Forest Sciences Commons^™

The Effect Of Drying Conditions On The Surface Strength Of Clay Coated Paper, Lawrence A. Gaspar

Paper Engineering Senior Theses

The importance of the continuous-film forming properties of the polymer via fusion upon heating is second to none. Yasuda states that it depends on the probability of two particles coalescing upon the application of heat versus the acceleration of the rate of removal of the disperse medium from the coating. Naturally it would seem that excessive rates of drying would not permit the adhesive to fuse, but it may also alter the distribution of adhesive throughout the coating in either case. Eames has suggested the effects of certain variables on the distribution of starch in starch-clay coatings, but the fact …

Two Stage Peroxide-Borohydride Bleaching Of Cold Soda Pulp, Valerie A. S. Estes

Paper Engineering Senior Theses

Survey of Literature

Introduction

Since the development of cold soda pulping in the early 1950's, the search for suitable bleaching methods has been of primary concern. Cold soda pulp is dark brown in color and resists the bleaching action of most chemicals. Marton (1) suggests that this brown discoloration of hardwood cold soda pulp is due to a material in the cells of the wood, primarily in the heartwood. These substances, which have not been identified, are not the same as lignin but probably develop in a similar manner.

The chemicals most often used in bleaching hardwood cold soda pulps …

Effect Of Pulping Time On The Chemical Composition Of Cold Soda Pulp, Timothy K. Estes

Paper Engineering Senior Theses

Literature Survey

Introduction

The cold soda pulping process was developed by the Forest Products Laboratory, Madison, Wisconsin, around 1950. It is a high yield process in which wood chips are softened by reacting with sodium hydroxide and then defiberized by mechanical refining. The yield is usually between 80%-95%.

Cold soda pulps with the following characteristics were used for this literature survey: The yields were between 80%-95%. The pulping temperatures were less than 40°C. The pulping operations were conducted under atmospheric pressure.

An Investigation Of The Influence Of Shearing Forces On Pulp Strength, Ronald O. Luedeke

Paper Engineering Senior Theses

This thesis attempts to determine the importance of shearing forces in the strength development of a pulp.

Theoretically, if these shearing forces are able to flex the fibers and thereby reduce their stiffness, it follows that more intimate fiber to fiber contact will result with a related higher bonded area and consequent increased paper strength.

The pulp was subjected to the shearing forces in a Day sigma blade kneader at a high consistency. The treatment time was increased in sequence in an attempt to obtain the maximum strength development these shearing forces could produce.

The work certainly demonstrated that shearing …

The Effect Of Structure On The Stiffness Of Cylinder Board, Nelson D. Woodruff

Paper Engineering Senior Theses

The purpose of this thesis was to study the effect of board structure on the stiffness of cylinder board. This area was chosen as stiffness is one of the most important attributes of cylinder board and the literature survey revealed that very little work has been done in this area.

A new method for making multi-ply boards in the laboratory was developed. These boards were made in the British Sheet Machine under constant head and avoided the problems associated with wet-pressing individual plies together. This method was found to give reproduceable results.

At certain compositions, multi-ply boards made with kraft …

The Rate Of Weakening Of Paper Due To An Applied Stress, Emmett F. Finley

Paper Engineering Senior Theses

Introduction

When a load is applied to a sheet of paper, the paper may break immediately or it may support the load for some period of time. It is recognized that the paper, while under a stress less than that required to cause immediate break, is weakened until it is finally unable to support the stress. Since in the normal use of paper the stress to which paper is subjected is less than that needed to cause immediate break this weakening is an important factor in many cases.

A few examples of such cases are the winding of the paper …

"A Study Of A Method To Predict Printing Quality Of Paper By Means Of Smoothness And Elongation Test Results", William R. Castle

Paper Engineering Senior Theses

The object of this thesis is to investigate the use of smoothness and elongation test results as criterion for evaluating the printing quality of paper. The relationship of smoothness and printing quality has been known for many years and in all previous work it has been shown to be influential to printing quality. The relationship of elongation and printing quality has never been investigated. The experimental procedure consisted of testing the paper samples for smoothness and elongation, and determining the printing quality of the different papers with the I. G. T. Printability Tester. The results of the analysis of the …

Some Experiments On The Utilization Of Rice Straw In Papermaking, Kirit C. Mody

Paper Engineering Senior Theses

I. A Brief Description of Rice Straw

The botanical name for rice straw is Oryza sativa. Rice is a well-known cereal and is the staple food of hundreds of millions of people. According to R. J. Rochevica, cultivated rice, including all numerous varieties, originated from will species, which are indigenous to Africa, India, and Indo-China (6).

