. After four (4) hours of aging, the samples were removed fromthe oven and fiberized in a blender according to the test procedures described above. Soak and dripcapacity tests were performed on the fiberized fluff samples according to test methods as describedabove. Results of these tests are summarized in Table 3. These results show that it is possible toproduce a fluff pulp having very low soak and drip capacity.18Sizing Agent Application Level % Soak and Drip Capacity (g/g)0 (control) 22.60.25 5.40.50 <0.5Table 3[0065] Example 4: Roll Application Study[0066] ln this experiment, a sizing treatment process set forth in FIGURE 2 was carried out. lnthat regard, a small roll of CF405 fluff pulp was mounted on an unwind stand and threaded onto arewinder. A shower bar was mounted over the fluff pulp sheet. A pump was used to pump sizingsolution out of a vat through the shower bar and onto the fluff pulp sheet as it was being wound fromthe unwind stand onto the rewind spool. The shower bar had a row of nozzles spaced 1/4 inch apartacross the width of the fluff pulp sheet. The diameter of the nozzle orifices was 30 thousandths of aninch. The sizing solution employed Aquapel 650 as the sizing agent, and had a solids level of the 16%.
    [67] [0067] After the fluff pulp roll had been treated, it was wrapped with plastic film stretch wrapand stored prior to testing. After two (2) weeks, a sample was removed for fiberization energy testingand knots percentage testing according to the test methods described above. The results aresummarized in Table 4.
    [69] [0069] The results show that a small reduction in soak and drip capacity occurred after the pulphad been aged 10 weeks at ambient temperature, and further capacity reduction could be broughtabout through heat treatment.
    Sizing Treatment Oven Aging Time Oven Aging Temperature ågïlššïålšklgl;0 (control) 4 hours 60° C (140° F) 22.60.7% 30 seconds 93° C(199.4° F) 16.10.7% 2 minutes 93° C(199.4° F) 15.40.7% 30 seconds 177° C (350.6° F) 7.60.7% 2 minutes 177° C (350.6° F) 6.6Table 5[0070] The principles, representative embodiments, and modes of operation of the presentdisclosure have been described in the foregoing description. However, aspects of the present disclosurewhich are intended to be protected are not to be construed as limited to the particular embodimentsdisclosed. Further, the embodiments described herein are to be regarded as illustrative rather thanrestrictive. lt will be appreciated that variations and changes may be made by others, and equivalentsemployed, without departing from the spirit of the present disclosure. Accordingly, it is expresslyintended that all such variations, changes, and equivalents fall within the spirit and scope of the presentdisclosure, as claimed.
    权利要求:
    Claims (20)
    [1] l. A fluff pulp sheet, comprising: a composition including pulp fibers and a sizing agent, the composition having a soak and dripcapacity of less than 15 grams/gram, and an air laid pad wicking rate of less than 3.0 mm/s; wherein the fluff pulp sheet has a density of less than 0.650 g/cm3 and a moisture content of less than 10%.
    [2] 2. The fluff pulp sheet of claim l, wherein the composition also has a fiberized knot percentage of less than 30%.
    [3] 3. The fluff pulp sheet of claim 2, wherein the composition also has a fiberization energy of less than 120 kJ/kg.
    [4] 4. The fluff pulp sheet of claim l, wherein the composition also has a fiberization energy of less than 120 kJ/kg.
    [5] 5. The fluff pulp sheet of claim l, wherein the composition also has a fiberized knot percentage of less than 5% and a fiberization energy of less than 80 kJ/kg. 21
    [6] 6. The fluff pulp sheet of claim 1, wherein the composition further includes a debondingagent
    [7] 7. The fluff pulp sheet of claim 1, wherein the sizing agent includes one or more AKD-wateremulsions.
    [8] 8. A non-woven article made from the fluff pulp sheet of claim 1.
    [9] 9. A non-woven article made from the fluff pulp sheet of claim 1 and fibers selected from a group consisting of synthetic fibers and natural fibers pulp fibers, and combinations thereof.
    [10] 10. A fluff pulp sheet, comprising: a composition including wood pulp fibers, a debonding agent, and a sizing agent, wherein thecomposition has a soak and drip capacity of less than 15 grams/gram and an air laid pad wicking rate ofless than 3.0 mm/s; wherein the fluff pulp sheet has a moisture content of less than 10%, and a density of less than 0.650 g/cm3.
    [11] 11. The fluff pulp sheet of claim 10, wherein the composition also has a fiberized knot percentage of less than 30%.
    [12] 12. The fluff pulp sheet of claim 11, wherein the composition also has a fiberization energy of less than 120 kJ/kg. 22
    [13] 13. The fluff pulp sheet of claim 10, wherein the composition also has a fiberization energy of less than 120 kJ/kg.
