Disclosed herein is a mixed phosphate catalyst for converting lactic acid to acrylic acid, which is characterized by a high conversion of lactic acid, a high selectivity for acrylic acid, a high yield of acrylic acid, and correspondingly low selectivity and molar yields for undesired by-products. This is achieved with a particular class of catalysts defined by a mixture of metal-containing phosphate salts. Further, the catalyst is believed to be stable and active for lengthy periods heretofore unseen in the art for such dehydration processes.

A method for making a disposable absorbent core comprises depositing absorbent particulate polymer material from a plurality of reservoirs in a printing roll onto a substrate disposed on a grid of a support which includes a plurality of cross bars extending substantially parallel to and spaced from one another so as to form channels extending between the plurality of cross bars. The plurality of reservoirs in the first peripheral surface are arranged in an array comprising rows extending substantially parallel to and spaced from one another. A disposable absorbent article and apparatus for making an absorbent article are also disclosed.

Processes for the purification of bio-based acrylic acid to crude and glacial acrylic acid are provided. The bio-based acrylic acid is produced from hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof. The purification includes some or all of the following processes: extraction, drying, distillation, and melt crystallization. The produced glacial or crude acrylic acid contains hydroxypropionic, hydroxypropionic acid derivatives, or mixtures thereof as an impurity.

Processes for the catalytic dehydration of hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof to acrylic acid, acrylic acid derivatives, or mixtures thereof with high yield and selectivity and without significant conversion to undesired side products, such as, acetaldehyde, propanoic acid, and acetic acid, are provided.

Methods for catalytically dehydrating hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof to acrylic acid, acrylic acid derivatives, or mixtures thereof with high yield and selectivity and without significant conversion to undesired side products, such as, acetaldehyde, propionic acid, and acetic acid, are provided. The catalysts are mixed condensed phosphates.

An absorbent pad includes a batt of cellulose fibers, superabsorbent particles intermixed within the batt of cellulose fibers, and an odor control material intermixed within the batt of cellulose fibers, wherein the odor control material is a particulate material including one or more fatty acid. The odor control material preferably further includes selected inorganic compounds, such as sources of nitrogen, phosphorus and iron. Various embodiments incorporate the absorbent pad in a diaper or other disposable hygiene product.

The present invention addresses the problem of providing an absorbent article in which a bonding part for bonding a liquid-permeable layer to an absorbent core has been formed in a low-basis-weight region of the absorbent core and which has all of sufficient flexural rigidity of the bonding part, sufficient bonding strength of the bonding part, and sufficient liquid-absorbing properties. This problem is solved with an absorbent core which comprises a first region that has a given absorbent-material basis weight and second regions (regions 411a, 411b) that have a lower absorbent-material basis weight than the first region, wherein the ratio of the basis weight of a highly absorbing polymer to the basis weight of the absorbent material in the second regions is regulated to 10/100 to 47/100, and compressed parts are formed inside the second regions.

The present disclosure generally relates to disposable diapers having absorbent cores comprising superabsorbent polymer particles which are immobilized by adhesive. The absorbent cores are attached to the backsheets of the disposable diapers in certain attachment zones to reduce see-through and the formation of tension lines on the backsheets.

Bio-based glacial acrylic acid, produced from hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof and having impurities of hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof, is polymerized to poly(acrylic acid) or superabsorbent polymer using the same processes as petroleum-derived glacial acrylic acid.

An absorbent body in absorbent articles that causes exudates to disperse in a planar direction and a method of producing the same. The absorbent body has an absorbent core material covered with a cover sheet. The core material has a mass per unit area of 650 g/m.sup.2 or less and includes a first liquid absorbent layer containing hydrophilic fibers and superabsorbent polymer particles in a mixed state and a second liquid absorbent layer containing the hydrophilic fibers but none of the superabsorbent polymer particles, wherein the first liquid absorbent layer and the second liquid absorbent layer are overlap with each other and the hydrophilic fibers are in contact with each other between the first liquid absorbent layer and the second liquid absorbent layer.