Pigment Coating Of Paper In The Laboratory A Comparison Of Several Methods, Clare L. Longton

Paper Engineering Senior Theses

Four Bench-type laboratory coaters were compared as to their pattern formation which influences the printability of the coated sheet.

The four Bench-type laboratory coaters used were Wire Wound Doctor Rods, Bird Film Applicators, Bench Trailing Blade Coater and the Martinson Coater.

A constant solids content coating color was used which consisted of 100 parts coating clay and 18 parts casein. A record of the viscosity of the coating slip was kept.

The coated sheets were evaluated by visual inspection, and photomicrographs were taken of the most characteristic patterns. Coat weight, reproducibility and smoothness values were also determined.

It was found …

The Effect Of Chlorine, Hypochlorite, And Chlorine Dioxide Bleaching On The Hemicellulose Content Of Pulp, C. Wesley Smith

Paper Engineering Senior Theses

Until the recent time hemicelluloses were regarded as an undesirable part of the cellulose fiber; the most desirable fiber for paper-making purposes was believed to be one containing 100% pure cellulose. This theory is fallacious, since it is now known that hemicellulose plays a major role in paper-making and in fact, a satisfactory paper cannot be formed from wood pulp without some hemicellulosic material being present. The best pulp is one which has been cooked to remove most of the lignin, but not so drastically cooked as to degrade the cellulose or remove too much of the hemicellulose fraction. Such …

Deinking Of Coated Magazine Papers: Experiments With Some Enzymes, Edgar E. Moore Jr.

Paper Engineering Senior Theses

Introduction

At the present time fairly harsh procedures are used to deink magazine waste paper. The paper must be cooked in the presence of strong chemicals such as sodium hydroxide at elevated temperature and in some cases this is even carried out under pressure. This results in the removal of ink but the fibers are considerably darkened due to this procedure (1,2). It was the object of this survey to explore the literature to see if there is any information on a relatively mild method involving enzymes, which due to the absence of harsh chemicals and high temperatures would possibly …

Rheology Of Coating Adhesives, Ryan A. Smith

Paper Engineering Senior Theses

Many compounds, “flow modifiers”, have been used to change the flow properties of coating adhesives. Thiourea, ammonium thiocyanate, and urea were used in the work to find out what effect they would have on the coating adhesives, starch and alpha protein. It was found that they all lowered the viscosity a great deal. Also it was found that the resulting flow curve in most cases pseudoplastic.

A Laboratory Study Of The Effect Of Wet Pressing And Pulp Freeness On The Hygroexpansivity Of Sulphite Paper, Robert L. Woodall

Paper Engineering Senior Theses

Since so many of today's papers are used for applications which require a low hygroexpansivity this property of paper is becoming increasingly important. There are many different types of paper which must be stable against changes in dimensions. Papers used in such diverse applications as recording charts, punch cards, paper recording tapes, and packaging boxes all must be stable against dimensional changes in order to function properly in their usage. In the area of printing papers there is a big demand for dimensionally stable paper. Because offset paper is repeatedly exposed to a wet blanket during the color printing process …

The Effects Of Acid Pretreatment On Hydrogen Peroxide And Zinc Hydrosulphite Bleached Deinked Magazine Stock, Philip C. Sturman

Paper Engineering Senior Theses

Magazine papers which have a high groundwood content are deinked in large quantities by the deinking mills. For many uses deinked pulp produced from these papers must be bleached. The commonly practice industrial methods are not wholly satisfactory due to the high shrinkage and lack of brightness stability of the pulp they produce.

In this research project a high groundwood content magazine paper is deinked, washed and bleached. The following bleaching sequences are applied to the portions of the pulp: a single stage hydrogen peroxide treatment, a single stage zinc hydrosulphite treatment and a two-stage hydrogen peroxide-zinc hydrosulphite treatment. In …

The Utilization Of Hydrogenated Tall Oil In Paper Furnishes, Thomas W. Asmus

Paper Engineering Senior Theses

A literature survey is presented concerning the properties of tall oil, the theory of catalysis, and catalytic hydrogenation applied to tall oil. It is the purpose of the experimental work to prepare a material from tall oil by hydrogenation which will lend itself more useful as a sizing agent for certain low grades of paper.