    [14] 14. The fluff pulp sheet of claim 10, wherein the composition also has a fiberized knot percentage of less than 5% and a fiberization energy of less than 80 kJ/kg.
    [15] 15. A fluff pulp sheet, comprising: fluff pulp fibers; and a sizing agent; wherein the fluff pulp sheet has a soak and drip capacity of less than 15 grams/gram, an air laidpad wicking rate of less than 3.0 mm/s, a fiberization energy of less than 120 kJ/kg, and a fiberized knot percentage of less than 30 percent.
    [16] 16. The fluff pulp sheet of claim 15, wherein fluff pulp sheet has a fiberization energy of less than 80 kJ/k.
    [17] 17. The fluff pulp sheet of claim 15, wherein fluff pulp sheet a fiberized knot percentage of less than 5%.
    [18] 18. The fluff pulp sheet of claim 15, wherein the fluff pulp sheet has a moisture content of between 6% and 10%, and a density of between 0.500 g/cm3 and 0.610 g/cm3.
    [19] 19. The fluff pulp sheet of claim 15, wherein the sizing agent includes one or more AKD- water emulsions.
    [20] 20. The fluff pulp sheet of claim 15, further including a debonding agent.
    类似技术:
    公开号 | 公开日 | 专利标题
    CA2649304C|2011-11-22|Treated cellulosic fibers and absorbent articles made from them
    FI63073C|1983-04-11|FLUFFMASSA OCH SAETT FOER FRAMSTAELLNING DAERAV
    CN104947509B|2017-11-03|Dry fluff pulp sheet additive
    US11041272B2|2021-06-22|Fluff pulp and high SAP loaded core
    KR20010100017A|2001-11-09|Steam Explosion Treatment with Addition of Chemicals
    US20030172464A1|2003-09-18|Liquid ammonia explosion treatment of wood fibers
    EP1457184A1|2004-09-15|Saccharide treated cellulose pulp sheets
    RU2399708C2|2010-09-20|Method of preparing mercerised fibre
    US20070107862A1|2007-05-17|Sodium sulfate treated pulp
    US20140041818A1|2014-02-13|Fluff pulp and high sap loaded core
    US8801901B1|2014-08-12|Sized fluff pulp
    US20050019563A1|2005-01-27|Glyoxal crosslinked cellulosic fibers having high bulk
    CN113412104A|2021-09-17|Improved absorption properties by cross-linking cellulose with glyoxal
    EP2206523B1|2012-07-18|Treated cellulosic fibers and absorbent articles made from them
    US20050016699A1|2005-01-27|Glyoxal crosslinked cellulosic fibers having high bulk
    US20200308766A1|2020-10-01|Treated pulp and methods of making and using same
    SE1951006A1|2021-03-05|Fluff pulp from oxygen delignified pulp
    AU2020340608A1|2022-03-10|Fluff pulp
    同族专利:
    公开号 | 公开日
    BR102014029860A2|2015-09-15|
    SE540039C2|2018-03-06|
    US8801901B1|2014-08-12|
    CL2014003366A1|2015-10-23|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US3212961A|1961-10-23|1965-10-19|Hercules Powder Co Ltd|Pretreatment of paper pulp with ketene dimer in improving sizeability|
    US3901238A|1974-03-18|1975-08-26|Procter & Gamble|Disposable diaper having a resin treated absorbent pad to improve integrity, softness and dryness|
    US5071675A|1989-03-20|1991-12-10|Weyerhaeuser Company|Method of applying liquid sizing of alkyl ketene dimer in ethanol to cellulose fibers entrained in a gas stream|
    US5163931A|1991-01-02|1992-11-17|Pablo Aldrett|Substantially hydrophobic and biodegradable laminar cellulose material, its manufacturing method, and substantially biodegradable disposable diapers made of said material|
    US5938894A|1996-03-25|1999-08-17|Eka Chemicals Ab|Absorbent cellulosic material and production thereof|
    JP5089009B2|2000-10-04|2012-12-05|ジェイムズハーディーテクノロジーリミテッド|Fiber cement composites using sized cellulose fibers|
    US6607636B2|2001-11-01|2003-08-19|Kimberly-Clark Worldwide, Inc.|Non-rewetting multi-fiber hand towel and methods of making same|
    AT512144B1|2011-11-08|2013-12-15|Chemiefaser Lenzing Ag|Man-made collulose fibers with hydrophobic properties|
    AT512143B1|2011-11-08|2013-12-15|Chemiefaser Lenzing Ag|Cellulose fibers with hydrophobic properties and high softness and the associated manufacturing process|
    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    US14/144,243|US8801901B1|2013-12-30|2013-12-30|Sized fluff pulp|
    [返回顶部]