The experimental results indicated that by hydrogenating tall oil soap, a whiter, less oily material is obtainable. Handsheets were prepared using this hydrogenated material, the starting material, and rosin size as sizing agents. It was found that the handsheets sized with the hydrogenated material had …

Historical And Theoretical Survey Of The Effect Of A Cationic Starch On The Hygroexpansivity Of Paper, Anthony Richard Wagner

Paper Engineering Senior Theses

The effect of a cationic starch as an additive on the hygroexpansivity of paper was made. It was found that the hygroexpansivity of the paper increases as the freeness of the stock is lowered. Small additions of cationic starch gave a substantial strength increase with approximately the same expansivity as the lower strength paper made with pulp alone.

The Effect Of Wet Strength Resins On The Dimensional Stability Of Paper, Robert Carey Jr.

Paper Engineering Senior Theses

Introduction

For many grades of paper, dimensional stability is very important in order for the paper to serve its specific purpose. Included in this category are such papers as map paper, template paper, printing papers, and chart paper. Dimensional stability may be improved by subjecting the fibers to less refining, but strength and other properties suffer as a result. Thus, any material which could be added to the fibers to increase dimensional stability would be welcomed by the paper industry.

The purpose of this thesis is to establish whether a particular type of material, wet strength resins, will improve dimensional …

The Influence Of Stock Surface Properties On Grease Resistant Films, John H. Deryke

Paper Engineering Senior Theses

Introduction

One of the main problems in applying a continuous film to a fibrous surface such as paper is that coating must cover fibers that lie in every direction. This produces a relatively rough mat, with some fibers protruding. The surface of paper varies, but all papers and board have a surface configuration resembling a range of mountains. In paper, the interstices can be loaded with fillers, but with boards, fillers are not practical due to the amount necessary. Thus, in coating board with a continuous film, the surface configuration of the board is this main determining factor of the …

Differences In Picking Properties Between Casein And Soya Proteins, Shinya Takekawa

Paper Engineering Senior Theses

In this paper, the various picking properties are discussed at first, then in the experiment the fundamental differences between soya protein and casein in picking strength were studied.

Since it is considered that the penetration of the adhesives in a coating mixture into the base paper is important in picking, the picking strength of casein and soya protein were evaluated in functions of the beating level, sizing level and the amount of the adhesives. Whole experimental data were treated with the statistical method.

The results indicate that with the Wax test, the soya protein and casein have almost equal picking …

Cold Caustic Soda Pulping Of Eucalyptus Saligna, Tachipully A. Bhaskaran

Paper Engineering Senior Theses

A survey has been prepared covering the literature on the cold caustic soda pulping of Eucalyptus saligna. The survey was broadened to include pulping of all species of Eucalyptus by this particular process.

Experimental pulping of Eucalyptus saligna by the cold caustic soda process under a variety of conditions as well as pulping of aspen wood under one condition led to the following conclusions:

(a) Eucalyptus saligna is suitable for the manufacture of cold caustic soda pulp.

(b) alkali concentration of 30 grams per liter on full size chips of Eucalyptus saligna produces the best strength properties and fairly good …

A Quantitative Study Of The Effect Of Cutting & Fibrillation On Certain Paper Properties, Edwin C. Abbott

Paper Engineering Senior Theses

Introduction

From the time of the invention of paper about the year 105 by Ts'ai Lun, the process of beating the pulp as a preliminary to forming a sheet of paper has been recognized as of prime importance.

Early papermakers did not concern themselves greatly with theories; it was enough to know the process necessary to produce the various combinations of long and short, slow and free stocks according to the paper being made. When chemists began to enter the mills, however, their attention was naturally drawn to this important aspect of beating, and to the relationship between cellulose and …

Cold Caustic Soda Pulp From Aspen Wood Some Facts On The Material Dissolved By The Process, Ralph D. Herrick

Paper Engineering Senior Theses

The available literature on the cold caustic soda pulping process, the composition of aspen wood, the composition of spent liquor from other pulping processes, paper chromatographic methods suitable for the analysis of wood and pulp hydrolyzates, and the material removed from aspen wood by the cold caustic soda pulping process have been surveyed.

Aspen wood hydrolyzates were analyzed using n-butanol: pyridine: water solvent system by paper chromatographic methods. Cold caustic soda pulp was prepared using a two hour soaking period at 25°^c temperature, and a 24 gram per liter caustic soda solution with a wood to liquor ratio …

Use Of Dialdehyde Starch In Coating Color Formulation, Craig F. Panse

Paper Engineering Senior Theses

A literature survey was conducted to determine what work, if any, had been done on dialdehyde starch as a coating adhesive. As a result of the survey, it was decided that experimental work would be started with the hope of overcoming some of the difficulties which confronted previous investigators and investigating further the use of dialdehyde starch as an adhesive.

After experimental preparation and evaluation of the coated and aftertreated sheets, the following conclusions were formed:

1. The addition of ten percent borax buffered or bisulphite buffered dialdehyde starch to conventional oxidized starch increases the surface strength of the coating …

A Study Of The Relationship Between Compressibility And Printing Smoothness, Richard R. Teugh

Paper Engineering Senior Theses

This investigation seems to indicate that printing smoothness, although dependent upon both smoothness of the sheet and compressibility, is much more dependent upon the smoothness of the paper being printed. For the samples tested printing pressure required seems to be a function of the smoothness and the deformation pressure with the smoothness apparently most important.

The Potential Production Of Furfural From Sulfite Spent Liquors, Dale Keiser

Paper Engineering Senior Theses

Summary

Furfural was obtained in significant amounts by the action of mineral acid on pentose sugars. Pentose sugars are present in Sulfite Spent Liquors because of the hydrolysis which takes place during the pulping. The dehydrating action of the acid on the pentoses takes place during the pulping. The dehydrating action of the acid on the pentoses takes place at about 100 degrees Centrigrade. The furfural was distilled from the raw acidified spent liquor and can be purified further by fractional distillation. Hardwood Sulfite Spent Liquors gave the highest yields. This is because hardwoods contain more five carbon sugars. A …

The Bleaching Of Groundwood, Dale C. Hedquist

Paper Engineering Senior Theses

Present industrial methods for the bleaching of groundwood are discussed. The conditions and chemicals used for hypochlorite, sodium and zinc hydrosulphite, bisulphite and sodium and hydrogen peroxide bleaching are reviewed. Consistencies, retention time, pH and temperature for maximum brightness are discussed for each process. Chemical reactions for the removal of color are given for several of the processes.

The Effect Of Starch On Clay Dispersions, John L. Moore

Paper Engineering Senior Theses

Cationic starches and anionic (oxidized) starches are compared in this thesis with respect to their effect upon dispersion. The methods used for determining dispersion quality were relative sediment volume (RSV) and the Hercules Hi-Shear Viscometer. These methods are compared as to-their applicability for use as practical. tools in determining color dispersion quality. Limitations of RSV are discussed with regard to clay-starch mixtures. Comparisons are made using both types of starch on predispersed and undispersed clays. Hercules rheograms are compared for samples using both starches and clays at 40 percent solids. The rheograms indicate no difference between the cationic and anionic …

A Study Of The Character Of Spent Liquor From The Neutral [Sic] Sulfite Semichemical Process Of Pulping, Bob Legault

Paper Engineering Senior Theses

Introduction

The utilization of spent liquors has been a major item in the research and development field of the pulp an paper industry. In recent years, this problem is being given more serious emphasis due to the tightening of antipollution laws by government agencies. This situation, together with the individual mill's desire to find programs for sound and effective recovery of values are major recipients of engineering and research man hours and dollars. This all points towards a better future for the industry and the community. A closer study than just analysis and physical constants determination is undoubtedly needed in …

Distribution Of Latex In Impregnated Paper, Donald Ward Nay

Paper Engineering Senior Theses

Introduction

Impregnation of paper products first began in the early 1920's. It became an important aspect of the industry during World War II when several factors came together to provide the basis for its growth. First of all, the development of synthetic materials provided many new agents with new properties in which to impregnate with. New equipment available at this same time made application and control of the process much easier. To put the drive in the new area, there simultaneously occurred a realization of many new products that impregnated papers could provide. The most important of those during World …

The Effect Of Ultraviolet Light On The Color Of Unbleached Pulps: Literature Survey, David L. Brew

Paper Engineering Senior Theses

A literature survey was prepared which covered the published information on the effects of ultraviolet light on the color of unbleached pulps.

Experiments were conducted with eight types of unbleached pulp which were converted into optical test pads under varying pH conditions, using sulphuric acid and caustic soda as well as alum and sodium aluminate for adjustment of the hydrogen ion concentration. The optical test pads were exposed to ultraviolet irradiation. Thereafter, reflectance measurements were taken, covering the range of visible light.

From the limited number of experiments which were conducted we can conclude that:

1. Unbleached coniferous kraft, unbleached …